Risks of benzalkonium chlorides as emerging contaminants in the environment and possible control strategies from the perspective of ecopharmacovigilance

An unprecedented increase in the use of disinfection products triggered by the coronavirus disease 2019 (COVID19) pandemic is resulting in aggravating environmental loads of disinfectants as emerging contaminants, which has been considered a cause for worldwide secondary disasters. This review analyzed the literature published in the last decade about occurrence, bioaccumulation, and possible environmental risks of benzalkonium chlorides (BKCs) as emerging contaminants. Results indicated that BKCs globally occurred in municipal wastewater, surface water, groundwater, reclaimed water, sludge, sediment, soil, roof runoff, and residential dust samples across 13 countries. The maximum residual levels of 30 mg/L and 421 mu g/g were reported in water and solid environmental samples, respectively. Emerging evidences suggested possible bioaccumulation of BKCs in plants, even perhaps humans. Environmentally relevant concentrations of BKCs exert potential adverse impacts on aquatic and terrestrial species, including genotoxicity, respiratory toxicity, behavioural effects and neurotoxicity, endocrine disruption and reproductive impairment, phytotoxicity, etc. Given the intrinsic biocidal and preservative properties of disinfectants, the inductive effects of residual BKCs in environment in terms of resistance and imbalance of microorganisms have been paid special attention. Considering the similarities of disinfectants to pharmaceuticals, from the perspective of ecopharmacovigilance (EPV), a well-established strategy for pharmaceutical emerging contaminants, we use the control of BKC pollution as a case, and provide some recommendations for employing the EPV measures to manage environmental risks posed by disinfectant emerging contaminants.

Automated summary

The increased use of disinfection products during the COVID-19 pandemic has led to a rise in environmental contamination by disinfectants, which is considered a major global concern. This review focuses on the occurrence, bioaccumulation, and potential environmental risks of benzalkonium chlorides (BKCs) as emerging contaminants. The study found that BKCs were present in various environmental samples across 13 countries, including municipal wastewater, surface water, groundwater, reclaimed water, and sediment. The high levels of BKCs in water and solid environmental samples pose potential adverse effects on aquatic and terrestrial species, and may even bioaccumulate in plants and humans. Additionally, the residual BKCs in the environment can disrupt microbial balance and induce resistance. Taking lessons from the management of pharmaceutical emerging contaminants, the review suggests using the approach of ecopharmacovigilance (EPV) to address the environmental risks posed by disinfectant emerging contaminants.