Cassiana C. Montagner

Spatial and seasonal variations of pharmaceuticals and endocrine disruptors in the Atibaia River, São Paulo State (Brazil)

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 (Sao 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.

Trace analysis of pesticides and an assessment of their occurrence in surface and drinking waters from the State of São Paulo (Brazil)

An efficient method based on solid phase extraction (SPE) and determination by liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been developed for simultaneous determination of 12 pesticides at trace levels in surface and drinking waters from the State of Sao Paulo (Brazil), which are likely to be contaminated due to the widespread use of these products. Several parameters that affect SPE and the analysis were studied, such as conditioning and elution solvents, sample pH, breakthrough volume and matrix effects. Method development was validated by several figures of merit. Recoveries from synthetic samples spiked at 150 ng L−1 and 1000 ng L−1 levels with difenoconazole, epoxiconazole, tebuconazole, atrazine, azoxystrobin, pyraclostrobin, picoxystrobin, trifloxystrobin, profenofos and fipronil varied from 73 to 99%, with intraday precision in the 5–24% range. A lower fortification level (10 ng L−1), close to detection limits, led to recoveries from 86–155%, which was considered acceptable for the purpose of trace analysis of environmental samples. Low detections limits (1–50 ng L−1) and quantification limits (2–180 ng L−1) were obtained. The method was applied for the determination of pesticide residues at the nanogram per liter level in samples of drinking water from 9 cities and in surface waters from 13 rivers of the State of Sao Paulo, Brazil. The results showed that the investigated waters are highly impacted with carbendazim and atrazine, which were the most frequently determined compounds.

Nutrients, emerging pollutants and pesticides in a tropical urban reservoir: Spatial distributions and risk assessment

Reservoirs located in urban areas suffer specific pressures related to human activities. Their monitoring, management, and protection requirements differ from reservoirs situated in non-urbanized areas. The objectives of this study were: (a) to determine the concentrations of select pesticides and emerging pollutants (EPs) present in an urban reservoir; (b) to describe their possible spatial distributions; and (c) to quantify the risks for aquatic life and safeguard drinking water supplies. For this purpose, the Guarapiranga reservoir was studied as an example of a multi-stressed urban reservoir in a tropical region. A total of 31 organic compounds (including pesticides, illicit drugs, pharmaceuticals, and endocrine disruptors) were analyzed twice over a period of one year, together with classical indicators of water quality. The physical and chemical data were treated using principal component analysis (PCA) to identify possible temporal or spatial patterns. Risk assessment was performed for biota and drinking water use, comparing maximum environmental concentrations (MECs) with the predicted no-effect concentrations (PNECs) or drinking water quality criteria (DWC), respectively. The results demonstrated the presence of pesticides and EPs, as well as pollution by high levels of nutrients and Chlorophyll a (Chl. a), during the study period. The nutrients and Trophic State Index (TSI) showed gradients in the reservoir and regional distributions, while the pesticides and EPs only clearly showed this pattern in the dry season. The concentrations and distributions of the pesticides and EPs therefore showed seasonality. These findings suggested that the two groups of pollutants (EPs+pesticides and nutrients) possessed different sources and behavior and were not always correlated in the reservoir studied. In the studied period, no risk was observed in raw water for drinking water use, but carbendazim, imidacloprid, and BPA showed risks for the biota in the reservoir.

Potential endocrine disruptor activity of drinking water samples

Conventional water treatment plants (WTP) do not completely remove contaminants with endocrine activity which may then be present in drinking water (DW). The potential for endocrine disruption of 2 DW samples collected in 2010 and 2012 from a conventional WTP in São Paulo, Brazil was investigated. In vivo assays were conducted with 21-day old female rats exposed to DW extracts for 3- (uterotrophic assay) or 20-days (pubertal assay). The exposure represented a daily ingestion of 2 L, 10 L and 20 L of DW per 60 kg-body weight. Caffeine (5.8 – 21 ug/L), estrone (1 ng/L), atrazine (2.2 – 11.2 ng/L), carbendazim (0.22 ng/L), azoxystrobin (0.23 ng/L), tebuconazole (0.19 ng/L) and imidacloprid (0.88 ng/L) were detected in DW extracts by LC-MS/MS. No increase in uterus wet weight in the uterotrophic assay, and no alteration of vaginal opening in the pubertal assay were observed. However, there were increased absolute blotted uterus weights in animals treated for 3-days with the 3 doses of both DW samples. LH and FSH levels showed significant dose-response increases in the uterotrophic assay using the 2010 DW sample, in association with a significantly increased incidence of vaginal keratinization after the 3-day exposure. The pubertal animals exposed to the 2010 DW had a significant body weight gain and decreased LH at the highest dose. Results suggest that DW samples tested exerted estrogenic and hypothalamic-hypophysis activity alterations in vivo.

