In this work we developed a promising analytical method combining Fourier transform near-infrared (FT-NIR) spectroscopic technique and first-order multivariate calibration using partial least-squares (PLS) model to simultaneously quantify the main greenhouse gases (GHG’s): methane (CH4), carbon dioxide (CO2), nitrous oxide (N2O) and water vapor (H2O). The models were built using 70 mixtures with different concentration of these gases, 0.25-32.0 ppm to CH4 and N2O, and 50-1100 ppm to CO2 and different values of relative humidity (52-85%, 20 ºC) in synthetic air. After preparing each of the mixtures, they were analyzed by using FT-NIR and a reference analytical technique based on gas chromatography with mass spectrometric detection (GC-MS). The FT-NIR spectrometer was coupled with a long optical path cell, with 105.6 meters of optical path. In sequence, the spectra of all mixtures and its concentration values for each gas were used to build the multivariate calibration models, using PLS regressions. For this, the mixtures were grouped with Kennard Stone algorithm, 50 samples to calibration set and 20 samples to prediction set. The values of RMSEP (root mean square error of prediction) obtained for each model are 0.66, 28.7 and 0.66 ppm, respectively, for CH4, CO2, and N2O. The limits of quantification (LOQ) for each PLS models are 0.26, 3.6, and 0.99 ppm, respectively, for CH4, CO2, and N2O. The results show the potentiality of application of this system to monitoring emission sources in which the concentration of these gases are relatively high, as urban centers, industrial areas, and landfills.

Emerging contaminants have been considered one of the main concerns for ensuring the quality of water around the world. This work presents the results of 10 years of analyses carried out in the state of São Paulo (Brazil) that has the high population density and intense agricultural and industrial activities. In this work 58 compounds (9 hormones, 14 pharmaceuticals and personal care products, 8 industrial compounds, 17 pesticides and 10 illicit drugs) were determined from 2006 to 2015 in 708 samples including raw and treated sewage, surface and ground and drinking waters. A preliminary risk assessment for aquatic life protection identified potential risks for caffeine, paracetamol, diclofenac, 17α-ethynylestradiol, 17β-estradiol, estriol, estrone, testosterone, triclosan, 4-n-nonylphenol, bisphenol A, atrazine, azoxystrobin, carbendazim, fipronil, imidacloprid, malathion and tebuconazole. Drinking water criteria were available only for 22 compounds and for them no adverse effects were expected at the concentrations found, except for 17β-estradiol.

The distribution of consumed cocaine in the Brazilian Federal District (FD) was estimated using the wastewater-based epidemiology (WBE) approach. Sewage samples from eight wastewater treatment plants were analyzed for cocaine (COC) and benzoylecgonine (BE) using solid-phase extraction followed by liquid chromatography-mass spectrometry. The highest per capita consumption was noticed for the northern area of the Brazilian Capital (1162 mg day-1 1000 inh-1) being 32% higher than the average consumption rate of the investigated region. In this area, a day-to-day investigation revealed an average cocaine consumption of 1800 mg day-1 1000 inh-1 during the weekend, i.e., more than 50% higher than weekdays. An annual street-grade cocaine load of about 2 ton was estimated for the FD considering previous information on the actual purity of seized street drugs as well as consumers between 15 and 64 years old. Sample preservation strategies were also investigated in order to expand the WBE approach to other Brazilian areas. Sample acidification to pH 2.0 presented the smallest relative errors for COC (+11%) and BE (−4%) after a period of three days under typical transport conditions practiced by the Brazilian national postal service.

Direct measurements of Redox Potential (ORP) have been used to infer the degree of electrons availability in waters, wastewaters, sediments and soils. Although the interpretation of the results obtained in direct measurements is not trivial, this parameter is part of a list of compulsory determinations required by many Environmental State Agencies as well as consulting companies. Nonetheless, the vast majority of E H reported values are not corrected to the reference electrode used, what makes most of the data incomparable with the literature, and not suitable for a correct environmental diagnostics.

Este é o primeiro trabalho que relata a ocorrência de resíduos de cocaína (COC) e benzoilecgonina (BE) em amostras coletadas em seis estações de esgoto diferentes (ETE) instaladas no Distrito Federal (DF) do Brasil. As concentrações de BE nos afluentes de esgoto foram utilizadas para calcular o consumo de cocaína (kg ano-1 por 1000 habitantes) em cada uma das regiões atendidas pelas ETE, em duas campanhas de amostragem (março e junho de 2010). Dentre as ETE estudadas, amostras provenientes de Samambaia apresentaram as maiores concentrações (de 3866 a 2477 ng L-1 de BE e 805 a 579 ng L-1 de COC) e doses por habitante (mais de 13 doses habitante-1 por ano). A extrapolação para toda a população do DF indica um consumo anual alcançando 1,0 tonelada de cocaína base livre, ou 1,1 tonelada de cloridrato de cocaína. Este trabalho também aborda a influência da forma de apresentação da cocaína (base livre ou sal cloridrato) e a integração com resultados de perfil químico na busca de estimativas mais realistas, principalmente no que se refere aos pontos de vista da criminalística e da segurança pública.

