. Bulletin. Natural history; Natural history. June, 1971 Reintjold et al. : Biodegradability of DDT and Methoxychlor 413 thoxychlor much more than they con- centrated DDT-18 ppm of DDT:38 ppm of methoxychlor after 6 days of ex- posure to the insecticides (Table 4 and Fig. 3). When daphnia and snails were held in water free of insecticide after exposure to DDT or methoxychlor, both organisms excreted radioactive com- pounds. Daphnia excreted methoxy- chlor more rapidly than DDT, while the opposite was true of the snails (Table 4 and Fig. 4). The snails ap- 41 -I parently cannot readily metaboli
. Bulletin. Natural history; Natural history. June, 1971 Reintjold et al. : Biodegradability of DDT and Methoxychlor 413 thoxychlor much more than they con- centrated DDT-18 ppm of DDT:38 ppm of methoxychlor after 6 days of ex- posure to the insecticides (Table 4 and Fig. 3). When daphnia and snails were held in water free of insecticide after exposure to DDT or methoxychlor, both organisms excreted radioactive com- pounds. Daphnia excreted methoxy- chlor more rapidly than DDT, while the opposite was true of the snails (Table 4 and Fig. 4). The snails ap- 41 -I parently cannot readily metabolize methoxychlor and, as a result, retain relatively persistent, high concentra- tions of that insecticide once they have taken it up. This observation agrees with that of Kapoor et al. (1970:1151). The snails, like the other organisms studied, also tend to retain DDT. Uptake and Metabolism by Guppies in a Daphnia-to-Fish Food Chain The results of the daphnia-to-guppy food chain study are shown in Table 5 DDT METHOXYCHLOR â - DAPHNIA â FISH -- SNAILS. .0001 DAYS IN WATER WITHOUT INSECTICIDES Fig. 4. â Loss of radiooctivity from tilapio, snails, and daphnia in water without insecticides following exposure to ppm of DDT or methoxychlor in water. Periods of exposure to insecticides: fish, 12 doys; snails, 6 doys; daphnia, 2 Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Illinois. Natural History Survey Division. Urbana, State of Illinois, Dept. of Registration and Education, Natural History Survey Division
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