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1.
J Environ Qual ; 49(1): 128-139, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33016363

RESUMO

The Variable Volume Water Model (VVWM), the receiving water body model for the USEPA regulatory assessment of aquatic pesticide exposures, is composed of a set of static and quasistatic receiving water body conceptual models, but research comparing performance of these models to observations is limited. The water body models included are the constant volume (CVol), constant volume with overflow (CVO), and varying volume with overflow (VVO) models. This work quantified the performance of these three VVWM conceptual models compared with atrazine observations in 50 community water systems (CWSs), and the effect of alternative conceptual models on estimated environmental concentrations of pesticides in regulatory screening assessments. The 50 selected CWSs most relevant to the static and quasistatic VVWM concepts were small in size, with estimated time to peak flow of <1.5 d for consistency with the daily runoff assumption in USEPA landscape Pesticide Root Zone Model (PRZM). The CVO and VVO conceptual models resulted in similar distributions of bias across CWSs with the median result being close to no bias, but the CVol model resulted in overestimation in the majority of CWSs with median model bias near three times the observed values. At present, the CVol conceptual model parameterized with conservative input assumptions has been the regulatory standard invoked in VVWM, yet our results showed that a more physically correct conceptual model (CVO or VVO) could be invoked in regulatory exposure modeling for ecological risk assessment, reducing structural model bias while still allowing users to introduce conservative model inputs for screening purposes.


Assuntos
Atrazina , Praguicidas/análise , Praguicidas/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Modelos Teóricos , Água
2.
J Environ Qual ; 49(1): 152-162, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33016367

RESUMO

Pesticides are important for agriculture in the United States, and atrazine is one of the most widely used and widely detected pesticides in surface water. A better understanding of the mechanisms by which atrazine and its degradation product, deethylatrazine, increase and decrease in surface waters can help inform future decisions for water quality improvement. This study considers causal factors for trends in pesticide concentration in U.S. streams and models the causal factors, other than use, in structural equation models. The structural equation models use a concomitant trend in corn (Zea mays L.) and a latent variable model, indicating moisture supply and management. The moisture supply and management latent variable model incorporates long-term moisture conditions in the individual watersheds by using the Palmer hydrologic drought index, human influence on the hydrologic cycle through the percentage of the watershed drained by tile drains in 2012, and the base-flow contribution to streamflow, using the base-flow index. The structural equation models explain 77 and 38% of the variability in atrazine and deethylatrazine trends, respectively, across the conterminous United States. The models highlight future water quality challenges, particularly in tile-drained settings where fall precipitation and heavy precipitation are increasing.


Assuntos
Atrazina/análise , Praguicidas/análise , Poluentes Químicos da Água/análise , Agricultura , Atrazina/análogos & derivados , Estados Unidos
3.
J Environ Qual ; 49(5): 1334-1346, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33016454

RESUMO

Limited research has focused on factors affecting pesticide losses from ornamental plant production nurseries. This project evaluated the effects of overhead irrigation or simulated rainfall intensity and formulation and application methods on the losses of acephate, bifenthrin, and imidacloprid in drainage water. The liquid formulation of each respective pesticide was applied to individual replicates (potted Ilex cornuta Lindl. & Paxton plant on a drainage collection saucer) as substrate-applied drenches or foliar sprays (acephate and bifenthrin only). Granular formulations of acephate and imidacloprid were spread across the tops of media in pots. After application of treatments, irrigation or simulated rainfall was applied daily for 19 consecutive days at rates of 42.3 ± 4.57, 56.7 ± 7.92, and 95.4 ± 19.47 ml min-1 , and drainage water from individual replicates was collected for analysis. Irrigation or simulated rainfall intensity had no effects on losses of the pesticides under the conditions tested. Concentrations in drainage of all three pesticides were highest from the drench applications, whereas respective foliar spray applications resulted in the lowest active ingredient concentrations in drainage. The percentage of active ingredient lost in drainage water ranged from a minimum of 0.2 ± 0.05% (mean ± SE) for granular acephate to a maximum of 19.5 ± 3.14% (mean ± SE) for the imidacloprid drench. Most pesticide losses occurred within the first 2 d after application of drenches or sprays. Granular formulations had a longer period of release, indicating a risk of loss from overirrigation during an extended period. Results emphasize the need for careful water management after applications.


