Some New Jersey waterways reportedly have "intersex" fish that have raised concerns about estrogen levels in drinking water.

A study from the United States Geological Survey found that two species of male fish caught at Great Swamp National Wildlife Refuge in Morris County and at Wallkill River in Sussex County contained a high incidence of "intersex" aquatic life. The study, published in December, says the fish contain characteristics of both males and females.

The state Department of Environmental Protection called the connection between estrogen in fish and in local drinking water a "stretch," but said it's an issue that the agency has been monitoring. "The bottom line is this is not a new issue, nor does it revolve around one river or wildlife refuge," said Bob Considine, DEP spokesman. "This is about male fish showing female traits have been observed across the globe in all types of waterways."

He said the recent USGS study "adds to our knowledge of this issue and impacts to ecological systems, but the scientific community overall still has more questions than answers on human health impacts." "The DEP will continue to follow and evaluate the science that continues to emerge from across the world," he said. "At the same time, the federal EPA continues to evaluate the science of emerging contaminants of concern and will look toward any guidance the EPA provides.

In 2008, the Associated Press launched a 5-month investigation into pharmaceutical contaminants in drinking water, and discovered drugs in the drinking water of 24 major metropolitan areas, including North Jersey, South California, Philadelphia, San Francisco, Washington D.C. and Arizona.

Traces of drugs included mood-stabilizers, estrogens, metabolized angina medicine and tranquilizers.

The USGS study found intersex in smallmouth bass in 19 locations nationwide. Many of the testing locations were near wastewater treatment plants, industrial sites or agricultural runoff. The Wallkill River site is about three miles downstream from a wastewater treatment plant. Researchers also found evidence that pesticides had previously been stored and used at Great Swamp.