| Autor: |
Raimondo, Sandy1 raimondo.sandy@epa.gov, Hemmer, Becky L.1, Goodman, Larry R.1, Cripe, Geraldine M.1 |
| Předmět: |
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| Zdroj: |
Environmental Toxicology & Chemistry. Nov2009, Vol. 28 Issue 11, p2409-2415. 7p. 1 Diagram, 3 Charts, 3 Graphs. |
| Abstrakt: |
The evaluation of multigeneration, population-level impacts is particularly important in the risk assessment of endocrinedisrupting compounds, because adverse effects may not be evident during the first generation of exposure. Population models were developed for the sheepshead minnow (Cyprinodon variegatus) exposed to 17b-estradiol (E2) for two complete generations (F1 and F2) to determine population-level effects of multigenerational exposure to a model estrogen. Stage-structured matrix models were used to determine interactions between treatment and the number of generations exposed. Reproduction was significantly reduced in both the 0.08 and 0.2 μg E2/L treatments in both generations, and embryo and larval stages experienced reduced survival at 0.2 μg/L in the second generation only. However, increased female to male sex ratio in these treatments compensated for the loss in reproductive output, and significant population-level effects only occurred in the 0.2 μg E2/L treatment of the F2 population. The F2 population in the 0.2 μg E2/L treatment also had an altered, stable stage distribution relative to the control population of both generations and the F1 population in the 0.2 μg E2/L treatment, resulting in additional population-level effects. These results demonstrate that continued exposure to E2 had compounding effects on sheepshead minnow populations and that long-term exposures may be necessary to understand the risk that exposures to environmental estrogens pose to native populations. Although population-level effects did not occur in the F1 generation, a risk decision based on F1 organism-level effects would be protective of the population exposed for two generations. [ABSTRACT FROM AUTHOR] |
| Databáze: |
GreenFILE |
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