Assuntos
Praguicidas/análise , Plantas , Água
4.
Environ Monit Assess ; 192(11): 692, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33037524

RESUMO

Residue levels of seven commonly used pesticides were determined in random samples of tomatoes, French beans, and kale collected from horticultural farms in Buuri, Imenti North, and Imenti South sub-counties in Meru, Kenya, just before delivery to the consumers. QuEChERS method for extraction followed by LC-MS/MS was used to determine the concentrations. The concentrations (µg kg-1 wet weight) in French beans, kale, and tomatoes ranged from below detection limit (BDL): BDL-48.65 (carbendazim), BDL-290.76 (imidacloprid), BDL-2.81 (acetamiprid), BDL-25.76 (azoxystrobin), BDL-105.18 (metalaxyl), BDL-0.15 (diazinon), and BDL-0.17(chlorpyrifos). The maximum residue levels determined in the horticultural produce from the three regions were 290 µg kg-1 for imidacloprid in tomatoes from Buuri and 25.76 µg kg-1for azoxystrobin in French beans from Imenti South. The pesticide residue levels generally were extremely low and met the MRLs set by EU and other countries, except for carbendazim and metalaxyl in French beans, and posed no concern to human health. The estimated daily intakes (EDI) (mg kg-1 BW/day) for the population of Meru County were very low ranging from 1.685 × 10-8 (acetamiprid) to 2.381 × 10-5 (imidacloprid) in tomatoes, 2.849 × 10-9 (metalaxyl) to 3.633 × 10-7 (azoxystrobin) in French beans, and 1.392 × 10-8 (diazinon) in kale, respectively. The health risk indices were subsequently extremely low for the detectable pesticide residues, ranging from 6.74 × 10-7 (acetamiprid) to 3.97 × 10-4 (imidacloprid) in tomatoes, 3.56 × 10-8 (metalaxyl) to 5.52 × 10-5 (chlorpyrifos) in French beans, and 6.96 × 10-5 (diazinon) in kale, respectively, indicating no health risk in the population, but their presence in these vegetables cannot be ignored as long-term exposure can still cause health risks.


Assuntos
Brassica , Lycopersicon esculentum , Resíduos de Praguicidas , Praguicidas , Cromatografia Líquida , Monitoramento Ambiental , Contaminação de Alimentos/análise , Humanos , Quênia , Resíduos de Praguicidas/análise , Praguicidas/análise , Espectrometria de Massas em Tandem
5.
Environ Monit Assess ; 192(9): 615, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32876774

RESUMO

Pesticides are not only used on food but also on non-food crops, such as tobacco, to control a range of unwanted animal, plant, and microbial, fungal pests. The residue levels in tobacco leaves are expected to decline up to harvest, during drying, and when the leaves are further processed. Additional pesticides may also be applied to the finished product and residue levels may remain present even when the tobacco is burned. Human exposure to pesticide residues on tobacco occurs when residues remaining in cigarette smoke are inhaled. Based on this assumption, the objectives of this research were (i) to determine the level of pesticides residues in harvested tobacco leaves and (ii) to assess the risk of human exposure to these residues in tobacco smoke. Pesticide residues were detected in all analysed tobacco samples. These detected residues represent ten different active ingredients (AI), three of these AIs (thiodicarb, alachlor, and endosulfan) are no longer allowed in Europe. A 54.7% of these residues were quantifiable. Furthermore, it was found that with the use of solid-phase extraction sorbent (SPE) as adsorbent and n-hexane as solvent, higher recoveries of the pesticide residues in the tobacco smoke from the amount spiked can be obtained. It was also found that cigarette filters help to reduce the intake of residues of pesticides that may be present in cigarettes. Finally, the study concluded that both active smoking and passive smoking populations are exposed to pesticide residues in the tobacco smoke.


