Combined toxicity of perfluoroalkyl substances and microplastics on the sentinel species Daphnia magna: Implications for freshwater ecosystems.

Publisher: Elsevier Applied Science Publishers Country of Publication: England NLM ID: 8804476 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1873-6424 (Electronic) Linking ISSN: 02697491 NLM ISO Abbreviation: Environ Pollut Subsets: MEDLINE

Original Publication: Barking, Essex, England : Elsevier Applied Science Publishers, c1987-

Daphnia*/drug effects ; Fluorocarbons*/toxicity ; Water Pollutants, Chemical*/toxicity ; Microplastics*/toxicity ; Ecosystem* ; Alkanesulfonic Acids*/toxicity; Animals ; Sentinel Species ; Fresh Water ; Caprylates/toxicity ; Daphnia magna

Persistent chemicals from industrial processes, particularly perfluoroalkyl substances (PFAS), have become pervasive in the environment due to their persistence, long half-lives, and bioaccumulative properties. Used globally for their thermal resistance and repellence to water and oil, PFAS have led to widespread environmental contamination. These compounds pose significant health risks with exposure through food, water, and dermal contact. Aquatic wildlife is particularly vulnerable as water bodies act as major transport and transformation mediums for PFAS. Their co-occurrence with microplastics may intensify the impact on aquatic species by influencing PFAS sorption and transport. Despite progress in understanding the occurrence and fate of PFAS and microplastics in aquatic ecosystems, the toxicity of PFAS mixtures and their co-occurrence with other high-concern compounds remains poorly understood, especially over organisms' life cycles. Our study investigates the chronic toxicity of PFAS and microplastics on the sentinel species Daphnia, a species central to aquatic foodwebs and an ecotoxicology model. We examined the effects of perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and polyethylene terephthalate microplastics (PET) both individually and in mixtures on Daphnia ecological endpoints. Unlike conventional studies, we used two Daphnia genotypes with distinct histories of chemical exposure. This approach revealed that PFAS and microplastics cause developmental failures, delayed sexual maturity and reduced somatic growth, with historical exposure to environmental pollution reducing tolerance to these persistent chemicals due to cumulative fitness costs. We also observed that the combined effect of the persistent chemicals analysed was 59% additive and 41% synergistic, whereas no antagonistic interactions were observed. The genotype-specific responses observed highlight the complex interplay between genetic background and pollutant exposure, emphasizing the importance of incorporating multiple genotypes in environmental risk assessments to more accurately predict the ecological impact of chemical pollutants.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Keywords: Chemical mixtures; Chronic toxicity; Developmental failure; Microplastics; PFAS; Waterflea

0 (Fluorocarbons)
0 (Water Pollutants, Chemical)
0 (Microplastics)
0 (Alkanesulfonic Acids)
9H2MAI21CL (perfluorooctane sulfonic acid)
947VD76D3L (perfluorooctanoic acid)
0 (Caprylates)

Date Created: 20241017 Date Completed: 20241127 Latest Revision: 20241127

20241202

10.1016/j.envpol.2024.125133

39419463