PURPOSE: Many reports on purification of water containing pesticides are based on studies using unformulated active ingredients. However, most commercial formulations contain additives/adjuvants or are manufactured using microencapsulation which may influence the purification process. Therefore, the main objective of this work was to develop and test a pilot scheme for decontaminating water containing pesticides formulated with antifoaming/defoaming agents. METHODS: The Freundlich adsorption coefficients of formulation of cyprodinil, a new-generation fungicide, onto the organoclay Cloisite 20A have been determined in the laboratory in order to predict the efficiency of this organoclay in removing the fungicide from waste spray-tank water. Subsequently, the adsorption tests were repeated in the pilot system in order to test the practical operation of the purification scheme. RESULTS: The laboratory adsorption tests successfully predicted the efficiency of the pilot purification system, which removed more than 96% cyprodinil over a few hours. The passing of the organoclay–cyprodinil suspension through a layer of biomass gave 100% recovery of the organoclay at the surface of the biomass after 1 week. The organoclay was composted after the treatment to try to break down the fungicide so as to allow safe disposal of the waste, but cyprodinil was not significantly dissipated after 90 days. CONCLUSION: The purification scheme proved to be efficient for decontaminating water containing cyprodinil formulated with antifoaming/defoaming agents, but additional treatments for the adsorbed residues still appear to be necessary even for a moderately persistent pesticide such as cyprodinil. Furthermore, a significant conclusion of this study concerns the high influence of pesticide formulations on the process of purification of water containing these compounds, which should be taken into account when developing innovative decontamination schemes, especially for practical applications.

PURPOSE: To assess groundwater exposure to pesticides, in agricultural areas of ‘Ribatejo’ region (Portugal), and the influence of some key factors in that exposure, field, laboratory and modelling studies were carried out. METHODS: The study was performed in maize, potato, sugar beet, tomato and vegetables agricultural areas, located in a shallow aquifer, with pesticides use and, in most cases, with irrigation practices. Pesticides used in the studied agricultural areas and having leaching potential were selected, being considered also other pesticides included in priority lists, defined in Europe. Evaluation of groundwater exposure to pesticides was carried out by successively: (1) groundwater sampling in seven campaigns over the period 2004–2006; (2) pesticide analysis [including isolation and concentration from the groundwater samples and further determination by gas chromatography–mass spectrometry (GC–MS) of 14 herbicides, four insecticides and two metabolites]; and (3) analysis and discussion of the results by applying joint correspondence analysis (JCA). RESULTS: From the 20 pesticides and metabolites selected for the study, 11 were found in groundwater. Pesticides and metabolites most frequently detected were atrazine, alachlor, metolachlor, desethylatrazine, ethofumesate, α-endosulfan, metribuzine, lindane and β-endosulfan. The results showed that groundwater exposure to pesticides is influenced by local factors—either environmental or agricultural, as precipitation, soil, geology, crops and irrigation practices. Spring and autumn were more associated with the detection of pesticides being more likely to observe mixtures of these compounds in a groundwater sample in these transition seasons. CONCLUSIONS: This work evidences the importance of models, which evaluate pesticides environmental behaviour, namely their water contamination potential (as Mackay multicompartimental fugacity model) and, specially, groundwater contamination potential (as GUS and Bacci and Gaggi leaching indices), in pesticide selection. Moreover, it reveals the importance to adapt proper statistical methods according to level of left-censored data. Using JCA was still possible to establish relations between pesticides and their temporal trend in a case study where there were more than 80% of data censored. This study will contribute to the Tagus river basin management plan with information on the patterns of pesticide occurrence in the alluvial aquifer system.

PURPOSE: In this study, we investigated the effects of maternal transfer of bisphenol A (BPA) and di(2-ethylhexyl) phthalate (DEHP) during gestational and weaning periods on gonadal development of male offspring. METHODS: Pregnant CD-1 mice were administered by gavages in corn oil with 0.1, 1, or 10 mg/kg/day of BPA and DEHP from gestational days (GD1–21) to the weaning period (postnatal days (PND) 1–21). RESULTS: Our data indicated that the exposure significantly reduced the male-to-female sex ratio and the sizes of the gonads of male pups as recorded at PND15. The testes of the perinatally exposed male pups were developed less and the expression levels of testicular anti-mullerian hormone, androgen receptor, cyclin A, and StAR were significantly lesser than the control male pups. The less developed testes were accompanied with significant reductions in the expression levels of Gnrh and Fsh at the hypothalamic–pituitary levels. The negative effects were found to be persistent in the sexually mature pups at PND42. CONCLUSION: Our data reveal that the maternal transfer of BPA and DEHP may impose negative influence on the development and functions of the reproductive system of male pups.

