Urine Blood Skin Breath

84  early reversible tissue change e.g. gamma GT gamma-glutamyl transferase  physiological changes e.g.lung function tests  immunological changes e.g.prick tests. Urine and blood are the most common media tested and levels of a toxic substance or its metabolite in urine or blood are measured, giving a yardstick of absorption into the body of a particular substance e.g. finding cadmium in the urine denotes absorption into the body of cadmium, but protein demonstrated in the urine not a normal constituent may indicate kidney damage.

8.1 Urine

Urine can be tested for a wide variety of purposes:  Cells exfoliate cytology - bladder cancer  Level of toxin e.g. mercury  Level of metabolite eg TCA tricarboxylic acid  Protein especially kidney damage  Bile jaundice  Sugar diabetes - relevant to shift work, public service vehicle PSV driving.

8.2 Blood

As with urine, blood can be analysed for a wide range of materials which indicate ill health or the level of a particular substancemetabolite.  Full blood count and haemoglobin - lead, benzene, alcohol, work in the tropics  Serum deep frozen - baseline antibody levels in pathogen exposure  Liver function tests - alcohol, hepatotoxic chemicals  Renal function tests - kidney toxins  Toxin levels - e.g. lead  Metabolite levels - e.g. ALA. 85

8.3 Skin

Appearance - together with knowledge of a substance and history of the individual, especially in the case of irritants. Prick testing - A standardised solution of a substance is introduced just under the surface of the skin on a needle tip. A positive result is an 1mm or larger wheal often with itch and flare within five minutes of the test. This is used to monitor immunological reactions to some respiratory allergens like the enzymes used in biological detergents, or animal dander for those working in animal testing laboratories. The tests are also used to diagnose contact urticaria. Prick testing can safely be used pre-employment when typically the standard series of grass pollen, fur, and house dust allergens are applied.

8.4 Breath

For example, Dichloromethane and carbon monoxide exposure.

8.5 Vision