Question

Problem 6: (a) Consider the small Kenyan town Obongo, where 29000 people live. They are voracious fish eater, eats 200 gr of fish per day. There average body weight is only 50 Kg and average life span is about 60 years. They do not have waste water or hazardous waste treatment units and dumps all wastes to Kiili river, there source of fish. The concentration of aldrin (pesticide with a BCF of 45000 L/Kg) was found to be 100 PPT (parts per trillion). Determine the incremental risk from fish eating. (10) (b) Give an example of each (1) Synergistic effect (b) Antagonistic effect (c) hormesis (NO Definition) (5)

Answer 1

When you consume fish from contaminated lake or stream with aldrin, an organo chlorine pesticide, you are at high risk of aldrin posioning, when aldrin enters your body it is immediately converted to dieldrin which stays in your body fat for long time, exposure to moderate level of aldrin could cause headache, diziness and uncontrolled muscle movement, but exposure to large amount of these pesticide can cause convulsions, probably death also.

example of synergistic effect . Doctors prescribe combination of ampicillin and gentamycin antibiotic in treating certain bacterial infections because of it's synergesic effect, these antibiotic target the bacterial cell at diffrent levels causing a speedy recovery.

Example of antagonist effect is the opposing action of insulin and glucagon hormones in our body, insulin act by decreasing blood glucose level and glucagon act by increasing the blood glucose level.

Hormesis refers to biphasic dose response, example of hormesis include ischemic preconditioning, exercise, dietry energy restrictions and exposure to low levels of certain phytochemicals