Additives for the Manufacture and Processing of Polymers

Abstract

Human activity is responsible for the entrance of toxic substances into aquatic ecosystems. These substances entail a risk for the components of the ecosystem (toxicological stress). As a result of global change, aquatic ecosystems are under strong environmental stress due to changes in water flow or nutrient concentration among others. This chapter presents a review of experimental and field studies addressing metal effects on fluvial biofilms and their implications for understanding the potential influence of water scarcity on the fate and effects of metals in fluvial systems. Water scarcity might increase metal exposure (due to low dilution), uptake (due to higher retention under low flow), toxicity and/or accumu- lation (depending on the dose and time of exposure) but may also cause opposite effects depending on the source of pollution. In addition, the influence that water scarcity might have on nutrient loads will also modulate the fate and effects of metals. Future studies addressing the role of environmental stress on the effects of toxicants at a community scale will be fundamental to predict the impact of toxicants in the aquatic ecosystems. Keywords