[en] Short-Chain Chlorinated Paraffins (SCCPs) are ubiquitous, persistent chemicals which toxicity
and potential impacts to aquatic ecosystems have been overlooked for many years. This study
aims at determining the impact of these chemicals on rotifers. As sexual reproduction is often
more sensitive to toxicants than amictic reproduction, this study focuses on endpoints
describing sexual reproduction and on the impact on the gene expression of three receptors
associated or suspected to be associated with reproduction the RXR, RAR and MAPR
receptors. Brachionus calyciflorus was exposed to environmental concentrations of SCCPs(10,
100 and 1000 ng/L) and the impact on sexual reproduction (mixis rate, fertilization rate, resting
egg production, gamete production) was assessed. Variations in the gene expression of RXR,
RAR and MAPR were also studied through mRNA analysis. Our results show that SCCPs
increase mixis rate but decrease fertilization rate, which leads to unaltered resting egg
production. Impacts on mRNA levels of RXR, RA and MAPR were also noted and similarities
between these biomolecular impacts and the reproduction study were observed.
