Abstract
The emerging contaminant 4-nonylphenol is an active ingredient in many surfactants. Though 4-nonylphenol has been reported in Mexican waterbodies, no stringent law is available to establish its permissible limits. Most ecotoxicological assays using zooplankton species are based on previously unexposed populations, and multigenerational experiments are rare. Plationus patulus and Brachionus havanaensis are widely distributed species in Mexico and have been used in ecotoxicological assessments. In this work, the median lethal concentration of 4-nonylphenol (LC50, 24 h) for both rotifer species was derived. Based on our acute toxicity data (24 h LC50 of 4-nonylphenol for P. patulus and B. havanaensis were 500 and 250 µg L−1, respectively), three sublethal concentrations (µg L−1) (7.81, 15.82 and 31.25 for B. havanaensis and 15.62, 31.25 and 62.5 for P. patulus) were used in the life table demography tests for two successive generations (F0 and F1) of either rotifer species. Regardless of the concentrations used, 4-nonylphenol had an adverse effect on both rotifer species over two successive generations. P. patulus was more sensitive than B. havanaensis in chronic toxicity tests. F1 generation of both rotifer species was far more adversely affected than the F0 in all toxicant treatments.
Acknowledgments
One of us (B.K.G.P.) received a doctoral scholarship from CONACYT (No. 492489) through the Postgraduate Programme of Biological Sciences and Health of the Metropolitan Autonomous University, Xochimilco (UAM-X). B.K.G.P. thanks Manuel Aaron Gayosso Morales for help during field collections. S.S.S.S. and S.N. are grateful to PAPIIT (IG 200820) for additional support.
Data availability
All the raw data will be available for anyone with a request to the authors.