Assuntos
Resíduos de Praguicidas/análise , Praguicidas/análise , Poluição por Fumaça de Tabaco , Monitoramento Ambiental , Europa (Continente) , Humanos , Medição de Risco , Fumaça/análise , Tabaco
6.
Water Sci Technol ; 82(2): 315-329, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32941173

RESUMO

Reuse of wastewater, as well as recovery of valuable, toxic or harmful products in industrial discharges, still represents an important issue, not only because it reduces the effect on receiving water bodies, but also because of the economic resources it represents for industry itself. In this research, in situ regeneration of Mn2SO4 is evaluated, for its reuse as the main raw material in the original process of a fungicide plant. The regeneration is evaluated by selective recovery of Mn2+, Zn2+ and SO4= present in the wastewater produced by the industrial plant, and utilizing nanofiltration, electro-electrodialysis and chemical precipitation as separation alternatives. Each alternative was designed and evaluated technically and economically through simulations in Aspen Plus®, with data and information of the real process supplied by the company. Because zinc concentration is relatively low, its selective recovery was not attractive. The resulting Mn2SO4 solution and treated water quality in conventional alternatives were significantly poor with high costs. In contrast, nanofiltration and electro-electrodialysis alternatives generate water and by-products of higher quality and reuse potential with significantly lower costs. However, their viability depends on the membrane performance. The results were satisfactory, but future experimental studies are required to optimize the alternatives and define the correct pretreatment process.


Assuntos
Praguicidas , Purificação da Água , Compostos de Manganês , Sulfatos , Eliminação de Resíduos Líquidos , Águas Residuárias
7.
Anticancer Res ; 40(10): 5423-5426, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988863

RESUMO

BACKGROUND/AIM: Exposure to pesticides has been reportedly associated with several types of cancer. MATERIALS AND METHODS: In this study, we used data from The United States Geological Survey (USGS), United States Census, and the Surveillance, Epidemiology, and End Results (SEER) database to analyze the association between the area density of specific agricultural pesticides and the county level annual incidence of diffuse large B-cell lymphoma (DLBCL). RESULTS: Incidence of DLBCL was significantly associated with an area density of 14 of the pesticides reported by USGS. CONCLUSION: This highlights the need for further investigation into the safety of the use of these pesticides. The importance of this study comes not only from the significant association it shows between pesticides and the incidence of cancer, but also from the fact that it included all compounds reported to USGS as being used in agriculture. This helps in prioritizing pesticides for further evaluation.


Assuntos
Exposição Ambiental/efeitos adversos , Linfoma de Células B/epidemiologia , Linfoma Difuso de Grandes Células B/epidemiologia , Praguicidas/efeitos adversos , Humanos , Linfoma de Células B/induzido quimicamente , Linfoma de Células B/patologia , Linfoma Difuso de Grandes Células B/induzido quimicamente , Linfoma Difuso de Grandes Células B/patologia , Estados Unidos/epidemiologia
8.
Ecotoxicol Environ Saf ; 203: 111046, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888614

RESUMO

Agricultural pesticides serve as effective controls of unwanted weeds and pests. However, these same chemicals can exert toxic effects in non-target organisms. To determine chemical modes of action, the toxicity ratio (TR) and critical body residues (CBRs) of 57 pesticides were calculated for Daphnia magna. Results showed that the CBR values of inert compounds were close to a constant while the CBR values of pesticides varied over a wider range. Although herbicides are categorized as specifically-acting compounds to plants, herbicides did not exhibit excess toxicity to Daphnia magna and were categorized as inert compounds with an average logTR = 0.41, which was less than a threshold of one. Conversely, fungicides and insecticides exhibited strong potential for toxic effects to Daphnia magna with an average logTR >2. Many of these chemicals act via disruption of the nervous, respiratory, or reproductive system, with high ligand-receptor binding activity which leads to higher toxicity for Daphnia magna. Molecular docking using acetylcholinesterase revealed that fungicides and insecticides bind more easily with the biological macromolecule when compared with inert compounds. Quantitative structure-activity relationship (QSAR) analysis revealed that the toxicity of fungicides was mainly dependent upon the heat of formation and polar surface area, while the toxicity of insecticides was more related to hydrogen-bond properties. This comprehensive analysis reveals that there are specific differences in toxic mechanisms between fungicides and insecticides. These results are useful for determining relative risk associated with pesticide exposure to aquatic crustaceans, such as Daphnia magna.


