RALEIGH, N.C., Aug. 27 (UPI) — Fertilizer chemicals that end up in streams and rivers may be causing development abnormalities in aquatic life, U.S. researchers say.
North Carolina State University toxicologists found that nitrates and nitrites — common agricultural fertilizer chemicals — are taken up by water fleas and converted to toxic nitric oxide, a university release said Friday.
Nitric oxide can be toxic to many organisms, and the study found the water fleas were plagued with developmental and reproductive problems consistent with the toxicity, even at what would be considered low concentrations.
This raises questions about the effect the chemicals may have on other organisms, Dr. Gerald LeBlanc, professor of environmental and molecular toxicology at NC State, said.
“There’s only limited evidence to suggest that animals could convert nitrates and nitrites to nitric oxide, although plants can,” he said. “Since animals and plants don’t have the same cellular machinery for this conversion, it appears animals use different machinery for this conversion to occur.”
He said the toxic effects even at low concentrations worried him.
“Nitrite concentrations in water vary across the United States, but commonly fall within 1 to 2 milligrams per liter of water,” he says. “We saw negative effects to water fleas at approximately 0.3 milligrams per liter of water.”
Harmful effects of nitric oxide included developmental delay in which water flea babies were born on schedule but were underdeveloped and, in some cases, lacked appendages important for swimming.
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