Contribution of pharmaceuticals and personal care products (PPCPs) to whole toxicity of water samples collected in effluent-dominated urban streams.

Water samples were collected from effluent-dominated urban streams in Tokushima, Kyoto, and Saitama in Japan to roughly determine the contribution of pharmaceuticals and personal care products (PPCPs) and surfactants to whole toxicity of the water. Approximately 100 PPCPs including anionic surfactants such as linear alkylbenzene sulfonate (LAS), were chemically analyzed. Using 14 water samples, chronic or sub-chronic toxicity tests were conducted on three aquatic species, the green alga Raphidocelis subcapitata, the cladoceran Ceriodaphnia dubia, and the zebrafish Danio rerio. Bioassays for the selected individual PPCPs were conducted using the three species. Assuming the concentration addition (CA) model, the contribution of each PPCP to the whole toxicity of the riverwater was estimated based on toxicity unit (TU). The contribution of PPCPs, which primarily consists of a few antibiotic agents such as triclosan and clarithromycin, ranged from 0.9% to 69% of the whole toxicity of the water samples for algae, whereas the selected LAS congeners accounted for at most 5.3%. In contrast, the contribution of LAS ranged from 0.067% to 86% and from 0.021% to 27% of the whole toxicity for cladoceran and zebrafish, respectively, whereas that of PPCPs for these species was at most 2.1% at all sampling points. Our results suggest a limited contribution of PPCPs except for antimicrobial agents and the possible substantial contribution of LAS to toxicity in cladocerans and zebrafish.

Ecotoxicity and screening level ecotoxicological risk assessment of five antimicrobial agents: triclosan, triclocarban, resorcinol, phenoxyethanol and p-thymol.

Acute and chronic (or sub-chronic) toxicity of five selected antimicrobial agents, including triclosan (TCS), triclocarban (TCC), resorcinol, phenoxyethanol and p-thymol, was investigated using the conventional three-aquatic-organism battery. These compounds are widely used in cosmetics and other personal care products and their ecological risk has recently become a significant concern. As results of toxicity tests, TCS was found to be most strongly toxic for green algae [e.g. 72 h no observed effect concentration (NOEC) of 0.50 µg l(-1) ] among the selected compounds, followed by TCC, while TCC was more toxic or similar to TCS for Daphnia and fish (e.g. Daphnia 8 day NOEC of 1.9 µg l(-1) ). Having compared the predicted no effect concentration (PNEC) determined from the toxicity data with measured environmental concentrations (MEC), the preliminary ecological risk assessment of these five antimicrobials was conducted. The MEC/PNEC ratios of TCS and TCC were over 1 for some monitoring data, especially in urban streams with watershed areas without sewage service coverage, and their potential risk for green algae and Daphnia might be at a level of concern, although the contribution of TCS/TCC on the total toxicity of the those sites needs to be further investigated. For the three other antimicrobials, the maximum MEC/PNEC ratio for resorcinol was 0.1-1, but those for phenoxyethanol and p-thymol were <0.1 and their risk to aquatic organisms is limited, although the additive effects with TCS, TCC and other antimicrobial agents, such as parabens, need to be further examined in future studies.