Assuntos
Daphnia/efeitos dos fármacos , Modelos Biológicos , Praguicidas/química , Praguicidas/toxicidade , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase/metabolismo , Animais , Daphnia/metabolismo , Relação Dose-Resposta a Droga , Fungicidas Industriais/química , Fungicidas Industriais/toxicidade , Herbicidas/química , Herbicidas/toxicidade , Ligação de Hidrogênio , Inseticidas/química , Inseticidas/toxicidade , Simulação de Acoplamento Molecular , Resíduos de Praguicidas/metabolismo , Relação Quantitativa Estrutura-Atividade
10.
Sci Total Environ ; 740: 140152, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32927549

RESUMO

This is the first study to investigate ethylenediamine-N,N'-disuccinic acid (EDDS)/photo-Fenton process to polish real wastewater containing pesticides for possible water reuse. To this end, simultaneous degradation of pesticides ametrine, atrazine, imidacloprid and tebuthiuron was evaluated in distilled water (DW) and in sewage treatment plant (STP) effluent at initial pH 6.0. Several operational parameters (Fe3+-EDDS concentration, Fe3+-EDDS molar ratio, EDDS addition patterns and radiation source) were evaluated. 80-98% removal of target pesticides were obtained in DW using 30 µmol L-1 of Fe3+-EDDS with a molar ratio of 1:2 (300 µmol L-1 of H2O2). In addition, the proposed Fe3+-EDDS photo-Fenton at pH 6 was more efficient than classic photo-Fenton at pH 2.7 (30-84% removal). Experiments conducted in the presence of radical trapping agents (2-propanol or chloroform) revealed that HO• was the most active radical during treatment. Matrix composition strongly affected the degradation of target pesticides as a six-fold higher concentration of reagents (180 µmol L-1 of Fe3+-EDDS and 1800 µmol L-1 of H2O2) was needed to reach the same efficiency in STP compared to DW. Even so, first order rate constants corresponding to the degradation of pesticides in DW (k = 0.098-0.85 min-1) were nearly two-fold higher than in STP (k = 0.079-0.49 min-1) under the same radiation source (black-light or solar radiation). Finally, acute toxicity towards Vibrio fischeri and Drosophila melanogaster flies, and antibacterial activity assessed for Escherichia coli were eliminated after the application of the proposed treatment, thus indicating environmental safety for either discharge or reuse of treated wastewater for crop irrigation in agriculture.


Assuntos
Anti-Infecciosos , Praguicidas , Poluentes Químicos da Água/análise , Animais , Drosophila melanogaster , Peróxido de Hidrogênio , Ferro , Oxirredução
11.
Sci Total Environ ; 740: 140136, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32927574

RESUMO

Children are exposed to many potentially toxic compounds in their daily lives and are vulnerable to the harmful effects. To date, very few non-invasive methods are available to quantify children's exposure to environmental chemicals. Due to their ease of implementation, silicone wristbands have emerged as passive samplers to study personal environmental exposures and have the potential to greatly increase our knowledge of chemical exposures in vulnerable population groups. Nevertheless, there is a limited number of studies monitoring children's exposures via silicone wristbands. In this study, we implemented this sampling technique in ongoing research activities in Montevideo, Uruguay which aim to monitor chemical exposures in a cohort of elementary school children. The silicone wristbands were worn by 24 children for 7 days; they were quantitatively analyzed using gas chromatography with tandem mass spectrometry for 45 chemical pollutants, including polychlorinated biphenyls (PCBs), pesticides, polybrominated diphenyl ethers (PBDEs), organophosphorus flame retardants (OPFRs), and novel halogenated flame-retardant chemicals (NHFRs). All classes of chemicals, except NHFRs, were identified in the passive samplers. The average number of analytes detected in each wristband was 13 ±3. OPFRs were consistently the most abundant class of analytes detected. Median concentrations of ΣOPFRs, ΣPBDEs, ΣPCBs, and dichlorodiphenyltrichloroethane (DDT) and its metabolites (dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD)) were 1020, 3.00, 0.52 and 3.79 ng/g wristband, respectively. Two major findings result from this research; differences in trends of two OPFRs (TCPP and TDCPP) are observed between studies in Uruguay and the United States, and the detection of DDT, a chemical banned in several countries, suggests that children's exposure profiles in these settings may differ from other parts of the world. This was the first study to examine children's exposome in South America using silicone wristbands and clearly points to a need for further studies.


