Ecotoxicology is the study of the harmful effects of toxic substances on ecosystems and the organisms within them. It combines principles from ecology and toxicology to understand how pollutants impact environmental health, including the effects on species, populations, communities, and entire ecosystems. Researchers in ecotoxicology assess the fate and transport of contaminants, their exposure pathways, and the resultant ecological impacts, aiming to inform risk assessment, regulatory policies, and environmental management practices.