Directory UMM :Data Elmu:jurnal:E:Environmental Management and Health:Vol11.Issue5.2000:
The research register for this journal is available at
http://www.mcbup.com/research_registers/emh.asp
The current issue and full text archive of this journal is available at
http://www.emerald-library.com
Risk assessment of
radiation-induced thyroid
cancers in Belarus
Mikhail V. Malko
Radiationinduced thyroid
cancers
455
Institute of Radiation Physical and Chemical Problems,
National Academy of Sciences of Belarus, Minsk,
Republic of Belarus
Keywords Risk, Radiation, Belarus
Abstract The paper presents results of a qualitative assessment of the morbidity and mortality
in thyroid cancers by the Belarusian population caused by the Chernobyl accident. In the period of
1986-1998 about 3,851 radiation-induced thyroid cancers appeared in Belarus: about 615
cancers by children and about 3,236 cancers by adolescents and adults. The number of lethal
thyroid cancers in this period of time in Belarus is assessed as about 167 cases. The excessive
absolute risk (EAR) of the morbidity in the thyroid cancer assessed for the period of 1986-1998
on the basis of given data on the morbidity is about 1.7 per 104 PYGy. The excessive absolute risk
of mortality is assessed as about 0.075 per 104 PYGy. These values agree quite well with
analogous risk coefficients established for other groups of people in other epidemiological studies.
Introduction
As a result of the Chernobyl accident a large amount of radioactive substances
escaped from the destroyed reactor. Especially high release was in the case of
volatile radionuclides. So according to the existing assessments about 50-60 per
cent of the 131I isotope inventory came into the environment (GuÈntay et al., 1997).
This caused the radioactive contamination of many countries of the Northern
Hemisphere. However, Belarus was affected by the accident most of all.
Practically the whole territory of Belarus was contaminated with different
radionuclides (Matveenko et al., 1997). This resulted in irradiation of the whole
Belarusian population. In the early stage of the accident the radiation situation
was determined mostly by short-lived radionuclides. A very important role at
this time was played by iodine isotopes. They caused irradiation of thyroid
glands of children, adolescents and adults of the whole Belarus. However, the
highest doses to the thyroid glands were delivered to inhabitants of Gomel and
Brest oblasts (regions). For example, the arithmetic mean thyroid dose in the age
group 0-6 years by children living in settlements settled in the 30km zone was
about 4.7 Gy and maximal doses were about 50Gy (Gavrilin et al., 1999). For
inhabitants of this settlement aged 7-17 years at the moment of the accident the
thyroid dose was about 2.1Gy and for adults about 1.6Gy. The extensive
irradiation of the thyroid gland by the Belarusian population caused very soon
after the accident a significant increase in the incidence in thyroid cancers. This
effect was especially very pronounced for children, who are more sensitive to
irradiation and that received much higher doses than adolescents and adults.
Environmental Management and
Health, Vol. 11 No. 5, 2000,
pp. 455-467. # MCB University
Press, 0956-6163
EMH
11,5
456
The first reliable data on a sharp increase in the thyroid cancer morbidity by
children of Belarus after the Chernobyl accident were published in 1992
(Kazakov et al., 1992). However, specialists met these data with great
scepticism (Ron et al., 1992). There were serious reasons for this scepticism.
First, the published data on the incidence of thyroid cancers have shown an
unusual short latent period of about two to three years. Second, no similar data
about the increase in the incidence of thyroid cancer by children of the affected
areas of the Ukraine and Russia were known at that time. And this was very
strange because all specialists believed that the Ukraine was affected by the
Chernobyl accident much more than Belarus. It is now clear that such
assumption was totally incorrect.
In order to explain an unusually high incidence of thyroid cancer in the
children of Belarus some specialists proposed the idea that this increase was
caused by the improved screening in Belarus (Ron et al., 1992).
This situation changed only after the first international conference on the
radiological consequences of the Chernobyl accident held in Minsk in 1996 from
18-22 March. At the conference new data on the thyroid cancer incidence in
Belarus (Demidchik et al., 1996a) as well as similar data on the increase in the
thyroid cancer incidence by children of the Ukraine (Tronko et al., 1996) and
Russia (Tsyb et al., 1996) were presented. Data on the thyroid cancer morbidity
by children of these two countries differed only quantitatively from the
Belarusian data.
At the Minske conference an amount of evidence was given which shows
that the increase in the incidence of thyroid cancer in the children and
adolescents of Belarus, the Ukraine and Russia had its origins in radiation.
So it was shown that, in Belarus, thyroid cancer has mainly appeared in
children irradiated as a result of the Chernobyl accident. Out of the total
number of 390 thyroid cancers registered by children of Belarus in 1986-1994
and first seven months of 1995, 380 cases were diagnosed by children born
before the Chernobyl accident, six cases by children born at the time of the
accident and only four cases by children born after full disintegration of
radioiodine (Demidchik et al., 1996a). Another very important finding relates to
the histological types of thyroid cancers in countries affected by the Chernobyl
accident. For instance, more than 90 per cent of thyroid cancers in Belarus and
the Ukraine were papillary carcinoma as compared with 68 per cent in England
and Wales (Williams et al., 1996). Within the papillary carcinoma, over 70 per
cent of thyroid cancers in the countries affected by the Chernobyl accident were
of the solid follicular type, compared to only 40 per cent in England and Wales.
At present practically all specialists are sure that the sharp increase in the
incidence in thyroid cancer established by the children of Belarus, the Ukraine
and Russia after the Chernobyl accident has its origins in the radiation.
It is noticeable here that many specialists, especially in Western countries
believe that besides radiation-induced thyroid cancers in the children of Belarus,
the Ukraine and Russia no other medical effect was caused by the Chernobyl
accident in these countries. Such an assumption is incorrect, at least for Belarus
where an increase in the incidence of thyroid cancer in adolescents and adults
was also registered after the accident. Existing assessment (Malko, 1998a) shows
that in the period 1986-1997 about 2,708 additional thyroid cancers were manifest
in adolescents and adults of Belarus in comparison with 562 cases of children. As
can be seen from these data the number of additional thyroid cancers manifest in
adolescents and adults of Belarus in the period 1986-1997 is five times higher
than that for children. This fact indicates that assessment of the real harm of a
radiological accident of the scale of the Chernobyl accident requires consideration
of all irradiated groups of the affected population.
One of the tasks of this report is the assessment of the total number of
additional thyroid cancers manifest in Belarus in the period 1986-1998, as well
as finding arguments that show a positive association between these additional
thyroid cancers and irradiation of people as a result of the Chernobyl accident.
It seems that assessment of the excessive absolute risk (EAR) of the
radiation-induced thyroid cancer can provide such arguments. This task is
solved on the basis of data established in Belarus because the population of this
country received the highest thyroid doses (Malko, 1998b). Due to this fact a
clearer manifestation of the irradiation effects may be expected in Belarus. It is
also important that the epidemiological data established in Belarus are more
comprehensive and accurate than in Russia and the Ukraine.
Materials and method
Assessment of the morbidity in thyroid cancers by children, adolescents and
adults of Belarus after the Chernobyl accident was carried out on the basis of
published data of the Scientific Center for Thyroid Cancer of Belarus
(Demidchik et al., 1996a; 1996b; Demidchik, 1998; Demidchik, 2000) as well as
published data of the Belarusian Cancer Registry (1999).
These centers collect all information about thyroid cancers in children,
adolescents and adults registered in all regions of Belarus. This monitoring of
the manifestation of thyroid cancers was carried out from the 1960s.
Analysis of publications of the Scientific Center for Thyroid Cancer of
Belarus and of the Belarusian Cancer Registry shows that they give practically
the same data on the incidence of thyroid cancers in children, adolescents and
adults of Belarus. The only one difference is that the Center publishes the
absolute numbers of thyroid cancers and the Registry gives the crude incidence
rates as well as age standardized morbidity rates. The Registry gives also
information about mortality from thyroid and other cancers.
The excessive absolute risk was assessed in the paper on the basis of the
following expression:
EAR O ÿ E c= Hcoll n;
where:
O = observed number of cases;
E = expected or spontaneous number of cases;
1
Radiationinduced thyroid
cancers
457
EMH
11,5
458
c
= coefficient allowing for the screening effect;
coll
H = collective dose of the thyroid gland irradiation;
n = number of years under observation.
The value of the coefficient c in the present work was taken equal to 1 because
no correct information about a contribution of the screening effect to the
incidence in thyroid cancers by children, adolescents and adults of Belarus
before and after the Chernobyl accident is known.
In the case of children, as an expected number of thyroid cancers, 1 case per
year was taken as follows from data of the Belarusian Thyroid Cancer Center
(Demidchik et al., 1996b). So according to these data in 1966-1985 (or during 20
years before the Chernobyl accident) only 21 cases of thyroid cancer were
registered by children of Belarus. This gives one case of thyroid cancer per year
as a spontaneous morbidity in the thyroid cancer for the Belarusian children.
The average number of children (less than 15 years old) in Belarus in the preaccidental period was about 2.5 million (Public Health, 1997). As can be
calculated from this figure the spontaneous morbidity in thyroid cancer by
children of Belarus before the Chernobyl accident was approximately 0.4 cases
per million. This value is very close to the spontaneous morbidity in thyroid
cancer in children of England and Wales (Williams et al., 1966), that is
approximately 0.5 cases per million.
The expected numbers of thyroid cancers in adolescents and adults of
Belarus were assessed on the basis of the formula (Malko, 1998a):
Ej E0 : 1 aj ;
2
Here:
E0 = spontaneous morbidity of adolescents and adults in 1977 (121
cases);
a = is a constant showing the annual increase in the incidence of the
thyroid cancer, it is about 0.2 (2 per cent increase annually);
j = is a number of the consequent year beginning with j = 0 for 1977
(j = 1 for 1978 and so on);
Ej = spontaneous morbidity of adolescents and adults in the jth year.
The last expression was established by using observed incidence in thyroid
cancers by adolescents and adults of Belarus before the Chernobyl accident
(Demidchik et al., 1996a). In the present paper it was used for calculation of
expected thyroid cancers in this group of population after the Chernobyl
accident. Results of calculation together with observed data (Demidchik et al.,
1996a) are presented in Table I. Here are also given observed and expected
numbers of thyroid cancers by children of Belarus in 1977-1985.
