The goal of this work was to investigate the occurrence of emerging contaminants in drinking water of the city of Campinas, Brazil. Tap water samples were analyzed using SPE-GC-MS for 11 contaminants of recent environmental concern. Six emerging contaminants (stigmasterol, cholesterol, bisphenol A, caffeine, estrone, and 17β-estradiol) were found in the samples. The latter two were detected only during the dry season, with concentrations below quantification limits. Stigmasterol showed the highest average concentration (0.34± 0.13µg L −1 ), followed by cholesterol (0.27±0.07µg L −1 ), caffeine (0.22±0.06µg L −1 ), and bisphenol A (0.16±0.03µg L −1 ). In Campinas, where surface drinking water supplies receive large amounts of raw sewage inputs, the emerging contaminants levels in drinking waters were higher than median values compiled for drinking and finished water samples around the world.

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A liquid chromatography-electrospray tandem mass spectrometry (LC-MS/MS) method for the determination of antibiotics in water was developed and applied to Brazilian surface waters. Amoxicillin, ampicillin, cefalexin (CEF), ciprofloxacin (CIP), norfloxacin (NOR), sulfamethoxazole, tetracycline (TET), and trimethoprim were selected as target compounds due to their high consumption pattern in Brazil. LC and MS conditions were optimized to produce the maximum analytic response for each compound. Anion exchange and polymeric solid-phase extraction cartridges, in series, were employed during the extraction procedures. Recovery, linear range, limit of detection (LOD), and limit of quantification were calculated. LOD varied from 0.13 ng L(-1) for CIP and NOR to 0.76 ng L(-1) for TET. Surface water samples from the Atibaia watershed (São Paulo State, Brazil) were analyzed. Results showed that seasonal and anthropogenic aspects dictated the levels of antibiotics in the samples. An overall frequency of detection of 55% was observed during the rainy period, whereas a higher percentage (88%) was noticed for samples collected during the dry season. In the Atibaia River, sample concentrations ranged from 29 ng L(-1) for CEF to 0.5 ng L(-1) for NOR. In a sewage-affected stream, however, concentrations up to 2422 ng L(-1) CEF were found.

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Recebido em 19/5/00; aceito em 4/10/00 APPLICABILITY OF ADSORPTION MODELS TO THE STUDY OF COPPER BEHAVIOUR IN CLAYEY SOILS. It was evaluated the applicability of Langmuir, Freundlich and Temkin models to copper adsorption in three classes of soils. Fractions of each soil were added to test tubes containing growing concentrations of the metal in solution. The tubes were shaken and the copper concentrations were determined in the extracts by atomic absorption spectrometry (AAS). The models offered a good fit for the experimental data indicating that presence of silicated clay had high influence on copper sorption. The Langmuir isotherm showed high influence of the organic matter in the absorption phenomenon. It was evidenced the importance of further studies related to Temkin model. Keywords: adsorption isotherms; heavy metal; tropical soils. Quim. Nova, Vol. 24, No. 3, 324-330, 2001. Artigo INTRODUÇÃOVarios estudos ambientais indicam que o homem tornou-se o mais importante fator no ciclo biogeoquímico de metais pesados. A mobilização destes poluentes para a biosfera tem alcançado níveis preocupantes 1 . O solo é um componente muito específico da biosfera, pois além de ser um depósito geoquímico de metais contaminantes, controla também o transporte destas substâncias para a atmosfera, a hidrosfera e a biota. A presença destes contaminantes no ambiente possibilita a bioacumulação e a biomagnificação na cadeia alimentar, proporcionando distúrbi-os nos processos metabólicos dos seres vivos. A bioacumulação e a biomagnificação encarregam-se de transformar concentrações normais em concentrações tóxicas para diferentes espécies da biota e para o próprio homem 2 . Deste modo, a poluição do solo por metais pesados tem sido reconhecida como um importante problema ambiental, podendo ocasionar riscos ainda desconhecidos para a saúde de gerações futuras 3 . O cobre, além de ser um metal pesado 4 , atende aos critérios de essencialidade para plantas e microrganismos, sendo classificado como micronutriente. A literatura 5 descreve a concentração média deste metal no solo como de 20 µg.g -1 com variações na faixa de 6 a 80 µg.g -1 , porém, pode ser acrescido ao meio por resíduos urbanos e industriais, pesticidas e fertilizantes, entre outros 2 . Em grandes concentrações, pode proporcionar efeitos tóxicos ao tecido vegetal e causar a deficiência de outros nutrientes essenciais através de interações antagônicas 6 . A dinâmica do cobre no solo é bastante complexa e altamente afetada por inúmeros fatores do meio, principalmente a composição química, física e mineralógica do solo, a quantidade de matéria orgânica e o pH 7 . Para uma melhor compreensão dos fatores que controlam o comportamento deste metal no solo, faz-se presente um breve comentário a respeito das características químicas e mineralógicas do meio em questão.O solo pode ser definido como uma mistura de materiais inorgânicos e orgânicos, formados a partir de uma série de processos operantes na superfície terrestre que ocasionam a decomposição de rochas e minerais primári...

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Estrogenic Endocrine Disrupting Chemicals (EDCs) are a concern due to their ubiquity and recognized adverse effects to humans and wildlife. Methods to assess exposure to and associated risks of their presence in aquatic environment are still under development. The aim of this work is to assess estrogenicity of raw and treated waters with different degrees of pollution. Chemical analyses of selected EDCs were performed by liquid chromatography-tandem mass spectrometry, and estrogenic activity was evaluated using in vitro bioluminescent yeast estrogen assay (BLYES). Most raw water samples (18/20) presented at least one EDC and 16 rendered positive in BLYES. When EDCs were detected, the bioassay usually provided a positive response, except when only bisphenol A was detected at low concentrations. The highest values of estrogenic activity were detected in the most polluted sites. The maximum estrogenic activity observed was 8.7 ng equiv. of E2 L(-1). We compared potencies observed in the bioassay to the relative potency of target compounds and their concentrations failed to fully explain the biological response. This indicates that bioassay is more sensitive than the chemical approach either detecting estrogenic target compounds at lower concentrations, other non-target compounds or even synergistic effects, which should be considered on further investigations. We have not detected either estrogenic activity or estrogenic compounds in drinking water. BLYES showed good sensitivity with a detection limit of 0.1 ng equiv. E2 L(-1) and it seems to be a suitable tool for water monitoring.