Polycyclic aromatic hydrocarbons (PAHs) are considered persistent organic pollutants and can cause serious damage in some organisms, including mutagenic and carcinogenic properties. The aim of this study was to evaluate the PAH concentrations in an urban basin and use diagnostic ratios to possible distinguish sources of contamination. The surface water analysis showed predominance of compounds containing 3 to 4 aromatic rings while in suspended particulate matter and sediment there was a predominance of compounds containing 4, 5 and 6 rings. Although present in low concentrations in the sediment, assessment of toxicity equivalent factor (TEF) showed values higher than 3 ng g -1 pellet to 50% of the samples with values of up to 125.35 ng g -1. The use of diagnostic ratios allowed verifying that the main source of PAHs in these aquatic environments, are pyrogenic sources. Still, the use of such relations should be done with caution, trying to assess possible interference of degradation factors Keywords: Diagnostic ratios; Risk assessment; Polycyclic aromatic hydrocarbons; Environmental contamination. RESUMOHidrocarbonetos policíclicos aromáticos (HPAs) são poluentes orgânicos considerados persistentes e que podem causar sérios danos em alguns organismos, incluindo propriedades mutagênicas e carcinogênicas. O objetivo desse estudo foi avaliar as concentrações de HPAs em uma bacia urbanizada e utilizar relações diagnósticas para tentar distinguir fontes de contaminação. A análise de água superficial mostrou um predomínio de compostos de 3 a 4 anéis aromáticos, enquanto que para material particulado suspenso e sedimentos houve uma predominância de compostos com 4, 5 e 6 anéis aromáticos. Apesar de baixas concentrações no sedimento, avaliação de equivalentes de toxicidade mostraram valores superiores a 3 ng g -1 de sedimento para 50% das amostras, com valores de até 125.35 ng g PAHs diagnostic ratios for the distinction of petrogenic and pirogenic sources: applicability in the Upper Iguassu Watershed -Parana, Brazil

Parabens and triclosan compounds are widely used in pharmaceutical products, personal care, food and various products of daily use. After use, the final destinations of these contaminants are domestic effluents and the environment if not collected or treated. The objective of this study was to evaluate the presence of parabens and triclosan in environments in a subtropical region, more specifically in the metropolitan region of Curitiba (southern Brazil) and possible effects of these compounds in aquatic environments through risk assessment through the use of risk quotient (RQ). Samples were collected in 20 points for 4 campaigns. For the extraction of the compounds we used the extraction technique of solid phase extraction (SPE). The determination of the compounds was using gas chromatography coupled to mass spectrometry (GC-MS). It was observed high concentrations of parabens, especially MeP (up to 2875 ng L -1). Despite high concentrations of parabens, their presence has a low risk to aquatic organisms. Triclosan has been observed at higher concentrations (415 ng L -1 ), suggesting once again that these environments are impacted by human action. The RQ assessed that triclosan has a high risk for certain groups of organisms.Keywords: Emerging pollutants; Risk assessment; Triclosan; Parabens; Domestic sewage. RESUMOParabenos e triclosan são usados amplamente na composição de produtos farmacêuticos, cuidado pessoal, alimentos e diversos produtos de uso cotidiano. Após seu uso, o destino final destes contaminantes são os efluentes domésticos e o meio ambiente, caso não seja coletado ou tratado. A presença destes poluentes emergentes podem apresentar efeitos adversos ao meio ambiente. O objetivo desse estudo foi avaliar a ocorrência de parabenos e triclosan em ambientes de uma região subtropical, mais especificamente na Região Metropolitana de Curitiba (sul do Brasil) e avaliar possíveis efeitos desses compostos em ambientes aquáticos, através da avaliação de risco através do quociente de risco (QR). Foram coletadas amostras em 20 pontos em rios da Região Metropolitana de Curitiba, durante quatro campanhas. Para a extração dos compostos, foi utilizada a técnica de extração em fase sólida (SPE), com determinação por cromatografia gasosa acoplada à espectrometria de massas (GC-MS). Foram observadas elevadas concentrações de parabenos, especialmente MeP (máximo de 2875 ng L -1 ). Apesar das concentrações elevadas de parabenos a presença dos mesmos apresentou baixo risco para os organismos aquáticos. Quanto ao triclosan, observaram-se também elevadas concentrações (415 ng L -1 ), sugerindo mais uma vez que esses ambientes encontram-se impactados pela ação humana. O valor de QR permitiu avaliar que o triclosan apresentou um elevado risco para certos grupos de organismos.

Dissolved organic carbon (DOC) is frequently used as a diagnostic parameter for the identification of environmental contamination in aqueous systems. Since this organic matter is evolving and decaying over time. If samples are collected under environmental conditions, some sample stabilization process is needed until the corresponding analysis can be made. This may affect the analysis results. This problem can be avoided using the direct determination of DOC. We report a study using in situ synchronous fluorescence spectra, with independent component analysis to retrieve relevant major spectral contributions and their respective component contributions, for the direct determination of DOC. Fluorescence spectroscopy is a very powerful and sensitive technique to evaluate vestigial organic matter dissolved in water and is thus suited for the analytical task of direct monitoring of dissolved organic matter in water, thus avoiding the need for the stabilization step. We also report the development of an accurate calibration model for dissolved organic carbon determinations using environmental samples of humic and fulvic acids. The method described opens the opportunity for a fast, in locus, DOC estimation in environmental or other field studies using a portable fluorescence spectrometer. This combines the benefits of the use of fresh samples, without the need of stabilizers, and also allows the interpretation of various additional spectral contributions based on their respective estimated properties. We show how independent component analysis may be used to describe tyrosine, tryptophan, humic acid and fulvic acid spectra and, thus, to retrieve the respective individual component contribution to the DOC.