Introduction in the mining industry. Despite the lethal concentration (critical) of mercury vapor which is
1. Introduction in the mining industry. Despite the lethal concentration (critical) of mercury vapor which is
Pollution is a great environment problem that has unknown, the exposure to more than (1-2) mg/m 3 of received widespread attention by all countries of the
the initial mercury vapor for few hours causes world for its direct relation to human activity and pulmonary infections. After 2 h of exposure, wounds effectiveness. For several centuries, mercury was used appear in the lung forming a transparent membrane in the pharmaceutical industry as anti-bacteria, and finally pulmonary fibrosis is caused. The clinical antiseptics, skin ointments and laxatives. In the signs of exposure to mercury vapor are different from present time, it has been replaced by other exposure to inorganic mercury salts [1]. pharmaceutical compounds; therefore, they become There is an important characteristic of various less toxic and rare materials as well as they are used in mercury compounds which are different in solubility the chemical and electrical applications. of polar and non-polar solvents. They have different Mercury pollution is one of widespread affinity to the group of (sulf-hydryl) (SH) in the environmental problems. There are two basic sources components of a living cell. These two factors show a of pollution which has high rates of inorganic mercury large degree of toxicity of various compounds.
Corresponding author: Kasim Kadhim Alasedi, Ph.D., Mercury is found in three forms, namely: metallic assistant professor, reasearch field: analytical chemistry. E-mail:
mercury Hg 0 (which is in a liquid form), inorganic [email protected].
The Effect of Mercury on Lipid Peroxidation and its Relation with
Vitamin (A, E) and Essential Elements in Dentals Serum
Hg 1+ , Hg 2+ (which is in a salt form), and organic mercury has been found in kidney and then in the liver, (which is in a form of organic compounds), such as
spleen and brain.
CH 3 Hg. The biological effects vary according to these The average of lethal dose of mercury salts, such as forms and each one of these forms has various toxic
HgCl 2 is 0.2-1 g for an adult. The ability of solubility properties [2].
of other mercury salts is weak, for example The initial symptoms of acute inhalation of metallic
(precipitate, calomel, cinnabar) which is less toxic; the mercury vapor include chilling fever, dyspnea and
lethal dose is 5-10 g. The 100 mg of organic mercury headache after a few hours of exposure. There are
can be fatal for an adult, while the aryl mercury additional symptoms such as: diarrhea, abdominal
compounds are less toxic.
cramps, weak vision and vomiting. In most modern references, the concentration of Severe cases lead to pulmonary edema with
total mercury in the blood (Hg-B) has set a normal breathlessness, cyanosis as well as irritating lungs,
limit which is 3-5 μg/L of total blood which has been severe inflammation of the gastrointestinal tract and
developed (EDTA-blood).
dermatitis (eczema). Other complications include The minimum for this area is less than natural (detection limit) for the routine analytical methods 0-3
subcutaneous emphysema, pneumothorax and death. Acute renal failures happen rarely and symptoms that
μg/L. For more information on occupational, exposures have been routed the biological limits of
occur in the work of the kidney system increase the
exposure to (Hg-B).
excretion of albumin, protein and enzymes in lactation Exposure to inorganic mercury metal 50 μg/L; before the onset of neurological symptoms. Exposure to organic mercury compounds 100 Exposure to high doses more than the permitted
μg/L.
limits will lead to the emergence of neurological The concentration of methyl mercury in the blood is
symptoms, such as symptoms of skin and the about 200 μg/L which may be associated with little possibility of the emergence of symptoms of the
risk of exposure to neurological damage in adults, but digestive system that includes inflammation of the
only little information is available about mercury stomach, diarrhea, and deteriorating health situation of
concentrations in plasma and human serum. the patient such as loss of appetite and emaciation.
Chronic exposure also occurs in the workplace and
2. Materials and Methods
especially in dental clinics.