CO₂ leakages during carbon capture and storage in sub-seabed geological structures could produce potential impacts on the marine environment. To study lethal effects on marine organisms attributable to CO₂ seawater acidification, a bubbling CO₂ system was designed enabling a battery of different tests to be conducted, under laboratory conditions, employing various pH treatments (8.0, 7.5, 7.0, 6.5, 6.0, and 5.5). Assays were performed of three exposure routes (seawater, whole sediment, and sediment elutriate). Individuals of the clam (Ruditapes philippinarum) and early-life stages of the gilthead seabream, Sparus aurata, were exposed for 10 days and 72 h, respectively, to acidified clean seawater. S. aurata larvae were also exposed to acidified elutriate samples, and polychaete organisms of the specie Hediste diversicolor and clams R. philippinarum were also exposed for 10 days to estuarine whole sediment. In the fish larvae elutriate test, 100 % mortality was recorded at pH 6.0, after 48 h of exposure. Similar results were obtained in the clam sediment exposure test. In the other organisms, significant mortality (p < 0.05) was observed at pH values lower than 6.0. Very high lethal effects (calculating L[H⁺]50, defined as the H⁺ concentration that causes lethal effects in 50 % of the population exposed) were detected in association with the lowest pH treatment for all the species. The implication of these results is that a severe decrease of seawater pH would cause high mortality in marine organisms of several different kinds and life stages. The study addresses the potential risks incurred due to CO₂ leakages in marine environments.

INTRODUCTION: The photocatalytic degradation of Orange G (OG) dye has been investigated using synthesised nanocrystalline ZnO as a photocatalyst and sunlight as the irradiation source. The formation of ZnO prepared from its precursor was confirmed through FT-IR and powder X-ray diffraction analyses. MATERIALS AND METHODS: Surface morphology was characterised by scanning electron microscope and transmission electron microscope analysis. Band gap energy of synthesised nanocrystalline ZnO was calculated using diffuse reflectance spectroscopy (DRS). Different experimental parameters such as effects of pH, dye concentrations and mass of catalyst were standardised in order to achieve complete degradation of the dye molecules under solar light irradiation. RESULTS: The kinetics of oxidation of OG was also studied. The complete degradation of OG was evident after 90 min of irradiation at an initial pH of 6.86. The degradation of OG was confirmed by UV–Visible spectrophotometer, high-pressure liquid chromatography, ESI-Mass and chemical oxygen demand analyses. CONCLUSION: The adsorption of dye onto catalytic surface was analysed employing model equations such as Langmuir and Freundlich isotherms, and it was found that the Langmuir isotherm model best fitted the adsorption data. The solar photodegradation of OG followed pseudo-first-order kinetics. HPLC and ESI-Mass analyses of the degraded samples suggested that the dye molecules were readily degraded under solar irradiation with nanocrystalline ZnO.

INTRODUCTION: Levoglucosan and carbonaceous species in the background aerosol of coastal southeast China were measured at Jianfengling (JFL), a background mountain site in a National Reserve Park on Hainan Island, and at Hok Tsui (HT), a rural site on the southern coast of Hong Kong from April to May of 2004 during an intensive field study. METHODS: We integrated the information from field study, satellite and backward trajectory model to examine the long-range transport of biomass burning smoke from the Philippines and assess its impact on background aerosol in coastal southeast China. RESULTS AND DISCUSSION: The average levoglucosan concentrations were 42 and 30 ng m−3 at JFL and HT, respectively, while the organic and elemental carbon concentrations were 3.1 and 0.4 μg C m−3 respectively at JFL, and 4.1 and 1.3 μg C m−3 respectively at HT. Elevated levoglucosan concentrations of 85–106 ng m−3 (250–340% extra loadings) at JFL and 57 ng m−3 (170% extra loading) at HT were observed during transport events in which air masses originated from the Philippines. Fire hot spot counts and aerosol index derived from satellite data showed that the spread of biomass burning smoke from the Philippines resulted in large-scale dense aerosol clouds in the adjacent South China Sea and the western Pacific Ocean. The observed high ratio of two biomass-burning tracers (levoglucosan to mannosan) at JFL (7–36) and HT (27) indicated that the biomass smoke originating from the Philippines had significant contributions from open-field burning of agricultural residues, such as rice straw. The pollution plumes were transported to southeast China resulting in elevated concentrations of carbonaceous aerosol and levoglucosan in particular. Using a simplified receptor-based approach, biomass smoke aerosol was estimated to account for 16–28% of OC in the background atmosphere of Hainan and 4.9% of OC at the rural site of Hong Kong during these episode cases, indicating that biomass burning smoke generated in the Philippines could have a significant contribution to background ambient aerosol of southeast coastal China.

