Betsy Veach

SLIDELL nn The U.S. Fish and Wildlife Service (USFWS) has approved the emergency use of a pesticide known as naled on Big Branch Marsh National Wildlife Refuge, and the first application will take place before the end of this week, according to St. Tammany Mosquito Abatement Director Chuck Palmisano. Officials with St. Tammany Mosquito Abatement District #2 made requests to use naled on the refuge after rains from Tropical Storm Allison caused mosquito numbers to mount. This approval follows the determination of state epidemiologist Raoult C. Ratard, M.D., that there is a definite high risk of human and animal exposure to Eastern Equine Encephalitis in the parish. "They're allowing us three applications, and the applications must all be ten days apart," said Palmisano. In the meantime, the local appeal to do away with the naled ban on federal property is being reviewed by the USFWS in Washington, D.C. USFWS concerns regarding naled center around the frequency and rate with which the pesticide has been applied in the past. Though naled is licensed by the Environmental Protection Agency (EPA) for use under specific labeling guidelines it has not yet been approved, and further testing is being conducted. EPA guidelines recommend a maximum of six applications per season, of no more than 0.05 pound per acre. St. Tammany Mosquito Abatement District's spraying records indicate that in 2000, 48 applications of naled were made at concentrations of 0.07 pounds per acre. The safety of these higher levels of application have not been examined by the EPA. Naled is a pesticide which interferes with the activities of an enzyme that is essential for proper working of the nervous systems of both humans and insects. Potential harmful effects to wildlife have been documented in a number of studies. These include moderate to high toxicity in ducks and geese, and toxicity to most types of aquatic lifes such as bluegill and the aptly-named mosquito fish, which feeds on mosquito larvae. An additional environmental hazard indicated by EPA for naled is that runoff from treated areas may be hazardous to aquatic organisms in neighboring areas.