Developmental/reproductive effects

Among the most sensitive endpoints (on a body burden basis) are endometriosis, developmental neurobehavioural (cognitive) effects, hearing loss, developmental reproductive effects (sperm counts, female urinogenital malformations) and immuno-toxic effects, both adult and developmental. The most sensitive biochemical effects are CYP1A1/2 induction, hepatic retionid depletion, EGF-receptor down-regulation and oxidative stress. 

TCDD and structurally related compounds elicit a wide range of adverse effects. Of the many adverse responses observed both in humans and experimental animals after exposure to 2,3,7,8-TCDD, the ones that appear at the lowest dose (more sensitive) are perhaps developmental/reproductive effects, alterations in the immune response, and neoplasia. An overview of the mechanism(s) involved in these effects is presented below. Detailed mechanistic explanations are beyond the scope of this profile. Some of the information has been extracted from recent reviews on these subjects (Kerkvliet 1995 Lucier et al. 1993a Peterson et al. 1993). 

The lowest observed effect levels for pentaBDE congeners in animal toxicity studies are for developmental neurotoxicity, decreased thyroid hormone (endocrine disruption) and developmental reproductive effects (WA 2006, p.23). 

Chemical Regulation Reporter, Final NMP Review Finds Significant Risk of Developmental, Reproductive Effects, Bureau of National Affairs, Inc., Washington, DC, pp. 1119-1121 (September 24, 1993)... 

Another section of the EPA, the Office of Prevention, Pesticides, and Toxic Substances (OPPT), has recently updated and harmonized its testing guidelines for evaluating the developmental and reproductive effects of pesticides and industrial chemicals to include an assessment of endocrine disrupting properties. These guidelines will be used in future testing of pesticides under both the Toxic Substances Control Act (TSCA) and the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA). 

Health Effect The major categories of health effects included in LSE tables and figures are death, systemic, immunological, neurological, developmental, reproductive, and cancer. NOAEEs and EOAELs can be reported in the tables and figures for all effects but cancer. Systemic effects are further defined in the "System" column of the LSE table (see key number 18). 

To help public health professionals address the needs of persons living or working near hazardous waste sites, the information in this section is organized first by route of exposure—inhalation, oral, and dermal—and then by health effect—death, systemic, immunological, neurological, developmental, reproductive, genotoxic, and carcinogenic effects. These data are discussed in terms of three exposure periods—acute (14 days or less), intermediate (15-364 days), and chronic (365 days or more). 

A substance can cause one or more effects. Common effects are acute and longterm toxicity, skin irritation, corrosiveness, sensitization, mutagenicity, carcinogenicity, reproductive effects, and developmental toxicity. 

Health Effect The major categories of health effects included in LSE tables and figures are death, systemic, immunological, neurological, developmental, reproductive, and cancer. 

No studies addressing developmental or reproductive effects following acute inhalation exposure to aniline were located. However, because effects on development and reproduction arise after systemic uptake, oral administration of aniline can be considered for evaluating potential developmental and reproductive toxicity. Aniline (administered as aniline hydrochloride) readily crosses the placental barrier in rodents (Price et al. 1985). 

The only available data regarding developmental and reproductive effects of dimethylhydrazine involved parenteral administration and, therefore, are of questionable relevance for AEGL derivation. The data are included, however, to provide insight relative to dimethylhydrazine exposure. 

No data concerning developmental or reproductive effects of HCN in humans were identified in the available literature. 

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