This is the first report on the occurrence of cocaine (COC) and benzoylecgonine (BE) residues in six samples collected from different wastewater treatment plants (WTP) located in the Brazilian Federal District (FD). Concentrations of BE in the influent sewage were used to calculate cocaine consumption (kg year-1 per 1000 inhabitants) for each region attended by the WTP from two sampling campaigns (March and June, 2010). Among the WTP studied, samples from Samambaia showed higher concentrations (from 3866 to 2477 ng L-1 of BE and 805 to 579 ng L-1 of COC) and doses per inhabitants (more than 13 doses inhabitant-1 per year). The extrapolation to the whole FD population points out to an annual consumption reaching 1.0 ton of free base cocaine, or 1.1 tons of cocaine hydrochloride. The work also addresses the influence of the cocaine presentation form (free base or hydrochloride) and the integration with chemical profiling results in a more realistic estimate, mainly concerning the viewpoints of forensics and law enforcement.

Um método foi otimizado usando extração em fase sólida (SPE) e cromatografia líquida de alta eficiência (HPLC) com detecção por ultravioleta com arranjo de diodos (UV/DAD) ou fluorescência (FLD) para a determinação de 15 contaminantes emergentes em águas superficiais, a saber: acetoaminofenol, ácido salicílico, diclofenaco, ibuprofeno, cafeína, 17β-estradiol, estrona, progesterona, 17α-etinilestradiol, levonorgestrel, dietilftalato, dibutilftalato, 4-octilfenol, 4-nonilfenol e bisfenol A. Os parâmetros de qualidade do método proposto mostraram a linearidade com r² > 0,996, coeficiente de variação menor que 5%, recuperações entre 80 e 120% para Milli-Q fortificada com 10 µg L-1 de cada um dos quinze compostos. O menor limite de detecção (LOD) foi 38 ng L-1 para cafeína e o maior 170 ng L-1 para ibuprofeno. O método foi aplicado para o monitoramento espacial e sazonal destes compostos na bacia do rio Atibaia, principal manancial de abastecimento público da cidade de Campinas-SP, Brasil. Dentre os 15 contaminantes emergentes estudados, 10 foram detectados em pelo menos uma amostra. A menor concentração determinada foi de 0,096 µg L-1 para o diclofenaco e a maior foi de 127 µg L-1 para cafeína.

A single run optimization chromatographic method for the determination of 15 emerging contaminants in surface water was optimized using solid-phase extraction (SPE) and high performance liquid chromatography (HPLC) with detection through ultraviolet-diode array (UV-DAD) or fluorescence (FLD). Selected compounds included acetaminophen, acetylsalicylic acid, diclofenac, ibuprofen, caffeine, 17β-estradiol, estrone, progesterone, 17α-ethynylestradiol, levonorgestrel, diethylphthalate, dibutylphthalate, 4-octylphenol, 4-nonylphenol and bisphenol A. Quality parameters of the proposed method showed a linearity r² > 0.996, coefficient of variation lower than 5%, recoveries between 80 to 120% for a spike of 10 µg L-1 for each of the 15 compounds. The lowest limit of detection (LOD) was 38 ng L-1 for caffeine, whereas the highest value was 170 ng L-1 for ibuprofen. The method was applied to the spatial and seasonal monitoring of these compounds in the Atibaia River, which is the main drinking water source for Campinas City (São Paulo State, Brazil). Among the 15 selected emerging contaminants, 10 were detected at least once. The lowest concentration determined was 0.096 µg L-1 for diclofenac, whereas caffeine showed concentrations as high as 127 µg L-1.

A rapid and low cost method to determine Cr(VI) in soils based upon alkaline metal extraction at room temperature is proposed as a semi-quantitative procedure to be performed in the field. A color comparison with standards with contents of Cr(VI) in the range of 10 to 150 mg kg-1 was used throughout. For the different types of soils studied, more than 75% of the fortified soluble Cr(VI) were recovered for all levels of spike tested for both the proposed and standard methods. Recoveries of 83 and 99% were obtained for the proposed and the standard methods, respectively, taking into account the analysis of a heavily contaminated soil sample.