As can be seen from Table I, observed (Demidchik et al., 1996a) and expected
numbers of thyroid cancers in children, adolescents and adults of Belarus in
Children
Observed
Expected
Year
1977
1978
1979
1980
1981
1982
1983
1984
1985
Total
2
2
0
0
1
1
0
0
1
7
Adolescents and adults
Observed
Expected
Corrected
1
1
1
1
1
1
1
1
1
9
121
97
101
127
132
131
136
139
148
1,131
121
123
126
128
131
134
136
139
142
1,180
121
123
126
127
132
131
136
139
148
1,182
Radiationinduced thyroid
cancers
459
Table I.
Thyroid cancer in
Belarus before the
Chernobyl accident
1977-1985 tally quite well. For example, the difference between numbers of
observed (1,131 cases) and expected (1,180) thyroid cancers in adolescents and
adults of Belarus in this period of time is only 49 cases or about 4.3 per cent.
This means that our assumption about the spontaneous morbidity of thyroid
cancer in Belarus before the Chernobyl accident is quite correct. Data in this
table show that the largest difference in observed and expected numbers of the
thyroid cancer in the case of adolescents and adults took place in 1978 and
1979. It is about 25 per cent. It resulted possibly from underestimation of
observed thyroid cancers in 1978 and 1979. By using for these years data
calculated with the expression (2) as observed data, the difference in total
amounts of observed and expected numbers of thyroid cancers manifest in
adolescents and adults in the period 1977-1985 decreased by up to 0.16 per cent.
Observed numbers of thyroid cancers in adolescents and adults of Belarus
corrected in this way are given in the sixth column of Table I.
Results and discussion
Table II and Figure 1 show observed data (Demidchik, 1998) on the thyroid
cancer morbidity of children of Belarus after the Chernobyl accident. Data in
Table II demonstrates an increase in the incidence of the thyroid cancer
manifest in children of all regions of Belarus. However, the largest increase
Region
Brest
Vitebsk
Gomel
Grodno
Minsk
Mogilev
Minsk-city
Belarus total
Year
1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 Cases
0
0
1
1
0
0
0
2
0
0
2
1
1
0
0
4
1
0
1
1
1
0
1
5
1
0
3
2
1
0
0
7
7
1
14
0
1
2
4
29
5
3
43
2
1
3
2
59
17
2
34
4
4
1
4
66
24
0
36
3
4
7
5
79
21
1
44
5
6
4
1
82
21
0
48
5
1
6
10
91
25
0
42
5
5
3
4
84
13
0
37
3
6
4
3
66
135
7
305
32
31
30
34
574
Table II.
Thyroid cancer in
children of Belarus
after the Chernobyl
accident
EMH
11,5
460
Figure 1.
Dynamics in the thyroid
cancer incidence in
children of Belarus after
the Chernobyl accident
appeared in the Gomel and Brest regions. The geographical distribution of
thyroid cancers by Belarusian children correlates with levels of contamination
by 131I isotope in Belarus (Matveenko et al., 1997).
The summary data from Table II were also used to construct Figure 1, which
shows the temporary trend in the thyroid cancer incidence in children of
Belarus in the time from 1986 up to 2004. Here numbers of thyroid cancers
registered by children in 1986-1999 (Demidchik et al., 1996a; Demidchik, 1998;
2000) and data forecast for 2000-2004 are presented.
As can be seen from Table II and Figure 1, the incidence of thyroid cancer in
children of Belarus reached the maximum in 1995 and then began to decrease.
The reason for this decline is very easily explained. It was explained on the
basis of a transition model (Malko, 1998a). All official data on the cancer
morbidity in Belarus are given for two groups. The first group includes data for
those people for which any cancer, as well as the thyroid cancer, was diagnosed
when they were less than 15 years old. The second group includes all people
who are older than 15 years. Thus, when a person reaches 15 years at the time
of the thyroid cancer diagnosis this person will be considered as a person
belonging to the group of adolescents and adults. This means that the observed
decline in the morbidity in thyroid cancer in children of Belarus originates from
the method of medical registration used in Belarus.
The last children with thyroid glands irradiated as a result of the Chernobyl
accident will pass into the category of adolescents and adults in 2001. To this
group belong children irradiated in-utero and born some months after the
explosion of the Chernobyl reactor. Thus the incidence of thyroid cancer in
children of Belarus in 2002 has to change to the spontaneous rate that was
assessed in this paper as one case per year for the whole of Belarus.
By forecasting of numbers of thyroid cancers for 2000-2004 the following
simplified procedure was used. A total 54 cases of thyroid cancers in 1998 and
49 in 1999 by children of Belarus were registered (Demidchik, 2000). Linear
extrapolation between 49 cases in 1999 and one case in 2002 gives for the years
2000 and 2001, 32 and 16 thyroid cancers respectively. The total number of
thyroid cancers in the Belarusian children that can manifest in the period from
1986 up to 2002 will be then equal to 725 cases. Subtracting from this number
the number of spontaneous thyroid cancers that have to appear in 1986-2001
(15 cases) will give the total number of thyroid cancers in children of Belarus
that will be caused as a result of the Chernobyl accident, equal to
approximately 710 cases.
Data on the number of thyroid cancers registered by adolescents and
adults of Belarus in 1986-1997 given in the second column of Table III were
taken from the report (Demidchik, 1998). The number of thyroid cancers in
this column for 1998 were calculated on the basis of the morbidity rate
(Belarusian Cancer Registry, 1999) of thyroid cancer of the whole Belarusian
population.
According to report of the Belarusian Cancer Registry (1999) this rate was 7.5
cases per 100,000 people in 1998 and the total number of people in Belarus was
10.2 million. By using these data one can calculate the total number of thyroid
cancers registered in Belarus in 1998 as being equal to 765 cases. This number
is a sum of thyroid cancers established by children and adolescents and adults.
Subtraction of the number of children's cancers (54 cases in 1998) from this
value gives 711 cases as a number of thyroid cancers registered in 1998 by
adolescents and adults. This number is shown in Table III.
The third column of Table III gives numbers of spontaneous thyroid cancers in
1986-1998 calculated by using the expression (2). The fourth column of this
table presents the numbers of additional thyroid cancers manifest in
Year
Observed
Expected
Observedexpected
Sir
95 per cent CI
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
Total
162
202
207
226
289
340
416
512
553
531
568
641
711
5,358
145
147
150
153
157
160
163
166
169
173
176
180
183
2,122
17
55
57
73
132
180
253
346
384
358
392
461
528
3,236
1.12
1.37
1.38
1.48
1.84
2.13
2.55
3.08
3.27
3.07
3.23
3.56
3.89
2.52
0.95-1.30
1.19-1.57
1.20-1.58
1.29-1.68
1.64-2.06
1.91-2.36
2.31-2.81
2.83-3.36
3.01-3.56
2.82-3.34
2.97-3.51
3.29-3.85
3.61-4.18
2.46-2.59
Radiationinduced thyroid
cancers
461
Table III.
Thyroid cancer in
adolescents and adults
of Belarus after the
Chernobyl accident
EMH
11,5
462
adolescents and adults of Belarus in this period. The fifth column shows the
standardized incidence ratio and the sixth column gives the confidence
intervals estimated for SIR on the basis of the Poisson distribution.
The data of Table III show that the incidence of thyroid cancer in
adolescents and adults of Belarus increased after the Chernobyl accident at
least by a factor of two to three in comparison with the incidence before the
accident. This increase resulted in the number of additional thyroid cancers
equal to 3,236 cases. It is clear that the accuracy in the assessment of additional
thyroid cancers depends very strongly on the accuracy in determination of the
background morbidity before the Chernobyl accident, because the background
morbidity in this period of time is used in the present paper for assessment of
expected thyroid cancers after the accident. It is also evident that
underestimation of the morbidity in thyroid cancers will be important only
when after the accident a significant improvement in screening has taken place.
This effect or the effect of improved screening is especially important in case of
adolescents and adults because of a rather elevated increase in the incidence of
thyroid cancers in this group of population after the Chernobyl accident. The
effect of improved screening is not so important in the case of children because
of a very large increase in the incidence in thyroid cancers by them.
Unfortunately, at the present time there is no such information for Belarus
that could be helpful by answering the question what contribution to the
assessed numbers of additional thyroid cancers by adolescents and adults gave
the effect of improving in screening after the Chernobyl accident. However, it
seems unreasonable to explain the evident increase in the incidence of thyroid
cancers in adolescents and adults of Belarus after the accident exceptionally on
the basis of the idea of improved screening. At least partly this increase has to
be a real effect because of the transition from the group of children into the
group of adolescents and adults. It should also be noticed here that a marked
increase in the incidence of thyroid cancers in adolescents and adults was
registered in 1987-1989, when there was no necessity for radical improvement
of medical screening in Belarus. It is well known that in the former USSR only
some areas in the northern Ukraine were considered as affected by the accident
during the first three years after the accident. The first official and realistic
information about radiological problems of Belarus caused by the Chernobyl
accident appeared only three years after the accident. This was the time of
aggravation of the economic situation in Belarus as well as in the whole USSR.
So there was also no economic base for a significant improvement in screening
of thyroid cancer in Belarus at all. Relating this problem, one needs also to
notice that the incidence of the thyroid cancer in Belarus before the Chernobyl
accident was practically the same as in some counties of the UK and in some
other European countries. Calculation on the basis of corrected observed
numbers of thyroid cancers (see the sixth column of Table I) gives, for the
period 1978-1982, the mean age standardized (world standard) value of the
morbidity rate of thyroid cancer for Belarusian population equal to 1.1 per
100,000 people. Practically the same standardized values were determined in
1978-1982 in different counties of the UK, as well as in different areas of Poland,
Romania and other European countries. This agreement shows that the level of
medical screening in Belarus before the Chernobyl accident was the same as in
other European countries. Thus it is unreasonable to believe that the increase in
the incidence of thyroid cancers in Belarus in the period 1986-1998 results from
the improvement in the screening.
