Several types of fish caught in Delta-area lakes and streams may be contaminated with DDT and toxaphene according to an advisory issued Tuesday by the Mississippi Department of Environmental Quality.
The report recommends citizens not consume bottom-feeding fish more than twice a month if they are caught in Delta lakes and streams. These fish include all carp, buffalo and gar as well as catfish longer than 22 inches.
Phil Bass, director of the MDEQ office of pollution control, also said there is a ban on consumption of buffalo from Roebuck Lake at Itta Bena. He said the amount of toxins found in Roebuck Lake buffalo were slightly higher than other fish in the area.
"DDT is a known carcinogen, and that's why we issued the advisory," Bass said. "What we're concerned about is an increased cancer rate. These are conservative approaches to prevent that."
The advisory only refers to fish caught in the wild, and there is no danger of contamination of the Delta's farm-raised catfish, Bass said.
"It has not affected farm-raised catfish and shouldn't," Bass said. "Both their testing and our testing have shown no danger of these chemicals."
Bass said the farm-raised catfish are not in danger because the commercial ponds are not subject to as much farm run-off, and the catfish are fed a heavy diet that keeps them from regular bottom feeding.
The MDEQ release announced that the Delta was the only region of Mississippi where fish continued to show high levels of DDT and toxaphene.
"The numbers are higher in the Delta because there was more DDT used, and it's a more agricultural land," Bass said. "There tends to be less buffer between farms and water in the area as well."
Bass said DDT was banned in 1972, and toxaphene was banned in the 1980s. He said the chemicals continue to pose a threat because they can remain in soil that is washed into streams and lakes.
Changes in farming practices have decreased the levels of these chemicals in recent years, Bass said. He said he believes conditions are improving in the Delta and will continue to get better.
"We believe that the good news is that you can consume Delta fish if you follow these advisories," he said.
