Trace analysis of benzophenone-type UV filters in water and their effects on human estrogen and androgen receptors.

To carry out risk assessments of benzophenone-type UV filters (BPs), fast and accurate analytical methods are crucial to determine and monitor levels in the environment. This study presents an LC-MS/MS method that requires minimal sample preparation and yet can identify 10 different BPs in environmental samples such as surface or wastewater resulting in a LOQ range from 2 to 1060 ng/L. The method suitability was tested through environmental monitoring, which showed that, BP-4 is the most abundant derivative found in the surface waters of Germany, India, South Africa and Vietnam. BP-4 levels correlate with the WWTP effluent fraction of the respective river for selected samples in Germany. Peak values of 171 ng/L for 4-hydroxybenzophenone (4-OH-BP), as measured in Vietnamese surface water, already exceed the PNEC value of 80 ng/L, elevating 4-OH-BP to the status of a new pollutant that needs more frequent monitoring. Moreover, this study reveals that during biodegradation of benzophenone in river water, the transformation product 4-OH-BP is formed which contain structural alerts for estrogenic activity. By using yeast-based reporter gene assays, this study provides bio-equivalents of 9 BPs, 4-OH-BP, 2,3,4-tri-OH-BP, 4-cresol and benzoate and complements the existing structure-activities relationships of BPs and their degradation products.

Assessing the endocrine disrupting potentials and genotoxicity in environmental samples from Taiwanese rivers.

BACKGROUND: Surface waters receive a variety of organic pollutants via wastewater discharge, and sediment represents a sink for hydrophobic contaminants. In this study, we used in vitro yeast-based reporter gene assays and a Bacillus subtilis Rec-assay to examine the occurrence of endocrine disrupting activities and genotoxic potentials in samples collected from three Taiwanese rivers. Levels of 51 polycyclic aromatic hydrocarbons (PAHs) in muscles of fish captured from same rivers were also analyzed to assess in vivo pollution of PAHs. RESULTS: Antagonist activities for androgen receptor and retinoid X receptor (RXR) were detected in river water extracts at environmentally relevant concentrations., and sediment extracts exhibited RXR agonist, RXR antagonist, and genotoxic potentials concurrently. Σ16 PAHs in fish muscles ranged from 44.9-242.4 ng g- 1 dry weight, representing 38 to 59% of the total 51 PAHs concentrations, and methylated PAHs of low molecular weight PAHs were often detected as well. CONCLUSION: Taiwanese river sediment samples concomitantly exhibited RXR disrupting potentials and genotoxic activities, whereas RXR agonist and antagonist activities were simultaneously detected in several dry-season sediment extracts. PAH levels in fish muscles were categorized as minimally polluted by aromatic compounds, nonetheless, the presence of methylated PAHs in muscles samples may be of concern owing to the higher toxic potentials than their parent compounds.