Seasonal occurrence and risk assessment of pharmaceutical and personal care products in Bengaluru rivers and lakes, India

Water samples were collected from 35 locations in the Arkavathi river, its tributaries and lakes spread across the Bengaluru metropolitan area in Southern India during monsoon (October 2018) and post-monsoon (February 2019) seasons. Eleven pharmaceutical and personal care products (PPCPs) (sulfamethoxazole, chloramphenicol, ethyl paraben, diclofenac, propylparaben, ibuprofen, BP-1, oxybenzone, bisphenol A, triclosan, triclocarban) were investigated for their occurrence, seasonal variation, and toxicological effects on the biota. The PPCPs belong to different classes like non-steroidal anti-inflammatory drugs, antibiotics, antibacterials, UV-filters, plasticizer, and preservatives. Ibuprofen was present in high concentrations (1834 ng/L) followed by triclosan (1761 ng/L) and diclofenac (1130 ng/L) in the river. Samples collected during monsoon season had lower concentrations of sulfamethoxazole, chloramphenicol and diclofenac whereas rest of the target analytes had lower concentrations during post-monsoon season. Dilution in monsoon season and adsorption to the sediments in the post-monsoon season can be the possible reasons for the seasonal variability. The highest detection frequencies of PPCPs at the Arkavathi river indicates the continuous discharge of wastewater from highly populated metropolitan and industrial areas. The ecotoxicity data for diclofenac and triclosan suggest high risk (Hazard Quotient >1) for various species of fish and algae observed from the Kumbalagodu (S20) and Shanumangala (S19) stations respectively from the mid-stream of Arkavathi river. It was followed by bisphenol A with a hazard quotient of 0.88 in Banashankari (S25) that can affect specific species of fish. No human health risk assessment was estimated from the identified sampling stations. This is the first report on seasonal occurrence of PPCPs with their associated toxicological studies from the Arkavathi river, its tributaries, and lakes across the Bengaluru metropolis. [Display omitted] •First study reporting PPCPs from Arkavathi river, its tributaries and lakes.•Detection frequency ranged from 0% to 69% for target analytes.•Ibuprofen, diclofenac and triclosan were detected at high concentrations.•Water dilution, sorption and biotransformation caused seasonal variations in PPCPs.•Hazard quotient for PPCPs indicated that the fish and algae are at risk.