The total number of additional thyroid cancers in children, adolescents and
adults of Belarus in 1986-1998 calculated on the basis of the data discussed
above is equal to 3,851 cases. The collective thyroid dose of the Belarusian
population according to the assessment (Malko, 1998b) is about 12.7105
manSv. By this assessment a conversion coefficient 0.72Sv/Gy was used.
Considering this fact one can calculate the collective thyroid dose of the
Belarusian population also as 17.6105 man.Gy. Inserting this value and the
number of additional thyroid cancers that was assessed in this work (3,851
cases) into the expression (1) one can estimate the EAR of the radiation-induced
thyroid cancers caused in Belarus by the Chernobyl accident as being equal to
1.7 per 104 PYGy.
This value tallies completely with the excessive absolute risk of radiationinduced thyroid cancer that was established for the period 1990-1997 for those
inhabitants of the city Kiev and Ukrainian regions closest to the Chernobyl
NPP (Chernigov, Kiev and Zhytomir regions) that were 0-18 years old at the
time of the Chernobyl accident (Likhtarev et al., 1999). In 1997 they were 11-31
years old. For this fraction of the affected Ukrainian population the value of the
EAR equal to 1.7 per 104PYGy was established.
The EAR value that was assessed in the present work agrees also very well
with EARs established in other studies. For example, the value of EAR that
was established for the period 1958-1987 by atomic bomb survivors is 1.6 per
104 PYSv with 95 per cent CI 0.78-2.5 per 104 PYSv. By transforming to other
units these values gives the EAR equal to 1.1 per 104 PYGy ( 95 per cent CI =
0.55 ± 1.75). In the study of inhabitants of the Marshall Islands that had a
strong internal irradiation of the thyroid gland with 131I the EAR was
estimated as 1.1 per 104 PYGy (Robbins and Adams, 1989). Study of
consequences of the Utah 131I fallout (Kerber et al., 1993) gave the value of EAR
equal to 3.3 per 104PYGy. According to the pooled analysis of Ron et al. (1995),
the excessive absolute risk of the acute external irradiation of thyroid glands
by people aged less than 20 is 4.4 per 104 PYGy (95 per cent CI = 1.9 ± 10).
Agreement between the values of EAR established in this and other works
permits a number of conclusions, which are the following. First, one can believe
that the number of additional thyroid cancers that was assessed in this work is
quite reasonable. It means that, in the period of time 1986-1998, in Belarus
about 615 radiation-induced thyroid cancers appeared in children and about
3,236 thyroid cancers in adolescents and adults. Second, this agreement reveals
the correctness of the assessed collective thyroid dose of the Belarusian
population (Malko, 1998b) used in the present paper by estimation of the
excessive absolute risk. It is clear that a reasonable value of the excessive
Radiationinduced thyroid
cancers
463
EMH
11,5
464
Figure 2.
Mortality rate in Belarus
from the thyroid cancer
after the Chernobyl
accident
absolute risk can be achieved only in case of having quite accurate data on the
numbers of radiation-induced cancers and on the collective thyroid dose of the
irradiated group of people. Third, the early manifestation of radiation-induced
thyroid cancers in Belarus shows clearly that the latent period of the thyroid
cancer, at least in Belarus, is less than five years. This is not surprising. Such a
possibility was forecast a long time ago (Gofman, 1981). It was proposed that
the latent period of any cancer had to depend on the number of people in the
group under study. In the case of a small group a very long time can be needed
in order to get a provable difference within a control group. By contrast, in the
case of a very large group of irradiated people, the provable difference can be
reached in a very short time. Such a situation is realized in Belarus where
thyroid glands of approximately 10,000,000 people were irradiated.
The similar procedure as in the case of the thyroid cancer incidence can be
used for assessment of a number of people in Belarus that died from the thyroid
cancer caused by the Chernobyl accident.
Figure 2 shows the dynamic in the crude mortality rate resulting from the
morbidity in thyroid cancers. These data were taken from reports of the
Belarusian Cancer Registry (Public Health Ministry of the Republic of Belarus,
1997; Tsyb et al., 1996; Williams et al., 1996). They give the mortality in thyroid
cancers of the whole Belarusian population (children, adolescents and adults).
The upper (solid) line gives the observed mortality rates. The lower (dotted)
line shows the ``spontaneous'' mortality rates as determined by us. Using these
data as well as data on a number of people in Belarus in 1986-1998 (it is about
10 million people) gave approximately 167 fatal cases resulting from the
radiation-induced thyroid cancers for this period of time.
The excessive absolute risk of mortality resulting from the radiation-induced
thyroid cancers calculated on the basis of this number and the collective
thyroid dose of the Belarusian population is equal to 0.075 per 104 PYGy. This
value is comparable with the excessive absolute risk of mortality from
radiation thyroid cancers by atomic bomb survivors. For this cohort of people
the value of EAR equal to 0.016 per 104 PYSv (95 per cent CI = ±0.04 ± 0.24) was
estimated for the period 1950-1987 (Ron et al., 1994). In other units the excessive
absolute risk of mortality by atomic bomb survivors is 0.011 per 104 PYGy (95
per cent CI= ± 0.028 ± 0.168). As can be seen from these data, there is an
overlapping in values of the excessive absolute risks of mortality from
radiation-induced thyroid cancers estimated in the present paper and by atomic
bomb survivors. This permits the conclusion that the number of people who
have already died in Belarus from radiation-induced thyroid cancers caused by
the Chernobyl accident is assessed in the present paper quite correctly.
Conclusions
.
The morbidity and mortality from radiation-induced cancers in Belarus
as a result of the Chernobyl accident has been assessed for the period of
time 1986-1998. According to this assessment about 615 radiationinduced thyroid cancers in the children of Belarus appeared in 19861998. The total number of children's thyroid cancers that will manifest
in 1986-2001 can be about 710 cases. The number of the radiationinduced thyroid cancers manifested by adolescents and adults of
Belarus in 1986-1998 as a result of the Chernobyl accident was assessed
as approximately 3,236 cases. The total number of radiation-induced
thyroid cancers appearing in this period of time is about 3,851 cases. The
number of people that died in Belarus in 1986-1998 from radiationinduced cancer was assessed as about 167 cases.
.
The excessive absolute risk, EAR, of the radiation-induced thyroid
cancers manifested in Belarus after the Chernobyl accident is assessed
as 1.7 per 104 PYGy. This value agrees with EARs established in other
studies of the morbidity in thyroid cancers as a result of irradiation.
.
The excessive absolute risk of mortality in Belarus in 1986-1998 from
the radiation-induced thyroid cancers was assessed as 0.075 per 104
PYGy in accordance with data established in other studies.
References
Belarusian Cancer Registry (1999), ``Malignant neoplasms in Belarus: 1989-1998''.
Demidchik, E.P. (1998), ``Epidemiology and surgery of thyroid carcinom'', report at the annual
meeting of the German Societies of the Radiation Studies, 16-18 March, FRG, Munich.
Demidchik, E.P. (2000), Private communication.
Demidchik, E.P., Drobyshevskaya, I.M., Cherstvoy, E.D., Astakhova, L.N., Okeanov, A.E.,
Vorontsova, T.V. and Germenchuk, M. (1996a), ``Thyroid cancer in children in Belarus'', in
Karaoglou, A., Desmet, G., Kelly, G.N. and Menzel, H.G. (Eds), Proceedings of the First
Radiationinduced thyroid
cancers
465
EMH
11,5
466
International Conference ``The Radiological Consequences of the Chernobyl Accident'', held
in Minsk, Belarus, 18-22 March, EUR 16544 EN, Brussels-Luxembourg, pp. 677-82.
Demidchik, E.P., Okeanov, A.E., Rebeko, V.Y. and Demidchik, Y.E. (1996b), ``Current trend in
prophylaxies, early diagnosis, and curative treatment of thyroid cancer in Belarus'', in
Takeichi, N., Satow, Y. and Masterson, R.H. (Eds), The Chernobyl Accident. Thyroid
Abnormalities in Children, Congenital Abnormalities and Other Radiation Related
Information. The First Ten Years, 1st ed., Hirosima-Nagasaki Peace Foundation, Japan,
pp. 89-93.
Gavrilin, Y.I., Krouch, V.T., Shinkarev, S.M., Krysenko, N.A., Skryabin, A.M., Bouville, A. and
Anspaugh, L.R. (1999), ``Chernobyl accident: reconstruction of thyroid dose for inhabitants
of the Republic Belarus'', Health Physics, Vol. 76 No. 2, pp. 105-19.
Gofman, J.W. (1981), Radiation and Human Health. A Comprehensive Investigation of the
Evidence Relating Low-level Radiation to Cancer and Other Diseases, Sierra Club Books,
San Francisco, CA, pp. 103-9
GuÈntay, S., Powers, D.A. and Devell, L. (1997), ``The Chernobyl reactor accident source term:
development of a consensus view'', Proceedings of the International Conference ``One
Decade after Chernobyl: Summing up the Consequences of the Accident'', Vol. 2, held in
Vienna, 8-12 April 1996, IAEA, Vienna, Poster presentation, pp. 183-93.
Kazakov, V.S., Demidchik, E.P. and Astakhova, L.N. (1992), ``Thyroid cancer after Chernobyl'',
Nature, Vol. 359, p. 21.
Kerber, R.A., Till, J.E., Simon, S.L., Thomas, D.C., Preston-Martin, S., Rallison, M.L., Lloid, R.D.
and Stevens, W. (1993), ``A cohort study of thyroid disease in relation to fallout from
nuclear weapon testing'', Journal of the American Medical Association, Vol. 270, pp. 207682.
Likhtarev, I.A., Kayro, I.A., Shpak, V.M., Tronko, N.D and Bogdanova, T.I. (1999), ``Radiationinduced and background thyroid cancer of Ukrainian children'', Int. J. Radiat. Med., No. 3-4,
pp. 51-66.
Malko M.V. (1998a), ``Thyroid cancer in Belarus'', in The Radiological Catastrophe in Chernobyl:
Report of the International Study (in Japanese), Tokyo, Japan, pp. 218-22.
