title: Evolutionary toxicology: Meta-analysis of evolutionary events in response to chemical stressors.
abstract: The regulatory decision-making process regarding chemical safety is most often informed by evidence based on ecotoxicity tests that consider growth, reproduction and survival as end-points, which can be quantitatively linked to short-term population outcomes. Changes in these end-points resulting from chemical exposure can cause alterations in micro-evolutionary forces (mutation, drift, selection and gene flow) that control the genetic composition of populations. With multi-generation exposures, anthropogenic contamination can lead to a population with an altered genetic composition, which may respond differently to future stressors. These evolutionary changes are rarely discussed in regulatory or risk assessment frameworks, but the growing body of literature that documents their existence suggests that these important population-level impacts should be considered. In this meta-analysis we have compared existing contamination levels of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) that have been documented to be associated with evolutionary changes in resident aquatic organisms to regulatory benchmarks for these contaminants. The original intent of this project was to perform a meta-analysis on evolutionary events associated with PCB and PAH contamination. However, this effort was hindered by a lack of consistency in congener selection for "total" PCB or PAH measurements. We expanded this manuscript to include a discussion of methods used to determine PCB and PAH total contamination in addition to comparing regulatory guidelines and contamination that has caused evolutionary effects. Micro-evolutionary responses often lead populations onto unique and unpredictable trajectories. Therefore, to better understand the risk of population-wide alterations occurring, we need to improve comparisons of chemical contamination between affected locations. In this manuscript we offer several possibilities to unify chemical comparisons for PCBs and PAHs that would improve comparability among evolutionary toxicology investigations, and with regulatory guidelines. In addition, we identify studies documenting evolutionary change in the presence of PCB and PAH contamination levels below applicable regulatory benchmarks.
authors.affiliation: Department of Environmental Science, Center for Reservoir and Aquatic Systems Research (CRASR), Institute for Biomedical Studies, Baylor University, Waco, TX, 76798, USA.
authors.forename: Elias
authors.initials: E
authors.lastname: M Oziolor
authors.affiliation: Laboratory of Environmental Toxicology and Aquatic Ecology, GhEnToxLab unit, Ghent University, Jozef Plateaustraat 22, Gent, B-9000, Belgium.
authors.forename: Karel
authors.initials: K
authors.lastname: De Schamphelaere
authors.affiliation: Department of Environmental Science, Center for Reservoir and Aquatic Systems Research (CRASR), Institute for Biomedical Studies, Baylor University, Waco, TX, 76798, USA. cole_matson@baylor.edu.
authors.forename: Cole W
authors.initials: CW
authors.lastname: Matson
mesh_terms: D054750:Ecotoxicology; D004784:Environmental Monitoring; D004785:Environmental Pollutants; D011078:Polychlorinated Biphenyls; D011084:Polycyclic Aromatic Hydrocarbons
chemical_list: D004785:Environmental Pollutants; D011084:Polycyclic Aromatic Hydrocarbons; D011078:Polychlorinated Biphenyls
keywords: Evolutionary toxicology; Micro-evolution; Polychlorinated biphenyls; Polycyclic aromatic hydrocarbons