Cytotoxicity and molecular effects of biocidal disinfectants (quaternary ammonia, glutaraldehyde, poly(hexamethylene biguanide) hydrochloride PHMB) and their mixtures in vitro and in zebrafish eleuthero-embryos.

Frequently used biocidal disinfectants, including quaternary ammonium compounds (QAC), glutaraldehyde and poly(hexamethylene biguanide) hydrochloride (PHMB), occur in the aquatic environment but their potential effects in fish are poorly known, in particular when occurring as mixtures. To investigate their joint activity, we assessed the cytotoxicity of three QACs (BAC, barquat and benzalkonium chloride), glutaraldehyde andPHMB by the MTT assay individually, followed by assessing binary and ternary mixtures in zebrafish liver cells (ZFL) and human liver cells (Huh7). We also analysed molecular effects by quantitative PCR in vitro and in zebrafish eleuthero-embryos employing a targeted gene expression approach. QACs displayed strong cytotoxicity in both cell lines with EC