Reproductive capacity

A major difficulty which has been encountered with these definitions (identified as a particular problem by EDSTAC) is the definition of the term adverse . For a chemical to be judged an ED, it is important to show that the response seen has an adverse effect on the health or reproductive capacity of affected organisms or populations and is not just a change which falls within the normal range of physiological variation. 

Few studies have been conducted on other invertebrate taxa but pentach-lorophenol exposure has been shown to affect daphnid reproductive capacity and sex steroid hormone metabolism and a high incidence of intersex has been observed in harpacticoid copepods near an Edinburgh sewage outfall. " ... 

Stilboestrol Reproductive organs Improved reproductive capacity... 

Biological limits are also in force for lead and its compounds under the Control of Lead at Work Regulations 1998 different blood lead action, and suspension from work, levels apply to women of reproductive capacity, young persons and other employees. 

Salisbury, E.J. (1942). The Reproductive Capacity of Plants. London Bell. 

Bertsche U. 1978. The response of diploid yeast to radiations at different LET I. Potentially lethal and lethal damage to reproductive capacity. Radiat Res 76 349-367. 

This technology is most often applied to valuable animals (e.g. prize winning horses, or high milk-yield dairy cattle) in order to boost their effective reproductive capacity several-fold. All the offspring will inherit its genetic complement from the biological mother (and father), irrespective of what recipient animal carries it to term. 

Populations of freshwater oligochaetes and leeches were reduced in numbers of individuals and numbers of taxa in mine tailing effluents containing 146 to 213 pg Zn/L or sediments containing >20 g Zn/kg DW (Willis 1985b). Leeches (Erpobdella octoculata) experienced a reduction in density and reproductive capacity in streams containing 25 to 310 pg Zn/L from mine wastes and did not avoid these harmful concentrations (Willis 1989). 

AQUATIC INSECTS No effect on survival, behavior, or asexual reproductive capacity after 24-h exposure 23... 

Kettering Laboratory. 1971. The reproductive capacity among dogs fed diets containing endrin. Prepared by The Kettering Laboratory in the Dept, of Environmental Health, College of Medicine, Univ. of Cincinnati for Velsicol Chemical Corp. 

Meyer CR. 1984. Critical review of studies relating occupational exposures of males and reproductive capacity. In Lockey JE, Lemasters GK, Keye WR Jr, eds. Reproduction The new frontier in occupational and environmental health research. New York, NY Alan R. Liss, Inc., 375-384. 

In a dominant lethal assay, eight male Charles River CD-I mice received single oral doses of 7.5 or 15 mg/kg of a heptachlor heptachlor epoxide mixture (25% 75%) and were bred with three untreated females each week for 6 weeks (Arnold et al. 1977). No adverse effect on the reproductive capacity of male mice was noted therefore, the NOAEL was 15 mg/kg. A LOAEL was not established. Both heptachlor and heptachlor epoxide were also tested separately in another dominant lethal assay in mice. Heptachlor was tested at 5 and 10 mg/kg and heptachlor epoxide at 8 mg/kg/day. Neither agent produced early fetal deaths or preimplantation losses outside the control limits (Epstein et al. 1972). 

Developmental toxicity and impaired reproductive capacity were seen in two oral studies in mice. " The lowest observed adverse effect level was lOmg/l /day from day 7 to day 16 of gestation."... 

In two three-generation studies with rats administered heptachlor, heptachlor epoxide, or a mixture of the two in the diet, the number of resorbed fetuses increased and the fertility decreased with succeeding generations. No adverse effects on reproductive capacity were reported in male mice receiving single oral doses of 7.5 or 15mg/kg heptachlor heptachlor epoxide (25% 75%) in a dominant lethal assay. Heptachlor epoxide has been found in tissues of stillborn infants, indicating transplacental transfer. ... 

However, the primary intent of physiological systems is not to increase individual size but to produce a functioning organism that can reproduce itself The reproductive capacity of living systems involves another complicated set of chemical reactors that we will not consider here. However, we will examine the kinetics of populations of living systems in Chapter 8 in connection with environmental modeling. 

CS170 Kostellow, A. B., D. Ziegler, J. Kunar, G. I. Fujimoto and G. A. Morrill. Effect of cannabinoids on estrous cycle, ovulation, and reproduction capacity of female A/J mice. Pharmacology 1980 21 68-75. 

Wilson J.G. and H.C. Wilson (1943). Reproductive capacity in adult rats treated prepuhertally with androgenic hormone. Endocrinology 33 350-353. 

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