Ecotoxicity of disinfectant benzalkonium chloride and its mixture with antineoplastic drug 5-fluorouracil towards algaPseudokirchneriella subcapitata

Abstract

BackgroundBenzalkonium chloride (BAC) is one of the most common ingredients of the disinfectants. It is commonly detected in surface and wastewaters where it can interact with the residues of pharmaceuticals that are also common wastewater pollutants. Among the latter, the residues of antineoplastic drugs are of particular concern as recent studies showed that they can induce adverse effect in aquatic organisms at environmentally relevant concentrations.MethodsEcotoxicity of BAC as an individual compound and in a binary mixture with an antineoplastic drug 5-fluorouracil (5-FU) was determined towards alga Pseudokirchneriella subcapitata, a representative of primary producers. The toxicity of the BAC+5-FU binary mixture was predicted by the two basic models: concentration addition (CA) and independent action (IA), and compared to the experimentally determined toxicity. Additionally combination index (CI) was calculated to determine the type of interaction.ResultsAfter 72 h exposure to BAC a concentration dependent growth inhibition of P. subcapitata was observed with an EC50 0.255 mg/L. Comparing the predicted no effect concentration to the measured concentrations in the surface waters indicate that BAC at current applications and occurrence in aquatic environment may affect algal populations. The measured toxicity of the mixture was higher from the predicted and calculated CI confirmed synergistic effect on the inhibition of algal growth, at least at EC50 concentration. The observed synergism may have impact on the overall toxicity of wastewaters, whereas it is less likely for general environments because the concentrations of 5-FU are several orders of magnitude lower from its predicted no effect concentration.DiscussionThese results indicate that combined effects of mixtures of disinfectants and antineoplastic drugs should be considered in particular when dealing with environmental risk assessment as well as the management of municipal and hospital wastewaters.

Increased Use of Quaternary Ammonium Compounds during the SARS-CoV-2 Pandemic and Beyond: Consideration of Environmental Implications

“…Acute toxic effects on marine bacteria of the Vibrionaceae family, however, have already been observed at high μg/L concentrations (EC50 = 57–630 μg/L). , The largest number of toxicity studies with QACs over the past 20 years were performed with various algae species. Typical acute toxicity thresholds (EC50–96h) were between 0.1 and 1.8 mg/L. ,− Large variations were observed between different algae species, as well as for different endpoints and QAC structures. Overall, the toxicity of QACs toward algae increased with exposure time and with chain lengths of ATMACs and BACs but not with chain lengths of DADMACs. , Aquatic organisms also frequently studied are protozoa, daphnids, and fish.…”

Benzalkonium Chlorides: Uses, Regulatory Status, and Microbial Resistance

“…In a 2006 report, the EPA recognized the toxicity of BACs to the aquatic environment and its inhabitants, such as fish, oysters, shrimp, and invertebrates, advising against the release of BACs into lakes, oceans, or other waters (3). Since then, their toxicity to aquatic organisms, as well as other animals, has been well established by several research groups (30,31). Despite that, BACs have been detected in wastewater effluents and other environments ( Table 1).…”

Microencapsulation of benzalkonium chloride enhanced its antibacterial and antibiofilm activities against Listeria monocytogenes and Escherichia coli

“…The extensive use of QACs in domestic and industrial applications has outcompeted its biodegradation in the environment, which results in its enrichment in wastewaters and aquatic environment. When the concentration of some QACs excesses certain level in the environment, they become ecotoxic (Elersek et al 2018). Therefore, there is a growing concern on the presence of QACs in the environment, and the reduction of usage of QACs should be a good study direction.…”