Evolutionary Toxicology as a Tool to Assess the Ecotoxicological Risk in Freshwater Ecosystems

Abstract

Borrowing the approaches of population genetics, evolutionary toxicology was particularly useful in assessing the transgenerational effects of a substance at sublethal concentrations, as well as evaluating genetic variation in populations exposed to pollutants. Starting from assays in controlled conditions, in recent years this approach has also found successful applications multi-stressed natural systems. It is also able to exploit the huge amount of data provided by Next Generation Sequencing (NGS) techniques. Similarly, the focus has shifted from effects on the overall genetic variability, the so-called "genetic erosion", to selective effects induced by contaminants at more specific pathways. In the aquatic context, effects are usually assessed on non-model species, preferably native fish or macroinvertebrates. Here we provide a review of current trends in this specific discipline, with a focus on population genetics and genomics approaches. In addition, we demonstrate the potential usefulness of predictive simulation and Bayesian techniques. A focused collection of field and laboratory studies is discussed to demonstrate the effectiveness of this approach, covering a range of molecular markers, different endpoints of genetic variation, and different classes of chemical contaminants. Moreover, guidelines for a future implementation of evolutionary perspective into Ecological Risk Assessment are provided.

Assessment of genotoxicity in Clarias gariepinus exposed to lethal and sub-lethal concentrations of oilfield chemicals: DNA concentration, purity, and genetic implications

“…Understanding the genetic variations induced by lethal concentrations of O-BE in Clarias gariepinus is crucial for assessing the broader environmental impact, as genetic changes in aquatic organisms can have implications for population health, adaptation, and ecosystem dynamics, potentially affecting the long-term health and stability of aquatic ecosystems (Rusconi et al, 2018;Schuijt et al, 2021).…”

A review of the bioaccumulation and adverse effects of PFAS in free-living organisms from contaminated sites nearby fluorochemical production plants

“…Second, the toxicological implication at the population scale was explored by investigating changes in population genetics of a native benthic organism (Hydropsyche modesta, Trichoptera), with the aim to highlight sub-lethal effects that can accumulate through generations and lead to fitness reduction and, potentially, population extinction. The overall ecological quality of the sites was calculated through the STAR_ICMi multimetric index, which analyzes the community structure by calculating and integrating different biotic indices, such as ASPT, Log10(Sel_EPTD + 1), 1-GOLD, total number of families, number of EPT families, and Shannon-Wiener Index [46] . The multimetric index did not show any difference between the two sampling points, which were both classified as moderate.…”