Bioconcentration Calculations

In Chapter 2 and 3, we discussed bioconcentration and looked at DDT data from a food chain on Long Island, NY (Table 2.3). The data from Table 2.3 are reproduced in Table 10.10, where we used it to calculate bioconcentration factors (BCFs) for each animal species. Each BCF is calculated by dividing the DDT concentration in each animal by the water concentration. As you can clearly see, DDT is increasingly bioconcentrated as we move up the food chain, from 800 in the first tropic level to 528,000 in birds that eat fish.

Bioconcentration factors, given in Table 10.11, can be used to estimate cancer risk for a person eating contaminated fish, as is illustrated in the following problem.

Example Problem. EPA estimates that an average person might eat 54 g of fish per day. Calculate the cancer risk of a 70.0-kg person who eats 54g of fish per day, 350

TABLE 10.10. Bioconcentration Factor for DDT in a Long Island Food Web (United States)

Organism DDT Residues (ppm) BFC (L/kg)

TABLE 10.10. Bioconcentration Factor for DDT in a Long Island Food Web (United States)

Organism DDT Residues (ppm) BFC (L/kg)

Water

0.00005

Plankton

0.04

800

Silverside minnows

0.23

4,600

Sheephead minnows

0.94

19,200

Pickerel (predatory)

1.33

26,600

Needlefish (predatory)

2.07

41,400

Heron (feeds on small aquatic animals)

3.57

71,400

Herring gull (scavenger)

6.00

120,000

Osprey egg

13.8

276,000

Merganser (fish-eating duck)

22.8

456,000

Cormorant (feeds on large fish)

26.4

528,000

TABLE 10.11. Bioconcentration Factors (BFCs) for Selected Pollutants (U.S. EPA, 1986)

BCF for

BCF for

Compound

Fish (L/kg)

Compound

Fish (L/kg)

Acenaphthene

242

Fluorine

1,300

Acrylonitirle

48

Heptachlor

15,700

Aldrin

28

Heptachlor epoxide

14,400

Antimony

1

Hexachlorobenzene

8,690

Arsenic

44

Hexachlorobutadiene

2.8

Benzene

5.2

Hexachlorocyclopentadiene

4.3

Benzidine

87.5

a-Hexachlorocyclohexane

130

Beryllium

19

(HCCH)

Bis(2-chloroethyl)ether

6.9

ß-HCCH

130

Bis(chloroethyl)ether

0.63

g-HCCH (Lindane)

130

Cadmium

81

Hexachloroethane

87

Carbon tetrachloride

19

Kepone

8,400

Chlordane

14,000

Lead

49

Chlorobenzene

10

Mercury (alkyl)

3,750

Chloroform

3.75

Mercury (inorganic)

5,500

Chromium III

16

Methyl parathion

45

Chromium VI

16

Nickel

47

Copper

200

Pentachlorobenzene

2,125

DDE

51,000

Pentachlorophenol

770

DDT

54,000

Phenanthrene

2,630

1,2-Dichlorobenzene

56

Phenol

1.4

1,3-Dichlorobenzene

56

Polychlorinated biphenyls

100,000

1,4-Dichlorobenzene

56

(PCBs)

3,3'-Dichlorobenzidine

312

Selenium

16

1,2-Dichloroethane

1.2

Silver

3,080

1,1-Dichloroethylene

5.6

1,2,4,5-Tetrachlorobenzene

1,125

1,2-Dichloroethylene

1.6

2,3,7,8-TCDD (Dioxin)

5,000

1,2-Dichloroethylene (cis)

1.6

1,1,2,2-Tetrachlorothethane

42

1,2-Dichloroethylene (trans)

1.6

Tetrachloroethylene

31

Dichloromethane

5

2,3,5,6-Tetrachlorophenol

240

2,4-Dichlorophenol

41

Toluene

10.7

1,3-Dichloropropene

1.9

Toxaphene

13,100

Dieldrin

4,760

1,2,4-Trichlorobenzene

2,800

Diethyl phalate

117

1,1,1-Trichloroethane

5.6

2,3-Dinitrotoluene

3.8

1,1,2-Trichloroethane

5

2,4-Dinitrotoluene

3.8

Trichloroethylene

10.6

2,5-Dinitrotoluene

3.8

2,4,5-Trichlorophenol

110

2,6-Dinitrotoluene

3.8

2,4,6-Trichlorophenol

150

3,4-Dinitrotoluene

3.8

tris(2,3-Dibromopropyl)

2.7

A^N-Diphenylamine

30

phosphate

1,2-Diphenylhydrazine

25

Vinyl chloride

1.17

Ethylbenzene

37.5

Zinc

47

Fluoranthene

1,150

Exhibit A-1 in Superfund Public Health Evaluation Manual, Office of Emergency and Remedial Response, Washington, DC).

Exhibit A-1 in Superfund Public Health Evaluation Manual, Office of Emergency and Remedial Response, Washington, DC).

days each year for 30 years. Assume that the water the fish was taken from has a Chlordane concentration of 0.0100ppb (|mg/L). The oral slope factor for Chlordane is 3.5 x 10-1.

First we must calculate the concentration in the fish. Chlordane concentration in fish = pollutant concentration in fish x BCF

= 0.0000100 mg/L x 14,000 L/kg = 0.14 mg Chlordane/kg fish

Using Eq. (10.7), we can then calculate the CDI:

BW x AT

= 0.14 mg/kg x 0.054 kg/day x 1.00 x 350 days/year x 30 years

70 kg x 30 years x 365 days/year = 1.04 x 10-4 mg/kg • day (10.7)

Risk = CDI x Slope factor = 1.04 x 10-4 mg/kg • day x 3.5 x 10-1 (mg/kg • day)-1 = 3.62 x 10-5 or 36 cancer cases per million people eating the fish

Thus, 36 cancer cases should develop among one million people consuming the contaminated fish.

Continue reading here: Putting It All Together Margin Of Error Uncertainty Of The Entire Estimation Process

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  • kalimac
    How to monitor bioconcentration factor?
    3 months ago
  • pekka
    How to determine bioconcentration?
    2 years ago
  • andrea
    How to calculate bioconcentration factor?
    2 years ago
  • jens
    How to calculate ingestestion from bioconcentration factors?
    3 years ago
  • Ralf Nagel
    Does ddt has a fish concertration of 54000 l/kg?
    5 years ago