We investigated water quality at an advanced water reclamation plant and three conventional wastewater treatment plants using an "ecotoxicity toolbox" consisting of three complementary analyses (chemical analysis, in vitro bioanalysis and in situ biological monitoring), with a focus on endocrine disruption. The in vitro bioassays were chosen to provide an appropriately wide coverage of biological effects relevant to managed aquifer recharge and environmental discharge of treated wastewater, and included bioassays for bacterial toxicity (Microtox), genotoxicity (umuC), photosynthesis inhibition (Max-I-PAM) and endocrine effects (E-SCREEN and AR-CALUX). Chemical analysis of hormones and pesticides using LCMSMS was performed in parallel to correlate standard analytical methods with the in vitro assessment. For two plants with surface water discharge into open drains, further field work was carried out to examine in situ effects using mosquitofish (Gambusia holbrooki) as a bioindicator species for possible endocrine effects. The results show considerable cytotoxicity, phytotoxicity, estrogenicity and androgenicity in raw sewage, all of which were significantly reduced by conventional wastewater treatment. No biological response was detected to RO water, suggesting that reverse osmosis is a significant barrier to biologically active compounds. Chemical analysis and in situ monitoring revealed trends consistent with the in vitro results: chemical analysis confirmed the removal trends observed by the bioanalytical tools, and in situ sampling did not reveal any evidence of endocrine disruption specifically due to discharge of treated wastewater (although other sources may be present). Biomarkers of exposure (in vitro) and effect (in vivo or in situ) are complementary and together provide information with a high level of ecological relevance. This study illustrates the utility of combining multiple lines of evidence in the assessment of water quality.

SUMM.'VRYMany hypotheses have been developed to explain the adaptive nature of insect galls. One of these, the nutrition hypothesis, states that gall formers have advantages over other insects because gall tissue provides a better (higher quality) food source than unmodified tissue. However, this has rarely been experimentally tested. In a test of this hypothesis, we grew plants of Cirsium arvense (L.) Scop, tn a factorial design with two main treatments: the addition of nitrogen (to enhance foliar N levels) and of fungicide (to reduce colonization of roots by arbuscular mycorrhizal fungi). Mycorrhizal fungi have been shown previously to reduce the X concentration of host plants. Plants were exposed to adult gall flies, Urophora cardui L., and maintained through one season to allow maturation of galls.Reduction of the percentage mycorrhizal colonization by fungicide resulted in an elevation of total stem N comparable to that achie\'ed by X addition, but gall N concentration remained unchanged in all treatments. Nitrogen application elevated stem N levels when mycorrhizal fungi were present, but apphcation of both compounds together did not result in any increase over either single treatment. Fungicide application resulted in larger galls, which contained more lar\-al chambers, with more live, and heavier, larvae. However, the main effects of N were not significant, as N addition only increased fly performance on plants where mycorrhizas were not reduced.It is suggested that U. cardui gall inhabitants can manipulate N at an optimal level and thus might conform to a modified version of the nutrition hypothesis. Mycorrhizal colonization might reduce gall fly performance by delaying the appearance, or impairing the quality, of secondary nutritive tissue in the gall. Future tests of the nutrition hypothesis should include a consideration of the plant's mycorrhizal status.

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The widespread aquatic pollutant nonylphenol has been found to induce long-term and transgenerational effects in the Pacific oyster Crassostrea gigas that have not previously been reported. Evidence is provided demonstrating that when larvae are exposed to environmentally relevant concentrations of nonylphenol for a single 48 h exposure at a key stage in their development, long-term sexual developmental effects are induced. Data provided by this study suggest that exposure to 1 and 100 µg l -1 nonylphenol at Days 7 to 8 post-fertilization results in a change in the sex ratio towards females and an increase in the incidence of hermaphroditism (10 mo later, up to 30% of the resulting adults were fully functional hermaphrodites). Gamete viability is also affected, resulting in poor embryonic and larval development (up to 100% mortality) of the subsequent generation.