Assuntos
Poluentes Ambientais , Retardadores de Chama/análise , Praguicidas , Criança , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Humanos , Organofosfatos , Silicones , América do Sul , Uruguai
12.
Proc Biol Sci ; 287(1935): 20201390, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32993468

RESUMO

Bees and other beneficial insects experience multiple stressors within agricultural landscapes that act together to impact their health and diminish their ability to deliver the ecosystem services on which human food supplies depend. Disentangling the effects of coupled stressors is a primary challenge for understanding how to promote their populations and ensure robust pollination and other ecosystem services. We used a crossed design to quantify the individual and combined effects of food resource limitation and pesticide exposure on the survival, nesting, and reproduction of the blue orchard bee Osmia lignaria. Nesting females in large flight cages accessed wildflowers at high or low densities, treated with or without the common insecticide, imidacloprid. Pesticides and resource limitation acted additively to dramatically reduce reproduction in free-flying bees. Our results emphasize the importance of considering multiple drivers to inform population persistence, management, and risk assessment for the long-term sustainability of food production and natural ecosystems.


Assuntos
Abelhas , Inseticidas , Agricultura , Animais , Ecossistema , Feminino , Neonicotinoides , Nitrocompostos , Praguicidas , Polinização , Reprodução
13.
Sci Total Environ ; 745: 141285, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-32943215

RESUMO

During water years (WY) 2013-2017, the U.S. Geological Survey, National Water-Quality Assessment (NAWQA) Project, sampled the National Water Quality Network - Rivers and Streams (NWQN) year-round and reported on 221 pesticides at 72 sites across the United States in agricultural, developed, and mixed land use watersheds. The Pesticide Toxicity Index (PTI) was used to estimate the potential chronic and acute toxicity to three taxonomic groups - fish, cladocerans, and benthic invertebrates. For invertebrates (either cladocerans, benthic invertebrates, or both), the maximum PTI score exceeded the predicted acute toxicity screening level at 18 of the 72 sites (25%) at some point during WY 2013-2017. The predicted toxicity of a single pesticide compound was found to overwhelm the toxicity of other pesticides in the mixtures after concentrations were toxicity weighted. For this study, about 71%, 72%, and 92% of the Fish-, Cladoceran-, and Benthic Invertebrate-PTI scores, respectively, had one pesticide compound primarily contributing to sample potential toxicity (>50%). There were 17 (13 insecticides, 2 herbicides, 1 fungicide, and 1 synergist) of the 221 pesticide compounds analyzed that were the primary drivers of potential toxicity in each water sample in which the PTI and TUmax (toxic unit score for the pesticide that makes the single largest contribution to the PTI) scores were above predicted chronic (>0.1) or acute (>1) toxicity levels for one of the three taxa. For cladocerans and benthic invertebrates, the drivers of predicted chronic (>0.1) and acute (>1) PTIs were mostly insecticides. For cladocerans, the pesticide compounds driving the PTI scores were bifenthrin, carbaryl, chlorpyrifos, diazinon, dichlorvos, dicrotophos, diflubenzuron, flubendiamide, and tebupirimfos. For benthic invertebrates, atrazine (an herbicide), as well as the insecticides - bifenthrin, carbaryl, carbofuran, chlorpyrifos, diazinon, dichlorvos, fipronil, imidacloprid, and methamidophos - were the drivers of predicted toxicity. For fish, there were three pesticide types that contributed the most to predicted chronic (>0.1) PTIs - acetochlor, an herbicide; carbendazim, a fungicide degradate; and piperonylbutoxide, a synergist.


Assuntos
Praguicidas/análise , Praguicidas/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Animais , Monitoramento Ambiental , Rios , Estados Unidos , Água
14.
Med Lav ; 111(4): 296-305, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32869766

RESUMO

BACKGROUND: Occupational pesticide poisoning is an important public health concern worldwide, especially in developing countries. OBJECTIVES: This study was aimed at determining the prevalence and risk factors of acute pesticide poisoning (APP) among the vegetable and fruit farmers in Karacabey District in northwest Turkey. METHODS: The study group consisted of 565 farmers. The dependent variable of the study is APP defined according to the World Health Organization's APP case definition matrix. The study's independent variables are the farmers' sociodemographic characteristics and the preventive measures they use when they are applying pesticides. The chi-square and logistic regression analysis analyzed the relationship between the dependent and independent variables. RESULTS: A total of 64 (11.3%) farmers reported APP and 75% of them presented to a health institution due to symptoms. The factors associated with increased risk of APP were: illiteracy (odds ratio (OR)=2.5), 14 years and less farming experience (OR=3.3), not reading the pesticide labels (OR=6.4), and contact with liquid pesticides (OR=2.3). -Conclusions: The study shows that approximately one out of ten farmers experience APP. Training programs should be planned and monitored to improve farmers' awareness of the dangers of pesticides, and they should be encouraged to adopt and implement protective measures.


