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Research on Detecting Endocrine Disrupting Chemicals from Animal Feeding Operations

Waste from animal agricultural feeding operations contain nutrients such as nitrogen and phosphorus, but also endocrine disrupting compounds (EDCs) - mainly estrogens, testosterone and other hormones released directly from the animals. The ability to contain waste and prevent it from leaking into surrounding surface water and groundwater is variable due to factors such as the material used to line the lagoon that contains animal feeding operation waste.

EPA assesses animal feeding operations to determine how much they contribute to endocrine disrupting chemicals that can be found in the lagoons and nearby groundwater and waterways.  EPA scientists are developing methods to accurately measure endocrine disrupting chemicals found waste from concentrated animal feeding operations.

concentrated animal feed operation
EPA scientists are developing methods to accurately measure endocrine disrupting chemicals in concentrated animal feeding operations

Research suggests that hormones released by animal feeding operations may affect fish communities by reducing diversity and skewing the sex ratio towards the production of males. One study examined groundwater near seven animal feeding operations, housing pigs, beef cattle, dairy cows, or poultry. The researchers detected estrogens in groundwater associated with piping from animal feeding operations that leaked directly into aquifers and were known to be discharging into groundwater.

Preliminary findings suggest that land application of animal feeding operation waste may not contribute substantially to estrogen in groundwater because certain soil conditions may foster the biochemical breakdown of these hormones. EPA research helps develop management strategies to protect groundwater from endocrine disrupting chemicals in animal feeding operation waste. Preliminary data suggest the possibility that proper management of contamination may reduce concentrations of other environmental stressors such as estrogen hormones to acceptable risk levels.