Abstract

Freshwater aquatic communities are usually contained within distinct boundaries or systems, and this generates a high degree of connectivity among species, thereby increasing their susceptibility to pesticide-induced disturbances at the community level. Through direct and (or) indirect effects, pesticides can disrupt interactions and linkages among species and impair their ecological function, causing large changes in community stability or balance. The risk of harm posed by pesticides to aquatic communities will depend on the exposure concentration, bioavailability, exposure duration, rate of uptake, inherent species sensitivities, community composition, and other community attributes. Recent advances in pesticide risk assessment for aquatic communities have improved the ecological relevance and predictive capabilities for determining, and thus mitigating, potential harmful impacts. These are explored with some examples of pesticide impacts on aquatic communities, suggestions are provided to minimize the potential for adverse effects of pesticides in aquatic ecosystems, and outstanding issues are identified as a basis for future research.