Assuntos
Agricultura , Exposição Ocupacional , Praguicidas , Estudos Transversais , Fazendeiros , Frutas , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Praguicidas/envenenamento , Autorrelato , Turquia , Verduras
15.
Ecotoxicol Environ Saf ; 203: 110982, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888624

RESUMO

Freshwater ecosystems are constantly threatened by the advance of agricultural activities. Abiotic variables (such as temperature, ammonia, and nitrite) and contaminants (e.g. pesticides) can potentially interact, increasing metabolism and the absorption of toxic substances, which can alter the ability of organisms to establish adequate stress responses. This study aimed to verify which pesticides were most frequently found and in the greatest quantities in low-order streams, and whether the combination of these pesticides with the abiotic variables altered the biological metabolism of aeglids. These freshwater crustaceans are important shredders that inhabit low-order streams and are sensitive to disturbances and/or abrupt environmental variations. The animals were exposed in situ in four streams (reference site and sites 1, 2, and 3). The reference site is a preserved stream with no apparent anthropogenic interference where aeglids still occur, while the other sites no longer exhibit populations of these animals and are influenced by agricultural activities. The exposure was performed bimonthly from November 2017 to September 2018 and lasted 96 h. Measured abiotic data and water samples were collected through all days of exposure. The analyzed biochemical parameters were acetylcholinesterase activity in muscle; and glutathione S-transferase, lipid peroxidation, protein carbonylation, non-protein thiols, antioxidant capacity against peroxides, and reactive oxygen species (ROS) in muscle, gills, and hepatopancreas. We found 24 active principles of pesticides, the most frequently being clomazone, atrazine, and propoxur. Bentazone was present at the highest amounts. The parameters evaluated in this study, including biochemical biomarkers and abiotic factors measured from the water, provided a separation of the months as a function of environmental conditions. There was a difference in activity and biomarker levels throughout the year within the same site and in some months between sites. The greater concentration or variety of pesticides associated with extreme abiotic (very high temperatures) data generated increased oxidative stress, with high levels of protein damage and considerable lipid damage in all tissues, as well as elevation in ROS, even with high levels of antioxidant capacity and non-protein thiols. With these data, we intend to warn about the risks of exposure to these environmental conditions by trying to contribute to the preservation of limnic fauna, especially aeglid crabs, because most species are under some degree of threat.


Assuntos
Anomuros/efeitos dos fármacos , Biomarcadores/metabolismo , Exposição Ambiental/efeitos adversos , Praguicidas/efeitos adversos , Animais , Anomuros/metabolismo
16.
Chemosphere ; 258: 127312, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947663

RESUMO

As recognized risk factor to pose a health threat to humans and wildlife globally, atmospheric particulate matter (PM) were collected from a North African coastal city (Bizerte, Tunisia) for one year, and were characterized for their chemical compositions, including mercury (HgPM), as well as organic contaminants (polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs)), organic carbon (OC) and organic nitrogen (ON), determined in a previous study. Then, we applied an in vitro reporter gene assay (DR-CALUX) to detect and quantify the dioxin-like activity of PM-associated organic contaminants. Results showed that average HgPM concentration over the entire sampling period was found to be 13.4 ± 12 pg m-3. Seasonal variation in the HgPM concentration was observed with lower values in spring and summer and higher values in winter and autumn due to the variation of meteorological conditions together with the emission sources. Principal component analysis suggested that fossil fuel combustion and a nearby cement factory were the dominant anthropogenic HgPM sources. Aryl hydrocarbon receptor (AhR)-mediated activities were observed in all organic extracts of atmospheric PM from Bizerte city (388.3-1543.6 fg m-3), and shows significant positive correlations with all PM-associated organic contaminants. A significant proportion of dioxin-like activity of PM was related to PAHs. The dioxin-like activity followed the same trend as PM-associated organic contaminants, with higher dioxin-like activity in the cold season than in the warm season, indicating the advantage and utility of the use of bioassays in risk assessment of complex environmental samples.