PURPOSE: The two artificial sweeteners cyclamate (CYC) and acesulfame (ACE) have been detected in wastewater and drinking water treatment plants. As in both facilities ozonation might be applied, it is important to find out if undesired oxidation products (OPs) are formed. METHODS: For the separation and detection of the OPs, several analytical techniques, including nuclear magnetic resonance experiments, were applied. In order to distinguish between direct ozone reaction and a radical mechanism, experiments were carried out at different pH values with and without scavenging OH radicals. Kinetic experiments were used for confirmation that the OPs are formed during short ozone contact time applied in waterworks. Samples from a waterworks using bank filtrate as raw water were analyzed in order to prove that the identified OPs are formed in real and full-scale ozone applications. RESULTS: In the case of CYC, oxidation mainly occurs at the carbon atom, where the sulfonamide moiety is bound to the cyclohexyl ring. Consequently, amidosulfonic acid and cyclohexanone are formed as main OPs of CYC. When ozone reacts at another carbon atom of the ring a keto moiety is introduced into the CYC molecule. Acetic acid and the product ACE OP170, an anionic compound with m/z=170 and an aldehyde hydrate moiety, were identified as the main OPs for ACE. The observed reaction products suggest an ozone reaction according to the Criegee mechanism due to the presence of a C=C double bond. ACE OP170 was also detected after the ozonation unit of a full-scale drinking water treatment plant which uses surface water-influenced bank filtrate as raw water. CONCLUSIONS: Acesulfame can be expected to be found in anthropogenic-influenced raw water used for drinking water production. However, when ACE OP170 is formed during ozonation, it is not expected to cause any problem for drinking water suppliers, because the primary findings suggest its removal in subsequent treatment steps, such as activated carbon filters.

Cyanobacterial blooms represent a serious threat to the aquatic environment. Among other effects, biochemical markers have been studied in aquatic vertebrates after exposures to toxic cyanobacteria. Some parameters such as protein phosphatases may serve as selective markers of exposure to microcystins, but under natural conditions, fish are exposed to complex mixtures, which affect the overall biomarker response. This review aims to provide a critical summary of biomarker responses in aquatic vertebrates (mostly fish) to toxic cyanobacteria with a special focus on detoxification and oxidative stress. Detoxification biomarkers such as glutathione (GSH) and glutathione-S-transferase (GST) showed very high variability with poor general trends. Often, stimulations and/or inhibitions and/or no effects at GSH or GST have been reported, even within a single study, depending on many variables, including time, dose, tissue, species, etc. Most of the oxidative stress biomarkers (e.g., superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase) provided more consistent responses, but only lipid peroxidation (LPO) seemed to fulfill the criteria needed for biomarkers, i.e., a sufficiently long half-life and systematic response. Indeed, reviewed papers demonstrated that toxic cyanobacteria systematically elevate levels of LPO, which indicates the important role of oxidative damage in cyanobacterial toxicity. In summary, the measurement of biochemical changes under laboratory conditions may provide information on the mode of toxic action. However, comparison of different studies is very difficult, and the practical use of detoxification or oxidative stress biomarkers as diagnostic tools or early warnings of cyanobacterial toxicity is questionable.

INTRODUCTION: Flowing of the acid mine drainage may contaminate the adjacent water bodies causing substantial changes in the aquatic ecosystem. This aspect is the most relevant problem in the southern of Santa Catarina once the contaminated areas are inserted in the watershed of the Araranguá, Urussanga, and Tubarão rivers, increasing the need for recovery studies. These areas are between Criciúma, Içara, Urussanga, Siderópolis, Lauro Müller, Orleans, and Alfredo Wagner towns where a conservation unit exist called the Environmental Preservation Area of Baleia Franca. Aiming to compare the kinetics of the ash derived from burning coal and to neutralize acid mine drainage, different neutralizer, limestone, fly, and bottom ash, was mounted on a pilot scale experiment. DISCUSSION: The transport parameters showed the same order of infiltration and dispersion: fly ash < bottom ash < limestone. The order of measured alkalinity was: limestone < fly ash < bottom ash, with pH values of 9.34, 12.07, and 12.25, respectively. The limestone kinetics of acidic drainage neutralization was first order with reaction rate constant k = 0.0963 min−1, bottom ash was 3/4 with k = 0.0723 mol1/4 L−1/4 min−1, and the fly ash had higher order kinetics, 4/3, with reaction rate constant k = 27.122 L1/3 mol−1/3 min−1. However, by mathematical modeling, it was found that due to a combination of transport and kinetics, only limestone treatment reached a pH above 6 within 5 years, corresponding to the ideal as planned.

INTRODUCTION: In this study, UV/Oxone/Co2+ oxidation process was applied to degradation of ofloxacin (OFL) in the presence of Co2+ as the catalytic and Oxone as the oxidant. The operation parameters including pH, temperature, dosages of reagents, and reaction time were studied in detail. RESULTS: The results showed that the optimum conditions for the UV/Oxone/Co2+ processes were determined as follows: temperature = 25°C, pH = 5.0, [Oxone] = 0.6 mmol/L, [Oxone]/[Co2+] = 1,000, and reaction time = 60 min. Under these conditions, 100% of the OFL degraded. The kinetics was also studied, and degradation of OFL by the UV/Oxone/Co2+ process could be described by first-order kinetics. CONCLUSIONS: Mineralization of the process was investigated by measuring the total organic carbon (TOC), and the TOC decreased by 87.0% after 60 min. This process could be used as a pretreatment method for wastewater containing ofloxacin.