Gaikowski, M.P., U.S. Geological Survey (USGS), Upper Midwest Environmental Sciences Center (UMESC), La Crosse, 
Wisconsin, U.S.A 54603 mark_gaikowski@usgs.gov
Schmidt, L.J., USGS, UMESC, La Crosse, Wisconsin, U.S.A 54603 larry_schmidt@usgs.gov
Stehly, G.R., USGS, UMESC, La Crosse, Wisconsin, U.S.A 54603 guy_stehly@usgs.gov
Larson, W.J., USGS, UMESC, La Crosse, Wisconsin, U.S.A 54603 wendi_larson@usgs.gov
Gingerich., W.H., USGS, UMESC, La Crosse, Wisconsin, U.S.A 54603 william_gingerich@usgs.gov

AN EVALUATION OF POTENTIAL ENVIRONMENTAL FATE AND EFFECTS OF CHLORAMINE-T USE IN U.S. 
INTENSIVE AQUACULTURE.

U.S. Food and Drug Administration (FDA) approval is currently being sought for the use of chloramine-T as a waterborne 
therapeutant in aquaculture to control mortality associated with bacterial gill disease in cultured freshwater fish. We reviewed 
and characterized potential impacts, and environmental fate and effects of chloramine-T discharge into freshwater ecosystems 
after aquaculture use. The review represents only a portion of the FDA requirements to assess environmental safety. Our risk 
characterization integrates 1) available fate and effects data, 2) a recent USGS survey that detailed the projected use and 
discharge patterns of chloramine-T at U.S. aquaculture facilities, and 3) chloramine-T effluent monitoring following typical 
production raceway treatments. We modeled potential environmental effects of chloramine-T based on estimated 
environmental introduction concentrations (EIC) because of the lack of available degradation data and because chloramine-T 
may be regarded as total residual chlorine (TRC). Available data suggest that chloramine-T is much less toxic than TRC.

SS 1-01 CS02
POSTER
GAIKOWSKI, M.P.