Reproductive impairment

The reproductive toxicity of some phthalate esters has been reviewed by the Commission of the European Communities (45). This review concludes that testicular atrophy is the most sensitive indicator of reproductive impairment and that the rat is the most sensitive species. 

Nisbet, I.C.T. (1989). Organochlorines reproductive impairment and declines in bald eagle populations mechanisms and dose-response relationships. In B.U. Meyburg and R.D. Chancellor (Eds.) Raptors in the Modern World. Proceedings of the Third World Conference on Birds of Prey and Owls, Berlin 483-489. 

Reproductive impairment seems to be one of the more sensitive indicators of zinc stress in freshwater teleosts, with effects evident in the range 50 to 340 pg Zn/L (Spear 1981). In some cases, reproduction was almost totally inhibited at zinc concentrations that had no effect on survival, growth, or maturation of these same fish (Brungs 1969). Zinc-induced developmental abnormalities were documented in marine teleosts, but concentrations tested were grossly elevated. Eggs of the Baltic herring (Clupea harengus), for example, exposed to >6 mg Zn/L have an altered rate of development and produce deformed larvae with cellular disruptions in the brain, muscle, and epidermis (Somasundaram 1985 Somasundaram et al. 1985). 

Reproductive impairment was reported in several species of waterfowl from a marsh treated with 1.12 kg technical chlordane/ha (Table 13.4). Studies by Lundholm (1988) with two species of ducks (Anas spp.) and the domestic chicken (Gallus sp.) demonstrated that various organochlorine compounds, including chlordane, interfered (in a dose-dependent manner) with reproduction by reducing the binding of progesterone to its cytoplasmic receptor in the shell gland mucosa of birds, especially ducks. 

T. C. Erdman. 1989. Microcontaminants and reproductive impairment of the Forster s tern on Green Bay, Lake Michigan-1983. Arch. Environ. Contam. Toxicol. 18 706-727. 

White, D.H. and J.T. Seginak. 1994. Dioxins and furans linked to reproductive impairment in wood ducks. J. Wildl. Manage. 58 100-106. 

Data are scarce on the toxicity of PCP to mammalian wildlife, but studies with livestock and small laboratory animals show that the chemical is rapidly excreted. However, there is great variability between species in their ability to depurate PCP, as well as in their overall sensitivity. Acute oral LD50 values in laboratory animals were 27 to 300 mg/kg BW. Tissue residues were elevated at dietary levels as low as 0.05 mg/kg feed and at air levels >0.1 mg/m3. Histopathology, reproductive impairment, and retarded growth were evident at doses of 0.2 to 1.25 mg/kg BW, and when the diets fed contained >30 mg PCP/kg. 

PCB diets were associated with reproductive impairment including anovulation, fetal resorption, delayed ovulation, increased gestation, and decreased litter size. Hepatic estrogen binding site concentrations decreased with increasing dietary PCB concentrations but not uterine estrogen receptor sites... 

Reproductive impairment in fish by anthracene (Hall and Oris 1991) and elevated concentrations of total PAHs in sediments (Johnson et al. 1998)... 

Diffusion Experiment Results of the diffusion experiment are shown in Table VI. One or more cm of untreated soil covering 20 g of soil treated with 100 ppm c DDT was very effective in preventing toxic concentrations of DDT from diffusing into water for one year. If any DDT did diffuse through the soil into water, the concentration was not sufficiently high to affect the survival or reproduction of daphnids. A 60% reproductive impairment has been reported when daphnids were exposed to 100 ng/L DDT W. Therefore, on the basis of the daphnid bioassay, the concentration of DDT in water over the 1 cm of soil was at or below 100 ng/L. On the other hand, where untreated soil did not cover the DDT layer, daphnids never survived more than 7 days. This result is very similar to those from the microecosystem experiment. The 1-ml water samples indicated a total DDT concentration of 10 to 20 ppb. In addition, TLC analysis of treated soil extracts after one year showed the expected conversion of DDT to DDD, but only when covered by 1 or more cm of soil. For the uncovered soil, 87% of the radioactivity was DDT. Apparently, 1 cm of soil was sufficient to produce the anaerobic conditions known to be necessary for conversion of DDT to DDD (j 2). 

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