A solid-phase in-line extraction system for water samples containing low levels of emerging contaminants is described. The system was specially developed for large volume samples (up to 4 L) using commercial solid-phase extraction (SPE) cartridges. Four sets containing PTFE-made connectors, brass adapters and ball valves were used to fit SPE cartridges and sample bottles to a 4-port manifold attached to a 20 L carboy. A lab-made vacuum device was connected to the manifold cap. The apparatus is robust and less expensive than the typical available system. Its also provides less experimental handling, avoiding cross contamination and sample losses.

The increasing use of nanomaterials in several products in different areas such as electronics, cosmetics, food and drugs has attracted the attention of the scientific community due to unknown properties of these materials, such as the life cycle and the interaction with receptor organisms once they reach the environment. In this context, the present work shows an updated scenario of nanomaterials applications, characterization methods and toxicity evaluation, also addressing important aspects related to the development and application of nanotechnology under the environmental point of view.

Consumo/formação de mercúrio dissolvido gasoso (MDG) foi medido durante campanhas na Bacia do Rio Negro, Amazônia, Brasil. Foram realizadas medidas diuturnas em águas brancas e pretas. Em águas brancas, pH próximo a 7 e baixa concentração de carbono orgânico dissolvido (DOC), a saturação de MDG prevalece no período iluminado, similar a outras regiões do planeta. Esta geração de MDG foi atribuída à redução fotoinduzida do Hg2+. Por sua vez, em águas pretas, caracterizada pelo pH próximo a 5 e alto valor de DOC (até 20 mg L-1), a concentração de MDG permanece abaixo do limite de detecção no período iluminado, o que pode estar associado a oxidação fotoinduzida do Hgº. Experimentos fotoquímicos in situ corroboram a influência da radiação solar no consumo/formação do MDG. A comparação da saturação do MDG é apresentada para águas pretas e brancas.

Dissolved gaseous mercury (DGM) formation/consumption was measured during several scientific excursions in the Negro River basin, Amazon, Brazil. Measurements were carried out following diel patterns in both white and black water bodies. In white waters, with pH values around 7 and low dissolved organic carbon (DOC) concentration, mercury saturation prevails during the sunlit period, similar to behavior observed elsewhere. This was attributed to DGM generated by a photoinduced mechanism of Hg2+ reduction. On the other hand, in black waters, with pH around 5 and high DOC values (up to 20 mg L-1), DGM concentration stays below the detection limit during sunlit periods, which was associated to photoinduced Hgº oxidation. Photochemical experiments carried out in situ corroborate the influence of sunlight on DGM formation/consumption. A comparison of diel DGM saturation is presented for both black and white water bodies.

Analytical laboratories are expected to produce reliable results. Decision makers are guided in their actions (financial, legal and environmental) using analytical data provided by numerous laboratories. This work aimed to evaluate the analytical performance of Brazilian laboratories on producing trustworthy results. Nineteen laboratories, accredited and non-accredited ones, were contracted to analyze a USGS (United States Geological Survey) certified water sample for 17 chemical elements (mostly metals) without knowing the origin of the sample. Considering all the results produced, only 35% of them were valid. Three laboratories present satisfactory performances, whereas the majority showed a very poor overall performance. The outcomes of this work show the need for a more effective analytical quality program to Brazilian laboratories.

Embora com pouca atividade humana, as concentrações de Hg na bacia do Rio Negro são relativamente altas. A presença natural de Hg em solos e a deposição atmosférica são as principais fontes deste metal. O balanço entre fluxos invasivos e evasivos sugerem o seu acúmulo no interior da bacia em 39.9 t ano-1. O tipo de solo, fonte de metal para os rios, e o ciclo hidrológico com períodos de cheia e seca atuam sobre a química redox das águas. A conjunção sazonal de fatores como a natureza da matéria orgânica, pH ácido e radiação solar permitem que as águas pretas oscilem de redutora a oxidante, onde, por sua vez, ocorre o consumo de Hg0 e degradação do metilmercúrio. Deste modo, o fluxo do mercúrio pode ser invasivo ou evasivo. Embora a metilação seja mais favorecida em águas pretas, a fotodegradação do metilmercúrio se contrapõe ao seu acúmulo, contribuindo para regular o estoque deste composto na coluna água.

Despite the low level of industrial activity and human density, Hg concentration in the Negro River basin is relatively high. Soil enriched with naturally high Hg concentrations and atmospheric deposition are the main sources of the metal in this watershed. Differences between invasive and evasive fluxes at the water/air and soil/air interfaces indicate Hg accumulation in the basin at a rate of 39.9 t y-1. The type of soil, which is the main source of mercury for the water bodies, the hydrological cycle with floods and dry periods, act markedly on the water redox chemistry. A complex interaction between many seasonable variables such as solar intensity, water pH, age of the naturally occurring organic matter and the hydrological cycle alter the redox characteristics of these black water bodies, thus markedly affecting the consumption of Hg0 and the degradation of methylmercury present in the water. Although methylation is favored in black waters, photodegradation counterpoints this formation, thus regulating the methylmercury burden in the water column.

