Reported by Aly Thomson in The Regina Leader-Post, the study, being published in Philosophical Transactions of the Royal Society, found that introducing small amounts of estrogen into a lake led to the near extinction of the fathead minnow because it interfered with the fish’s ability to reproduce.
Lead researcher Karen Kidd of the University of New Brunswick said the study has been ongoing since the late 1990s, when researchers in the United Kingdom discovered that male fish began to develop eggs when estrogen from birth control pills was introduced in their habitat.
The Canadian Press story noted that, “Kidd said their study set out to build on that research to determine whether the estrogen would affect the fathead minnow’s ability to reproduce and whether there were larger effects on the lake’s ecosystem.
“Researchers started introducing small amounts of estrogen into an Ontario freshwater lake research facility in 2001, Kidd said. “Right away, the male fish started to respond to the estrogen exposure by producing egg yolk proteins and shortly after that they started to develop eggs,” she said in Saint John, N.B. “They were being feminized.”
“It’s evidence that removing these chemicals from our effluents will have downstream benefits for the fish population,” she said.