Chlordane concentrations

Chlordane concentrations in held collections of selected animals... 

Table 13.1 Chlordane Concentrations in Selected Nonbiological Samples...

Maximum concentrations of chlordanes in American oysters (Crassostrea virginica) taken in the Gulf of Mexico in 1976 were near 0.1 pg/kg dry weight (Table 13.2). Chlordane concentrations were substantially lower than concentrations of other organochlorines measured in oysters, such as DDT (28 pg/kg) and polychlorinated biphenyls (90 pg/kg), suggesting a need for additional studies on interaction effects of chlordane residues with those of other environmental chemicals (Rosales et al. 1979). 

Marine clams and worms tended to underrepresent chlordane concentrations in the ambient sediments. Concentration factors were less than 0.2 for clams and 0.6 for worms (Ray et al. 1983). Similarly, chlordane concentrations in clams from the Shatt al-Arab River in Iraq closely reflected chlordane concentrations in water particulates when compared to levels in water columns or in sediments (DouAbul et al. 1988). 

Table 13.2 Chlordane Concentrations in Field Collections of Selected Animals (Values shown are in...

Table 13.2 (continued) Chlordane Concentrations in Field Collections of Selected Animals (Values shown are in micrograms per kg [parts per billion] fresh weight [FW], dry weight [DW], or lipid weight [LW].)... 

Residues of dv-chlordanc were preferentially stored and magnified over tran.v-chlordane by freshwater fish and invertebrates in ponds treated with technical chlordane at concentrations up to 1.14 pg/L. The di-isomer, with an estimated Tb 1/2 of 46 days, persisted longer than did the trans-isomer (Johnson and Finley 1980). Tissue concentrations of 106,000 pg total chlordanes/kg, on a lipid weight basis, were associated with reduced survival of estuarine invertebrates (Zitko 1978). Moribund amphipods (Hyallela azteca), for example, contained 137,000 to 2,180,000 pg/kg lipid of various chlordanes, heptachlors, and chlordenes (Zitko 1978). In fish, chlordane concentrations of 300,000 to 4,000,000 pg/kg lipid weight in tissues were lethal (Zitko 1978). 

Resource Criterion or Effective Chlordane Concentration Reference9... 

No studies were found correlating levels to which humans were exposed with actual body burdens. However, an attempt was made to correlate blood levels of chlordane, which may contain from 6% to 30% heptachlor, to duration of occupational exposure. Blood samples from 51 male pest control operators who were occupationally exposed to chlordane were tested for the presence of chlordane and its metabolites trans-nonachlor, oxychlordane, and heptachlor epoxide. The blood of 19 male workers with no experience spraying chlordane was also tested as a control. Heptachlor epoxide was detected (from not detectable to 1.6 ppb) in 20% of the blood samples from pest control operators exposed to chlordane (concentration not reported). The total chlordane in the blood was low but demonstrated sizable correlation with the number of spraying days and the amount of chlordane sprayed (Saito et al. 1986). 

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