2.1 Samples
The metallic mercury vapor and mercury salts can This study included 100 doctors, all of them were
be absorbed through the skin, but little is known about male; their services were ranging between one year
the dermal absorption rate for different types of and thirty-four years old. Their ages ranged from
mercury. As an additional route of absorption, the twenty-nine and sixty-three years old. Samples of 40
transition from central oral cavity along the bottom volunteers were collected between the ages of 30 and nerve of tongue and directly to the brain.
50 years old. Samples were divided into groups The metal mercury vapor oxidizes in the blood
according to their period of work, as follows: within a few minutes, but due to the short time of
A = group of doctors (the number of years of work transition from the lungs to the brain, most of the
from 1-15 years old);
mercury vapor uptake in the lungs reaches
B = group of doctors (the number of years of work non-oxidized to the brain. Most of it crosses lipid
from 16-40 years old);
barrier. Naturally, the highest concentration of
C = control group.
The Effect of Mercury on Lipid Peroxidation and its Relation with
Vitamin (A, E) and Essential Elements in Dentals Serum
2.2 Methods of Work solution were prepared by using the mobile phase 99% methanol, 1% distilled water in a wavelength 287
2.2.1 The Measuring of the Level of Mercury in the nm, column type (ODS) C-18. Vitamin A also uses Blood Serum the mobile phase 99% methanol, 1% distilled water in The nature of the mercury concentrations found in
a wavelength 330 nm in the same column. animal tissues is not less than 0.01 ppm; therefore, the
2.2.4 Measurement of Albumin in Serum method of mercury analysis must be precise enough to This method depends on the measure of the amount allow analysis of a small percentage of ng/g based on of albumin in the blood serum on the link to the familiar experience. quantitative reagent 3, 3, 5, 5-Tetrabromo-metacresol Cold Atomization Method is used in quantity sulfophthaline (BCG) because albumin forms a determination of organic and inorganic mercury which complex with the (BCG) and gives the absorbance on is the most accurate, precise and easy compared with
a wavelength 630 nm according to ready-made kit of other methods used to determine the mercury. The
(Randox) company.
detection limit is up to 0.2 ng in which the mercury is
The absorbance of the sample, the standard solution oxidized to the Hg . Then, it is treated with a
and the solution are taken blank in the wavelength 630 reducing agent such as acid solution binary tin. After
nm using the cell absorption in a width 1 cm. The that the atomized mercury is released, evaporated
concentration of albumin in the sample is calculated from the solution, and passed into an absorbance cell.
by applying the following equation: The mercury amount is measured as a result of
Albumin concentration (g/100mL) = Sample passing the radiation beam resonance.
absorption/Concentration of standard solution × The sensitivity of this method depends on the
Absorption standard solution
device used, sample size and concentration of mercury
2.2.5 Measurement of Hemoglobin (Hb) which helps on the success of cold atomization and its
The amount of hemoglobin is measured by vapor is not oxidized in the air. The method used is
sodium borohydride reduction. This method cannot cyanomethohemoglobin by depending on the distinguish between various forms of mercury in the
published research in (WHO 1990) in a laboratory sample. The mercury is measured as a whole and its
methods brochure depended in blood diseases in Iraqi sample is diluted by adding water and sodium
health laboratories.
borohydride with wavelength 253.7 nm. Absorbance is read using a spectrophotometer with
a wavelength 540 nm and used drapkin solution as Blood serum by MDA
2.2.2 Determination of the Level of Oxidation in
blank. The value of hemoglobin is set in units of The malondialdehyde is a product of lipid per
grams per 100 mL according to the following law. oxidation. The measurement of this substance gives
Absorbance of dissolved blood
the impression of the level of oxidation. The color Hemoglobin concentration (g/100 mL) = method is used that depends on the interaction
concentration of standard solution × dilution factor × between the thiobar butyric acid and absorbance of analyzed blood/absorbance of the malondialdehyde to give a color compound that
solution standard
absorbs in 532 nm [3].
