|CHAKRABORTY, PAROMITA - Srm Institute Of Science And Technology|
|SHAPPELL, NANCY - Retired ARS Employee|
|MUKHOPDYAY, MOITRAIYEE - Srm Institute Of Science And Technology|
|ONANONG, SATHAPORN - University Of Nebraska|
|RONNIE, REX - Srm Institute Of Science And Technology|
|SNOW, DANIEL - University Of Nebraska|
Submitted to: Water Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/21/2020
Publication Date: 11/23/2020
Citation: Chakraborty, P., Shappell, N.W., Mukhopadhyay, M., Onanong, S., Rex, K., Snow, D. 2020. Surveillance of plasticizers, bisphenol A, steroids and caffeine in surface water of River Ganga and Sundarban wetland along the Bay of Bengal: occurrence, sources, estrogenicity screening and ecotoxicological risk assessment. Water Research. https://doi.org/10.1016/j.watres.2020.116668.
Interpretive Summary: The River Ganga in India carries Himalayan snowmelt to the Sundarban Delta and serves as a source of freshwater for two thirds of the Indian population. Endocrine disrupting chemicals, derived from plastic pollutants, may be present in aquatic environments that receive plastic-based litter. This study measured endocrine disrupting chemicals in water samples from the River Ganga and the Sundarban wetland into which the Ganga flows. In addition, steroid hormones in, and estrogenic activity of, water samples were evaluated. Caffeine was measured as a marker for contributions from human wastewater discharges. In general, levels of endocrine disrupting pollutants were below immediate levels of concern for humans and aquatic species. Nevertheless, the identification of a few areas having elevated endocrine disruption chemical loads in the River Ganga is valuable for the design of intervention, remediation, and prevention strategies.
Technical Abstract: The transboundary River Ganga serves as a conduit for meltwater from the Himalayas and is a major freshwater source for two thirds of Indian population before emptying into the Sundarban Delta, the largest estuary in the Bay of Bengal. Endocrine disrupting compounds (EDCs) such as phthalic acid es- ters (PAEs) and bisphenol A (BPA) used as organic plastic additives can pollute the aquatic environment receiving plastic litter. Hence, we have investigated these EDCs in water samples from Ganga and Sun- darban wetland of India. Since these compounds exhibit estrogenic potential, we have further measured steroids and evaluated the estrogenic activity (estradiol equivalents, Bio E2Eqs) using an in-vitro bioassay (E-Screen). Further Bio E2Eqs were compared with the sum of predicted estradiol equivalents based on the chemical concentrations of PAEs and BPA by E-Screen ( Chem E2Eq) and YES factors ( Chem YES). Caf- feine was measured as a marker for anthropogenic wastewater discharge. Results showed that the high- est Bio E2Eq (below the lowest observable effect of E2 on fish) was associated with sites having sewer outfalls in the middle stretch of the river, and concomitantly coinciding with the elevated concentra- tions of caffeine. Neither ChemE2Eq nor Chem YES correlated with measured Bio E2Eqs. River concentra- tions of BPA (0.04–4.46 µg/L) and 7 plasticizers (0.43–7.63 µg/L) were higher than BPA (0.21–2.82 µg/L) and 7 plasticizers (0.85–2 µg/L) in the Sundarban wetland. The only steroids detected were androgens, found at four sites in Ganga (0.007 µg/L ±0.003, mean ±S.D.). The highest estimated ecotoxicological risk to aquatic insect and fish stemmed from BPA. A secondary effect, and a potential impact on hu- man health could be reflected via fish consumption from the productive fisheries region along the lower stretch of River Ganga. Identification of areas of elevated estrogenicity, plasticizer and steroid concen- trations in River Ganga can be used to design and implement interventions for the remediation of such emerging contaminants.