Question

9. In a DDT biomagnification study the bioconcentration factors (BCF) for the links in a food chain were determined. Links ВСЕ 800 30 water → Zooplankton ZooplanktonFish A Fish AFish B Fish B → Seagull a. What is the overall biomagnification that occurs from water to seagulls? b. If the water started with 4.7 x 10 mg/mL DDT, what is the concentration in the tissue of Fish B? c. If a seagull had 136 ppm DDT in its tissue, what is the concentration expected in the zooplankton?

Answer 1

answer:

Ans.

bioconcentration factor (BCF) is the ratio of the concentration of the chemical in the organism to its concentration in the ambient environment. i.e.,

BCF = 800 = concentration of DDT in zooplankton / concentration of DDT in water, similarly

30 = concentration of DDT in fish A / concentration of DDT in zooplankton,

2 = concentration of DDT in fish B / concentration of DDT in fish A

5 = concentration of DDT in seagull / concentration of DDT in fish B

Ans a.

overall biomagnification that occurs from water to seagull is = 800*30*2*5 = 240,000

Ans b.

if concentration of water is 4.7 * 10-3 mg/ml DDT then , concentration in the tissue of fish B is,

4.7*10-3 2 30 * 800 = 225.6 mg/ml DDT

Ans c.

if seagull had 136 ppm DDT in its tissue , then concentration expected in the zooplankton is

136 / 5*2*30 = 0.453 ppm

over: