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Uptake of 14C DDT by wood frog embryos after short term exposure
Abstract:
Wood frog embryos at four different developmental stages and three temperatures were subjected to 0.025 ppm 14C DDT for 24 hr. Embryos within jelly capsules at stages 13, 16 and 18 accumulated about 0.16 ppm at 9, 15 and 21 degrees C. The protective jelly envelopes around embryos in stages 13, 16 and 18 contained about 0.014 ppm at all temperatures. Jelly-free hatching embryos in stage 20 accumulated about 6-10 times the level of earlier stages and showed effects of DDT poisoning. Jelly capsules around amphibian eggs restrict DDT uptake.
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