Malko, M.V. (1998b), ``Assessment of the Chernobyl radiological consequences'', in Imanaka, T.
(Ed.), Research Activities about Radiological Consequences of the Chernobyl NPS Accident
and Social Activities to Assist the Sufferers by the Accident, Research Reactor Institute,
Kyoto University, Japan, pp. 65-89.
Matveenko, I.I., Germenchuk, M.G., Shagalova, E.D. and Zhukova, O.M. (1997), ``Migration and
forecast of the radioactive contamination of the soil, water and air on the territory of
Belarus after the accident at the Chernobyl NPP'', Proceedings of the International
Conference ``One Decade after Chernobyl: Summing up the Consequences of the Accident'',
Vol. 2, held in Vienna, 8-12 April 1996, IAEA, Vienna, Poster presentation, pp. 64-70.
Public Health Ministry of the Republic Belarus. Medical Statistics Department (1997), Public
Health in the Republic of Belarus. An Official Statistics Collection (in Russian), Public
Health Ministry of the Republic Belarus. Medical Statistics Department, Minsk, p. 30.
Robbins, J. and Adams, W. (1989), ``Radiation effects in the Marshall Islands'', in Nagataki S.
(Ed.), Radiation and the Thyroid, Excerpta Medica, Amsterdam, pp. 11-24.
Ron, E., Lubin, J. and Schneider, A. (1992), ``Thyroid cancer incidence'', Nature, Vol. 360, p. 113.
Ron, E., Lubin, J.H., Shore, R.E., Mabuchi, K., Modan, B., Pottern, L.M., Schneider, A.B., Tucker,
M.A. and Boice, J.D. (1995), ``Thyroid cancer after exposure to external radiation: a pooled
analysis of seven studies'', Radiation Res., Vol. 141, pp. 259-77.
Tronko, N., Bogdanova, T., Komissarenko, I., Bolshova, E., Oleinik, V., Tereshchenko, V.,
Epshtein, Y. and Chebotarev, V. (1996), ``Thyroid cancer in children and adolescents in
Ukraine after the Chernobyl accident (1986-1995)'', in Karaoglou, A., Desmet, G., Kelly,
G.N. and Menzel, H.G. (Eds), Proceedings of the First International Conference ``The
Radiological Consequences of the Chernobyl Accident'', held in Minsk, Belarus, 18-22 March,
EUR 16544 EN, Brussels-Luxembourg, pp. 683-90.
Tsyb, A.F., Parshin, E.M., Shakhtarin, V.V., Stepanenko, V.F., Skvortsov, V.F. and Chebotareva,
I.V. (1996), ``Thyroid cancer in children and adolescents of Bryansk and Kaluga regions'',
in Karaoglou, A., Desmet, G., Kelly, G.N. and Menzel, H.G. (Eds), Proceedings of the First
International Conference ``The Radiological Consequences of the Chernobyl Accident'', held
in Minsk, Belarus, 18-22 March, EUR 16544 EN, Brussels-Luxembourg, pp. 691-7.
Williams, E.D., Cherstvoy, E., Egloff, B., Holer, H., Vecchi, G., Bogdanova, T., Bragarnik, M. and
Tronko, N.D. (1996), ``Interaction of pathalogy and molecular characterization of thyroid
cancers'',in Karaoglou, A., Desmet, G., Kelly, G.N. and Menzel, H.G. (Eds), Proceedings of
the First International Conference ``The Radiological Consequences of the Chernobyl
Accident'', held in Minsk, Belarus, 18-22 March, EUR 16544 EN, Brussels-Luxembourg,
pp. 699-714.
Radiationinduced thyroid
cancers
467
Sponsors
[ S e a rch ] [ Ad va n ce d S e a rch ] [ S u b m it Re s e a rch ] [ Ed it Re s e a rch ] [ He lp ]
We lco m e t o t h e En viro n m e n t a l Ma n a g e m e n t & He a lt h In t e rn e t Re s e a rch Re g is t e r, d e live re d b y
MCB Un ive rs it y Pre s s in a s s o cia t io n wit h t h e I n t e r n a t io n a l Jo u r n a l o f S u s t a in a b ilit y in Hig h e r
Ed u c a t io n a n d t h e fo llo win g in t e rn a t io n a l b o d ie s : THE INTERNATIONAL FEDERATION
OF ENVIRONMENTAL HEALTH
Caring for the Environment in
the Interests of World Health
Co - s p o n s o rs o f t h e En v iro n m e n t a l Ma n a g e m e n t & He a lt h I n t e rn e t Re s e a rc h Re g is t e r
Th e "En v ir o n m e n t a l Ma n a g e m e n t a n d He a lt h " ( EMH) In t e rn e t Re s e a rch Re g is t e r re p o rt s o n
cu rre n t re s e a rch wo rld wid e , in clu d in g s t u d ie s co m p le t e d d u rin g t h e p a s t s ix t o n in e m o n t h s .
Re s e a rch m a y b e lin ke d t o a n a ca d e m ic co u rs e o f s t u d y o r p ro je ct , b e in d e p e n d e n t , o r
o rg a n is a t io n - b a s e d . Bo t h in d u s t ry a n d t h e a ca d e m ic wo rld a re re p re s e n t e d , a s we ll a s t h e
g o ve rn m e n t a n d NGO s e ct o rs . Th e re g is t e r a im s t o b e co m p re h e n s ive in it s g e o g ra p h ic a n d
http://www.mcbup.com/research_registers/emh/sponsors.asp (1 of 2) [04/10/2000 1:05:58 PM]
Sponsors
s u b je ct co ve ra g e a n d a im s t o m a in t a in a s o u n d b a la n ce b e t we e n t h e o ry a n d p ra ct ice . En t rie s
wh ich re p o rt o n a p p lie d re s e a rch a re p a rt icu la rly we lco m e .
Th e Re g is t e r in clu d e s , b u t is n o t re s t rict e d , t o re s e a rch in t h e fo llo win g a re a s o f e n viro n m e n t a l
m a n a g e m e n t a n d e n viro n m e n t a l h e a lt h : g e n e ra l e n v iro n m e n t a l m a n a g e m e n t ; e n v iro n m e n t a l
p o licie s a n d le g is la t io n ; in d u s t ria l e n v iro n m e n t a l p ra ct ice s a n d p ro ce s s e s ; e n v iro n m e n t a l h e a lt h ;
a p p lie d t ra in in g in e n v iro n m e n t a l m a n a g e m e n t ; e n v iro n m e n t a l m a n a g e m e n t s y s t e m s ; s u s t a in a b le
d e v e lo p m e n t , la n d u s e a n d p la n n in g ; w a s t e s m a n a g e m e n t ; e n e rg y a n d it s u s e ; w a t e r, w a t e r u s e ,
w a s t e w a t e r a n d w a t e r m a n a g e m e n t ; d is e a s e s a n d illn e s s e s d e riv in g fro m e n v iro n m e n t a l
p ro b le m s ; a s p e ct s o f e n v iro n m e n t a l m a n a g e m e n t a n d la w .
Th e b e n e fit s o f re g is t e rin g y o u r re s e a rc h : Th e EMH In t e rn e t Re s e a rch Re g is t e r p ro vid e s t h e
re s e a rch co m m u n it y wit h p re - p u b lica t io n in fo rm a t io n a n d t h e p o t e n t ia l fo r fu rt h e r n e t wo rkin g ,
a lo n g s id e e a rly in fo rm a t io n o n n e w a re a s fo r a p p lica t io n a n d d e ve lo p m e n t in t h e fie ld . It a ls o
a llo ws t h e re s e a rch e r t o :
*
*
*
*
*
*
*
p ro m o t e t h e ir o wn re s e a rch a n d t h a t o f t h e ir o rg a n is a t io n / in s t it u t io n ;
e n s u re t h a t t h e y a re n o t d u p lica t in g re s e a rch t h a t is a lre a d y u n d e rwa y;
id e n t ify p o s s ib le re s e a rch m e t h o d o lo g ie s ;
id e n t ify p e e rs fo r co lla b o ra t ive re s e a rch p ro je ct s ;
id e n t ify p o s s ib le s o u rce s o f fu n d in g fo r re s e a rch ;
id e n t ify t yp e s o f re s e a rch u n d e rwa y, e . g . t h e o re t ica l, a p p lie d re s e a rch , ca s e s t u d y;
id e n t ify a re a s wh e re fu rt h e r re s e a rch is re q u ire d .
Th e EMH In t e rn e t Re s e a rch Re g is t e r is fre e ly a va ila b le t o a ll wh o re g is t e r t h e ir re s e a rch , t o
s u b s crib e rs t o t h e a b o ve jo u rn a ls a n d t o m e m b e rs o f a s s o cia t e d o rg a n is a t io n s / in s t it u t e s . Ple a s e
co n t a ct Je n n y Pickle s : jp ickle s @m cb . co . u k fo r d e t a ils o f h o w yo u r a s s o cia t io n ca n g a in fr e e
a cce s s .
All e n t rie s a re va lid a t e d b y Pro f. Wa lt e r Le a l Filh o , Te ch n ica l Un ive rs it y Ha m b u rg - Ha rb u rg
Te ch n o lo g y Tra n s fe r ( TUHH/ Tu Te ch ) , Ge rm a n y a n d t h e Ro ya l In s t it u t e o f Te ch n o lo g y, S t o ckh o lm ,
S we d e n .
No re s p o n s ib ilit y is a cce p t e d fo r t h e a ccu ra cy o f in fo rm a t io n co n t a in e d in t h e re s e a rch p re s e n t e d wit h in t h is Re g is t e r. Th e o p in io n s
e xp re s s e d h e re in a re n o t n e ce s s a rily t h o s e o f t h e Ed it o rs o r t h e p u b lis h e r.
© MCB Un iv e rs it y Pre s s , UK a n d Th o m a s Te ch n o lo g y S o lu t io n s ( UK) Lt d .