2.2.6 Electrophoresis of Proteins by Using
2.2.3 Measurement of Vitamin (A, E) in Blood
Cellulose Acetate Paper
Serum by HPLC The method of migration electricity using paper of Vitamin E is measured by using the modified way
cellulose acetate by using clinical chemistry methods of Deleen heer. The antioxidant solution and standard
to set the protein spots which are found in blood
The Effect of Mercury on Lipid Peroxidation and its Relation with
Vitamin (A, E) and Essential Elements in Dentals Serum
serum. The process should put a drop of sample on the flameless atomic absorption spectroscopy, and put 10 sheet of cellulose acetate paper in an electric field
μL for each standard solution. While the Zn, Mg are with a specific voltage to get deportation of proteins
measured by flame atomic absorption with putting 0.8 with various velocities depending on the molecular
mL for each standard solution. Blood samples are weight and protein charge [4, 5].
measured by using a special funnel with a sample syringe 0.25 mL. In the flameless atomic absorption,
2.3 Solutions and Materials
10 μL of sample is taken. All measurements are used (a) Buffer solution: Consists of 12.76 g of sodium
by using wavelengths of the above elements. barbiton.
Sodium barbiton with 1.66 g of diethyl barbituric
3. Results and Discussion
acid in the volume of distilled water and Table 2 shows the increase in the rate of lipid per complementary to 1 L and adjust the mixture of pH
oxidation to the totals of doctors compared to control
8.6. group where the authors note the increase with the (b) Dye solution: Dissolve 1 g of ponceaus with 3 g
time period of exposure. The researchers were able to of TCA acid and complements the volume to 100 mL
interpret the increase of lipid per oxidation mechanism with distilled water.
due to high levels of (ROS) are generators of free (c) Washing solution: The solution consists of one
radicals. An increase in damage to the cells will volume of acetic acid 5% and 9 volumes of methanol
happen and it will accelerate the transition of electrons and the one volume of glacial acetic acid.
and lipid per oxidation in biological tissues in a living
2.4 Procedure cell. These results agree with other researches and when the increase of lipid per oxidation the free
(1) The buffer solution is added a separation pool radicals that are generated and the grown lead to the
and cellulose acetate paper is filled in the tank, and damage of many cellular membranes and nerve then it is taken out and dried;
endings in the brain [6].
(2) Put the sample on cellulose acetate paper by capillary tube at a distance 1 cm of paper edge, and
Table 1 Determines the standard deviation and the mercury average level of significance in the control group
place the paper in the separation pool and fix the
and doctors’ groups.
voltages at 150 V and DC for 40 min; ± SD average Hg
No. Groups (3) Put the paper in the dye pool which contains the
Mean
( g/dL)
40 Ponceau S. dye for 10 min, and then it is placed in the C
50 A washing solution;
P 0.001 0.948
50 B (4) Compare the spots that appear with proteins
P 0.001 2.890
A = group of doctors (from one year to 15 years); spots in normal serum.
B = group of doctors (from 16 years old and above); C = control group.
2.5 Atomic Absorption Method for Determination of
Table 2 The rate of standard deviation and level of
Trace and Essential Elements in Serum
significance (MDA) in the control group and doctors groups.
Mean ± SD Av. (MDA) (n mol/dL) No. Groups Mg, Zn and Se for the purpose of drawing a standard
Standards solutions are prepared of the elements
15.50 5.6 40 C curve for each of the above elements through taking
---
P 0.050 29.80 3.1 50 A P 0.001 40.27 7.8 50 B
different amounts of each element in volumetric flask A = group of doctors (from one year to 15 years); with deionized water. Different standard solutions are
B = group of doctors (from 16 years old and above); measured by using atomic absorption, for Se use
C = control group.
The Effect of Mercury on Lipid Peroxidation and its Relation with
Vitamin (A, E) and Essential Elements in Dentals Serum
Table 3 shows a decrease in the level of The level of hemoglobin in the blood serum Table 5 concentration of vitamin A for doctors compared with
shows that the proportion of hemoglobin was in the control values with the length of exposure.
level of the natural limits. Since the hemoglobin has The vitamin A of the carotenoids compounds has
proved its importance in stimulating the lipid per effective of anti-oxidation. The chemical activity
oxidation, its levels raised with hemoglobin increase comes from a long chain containing conjugated
and there is no indication in the studies and researches double bonds which is exposed to various groups of
on infecting workers with anemic or non-infected
when they are exposed to mercury. peroxy radical.
