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Southern Brazil is an agricultural region that is experiencing strong growth in both cereal and animal production. The intensification of agricultural practices, as well as the growing urbanization in this region, also generates strong anthropogenic pressures on the aquatic environment. In Brazil, the lack of sewage treatment and the wide use of waste (liquid or solid) for the fertilization of soils are likely to favor the spread of pharmaceuticals in the surrounding environment. Considering the benefits of the determination of anthropogenic markers in the environment, the study aimed to monitor the presence of carbamazepine (CBZ) and sucralose (SCR) in the Guaporé River, representative of a southern Brazilian rural watershed. Both carbamazepine and sucralose are measured in water by polar organic chemical integrative samplers (POCIS) (CBZ: lower than limit of detection (< LOD) to 746 μg g−1 and SCR: 

Animal manure is commonly used in agriculture as fertiliser. This practice could represent, however, a risk of soil degradation through the accumulation of pharmaceutical residues or resistant microorganisms. Thus, 12 pharmaceuticals (11 antibiotics and 1 nonsteroidal anti‐inflammatory drug) were quantified in soil samples from 15 sites regularly fertilised with different animal manures (dairy cow, pig or poultry litter manure) and from forest sites in southern Brazil. This study (a) investigated the impacts of Brazilian animal waste application on antibiotic levels and induced bacterial resistance of soils and (b) determined whether one type of waste is more polluting than others. Three bacterial resistance genes, namely, sul1, qnr A, and erm, were also quantified to determine the impacts of manure application on the resistance of soil microbial communities. The effect of manure application was confirmed by the presence of antibiotic residues (up to 38.3 μg kg−1) and bacterial resistance modifications of the bacterial community (up to 8.97 × 10−3 copies of genes per bacteria) in the studied soils. Soils amended with pig manure presented the highest antibiotic concentrations. However, soils subjected to dairy cow grazing over long periods of time presented the highest concentrations of sulfonamide resistance gene (sul1). Our results lead us to infer that the type of manure can induce a “specific pollution fingerprint.”

Phosphate sorption-desorption parameters like maximum phosphorus (P) adsorption capacity (P ), equilibrium phosphorus concentration (EPC), water desorbable P (α), potentially bioavailable P (β), and mobility index (α/β ratio) were determined in order to understand the sediment source-sink nature in Guaporé catchment in southern Brazil during summer and winter 2013 and 2014. The result showed a significant (p = 0.05) variation across sediment site or seasons and revealed the most sorption-desorption parameters (P, α, β) with the increments following the order urban sediments > intensive agriculture under CT > intensive agriculture under NT > low agriculture sub-catchments (sub1 and sub2) > native forest. In the main river points, these parameters decreased along the river (P1 to P5). The results were more obvious in winter than the summer season. In contrast, the low values of λ and α/β ratio in the sediment from native forest and relatively less polluted catchment (sub1) during summer season show the quick P desorption when compared to specific Fe and Al oxides bound to stable P in intensive agriculture sediments. These findings clearly indicated that agricultural practices, sediment characteristics, and hydrological factors have a major impact on seasonal sediment P bioavailability and mobility. The urban untreated discharges may be a single major P source and, if it is not wisely managed, proves a major threat to water quality. These results have serious implications for the river ecosystem and will be of great importance to improve the environmental and economic performance of agricultural practices aiming to reduce soil-based P legacy to surface waters.

Brazil is one of the largest consumers of pesticides in the world. The high rainfall rate and inadequate soil use and management promote the transfer of these compounds to the aquatic system. The aim of this study was to identify and quantify pesticides present in epilithic biofilms in order to evaluate the effectiveness of this matrix as a bioindicator able to discriminate areas and periods with different inputs of pesticides. Among the 25 pesticides analyzed in the biofilms, 20 compounds were detected. The epilithic biofilms picked up pesticides independent of their polarities, even in the period of lower use. The frequency and median concentration of five herbicides (2,4-D, atrazine, desethyl-atrazine, simazine, nicosulfuron), three fungicides (carbendazim, epoxiconazole, tebuconazole), and one insecticide (imidacloprid) were highest in biofilms sampled in summer crops during the growing period. Biofilms collected in the upper region of the catchment, where genetically modified soybean and corn cultivated in a no-tillage system prevail, the highest frequency and median concentration of three herbicides (2,4-D, thifensulfuron, isoproturon), four fungicides (carbendazim, epoxiconazole, tebuconazole, metconazole), and one insecticide (imidacloprid) were observed. Despite the excessive amounts of pesticides used in the catchment, the median values of all pesticides in the epilithic biofilm were considered low. The lower diversity and concentration of pesticides observed in the autumn/winter season is representative of lower use of pesticides, barriers to pesticide transfer from soil to water, and the biofilm's resilience capacity to decompose pesticides.