[ S e a rch ] [ Ad va n ce d S e a rch ] [ S u b m it Re s e a rch ] [ Ed it Re s e a rch ] [ He lp ]
http://www.mcbup.com/research_registers/emh/sponsors.asp (2 of 2) [04/10/2000 1:05:58 PM]
http://www.mcbup.com/research_registers/emh.asp
The current issue and full text archive of this journal is available at
http://www.emerald-library.com
Risk assessment of
radiation-induced thyroid
cancers in Belarus
Mikhail V. Malko
Radiationinduced thyroid
cancers
455
Institute of Radiation Physical and Chemical Problems,
National Academy of Sciences of Belarus, Minsk,
Republic of Belarus
Keywords Risk, Radiation, Belarus
Abstract The paper presents results of a qualitative assessment of the morbidity and mortality
in thyroid cancers by the Belarusian population caused by the Chernobyl accident. In the period of
1986-1998 about 3,851 radiation-induced thyroid cancers appeared in Belarus: about 615
cancers by children and about 3,236 cancers by adolescents and adults. The number of lethal
thyroid cancers in this period of time in Belarus is assessed as about 167 cases. The excessive
absolute risk (EAR) of the morbidity in the thyroid cancer assessed for the period of 1986-1998
on the basis of given data on the morbidity is about 1.7 per 104 PYGy. The excessive absolute risk
of mortality is assessed as about 0.075 per 104 PYGy. These values agree quite well with
analogous risk coefficients established for other groups of people in other epidemiological studies.
Introduction
As a result of the Chernobyl accident a large amount of radioactive substances
escaped from the destroyed reactor. Especially high release was in the case of
volatile radionuclides. So according to the existing assessments about 50-60 per
cent of the 131I isotope inventory came into the environment (GuÈntay et al., 1997).
This caused the radioactive contamination of many countries of the Northern
Hemisphere. However, Belarus was affected by the accident most of all.
Practically the whole territory of Belarus was contaminated with different
radionuclides (Matveenko et al., 1997). This resulted in irradiation of the whole
Belarusian population. In the early stage of the accident the radiation situation
was determined mostly by short-lived radionuclides. A very important role at
this time was played by iodine isotopes. They caused irradiation of thyroid
glands of children, adolescents and adults of the whole Belarus. However, the
highest doses to the thyroid glands were delivered to inhabitants of Gomel and
Brest oblasts (regions). For example, the arithmetic mean thyroid dose in the age
group 0-6 years by children living in settlements settled in the 30km zone was
about 4.7 Gy and maximal doses were about 50Gy (Gavrilin et al., 1999). For
inhabitants of this settlement aged 7-17 years at the moment of the accident the
thyroid dose was about 2.1Gy and for adults about 1.6Gy. The extensive
irradiation of the thyroid gland by the Belarusian population caused very soon
after the accident a significant increase in the incidence in thyroid cancers. This
effect was especially very pronounced for children, who are more sensitive to
irradiation and that received much higher doses than adolescents and adults.
Environmental Management and
Health, Vol. 11 No. 5, 2000,
pp. 455-467. # MCB University
Press, 0956-6163
EMH
11,5
456
The first reliable data on a sharp increase in the thyroid cancer morbidity by
children of Belarus after the Chernobyl accident were published in 1992
(Kazakov et al., 1992). However, specialists met these data with great
scepticism (Ron et al., 1992). There were serious reasons for this scepticism.
First, the published data on the incidence of thyroid cancers have shown an
unusual short latent period of about two to three years. Second, no similar data
about the increase in the incidence of thyroid cancer by children of the affected
areas of the Ukraine and Russia were known at that time. And this was very
strange because all specialists believed that the Ukraine was affected by the
Chernobyl accident much more than Belarus. It is now clear that such
assumption was totally incorrect.
In order to explain an unusually high incidence of thyroid cancer in the
children of Belarus some specialists proposed the idea that this increase was
caused by the improved screening in Belarus (Ron et al., 1992).
This situation changed only after the first international conference on the
radiological consequences of the Chernobyl accident held in Minsk in 1996 from
18-22 March. At the conference new data on the thyroid cancer incidence in
Belarus (Demidchik et al., 1996a) as well as similar data on the increase in the
thyroid cancer incidence by children of the Ukraine (Tronko et al., 1996) and
Russia (Tsyb et al., 1996) were presented. Data on the thyroid cancer morbidity
by children of these two countries differed only quantitatively from the
Belarusian data.
At the Minske conference an amount of evidence was given which shows
that the increase in the incidence of thyroid cancer in the children and
adolescents of Belarus, the Ukraine and Russia had its origins in radiation.
So it was shown that, in Belarus, thyroid cancer has mainly appeared in
children irradiated as a result of the Chernobyl accident. Out of the total
number of 390 thyroid cancers registered by children of Belarus in 1986-1994
and first seven months of 1995, 380 cases were diagnosed by children born
before the Chernobyl accident, six cases by children born at the time of the
accident and only four cases by children born after full disintegration of
radioiodine (Demidchik et al., 1996a). Another very important finding relates to
the histological types of thyroid cancers in countries affected by the Chernobyl
accident. For instance, more than 90 per cent of thyroid cancers in Belarus and
the Ukraine were papillary carcinoma as compared with 68 per cent in England
and Wales (Williams et al., 1996). Within the papillary carcinoma, over 70 per
cent of thyroid cancers in the countries affected by the Chernobyl accident were
of the solid follicular type, compared to only 40 per cent in England and Wales.
At present practically all specialists are sure that the sharp increase in the
incidence in thyroid cancer established by the children of Belarus, the Ukraine
and Russia after the Chernobyl accident has its origins in the radiation.
It is noticeable here that many specialists, especially in Western countries
believe that besides radiation-induced thyroid cancers in the children of Belarus,
the Ukraine and Russia no other medical effect was caused by the Chernobyl
accident in these countries. Such an assumption is incorrect, at least for Belarus
where an increase in the incidence of thyroid cancer in adolescents and adults
was also registered after the accident. Existing assessment (Malko, 1998a) shows
that in the period 1986-1997 about 2,708 additional thyroid cancers were manifest
in adolescents and adults of Belarus in comparison with 562 cases of children. As
can be seen from these data the number of additional thyroid cancers manifest in
adolescents and adults of Belarus in the period 1986-1997 is five times higher
than that for children. This fact indicates that assessment of the real harm of a
radiological accident of the scale of the Chernobyl accident requires consideration
of all irradiated groups of the affected population.
One of the tasks of this report is the assessment of the total number of
additional thyroid cancers manifest in Belarus in the period 1986-1998, as well
as finding arguments that show a positive association between these additional
thyroid cancers and irradiation of people as a result of the Chernobyl accident.
It seems that assessment of the excessive absolute risk (EAR) of the
radiation-induced thyroid cancer can provide such arguments. This task is
solved on the basis of data established in Belarus because the population of this
country received the highest thyroid doses (Malko, 1998b). Due to this fact a
clearer manifestation of the irradiation effects may be expected in Belarus. It is
also important that the epidemiological data established in Belarus are more
comprehensive and accurate than in Russia and the Ukraine.
Materials and method
Assessment of the morbidity in thyroid cancers by children, adolescents and
adults of Belarus after the Chernobyl accident was carried out on the basis of
published data of the Scientific Center for Thyroid Cancer of Belarus
(Demidchik et al., 1996a; 1996b; Demidchik, 1998; Demidchik, 2000) as well as
published data of the Belarusian Cancer Registry (1999).
These centers collect all information about thyroid cancers in children,
adolescents and adults registered in all regions of Belarus. This monitoring of
the manifestation of thyroid cancers was carried out from the 1960s.
Analysis of publications of the Scientific Center for Thyroid Cancer of
Belarus and of the Belarusian Cancer Registry shows that they give practically
the same data on the incidence of thyroid cancers in children, adolescents and
adults of Belarus. The only one difference is that the Center publishes the
absolute numbers of thyroid cancers and the Registry gives the crude incidence
rates as well as age standardized morbidity rates. The Registry gives also
information about mortality from thyroid and other cancers.
The excessive absolute risk was assessed in the paper on the basis of the
following expression:
EAR O ÿ E c= Hcoll n;
where:
O = observed number of cases;
E = expected or spontaneous number of cases;
1
Radiationinduced thyroid
cancers
457
EMH
11,5
458
c
= coefficient allowing for the screening effect;
coll
H = collective dose of the thyroid gland irradiation;
n = number of years under observation.
The value of the coefficient c in the present work was taken equal to 1 because
no correct information about a contribution of the screening effect to the
incidence in thyroid cancers by children, adolescents and adults of Belarus
before and after the Chernobyl accident is known.
In the case of children, as an expected number of thyroid cancers, 1 case per
year was taken as follows from data of the Belarusian Thyroid Cancer Center
(Demidchik et al., 1996b). So according to these data in 1966-1985 (or during 20
years before the Chernobyl accident) only 21 cases of thyroid cancer were
registered by children of Belarus. This gives one case of thyroid cancer per year
as a spontaneous morbidity in the thyroid cancer for the Belarusian children.
The average number of children (less than 15 years old) in Belarus in the preaccidental period was about 2.5 million (Public Health, 1997). As can be
calculated from this figure the spontaneous morbidity in thyroid cancer by
children of Belarus before the Chernobyl accident was approximately 0.4 cases
per million. This value is very close to the spontaneous morbidity in thyroid
cancer in children of England and Wales (Williams et al., 1966), that is
approximately 0.5 cases per million.
The expected numbers of thyroid cancers in adolescents and adults of
Belarus were assessed on the basis of the formula (Malko, 1998a):
Ej E0 : 1 aj ;
2
Here:
E0 = spontaneous morbidity of adolescents and adults in 1977 (121
cases);
a = is a constant showing the annual increase in the incidence of the
thyroid cancer, it is about 0.2 (2 per cent increase annually);
j = is a number of the consequent year beginning with j = 0 for 1977
(j = 1 for 1978 and so on);
Ej = spontaneous morbidity of adolescents and adults in the jth year.
The last expression was established by using observed incidence in thyroid
cancers by adolescents and adults of Belarus before the Chernobyl accident
(Demidchik et al., 1996a). In the present paper it was used for calculation of
expected thyroid cancers in this group of population after the Chernobyl
accident. Results of calculation together with observed data (Demidchik et al.,
1996a) are presented in Table I. Here are also given observed and expected
numbers of thyroid cancers by children of Belarus in 1977-1985.