Hidrocarbonetos policíclicos aromáticos (HPA) estão presentes no óleo diesel, sendo considerados perigosos devido à sua toxicidade. Neste estudo relatamos a degradação de 16 HPA em dois solos diferentes (S1 e S2) contaminados artificialmente com óleo diesel, usando processos foto-Fenton e pseudo-foto-Fenton. Planejamentos fatoriais foram usados para obter condições de tratamento mais eficientes e econômicas. Para a reação foto-Fenton, as condições mais favoráveis resultaram 94,6% e 95,6% de degradação dos HPA para os solos S1 e S2, respectivamente. O processo pseudo-foto-Fenton também apresentou um nível satisfatório de degradação, obtido em condições econômicas, com ferro endógeno, baixa concentração de peróxido, curto tempo de exposição à radiação e sem ajuste do pH do solo. Os resultados demonstram a eficiência do processo pseudo-foto-Fenton para tratar áreas contaminadas por HPA.

Polycyclic aromatic hydrocarbon (PAH) components of diesel fuel are considered hazardous, due to their toxicity. We report the degradation of 16 PAHs using photo-Fenton and photo-Fenton-like processes in two different soil samples (S1 and S2) artificially contaminated with diesel oil. Experimental factorial designs were used to determine the most effective treatment conditions, with a view to achieving economical feasibility. For photo-Fenton reactions, the best degradation conditions resulted in an overall PAH concentration reduction of 94.6% and 95.6% for soils S1 and S2, respectively. The photo-Fenton-like processes also led to satisfactory degradation levels, obtained with only endogenous iron, low hydrogen peroxide concentration, short exposure time and no soil pH adjustment. These results demonstrate the viability of photo-Fenton-like processes to treat PAH contaminated areas.

Although the hypothesis that environmental chemicals may exhibit endocrine disrupting effects is not new, the issue has been a growing level of concern due to reports of increased incidences of endocrine-related disease in humans, including declining male fertility, and more significantly, to adverse physiological effects observed in wildlife where cause and effect relationships are more evident. The list of endocrine disrupting chemicals (EDCs) includes a range of anthropogenic compounds, phytoestrogens, naturally occurring sex steroids and synthetic estrogens. Within the aquatic environment, the presence of EDCs has concerned many scientists and water quality regulators. Discharge of effluents from treatment facilities is likely to be a significant source of input of contaminants to many systems, and the potential for concentration of hydrophilic compounds and transformation products within sludges has implications for their disposal. Then, understanding the processes and the fate of EDCs on the environment, as well as the mechanisms of endocrine disruption, may facilitate controlling or limiting exposure of both humans and the environment to these compounds.

Neste estudo foram avaliadas a capacidade de suporte e o estado de degradação do Rio Atibaia, considerando a ameaça para a vida aquática pela presença da Amônia, a qual representa um dos principais riscos às comunidades aquáticas no Rio Atibaia. Com este objetivo foi aplicado o método da Carga Máxima Total Diária (CMTD), da Agência de Proteção Ambiental dos Estados Unidos (EPA). Os resultados revelaram que as cargas de Amônia aumentavam progressivamente ao longo do Rio Atibaia, principalmente devido às fontes pontuais. As cargas de Amônia diárias assumiram valores de 30 a 5000 kg NH3. A capacidade de suporte das águas Rio Atibaia, para proteger a vida aquática contra os efeitos tóxicos da Amônia, tem sido violadas em trechos próximos à sua foz. A degradação dessas águas foi mais intensa na estação seca. Este trabalho mostrou que o esgoto doméstico não-tratado de uma população aproximada de 250 mil habitantes da cidade de Campinas, via Ribeirão Anhumas, é a principal fonte de Amônia na bacia do Rio Atibaia, apesar do grande número de indústrias ali presentes.

This study evaluated the tolerance capacity and the impairment state of the Atibaia River, considering the threat to aquatic life by the presence of Ammonia, which represents one of the main risks to the aquatic communities in the Atibaia River. With this aim, the method Total Maximum Daily Load (TMDL), from the United States Environmental Protection Agency (EPA), was applied. The results revealed that the Ammonia loads increased progressively through the Atibaia River, especially due to the point sources. The daily Ammonia loads assumed values that ranged from 30 to 5000 kg NH3. The tolerance capacity of the waters of the Atibaia River, to protect aquatic life against the toxic effects of the Ammonia, has been violated in reaches near its mouth. The impairment of these waters was more intense during the dry season. This study showed that the domestic sewer not treated of an approximate population of 250 thousand inhabitants in the city of Campinas is the main source of Ammonia in the Atibaia River Basin, despite the number of industries present there.