The most probable routes of human exposure to endothall are inhalation and dermal contact of workers involved in the manufacture, handling or application of endothall. The general public could potentially be exposed through use for lawn weed control. If released to soil, endothall is expected to rapidly biodegrade under aerobic conditions. The half-life of endothall is reported to be 4 to 5 days in clay soils and 9 days in soils with high organic content . Chemical hydrolysis and volatilization are not expected to be significant fate processes.
Glutamic acid is a major biotransformation product of endothall under aerobic conditions.
Endothall is not expected to oxidize, chemically hydrolyze, photolyze, volatilize, bioaccumulate or adsorb to suspended solids or sediments. In experimental greenhouse pools treated with 0.03, 1.6 or 4.5 ppm endothall, an overall half-life of 4 days was reported . If released to the atmosphere, endothall is expected to exist predominantly on particles and should either settle out or wash out in precipitation. Endothall is not expected to chemically react or photolyze in the atmosphere. There were no measurable changes in water quality after treatment and macrophyte die off with the exception of a general decrease in dissolved oxygen.