As can be seen from Table I, observed (Demidchik et al., 1996a) and expected
numbers of thyroid cancers in children, adolescents and adults of Belarus in
Children
Observed
Expected
Year
1977
1978
1979
1980
1981
1982
1983
1984
1985
Total
2
2
0
0
1
1
0
0
1
7
Adolescents and adults
Observed
Expected
Corrected
1
1
1
1
1
1
1
1
1
9
121
97
101
127
132
131
136
139
148
1,131
121
123
126
128
131
134
136
139
142
1,180
121
123
126
127
132
131
136
139
148
1,182
Radiationinduced thyroid
cancers
459
Table I.
Thyroid cancer in
Belarus before the
Chernobyl accident
1977-1985 tally quite well. For example, the difference between numbers of
observed (1,131 cases) and expected (1,180) thyroid cancers in adolescents and
adults of Belarus in this period of time is only 49 cases or about 4.3 per cent.
This means that our assumption about the spontaneous morbidity of thyroid
cancer in Belarus before the Chernobyl accident is quite correct. Data in this
table show that the largest difference in observed and expected numbers of the
thyroid cancer in the case of adolescents and adults took place in 1978 and
1979. It is about 25 per cent. It resulted possibly from underestimation of
observed thyroid cancers in 1978 and 1979. By using for these years data
calculated with the expression (2) as observed data, the difference in total
amounts of observed and expected numbers of thyroid cancers manifest in
adolescents and adults in the period 1977-1985 decreased by up to 0.16 per cent.
Observed numbers of thyroid cancers in adolescents and adults of Belarus
corrected in this way are given in the sixth column of Table I.
Results and discussion
Table II and Figure 1 show observed data (Demidchik, 1998) on the thyroid
cancer morbidity of children of Belarus after the Chernobyl accident. Data in
Table II demonstrates an increase in the incidence of the thyroid cancer
manifest in children of all regions of Belarus. However, the largest increase
Region
Brest
Vitebsk
Gomel
Grodno
Minsk
Mogilev
Minsk-city
Belarus total
Year
1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 Cases
0
0
1
1
0
0
0
2
0
0
2
1
1
0
0
4
1
0
1
1
1
0
1
5
1
0
3
2
1
0
0
7
7
1
14
0
1
2
4
29
5
3
43
2
1
3
2
59
17
2
34
4
4
1
4
66
24
0
36
3
4
7
5
79
21
1
44
5
6
4
1
82
21
0
48
5
1
6
10
91
25
0
42
5
5
3
4
84
13
0
37
3
6
4
3
66
135
7
305
32
31
30
34
574
Table II.
Thyroid cancer in
children of Belarus
after the Chernobyl
accident
EMH
11,5
460
Figure 1.
Dynamics in the thyroid
cancer incidence in
children of Belarus after
the Chernobyl accident
appeared in the Gomel and Brest regions. The geographical distribution of
thyroid cancers by Belarusian children correlates with levels of contamination
by 131I isotope in Belarus (Matveenko et al., 1997).
The summary data from Table II were also used to construct Figure 1, which
shows the temporary trend in the thyroid cancer incidence in children of
Belarus in the time from 1986 up to 2004. Here numbers of thyroid cancers
registered by children in 1986-1999 (Demidchik et al., 1996a; Demidchik, 1998;
2000) and data forecast for 2000-2004 are presented.
As can be seen from Table II and Figure 1, the incidence of thyroid cancer in
children of Belarus reached the maximum in 1995 and then began to decrease.
The reason for this decline is very easily explained. It was explained on the
basis of a transition model (Malko, 1998a). All official data on the cancer
morbidity in Belarus are given for two groups. The first group includes data for
those people for which any cancer, as well as the thyroid cancer, was diagnosed
when they were less than 15 years old. The second group includes all people
who are older than 15 years. Thus, when a person reaches 15 years at the time
of the thyroid cancer diagnosis this person will be considered as a person
belonging to the group of adolescents and adults. This means that the observed
decline in the morbidity in thyroid cancer in children of Belarus originates from
the method of medical registration used in Belarus.
The last children with thyroid glands irradiated as a result of the Chernobyl
accident will pass into the category of adolescents and adults in 2001. To this
group belong children irradiated in-utero and born some months after the
explosion of the Chernobyl reactor. Thus the incidence of thyroid cancer in
children of Belarus in 2002 has to change to the spontaneous rate that was
assessed in this paper as one case per year for the whole of Belarus.
By forecasting of numbers of thyroid cancers for 2000-2004 the following
simplified procedure was used. A total 54 cases of thyroid cancers in 1998 and
49 in 1999 by children of Belarus were registered (Demidchik, 2000). Linear
extrapolation between 49 cases in 1999 and one case in 2002 gives for the years
2000 and 2001, 32 and 16 thyroid cancers respectively. The total number of
thyroid cancers in the Belarusian children that can manifest in the period from
1986 up to 2002 will be then equal to 725 cases. Subtracting from this number
the number of spontaneous thyroid cancers that have to appear in 1986-2001
(15 cases) will give the total number of thyroid cancers in children of Belarus
that will be caused as a result of the Chernobyl accident, equal to
approximately 710 cases.
Data on the number of thyroid cancers registered by adolescents and
adults of Belarus in 1986-1997 given in the second column of Table III were
taken from the report (Demidchik, 1998). The number of thyroid cancers in
this column for 1998 were calculated on the basis of the morbidity rate
(Belarusian Cancer Registry, 1999) of thyroid cancer of the whole Belarusian
population.
According to report of the Belarusian Cancer Registry (1999) this rate was 7.5
cases per 100,000 people in 1998 and the total number of people in Belarus was
10.2 million. By using these data one can calculate the total number of thyroid
cancers registered in Belarus in 1998 as being equal to 765 cases. This number
is a sum of thyroid cancers established by children and adolescents and adults.
Subtraction of the number of children's cancers (54 cases in 1998) from this
value gives 711 cases as a number of thyroid cancers registered in 1998 by
adolescents and adults. This number is shown in Table III.
The third column of Table III gives numbers of spontaneous thyroid cancers in
1986-1998 calculated by using the expression (2). The fourth column of this
table presents the numbers of additional thyroid cancers manifest in
Year
Observed
Expected
Observedexpected
Sir
95 per cent CI
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
Total
162
202
207
226
289
340
416
512
553
531
568
641
711
5,358
145
147
150
153
157
160
163
166
169
173
176
180
183
2,122
17
55
57
73
132
180
253
346
384
358
392
461
528
3,236
1.12
1.37
1.38
1.48
1.84
2.13
2.55
3.08
3.27
3.07
3.23
3.56
3.89
2.52
0.95-1.30
1.19-1.57
1.20-1.58
1.29-1.68
1.64-2.06
1.91-2.36
2.31-2.81
2.83-3.36
3.01-3.56
2.82-3.34
2.97-3.51
3.29-3.85
3.61-4.18
2.46-2.59
Radiationinduced thyroid
cancers
461
Table III.
Thyroid cancer in
adolescents and adults
of Belarus after the
Chernobyl accident
EMH
11,5
462
adolescents and adults of Belarus in this period. The fifth column shows the
standardized incidence ratio and the sixth column gives the confidence
intervals estimated for SIR on the basis of the Poisson distribution.
The data of Table III show that the incidence of thyroid cancer in
adolescents and adults of Belarus increased after the Chernobyl accident at
least by a factor of two to three in comparison with the incidence before the
accident. This increase resulted in the number of additional thyroid cancers
equal to 3,236 cases. It is clear that the accuracy in the assessment of additional
thyroid cancers depends very strongly on the accuracy in determination of the
background morbidity before the Chernobyl accident, because the background
morbidity in this period of time is used in the present paper for assessment of
expected thyroid cancers after the accident. It is also evident that
underestimation of the morbidity in thyroid cancers will be important only
when after the accident a significant improvement in screening has taken place.
This effect or the effect of improved screening is especially important in case of
adolescents and adults because of a rather elevated increase in the incidence of
thyroid cancers in this group of population after the Chernobyl accident. The
effect of improved screening is not so important in the case of children because
of a very large increase in the incidence in thyroid cancers by them.
Unfortunately, at the present time there is no such information for Belarus
that could be helpful by answering the question what contribution to the
assessed numbers of additional thyroid cancers by adolescents and adults gave
the effect of improving in screening after the Chernobyl accident. However, it
seems unreasonable to explain the evident increase in the incidence of thyroid
cancers in adolescents and adults of Belarus after the accident exceptionally on
the basis of the idea of improved screening. At least partly this increase has to
be a real effect because of the transition from the group of children into the
group of adolescents and adults. It should also be noticed here that a marked
increase in the incidence of thyroid cancers in adolescents and adults was
registered in 1987-1989, when there was no necessity for radical improvement
of medical screening in Belarus. It is well known that in the former USSR only
some areas in the northern Ukraine were considered as affected by the accident
during the first three years after the accident. The first official and realistic
information about radiological problems of Belarus caused by the Chernobyl
accident appeared only three years after the accident. This was the time of
aggravation of the economic situation in Belarus as well as in the whole USSR.
So there was also no economic base for a significant improvement in screening
of thyroid cancer in Belarus at all. Relating this problem, one needs also to
notice that the incidence of the thyroid cancer in Belarus before the Chernobyl
accident was practically the same as in some counties of the UK and in some
other European countries. Calculation on the basis of corrected observed
numbers of thyroid cancers (see the sixth column of Table I) gives, for the
period 1978-1982, the mean age standardized (world standard) value of the
morbidity rate of thyroid cancer for Belarusian population equal to 1.1 per
100,000 people. Practically the same standardized values were determined in
1978-1982 in different counties of the UK, as well as in different areas of Poland,
Romania and other European countries. This agreement shows that the level of
medical screening in Belarus before the Chernobyl accident was the same as in
other European countries. Thus it is unreasonable to believe that the increase in
the incidence of thyroid cancers in Belarus in the period 1986-1998 results from
the improvement in the screening.
