A Toxic Unit and Additive Index Approach to Understanding the Interactions of 2 Piscicides, 3‐Trifluoromethyl‐4‐Nitrophenol and Niclosamide, in Rainbow Trout

The toxic unit and additive index approaches were used to understand how 2 pesticides, 3-trifluoromethyl-4-nitrophenol (TFM) and 2,5-dichloro-4-nitrosalicylanilide (niclosamide; Nic), interact in mixtures. Our first objective was to determine whether the interaction was strictly additive or greater than additive at doses comparable to those used to control invasive sea lamprey (Petromyzon marinus) in the Laurentian Great Lakes, and our second …