ROS that vitamin A can gain, which are O 2 and
Table 5 shows the lack in the level of albumin in
Vitamin A has many functions including groups of workers compared with a control group participating in the process of vision to interact with
because the albumin is one of antioxidant that works the opsin protein forming visual purple which is also
by connecting the copper and iron with radicals. The necessary in the formation of mucous carbohydrates
lack of albumin leads to a few in the clearance of free which constitute mucosa material to secrete layer
radicals, and therefore, increases the lipid per epithelium that provides protection for channels of
oxidation.
the body, such as respiratory, urinary and The low level of albumin in the blood serum leads reproductive, as well as conjunctivitis and corneal
to many disorders, the most important ones are and gums [7].
pressure and blood viscosity because the albumin The vitamin has a great role in the formation of a
form about 60% of the proportion of total protein number of hormones such as topical steroids in the blood. Thus, the decline in the level of albumin
(cortisone), which is produced by the adrenal gland
Table 3 The rate of standard deviation and level of
that plays a role in the processing of fat and
significance of the concentration of vitamin A in the control
carbohydrates.
group and doctors groups.
SD Av. (Vit-A) (mg/dL)
No. Groups importance in the conservation on the eye and ocular
It also recommended to eat vitamin A because of its
Mean
69.8 10.2 40 C conjunctiva and cornea of the eye from damage as
---
P 0.050 44.6 14.1 50 A P 0.001 35.5 16.5 50 well as vitamin A role in raising the level of apo-A B
and then raise (HDLC) in the blood [8].
Table 4 The rate of standard deviation and level of
Table 4 shows the lack in the rate of vitamin E in
significance of the concentration of vitamin E in the control group and doctors groups.
the totals of doctors compared with a control group because (Vit-E) is a soluble antioxidant in fat and works
Mean SD Av. (Vit-E) No. Groups
(mg/dL)
to protect the fats in cell membranes from oxidation
1.240 0.16 40 C damage. The vitamin E affects the cellular immune
---
P 0.050 0.872 0.21 50 A response, where it works to strengthen the immune
P 0.001 0.751 0.38 50 B
status. The few (Vit-E) as a result of its damage and
Table 5 The rate of standard deviation and level of
reduce the immune response to the workers. The
significance of the hemoglobin in the control group and
effect of vitamin E is to stimulate cells T. Helper workers groups. ± SD Conc. Av. Hb
Lymphocytes, which works to transform the
No. Groups production of antibodies IgM type to IgG type. The
Mean
(g/dL)
40 C present results in this research are consistent with
---
50 A what came in the results of many researchers [9, 10].
P 0.050 15.15 0.340
P 0.001 14.79 0.420
50 B
The Effect of Mercury on Lipid Peroxidation and its Relation with
Vitamin (A, E) and Essential Elements in Dentals Serum
leads to disturbances in important functions of the Table 8 shows a reduction in the level of selenium body.
with increasing duration of exposure of mercury and The significance level of magnesium: Table 7
explains their role in increasing of consumption of shows that the rate of the magnesium level increases
selenium, which plays an important role and as a basis in the group of workers compared with the control
in the work of the glutathione peroxide enzyme. This group and there was a positive correlation between the
enzyme is antioxidants and found in most members of level of the enzyme SOD and the magnesium element
the body [12].
in the blood serum of workers. The presence of Table 9 shows a reduction in the level of zinc with magnesium in the fluid inside the cell is in more
increasing duration of exposure to mercury. The zinc concentrations than in extra cellular fluid and this can
element is very important in humans as it is an
be attributed to the increase in the concentrations essential element for more than 100 metal enzyme, outside the cell, and then leads to the damage of the
such as alcohol dehydrogenase and DNA and the cells; thus, increase the percentage in the blood
polymerization of DNA.
serum [11]. The Zinc is an essential element in the growth and
Table 6 Determines the standard deviation and level of
cell division and it is also considered as an essential
significance albumin when the control group and workers
element in the process of metabolism of collagen [13].
groups.