The total number of additional thyroid cancers in children, adolescents and
adults of Belarus in 1986-1998 calculated on the basis of the data discussed
above is equal to 3,851 cases. The collective thyroid dose of the Belarusian
population according to the assessment (Malko, 1998b) is about 12.7105
manSv. By this assessment a conversion coefficient 0.72Sv/Gy was used.
Considering this fact one can calculate the collective thyroid dose of the
Belarusian population also as 17.6105 man.Gy. Inserting this value and the
number of additional thyroid cancers that was assessed in this work (3,851
cases) into the expression (1) one can estimate the EAR of the radiation-induced
thyroid cancers caused in Belarus by the Chernobyl accident as being equal to
1.7 per 104 PYGy.
This value tallies completely with the excessive absolute risk of radiationinduced thyroid cancer that was established for the period 1990-1997 for those
inhabitants of the city Kiev and Ukrainian regions closest to the Chernobyl
NPP (Chernigov, Kiev and Zhytomir regions) that were 0-18 years old at the
time of the Chernobyl accident (Likhtarev et al., 1999). In 1997 they were 11-31
years old. For this fraction of the affected Ukrainian population the value of the
EAR equal to 1.7 per 104PYGy was established.
The EAR value that was assessed in the present work agrees also very well
with EARs established in other studies. For example, the value of EAR that
was established for the period 1958-1987 by atomic bomb survivors is 1.6 per
104 PYSv with 95 per cent CI 0.78-2.5 per 104 PYSv. By transforming to other
units these values gives the EAR equal to 1.1 per 104 PYGy ( 95 per cent CI =
0.55 ± 1.75). In the study of inhabitants of the Marshall Islands that had a
strong internal irradiation of the thyroid gland with 131I the EAR was
estimated as 1.1 per 104 PYGy (Robbins and Adams, 1989). Study of
consequences of the Utah 131I fallout (Kerber et al., 1993) gave the value of EAR
equal to 3.3 per 104PYGy. According to the pooled analysis of Ron et al. (1995),
the excessive absolute risk of the acute external irradiation of thyroid glands
by people aged less than 20 is 4.4 per 104 PYGy (95 per cent CI = 1.9 ± 10).
Agreement between the values of EAR established in this and other works
permits a number of conclusions, which are the following. First, one can believe
that the number of additional thyroid cancers that was assessed in this work is
quite reasonable. It means that, in the period of time 1986-1998, in Belarus
about 615 radiation-induced thyroid cancers appeared in children and about
3,236 thyroid cancers in adolescents and adults. Second, this agreement reveals
the correctness of the assessed collective thyroid dose of the Belarusian
population (Malko, 1998b) used in the present paper by estimation of the
excessive absolute risk. It is clear that a reasonable value of the excessive
Radiationinduced thyroid
cancers
463
EMH
11,5
464
Figure 2.
Mortality rate in Belarus
from the thyroid cancer
after the Chernobyl
accident
absolute risk can be achieved only in case of having quite accurate data on the
numbers of radiation-induced cancers and on the collective thyroid dose of the
irradiated group of people. Third, the early manifestation of radiation-induced
thyroid cancers in Belarus shows clearly that the latent period of the thyroid
cancer, at least in Belarus, is less than five years. This is not surprising. Such a
possibility was forecast a long time ago (Gofman, 1981). It was proposed that
the latent period of any cancer had to depend on the number of people in the
group under study. In the case of a small group a very long time can be needed
in order to get a provable difference within a control group. By contrast, in the
case of a very large group of irradiated people, the provable difference can be
reached in a very short time. Such a situation is realized in Belarus where
thyroid glands of approximately 10,000,000 people were irradiated.
The similar procedure as in the case of the thyroid cancer incidence can be
used for assessment of a number of people in Belarus that died from the thyroid
cancer caused by the Chernobyl accident.
Figure 2 shows the dynamic in the crude mortality rate resulting from the
morbidity in thyroid cancers. These data were taken from reports of the
Belarusian Cancer Registry (Public Health Ministry of the Republic of Belarus,
1997; Tsyb et al., 1996; Williams et al., 1996). They give the mortality in thyroid
cancers of the whole Belarusian population (children, adolescents and adults).
The upper (solid) line gives the observed mortality rates. The lower (dotted)
line shows the ``spontaneous'' mortality rates as determined by us. Using these
data as well as data on a number of people in Belarus in 1986-1998 (it is about
10 million people) gave approximately 167 fatal cases resulting from the
radiation-induced thyroid cancers for this period of time.
The excessive absolute risk of mortality resulting from the radiation-induced
thyroid cancers calculated on the basis of this number and the collective
thyroid dose of the Belarusian population is equal to 0.075 per 104 PYGy. This
value is comparable with the excessive absolute risk of mortality from
radiation thyroid cancers by atomic bomb survivors. For this cohort of people
the value of EAR equal to 0.016 per 104 PYSv (95 per cent CI = ±0.04 ± 0.24) was
estimated for the period 1950-1987 (Ron et al., 1994). In other units the excessive
absolute risk of mortality by atomic bomb survivors is 0.011 per 104 PYGy (95
per cent CI= ± 0.028 ± 0.168). As can be seen from these data, there is an
overlapping in values of the excessive absolute risks of mortality from
radiation-induced thyroid cancers estimated in the present paper and by atomic
bomb survivors. This permits the conclusion that the number of people who
have already died in Belarus from radiation-induced thyroid cancers caused by
the Chernobyl accident is assessed in the present paper quite correctly.
Conclusions
.
The morbidity and mortality from radiation-induced cancers in Belarus
as a result of the Chernobyl accident has been assessed for the period of
time 1986-1998. According to this assessment about 615 radiationinduced thyroid cancers in the children of Belarus appeared in 19861998. The total number of children's thyroid cancers that will manifest
in 1986-2001 can be about 710 cases. The number of the radiationinduced thyroid cancers manifested by adolescents and adults of
Belarus in 1986-1998 as a result of the Chernobyl accident was assessed
as approximately 3,236 cases. The total number of radiation-induced
thyroid cancers appearing in this period of time is about 3,851 cases. The
number of people that died in Belarus in 1986-1998 from radiationinduced cancer was assessed as about 167 cases.
.
The excessive absolute risk, EAR, of the radiation-induced thyroid
cancers manifested in Belarus after the Chernobyl accident is assessed
as 1.7 per 104 PYGy. This value agrees with EARs established in other
studies of the morbidity in thyroid cancers as a result of irradiation.
.
The excessive absolute risk of mortality in Belarus in 1986-1998 from
the radiation-induced thyroid cancers was assessed as 0.075 per 104
PYGy in accordance with data established in other studies.
References
Belarusian Cancer Registry (1999), ``Malignant neoplasms in Belarus: 1989-1998''.
Demidchik, E.P. (1998), ``Epidemiology and surgery of thyroid carcinom'', report at the annual
meeting of the German Societies of the Radiation Studies, 16-18 March, FRG, Munich.
Demidchik, E.P. (2000), Private communication.
Demidchik, E.P., Drobyshevskaya, I.M., Cherstvoy, E.D., Astakhova, L.N., Okeanov, A.E.,
Vorontsova, T.V. and Germenchuk, M. (1996a), ``Thyroid cancer in children in Belarus'', in
Karaoglou, A., Desmet, G., Kelly, G.N. and Menzel, H.G. (Eds), Proceedings of the First
Radiationinduced thyroid
cancers
465
EMH
11,5
466
International Conference ``The Radiological Consequences of the Chernobyl Accident'', held
in Minsk, Belarus, 18-22 March, EUR 16544 EN, Brussels-Luxembourg, pp. 677-82.
Demidchik, E.P., Okeanov, A.E., Rebeko, V.Y. and Demidchik, Y.E. (1996b), ``Current trend in
prophylaxies, early diagnosis, and curative treatment of thyroid cancer in Belarus'', in
Takeichi, N., Satow, Y. and Masterson, R.H. (Eds), The Chernobyl Accident. Thyroid
Abnormalities in Children, Congenital Abnormalities and Other Radiation Related
Information. The First Ten Years, 1st ed., Hirosima-Nagasaki Peace Foundation, Japan,
pp. 89-93.
Gavrilin, Y.I., Krouch, V.T., Shinkarev, S.M., Krysenko, N.A., Skryabin, A.M., Bouville, A. and
Anspaugh, L.R. (1999), ``Chernobyl accident: reconstruction of thyroid dose for inhabitants
of the Republic Belarus'', Health Physics, Vol. 76 No. 2, pp. 105-19.
Gofman, J.W. (1981), Radiation and Human Health. A Comprehensive Investigation of the
Evidence Relating Low-level Radiation to Cancer and Other Diseases, Sierra Club Books,
San Francisco, CA, pp. 103-9
GuÈntay, S., Powers, D.A. and Devell, L. (1997), ``The Chernobyl reactor accident source term:
development of a consensus view'', Proceedings of the International Conference ``One
Decade after Chernobyl: Summing up the Consequences of the Accident'', Vol. 2, held in
Vienna, 8-12 April 1996, IAEA, Vienna, Poster presentation, pp. 183-93.
Kazakov, V.S., Demidchik, E.P. and Astakhova, L.N. (1992), ``Thyroid cancer after Chernobyl'',
Nature, Vol. 359, p. 21.
Kerber, R.A., Till, J.E., Simon, S.L., Thomas, D.C., Preston-Martin, S., Rallison, M.L., Lloid, R.D.
and Stevens, W. (1993), ``A cohort study of thyroid disease in relation to fallout from
nuclear weapon testing'', Journal of the American Medical Association, Vol. 270, pp. 207682.
Likhtarev, I.A., Kayro, I.A., Shpak, V.M., Tronko, N.D and Bogdanova, T.I. (1999), ``Radiationinduced and background thyroid cancer of Ukrainian children'', Int. J. Radiat. Med., No. 3-4,
pp. 51-66.
Malko M.V. (1998a), ``Thyroid cancer in Belarus'', in The Radiological Catastrophe in Chernobyl:
Report of the International Study (in Japanese), Tokyo, Japan, pp. 218-22.
Malko, M.V. (1998b), ``Assessment of the Chernobyl radiological consequences'', in Imanaka, T.
