Endocrine Disruptor Impacts on Fish From Chile: The Influence of Wastewaters

Indexación ScopusIndustrial wastewaters and urban discharges contain complex mixtures of chemicals capable of impacting reproductive performance in freshwater fish, called endocrine-disrupting compounds (EDCs). In Chile, the issue was highlighted by our group beginning over 15 years ago, by analyzing the impacts of pulp and paper mill effluents (PPME) in the Biobio, Itata, and Cruces River basins. All of the rivers studied are important freshwater ecosystems located in the Mediterranean region of Central Chile, each with a unique fish biodiversity. Sequentially, we developed a strategy based on laboratory assays, semicontrolled-field experiments (e.g., caging) and wild fish population assessments to explore the issue of reproductive impacts on both introduced and native fish in Chile. The integration of watershed, field, and laboratory studies was effective at understanding the endocrine responses in Chilean freshwater systems. The studies demonstrated that regardless of the type of treatment, pulp mill effluents can contain compounds capable of impacting endocrine systems. Urban wastewater treatment plant effluents (WWTP) were also investigated using the same integrated strategy. Although not directly compared, PPME and WWTP effluent seem to cause similar estrogenic effects in fish after waterborne exposure, with differing intensities. This body of work underscores the urgent need for further studies on the basic biology of Chilean native fish species, and an improved understanding on reproductive development and variability across Chilean ecosystems. The lack of knowledge of the ontogeny of Chilean fish, especially maturation and sexual development, with an emphasis on associated habitats and landscapes, are impediment factors for their conservation and protection against the threat of EDCs. The assessment of effects on native species in the receiving environment is critical for supporting and designing protective regulations and remediation strategies, and for conserving the unique Chilean fish biodiversity. © Copyright © 2021 Barra, Chiang, Saavedra, Orrego, Servos, Hewitt, McMaster, Bahamonde, Tucca and Munkittrick.https://www.frontiersin.org/articles/10.3389/fendo.2021.611281/ful

Increased mercury and body size and changes in trophic structure of Gambusia puncticulata (poeciliidae) along the Almendares River, Cuba

The Almendares River is the largest river draining the area around Havana City, Cuba. The watershed is heavily populated and industrialized, which has had a significant impact on the flow and water quality of the river. The main goal of this study was to analyze the spatial variability in dietary habits, nutrient flow (using stable isotope ratios δ15N and δ13C), and mercury (Hg) levels along the Almendares River upstream and downstream of point-source discharges using localized fish Gambusia puncticulata. Stomach contents of G. puncticulata were similar among these sites. However, mean δ15N values ranged from 6 to 18 % across sites and were lower in fish from downstream than upstream sites, suggesting localized influences of nutrient inputs along the river. δ13C values were between -22 and -25 %, except at a mid-basin site (- 26 to -27%), indicating that fish relied on similar carbon sources at most sites. Total mercury concentrations ranged from 0.04 to 0.49 lg/g wet weight whole body and were unrelated to the among-site differences in δ15N, but Hg exceeded the threshold considered to be protective of fish health (0.2 lg/g ww whole body) in the majority of fish from all sites but one. Results of this study indicate that although the dietary habits of this species do not vary across sites, tissue differences in δ15N, δ13C and Hg show little movement of this species among sites. Localized effects of human activities on nutrients and metals may be affecting the health of this species and posing a risk to other consumers in the ecosystem. © Springer Science+Business Media, LLC 2012