Evaluation of caffeine effects on biochemical and genotoxic biomarkers in the neotropical freshwater teleost Prochilodus lineatus

Caffeine is often found in aquatic environments, leading to concerns regarding its adverse consequences for aquatic biota. Biochemical and genotoxic biomarkers were analysed in juveniles of Prochilodus lineatus to evaluate the effects of caffeine. Fish were exposed to caffeine (0.3, 3 and 30 μg L-1) for either 24 h or 168 h. Longer exposure to caffeine resulted in a significant reduction in the activity of the phase I biotransformation enzyme ethoxyresorufin-O-deethylase (EROD) in the brain but a significant increase in the liver. Changes in glutathione content (GSH), glutathione S-transferase (GST) activity, and lipid peroxidation were not found in the liver and brain of fish exposed to caffeine. DNA damage in erythrocytes were also not found. These results show that caffeine may interfere with the biotransformation mechanism of P. lineatus after 168 h exposure, but it does not generate sufficient changes to trigger a state of oxidative stress.

Emerging contaminants in Brazilian rivers: Occurrence and effects on gene expression in zebrafish (Danio rerio) embryos

Emerging contaminants (ECs) are synthetic or naturally occurring chemicals that are not commonly monitored despite having the potential of entering the environment and causing adverse ecological and/or human health effects. This study aimed to determine whether ECs are present in the surface waters of two rivers in Mato Grosso do Sul State, Brazil, and evaluate the effects of ECs mixtures at environmentally relevant concentrations on zebrafish (Danio rerio) gene expression. ECs concentrations were determined using solid-phase extraction and liquid chromatography-mass spectrometry. The ECs most frequently detected were caffeine, imidacloprid, 2-hydroxy atrazine, tebuthiuron, atrazine, and bisphenol A. We used these data to reconstruct ECs mixtures reflecting environmental concentrations, codenamed T1, T2, and T3. No effects were observed, so the concentrations were increased. After a preliminary evaluation of the No Observed Effect Concentration for each mixture, we analyzed changes in the expression of zebrafish target genes (cyp1a, hsp70, cat, sod1, tsh, cyp19a1a, cyp19a1b, cyp26b1, casp8, sox2, cyb561d2, and thrb). cat was overrepresented in T1 and underrepresented in the other treatments. All of the mixtures induced the expression of cyp19a1b, which is a marker for (xeno-)estrogen exposure, and two of them increased the expression of cyp1a, which is used to indicate the presence of dioxin-like compounds. The rivers studied had low EC concentrations, and there was no indication of any harmful effects on the zebrafish. However, intensive agricultural activity may result in unsuspected peaks of EC pollution, and subsequent negative effects on living organisms.

Eye malformation baseline in Scinax fuscovarius larvae populations that inhabit agroecosystem ponds in southern Brazil

Events of mass malformations in amphibian populations that have exceeded historical records have been reported over the past thirty years. Many of these events have been linked to human activities that occurred near amphibian breeding habitats. The rise in biofuels has promoted, and continues to promote, the growth of sugarcane plantations in Brazil, with the northwest region of Sao Paulo State having experienced the largest sugarcane expansion over the past few decades. In this region, we sampled temporary ponds located in agroecosystems dominated to different degrees by sugarcane. We found several larvae of Scinax fuscovarius with eye malformations (anophthalmia, aphakia, microphthalmia and sub-development). In this study, we assessed whether the distance from the ponds to the nearest sugarcane crop, the proportion of sugarcane surrounding the ponds, the presence of pesticides in the ponds, or the proportion of land uses with potential teratogens that surround the ponds were related to the frequencies of amphibian eye malformations. We found pesticides present in 11 of the 18 ponds, but none of the predictor variables was associated with the frequencies of amphibian eye malformations. Thus, our results suggest that the observed frequencies of amphibian eye malformations could be a consequence of natural mutation rates, and these data could be used as a malformation baseline for the region. This malformation baseline is the first reported for amphibians in South America and may be useful in future surveys on amphibian populations in tropical agroecosystems.