Selected chloro and bromo derivatives of triclosan--syntheses and their occurrence in Canadian sewage and biosolid samples.

The occurrence of triclosan (TCS), a general purpose antibacterial agent contained in numerous consumer and personal-care products, in the aquatic environment is well known. To a lesser degree, the formation of chlorinated and brominated derivatives of TCS during the chlorination of the antibacterial has also been reported. Presumably due to the lack of authentic standards, very few reports have been published on the levels of these halogenated TCSs in the environment. For this purpose, we have synthesized six selected halogenated derivatives of TCS, namely, 3-Cl-, 5-Cl-, 3,5-Cl2-, 3-Br-, 5-Br-, and 3,5-Br2- TCSs, with supporting (1)H-NMR (nuclear magnetic resonance) and GC-MS (gas chromatography-mass spectrometry) data for their structural assignments. Using these model compounds together with sensitive analytical methods, we were able to identify and quantify the above compounds together with their precursor compound TCS in Canadian municipal wastewater and biosolid samples for the first time. While detected in all influent (range from 1.4 to 24.1 ng L(-1)) and biosolid (range from 7.7 to 274 ng g(-1)) samples, the concentrations of these chlorinated TCS were generally from 100- to 1,000-fold lower than TCS in the same sample. Even lower levels (<20 ng/g in 85% of the results) of brominated TCS were found in biosolids, and they were mostly undetected in sewage.

Evaluating the potential of effluents and wood feedstocks from pulp and paper mills in Brazil, Canada, and New Zealand to affect fish reproduction: chemical profiling and in vitro assessments.

This study investigates factors affecting reproduction in fish exposed to pulp and paper mill effluents by comparing effluents from countries with varying levels of documented effects. To explore the hypothesis of wood as a common source of endocrine disrupting compounds, feedstocks from each country were analyzed. Analyses included in vitro assays for androgenic activity (binding to goldfish testis androgen receptors), estrogenic activity (yeast estrogen screen), and neurotransmitter enzyme inhibition (monoamine oxidase and glutamic acid decarboxylase). Chemical analyses included conventional extractives, known androgens, and gas chromatograph index (GCI) profiles. All effluents and wood contained androgenic activity, particularly in nonpolar fractions, although known androgens were undetected. Effluents with low suspended solids, having undergone conventional biotreatment had lower androgenic activities. Estrogenic activity was only associated with Brazilian effluents and undetected in wood. All effluents and wood inhibited neurotransmitter enzymes, predominantly in polar fractions. Kraft elemental chlorine free mills were associated with the greatest neurotransmitter inhibition. Effluent and wood GCI profiles were correlated with androgenic activity and neurotransmitter enzyme inhibition. Differences in feedstock bioactivities were not reflected in effluents, implying mill factors mitigate bioactive wood components. No differences in bioactivities could be discerned on the basis of country of origin, thus we predict effluents in regions lacking monitoring would affect fish reproduction and therefore recommend implementing such programs.

In vivo and in vitro mixed-function oxygenase activity and vitellogenin induction in fish and in fish and rat liver cells by stilbenes isolated from scotch pine (Pinus sylvestris).

Many types of pulp and paper mill effluents have the ability to induce mixed-function oxygenase (MFO) activity and vitellogenin (VTG) protein in exposed male fish. The search for the compounds responsible for MFO induction has led to several classes of compounds, among them retene and stilbenes. The objective of this study was to investigate the biological activities of candidate stilbene compounds. Three stilbenes, 3,5-dihydroxystilbene (pinosylvin; P1), 3-hydroxy-5-methoxystilbene (P2), and 3,5-dimethoxystilbene (P3), were extracted from Scotch pine (Pinus sylvestris) and purified to evaluate their ability to induce MFO activity in vitro using ethoxyresorufin-O-deethylase (EROD) activity in a rat hepatoma cell line (H4IIE). As these compounds may be chlorinated during pulp bleaching, chlorination of P2 was undertaken, producing di- and trichlorinated isomers (Cl-P2), which were also tested. Compounds were tested for EROD-inducing ability in vivo by exposing juvenile rainbow tout (Oncorhynchus mykiss) to waterborne concentrations (0.010 to 1.0 mg/L) for 4 days. Compounds were also tested for their ability to induce VTG in trout primary liver cells in vitro. The stilbenes were weak inducers of EROD and VTG. H4IIE EROD was induced by all four compounds, with the most potent induction by P3, followed by P1, the Cl-P2 mixture, and then P2. Induction for all four stilbenes was from 3.13 × 10⁻³ to 3.57 × 10⁻4 as potent as retene and about 1.11 × 10⁻5 to 1.20 × 10⁻6 as potent as TCDD. Juvenile rainbow trout did not show EROD induction after exposures to P1, P2, or the Cl-P2 mixture, whereas P3 caused activity fourfold above that of controls. P1, P3, and Cl-P2 all weakly induced VTG in rainbow trout hepatocytes. The most potent inducer of VTG was Cl-P2, followed by P3 and P1. The results show the ability of wood-derived stilbenes to cause weak MFO induction in fish and in rat liver cells and to weakly induce vitellogenin in fish liver cells.