Grand Challenges in Assessing the Adverse Effects of Contaminants of Emerging Concern on Aquatic Food Webs

Much progress has been made in the past decades to understand the sources, transport, fate and biological effects of contaminants of emerging concern (CECs) in aquatic ecosystems. Despite these advancements, significant obstacles remain to comprehensively assess the environmental risks associated with the presence of CECs. Many of these obstacles centre around the extrapolation of effects of single chemicals observed in the laboratory or effects observed in individual organisms or species in the field to impacts of multiple stressors on aquatic food webs. In the current review, the authors identified five challenges that need to be addressed to advance studies of CECs from singular exposure events to multi-species aquatic food web interactions: (i) more detailed information on the complexity of mixtures of CECs in the aquatic environment; (ii) understanding sub-lethal effects of CECs on a wide range of aquatic organisms; (iii) ascertaining the biological consequences of variable duration CEC exposures within and across generations in aquatic species; (iv) linkage of multiple stressors with CEC exposure in aquatic systems; and (v) documenting the trophic consequences of CEC exposure across aquatic food webs. We review the current literature to demonstrate how these challenges can be addressed to fill knowledge gaps.

Authors: Nilsen E, Smalling KL, Ahrens L, Gros M, Miglioranza KSB, Pico Y, Schoenfuss HL. ; Fulll Source: Environmental Toxicology & Chemistry. 2018 Oct 8. doi: 10.1002/etc.4290. [Epub ahead of print]