Toward a Conceptual Approach for Assessing Risks fromrnChemical Mixtures and Other Stressors to CoastalrnEcosystem Services

摘要

Growth of human populations and increased human activity, particularly in coastal areas, increase pressure on coastalrnecosystems and the ecosystem services (ES) they provide. As a means toward being able to assess the impact of multiplernstressors on ES, in the present study we propose an 8-step conceptual approach for assessing effects of chemical mixtures andrnother stressors on ES in coastal areas: step A, identify the relevant problems and policy aims; step B, identify temporal andrnspatial boundaries; step C, identify relevant ES; step D, identify relevant stressors (e.g., chemicals); step E, translate impactsrninto ES units; step F, assess cumulative risk in ES units; step G, rank stressors based on their contribution to adverse effects onrnES; and step H, implement regulation and management as appropriate and necessary. Two illustrative case studies (Swedishrncoastal waters and a coastal lagoon in Costa Rica) are provided; one focuses on chemicals that affect human food supply andrnthe other addresses pesticide runoff and trade-offs among ES. The 2 cases are used to highlight challenges of such riskrnassessments, including use of standardized versus ES-relevant test species, data completeness, and trade-offs among ES.rnLessons learned from the 2 case studies are discussed in relation to environmental risk assessment and management ofrnchemical mixtures.