The use of this pesticide has been restricted in the US and banned in the European Union since 2003. 
Flucythrinate has a low water solubility and a high tendency to adsorb to organic matter and suspended particles. It is therefore mostly associated with soils and sediments. In the soil it is moderately stable, with a half-life of 21 days. It has a low tendency towards bioaccumulate.
Flucythrinate is extremely toxic to fish, which start dying at concentrations above 10 ug/l. Marine mammals and sea birds are much more tolerant to the compound, as the are only affected after consumption of several grams per kilogram of body weight. This might be because marine mammals and sea birds seem to be able to excrete flucythrinate more rapidly.
Environmental standards and legislation