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991.
Sorption of acetamiprid ((E)-N1-[(6-chloro-3-pyridyl)methyl]-N2-cyano-N1-methylacetamidine), carbendazim (methyl benzimidazol-2-ylcarbamate), diuron (N-(3,4-dichlorophenyl)-N, N-dimethyl urea) and thiamethoxam (3-(2-chloro-thiazol-5-ylmethyl)-5-methyl-[1,3,5]oxadiazinan-4-ylidene-N-nitroamine) was evaluated in two Brazilian tropical soils, Oxisol and Entisol, from Primavera do Leste region, Mato Grosso State, Brazil. To describe the sorption process, batch experiments were carried out. Linear and Freundlich isotherm models were used to calculate the K(d) and K(f) coefficients from experimental data. The K(d) values were utilized to calculate the partition coefficient normalized to soil organic carbon (K(oc)). For the pesticides acetamiprid, carbendazim, diuron and thiamenthoxan the K(oc) (mL g(- 1)) values ranged in both soils from 98 - 3235, 1024 - 2644, 145 - 2631 and 104 - 2877, respectively. From the studied pesticides, only carbendazim presented correlation (r(2) = 0.82 and p < 0.01) with soil organic carbon (OC) content. Acetamiprid and thiamethoxam showed low sorption coefficients, representing a high risk of surface and ground water contamination.  相似文献   
992.
Environmental Science and Pollution Research - Aquaculture is an activity with economic and social importance since it generates food, employment, and income. However, like other human activities,...  相似文献   
993.
The reintroduction of a species that is extinct in the wild demands caution because reintroduction locations may be associated with threats, such as hunting, poor-quality habitat, and climate change. This is the case for Cyanopsitta spixii (Spix's Macaw), which has been extinct in the wild since 2000. The few living individuals were created in captivity and will be used in a reintroduction project within the species’ original distribution area, the Caatinga domain (Brazil). Because the occurrence records for this bird are old and inaccurate, we investigated the current and future environmental suitability of the 14 plant species used by C. spixii as resource. These plants are key elements for the long-term reestablishment of the species in the wild, so the use of models helps in the assessment of the effects of climate change on the availability of these resources for the species and informs selection of the best places for reintroduction. We based our models of environmental suitability on 19 bioclimatic variables and nine physical soil and topography variables. Climate projections were created for the present and for the year 2070 with an optimistic (SSP2-4.5) and a pessimistic (SSP5-8.5) climate scenario. Both future climate scenarios lead to a reduction in area of environmental suitability that overlapped for all the plant species: 33% reduction for SSP2-4.5 and 63% reduction for SSP5-8.5. If our projections materialize, climate change could thus affect the distribution of key resources, and the maintenance of C. spixii would depend on restoration of degraded areas, especially riparian forests, and the preservation of already existing natural areas. The Caatinga domain is very threatened by habitat loss and, for the success of this reintroduction project, the parties involved must act to protect the species and the resources it uses.  相似文献   
994.
Objective: Truck drivers represent a group that is susceptible to the use of stimulant substances to reduce the symptoms of fatigue, which may be caused by a stressful and exhausting work environment. The use of psychoactive substances may increase the risk for involvement in road traffic crashes. Previous studies have demonstrated that amphetamine, cocaine, and cannabis are the 3 main drugs used by Brazilian truck drivers. We studied the prevalence of amphetamine, benzoylecgonine (indicating use of cocaine), and Δ-9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH; indicating use of cannabis) in urine samples from truck drivers in the state of São Paulo, Brazil, using the same methodology during 8 years (2009–2016).

Methods: Samples were collected during a health program supported by the Federal Highway Police. Toxicological analyses were performed using immunoassays and gas chromatography–mass spectrometry.

Results: The total prevalence of illicit drugs was 7.8%. Benzoylecgonine was the most prevalent substance (3.6%), followed by amphetamine (3.4%) and THC-COOH (1.6%). We found the highest drug prevalence in 2010 (11.3%) and the lowest in 2011 (6.1%). We could detect a slight change in the pattern of stimulant use: until 2010, amphetamine was the most prevalent substance; however, in 2011 benzoylecgonine became the most frequently detected substance. This lasted until 2015, probably due to changes in Brazilian legislation regarding appetite suppressants; the most common one is metabolized to amphetamine.

Conclusion: These data show that the use of psychoactive substances by truck drivers in Brazil did not decrease during the study period. This reinforces the need for further preventive measures to reduce drug use among drivers, which could lead to a decrease in traffic crashes in Brazil.  相似文献   

995.
Birds of prey, owls and falcons are widely used as sentinel species in raptor biomonitoring programmes. A major current challenge is to facilitate large-scale biomonitoring by coordinating contaminant monitoring activities and by building capacity across countries. This requires sharing, dissemination and adoption of best practices addressed by the Networking Programme Research and Monitoring for and with Raptors in Europe (EURAPMON) and now being advanced by the ongoing international COST Action European Raptor Biomonitoring Facility. The present perspective introduces a schematic sampling protocol for contaminant monitoring in raptors. We provide guidance on sample collection with a view to increasing sampling capacity across countries, ensuring appropriate quality of samples and facilitating harmonization of procedures to maximize the reliability, comparability and interoperability of data. The here presented protocol can be used by professionals and volunteers as a standard guide to ensure harmonised sampling methods for contaminant monitoring in raptors.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01341-9) contains supplementary material, which is available to authorized users.  相似文献   
996.
Environmental Science and Pollution Research - This study aimed to use bioassays (single and multispecies) with organisms from different trophic levels to assess soil quality in reclaimed coal...  相似文献   
997.
Environment, Development and Sustainability - Soils feature significant variations in soil carbon stocks through land-use changes, management practices, and intrinsic characteristics. The aim of...  相似文献   
998.
Environmental Geochemistry and Health - Mercury is widely found in nature, however, in low concentrations, but anthropological activities have increased its concentration considerably. This causes...  相似文献   
999.
Environmental Science and Pollution Research - Metal contamination is a threat to estuarine environments. They can accumulate in the food chain and cause toxic effects on aquatic organisms and...  相似文献   
1000.
Journal of Material Cycles and Waste Management - Predicting municipal solid waste (MSW) generation is fundamental in choosing and scaling the processes involved in municipal management. The...  相似文献   
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