Publication Abstract

The potential for oestrogenic effects of pesticides in headwater streams in the United Kingdom

M.R. Hurst and D.A. Sheahan

The potential for pesticides to migrate from their point of application into headwater streams is well documented. Pesticides can affect non-target organisms after this translocation by different modes of action. One possible mode of action is disruption of the endocrine system by pesticides mimicking the action of natural oestrogen hormones.

Thirty-nine pesticides were screened for oestrogenic activity using an in vitro recombinant yeast-based assay, along with stormwaters from two different agricultural catchments. Of the 39 pesticides screened for oestrogenic activity, 2 insecticides and 9 fungicides showed an oestrogenic response. These responses ranged in potency from 5000 to 50 million times less potent than 17ß-estradiol (E2), a natural steroidal oestrogen. Equivalent E2 concentrations for the headwater stream stormwater samples ranged from 0.01 to 0.11 ng E2/L. These values are at least two orders of magnitude below levels that have been documented to produce oestrogenic effects in fish and are therefore considered to represent a low risk to headwater stream communities in general. The potential contributions to the oestrogenic activity measured in the headwater streams are discussed.

Reference:

M.R. Hurst and D.A. Sheahan, 2003. The potential for oestrogenic effects of pesticides in headwater streams in the United Kingdom. Science of the Total Environment , 301(1-3): 87-96.