(Ed.), Research Activities about Radiological Consequences of the Chernobyl NPS Accident
and Social Activities to Assist the Sufferers by the Accident, Research Reactor Institute,
Kyoto University, Japan, pp. 65-89.
Matveenko, I.I., Germenchuk, M.G., Shagalova, E.D. and Zhukova, O.M. (1997), ``Migration and
forecast of the radioactive contamination of the soil, water and air on the territory of
Belarus after the accident at the Chernobyl NPP'', Proceedings of the International
Conference ``One Decade after Chernobyl: Summing up the Consequences of the Accident'',
Vol. 2, held in Vienna, 8-12 April 1996, IAEA, Vienna, Poster presentation, pp. 64-70.
Public Health Ministry of the Republic Belarus. Medical Statistics Department (1997), Public
Health in the Republic of Belarus. An Official Statistics Collection (in Russian), Public
Health Ministry of the Republic Belarus. Medical Statistics Department, Minsk, p. 30.
Robbins, J. and Adams, W. (1989), ``Radiation effects in the Marshall Islands'', in Nagataki S.
(Ed.), Radiation and the Thyroid, Excerpta Medica, Amsterdam, pp. 11-24.
Ron, E., Lubin, J. and Schneider, A. (1992), ``Thyroid cancer incidence'', Nature, Vol. 360, p. 113.
Ron, E., Lubin, J.H., Shore, R.E., Mabuchi, K., Modan, B., Pottern, L.M., Schneider, A.B., Tucker,
M.A. and Boice, J.D. (1995), ``Thyroid cancer after exposure to external radiation: a pooled
analysis of seven studies'', Radiation Res., Vol. 141, pp. 259-77.
Tronko, N., Bogdanova, T., Komissarenko, I., Bolshova, E., Oleinik, V., Tereshchenko, V.,
Epshtein, Y. and Chebotarev, V. (1996), ``Thyroid cancer in children and adolescents in
Ukraine after the Chernobyl accident (1986-1995)'', in Karaoglou, A., Desmet, G., Kelly,
G.N. and Menzel, H.G. (Eds), Proceedings of the First International Conference ``The
Radiological Consequences of the Chernobyl Accident'', held in Minsk, Belarus, 18-22 March,
EUR 16544 EN, Brussels-Luxembourg, pp. 683-90.
Tsyb, A.F., Parshin, E.M., Shakhtarin, V.V., Stepanenko, V.F., Skvortsov, V.F. and Chebotareva,
I.V. (1996), ``Thyroid cancer in children and adolescents of Bryansk and Kaluga regions'',
in Karaoglou, A., Desmet, G., Kelly, G.N. and Menzel, H.G. (Eds), Proceedings of the First
International Conference ``The Radiological Consequences of the Chernobyl Accident'', held
in Minsk, Belarus, 18-22 March, EUR 16544 EN, Brussels-Luxembourg, pp. 691-7.
Williams, E.D., Cherstvoy, E., Egloff, B., Holer, H., Vecchi, G., Bogdanova, T., Bragarnik, M. and
Tronko, N.D. (1996), ``Interaction of pathalogy and molecular characterization of thyroid
cancers'',in Karaoglou, A., Desmet, G., Kelly, G.N. and Menzel, H.G. (Eds), Proceedings of
the First International Conference ``The Radiological Consequences of the Chernobyl
Accident'', held in Minsk, Belarus, 18-22 March, EUR 16544 EN, Brussels-Luxembourg,
pp. 699-714.
Radiationinduced thyroid
cancers
467
Sponsors
[ S e a rch ] [ Ad va n ce d S e a rch ] [ S u b m it Re s e a rch ] [ Ed it Re s e a rch ] [ He lp ]
We lco m e t o t h e En viro n m e n t a l Ma n a g e m e n t & He a lt h In t e rn e t Re s e a rch Re g is t e r, d e live re d b y
MCB Un ive rs it y Pre s s in a s s o cia t io n wit h t h e I n t e r n a t io n a l Jo u r n a l o f S u s t a in a b ilit y in Hig h e r
Ed u c a t io n a n d t h e fo llo win g in t e rn a t io n a l b o d ie s : THE INTERNATIONAL FEDERATION
OF ENVIRONMENTAL HEALTH
Caring for the Environment in
the Interests of World Health
Co - s p o n s o rs o f t h e En v iro n m e n t a l Ma n a g e m e n t & He a lt h I n t e rn e t Re s e a rc h Re g is t e r
Th e "En v ir o n m e n t a l Ma n a g e m e n t a n d He a lt h " ( EMH) In t e rn e t Re s e a rch Re g is t e r re p o rt s o n
cu rre n t re s e a rch wo rld wid e , in clu d in g s t u d ie s co m p le t e d d u rin g t h e p a s t s ix t o n in e m o n t h s .
Re s e a rch m a y b e lin ke d t o a n a ca d e m ic co u rs e o f s t u d y o r p ro je ct , b e in d e p e n d e n t , o r
o rg a n is a t io n - b a s e d . Bo t h in d u s t ry a n d t h e a ca d e m ic wo rld a re re p re s e n t e d , a s we ll a s t h e
g o ve rn m e n t a n d NGO s e ct o rs . Th e re g is t e r a im s t o b e co m p re h e n s ive in it s g e o g ra p h ic a n d
http://www.mcbup.com/research_registers/emh/sponsors.asp (1 of 2) [04/10/2000 1:05:58 PM]
Sponsors
s u b je ct co ve ra g e a n d a im s t o m a in t a in a s o u n d b a la n ce b e t we e n t h e o ry a n d p ra ct ice . En t rie s
wh ich re p o rt o n a p p lie d re s e a rch a re p a rt icu la rly we lco m e .
Th e Re g is t e r in clu d e s , b u t is n o t re s t rict e d , t o re s e a rch in t h e fo llo win g a re a s o f e n viro n m e n t a l
m a n a g e m e n t a n d e n viro n m e n t a l h e a lt h : g e n e ra l e n v iro n m e n t a l m a n a g e m e n t ; e n v iro n m e n t a l
p o licie s a n d le g is la t io n ; in d u s t ria l e n v iro n m e n t a l p ra ct ice s a n d p ro ce s s e s ; e n v iro n m e n t a l h e a lt h ;
a p p lie d t ra in in g in e n v iro n m e n t a l m a n a g e m e n t ; e n v iro n m e n t a l m a n a g e m e n t s y s t e m s ; s u s t a in a b le
d e v e lo p m e n t , la n d u s e a n d p la n n in g ; w a s t e s m a n a g e m e n t ; e n e rg y a n d it s u s e ; w a t e r, w a t e r u s e ,
w a s t e w a t e r a n d w a t e r m a n a g e m e n t ; d is e a s e s a n d illn e s s e s d e riv in g fro m e n v iro n m e n t a l
p ro b le m s ; a s p e ct s o f e n v iro n m e n t a l m a n a g e m e n t a n d la w .
Th e b e n e fit s o f re g is t e rin g y o u r re s e a rc h : Th e EMH In t e rn e t Re s e a rch Re g is t e r p ro vid e s t h e
re s e a rch co m m u n it y wit h p re - p u b lica t io n in fo rm a t io n a n d t h e p o t e n t ia l fo r fu rt h e r n e t wo rkin g ,
a lo n g s id e e a rly in fo rm a t io n o n n e w a re a s fo r a p p lica t io n a n d d e ve lo p m e n t in t h e fie ld . It a ls o
a llo ws t h e re s e a rch e r t o :
*
*
*
*
*
*
*
p ro m o t e t h e ir o wn re s e a rch a n d t h a t o f t h e ir o rg a n is a t io n / in s t it u t io n ;
e n s u re t h a t t h e y a re n o t d u p lica t in g re s e a rch t h a t is a lre a d y u n d e rwa y;
id e n t ify p o s s ib le re s e a rch m e t h o d o lo g ie s ;
id e n t ify p e e rs fo r co lla b o ra t ive re s e a rch p ro je ct s ;
id e n t ify p o s s ib le s o u rce s o f fu n d in g fo r re s e a rch ;
id e n t ify t yp e s o f re s e a rch u n d e rwa y, e . g . t h e o re t ica l, a p p lie d re s e a rch , ca s e s t u d y;
id e n t ify a re a s wh e re fu rt h e r re s e a rch is re q u ire d .
Th e EMH In t e rn e t Re s e a rch Re g is t e r is fre e ly a va ila b le t o a ll wh o re g is t e r t h e ir re s e a rch , t o
s u b s crib e rs t o t h e a b o ve jo u rn a ls a n d t o m e m b e rs o f a s s o cia t e d o rg a n is a t io n s / in s t it u t e s . Ple a s e
co n t a ct Je n n y Pickle s : jp ickle s @m cb . co . u k fo r d e t a ils o f h o w yo u r a s s o cia t io n ca n g a in fr e e
a cce s s .
All e n t rie s a re va lid a t e d b y Pro f. Wa lt e r Le a l Filh o , Te ch n ica l Un ive rs it y Ha m b u rg - Ha rb u rg
Te ch n o lo g y Tra n s fe r ( TUHH/ Tu Te ch ) , Ge rm a n y a n d t h e Ro ya l In s t it u t e o f Te ch n o lo g y, S t o ckh o lm ,
S we d e n .
No re s p o n s ib ilit y is a cce p t e d fo r t h e a ccu ra cy o f in fo rm a t io n co n t a in e d in t h e re s e a rch p re s e n t e d wit h in t h is Re g is t e r. Th e o p in io n s
e xp re s s e d h e re in a re n o t n e ce s s a rily t h o s e o f t h e Ed it o rs o r t h e p u b lis h e r.
© MCB Un iv e rs it y Pre s s , UK a n d Th o m a s Te ch n o lo g y S o lu t io n s ( UK) Lt d .
[ S e a rch ] [ Ad va n ce d S e a rch ] [ S u b m it Re s e a rch ] [ Ed it Re s e a rch ] [ He lp ]
http://www.mcbup.com/research_registers/emh/sponsors.asp (2 of 2) [04/10/2000 1:05:58 PM]