Assuntos
Monitoramento Ambiental , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Agricultura , Poluentes Atmosféricos/análise , Cidades , Clima , Dioxinas/análise , Humanos , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise , Receptores de Hidrocarboneto Arílico , Estações do Ano , Tunísia
17.
Chemosphere ; 258: 127333, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947666

RESUMO

Increasing use of current-use pesticides (CUPs) in Africa raises environmental and public health concerns. But there is a large uncertainty about their occurrence and the composition of pesticide mixtures on this continent. This paper investigates the presence of 27 CUPs in air across 20 sampling sites in Africa. 166 passive air samples, consisting of polyurethane foam (PUF), were collected in 12 African countries between 2010 and 2018. Samples were extracted with methanol and analyzed via high-performance liquid chromatography coupled with tandem mass spectrometry. The detection frequencies of CUPs per site were compared to land use patterns and sampling years, while their similarities were assessed using hierarchical cluster analysis. Overall, 24 CUPs were detected at least once. In 93% of all samples, at least one CUP was detected, while 78% of the samples had mixtures of two or more CUPs (median 3, interquartile range 5). Atrazine and chlorpyrifos were detected in 19 out of 20 sampling sites. Carbaryl, metazachlor, simazine, tebuconazole and terbuthylazine had the highest detection frequencies at sampling sites dominated by croplands. Across all the sampling years, 16 CUPs were present. Seven CUPs were newly detected from 2016 onwards (azinfos-methyl, dimetachlor, chlorsulfuron, chlortoluron, isoproturon, prochloraz and pyrazon), while metamitron was only present before 2012. Sites within a radius of about 200 km showed similarities in detected CUP mixtures across all samples. Our results show the presence of CUP mixtures across multiple agricultural and urban locations in Africa which requires further investigation of related environmental and human health risks.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Praguicidas/análise , África , Agricultura , Atrazina/análise , Clorpirifos/análise , Humanos , Poliuretanos
18.
Environ Monit Assess ; 192(10): 655, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32968858

RESUMO

It is known that some persistent organic pollutants (POPs) are used worldwide, and these pollutants are dangerous for human health. However, there are still countries where measurements of these pollutants have not been adequately measured. Although many studies have been published for determining the concentrations of POPs in Turkey, there are limited studies in Latin American countries like Peru. For this reason, it is essential both to conduct a study in Peru and to compare the study with another country. This study is aimed at determining the atmospheric POPs such as polycyclic aromatic hydrocarbon (PAH), organochlorine pesticide (OCP), and polychlorinated biphenyl (PCB) concentrations using passive air samplers in Yurimaguas (Peru) and Bursa (Turkey). Molecular diagnosis ratios and ring distribution methods were used to determine the sources of PAHs. According to these methods, coal and biomass combustions were among the primary sources of PAHs in Peru, while petrogenic and petroleum were the primary sources of PAHs in Turkey. Then, α-HCH/γ-HCH and ß-/(α+γ)-HCH ratios were used to determine the sources of OCPs. According to the α-HCH/γ-HCH ratios, the primary sources of OCPs in both countries were lindane. Similarly, according to ß-/(α+γ)-HCH ratios, the HCHs have been historically used in Peru while they were recently utilized in Turkey. Finally, homologous group distributions were used to determine the sources of PCBs. Similar distributions of homologous groups were observed in the sampling sites in both countries. Also, the homologous group distributions obtained have been determined that industrial activities could be effective in the sampling areas in both countries. When the cancer risks that could occur via inhalation were evaluated, no significant cancer risk has been determined in both countries.


Assuntos
Poluentes Atmosféricos/análise , Poluentes Ambientais/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Monitoramento Ambiental , Humanos , Peru , Medição de Risco , Turquia
19.
Sci Total Environ ; 740: 140015, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32927537

RESUMO

Fall armyworm (FAW) is a new invasive pest that is causing devastating effects on maize production and threatening the livelihoods of millions of poor smallholders across sub-Saharan Africa and Asia. Using unique survey data from 2356 maize-growing households in Ghana, Rwanda, Uganda, Zambia and Zimbabwe, we examined how smallholder farmers are fighting this voracious pest. In particular, we assessed the FAW management strategies used by smallholders, socio-economic factors driving the choice of the management options, the complementarities or tradeoffs among the management options, and the (un)safe pesticide use practices of farmers. Results showed that smallholder farm households have adopted a variety of cultural, physical, chemical and local options to mitigate the effects of FAW, but the use of synthetic pesticides remains the most popular option. Results from multivariate probit regressions indicated that the extensive use of synthetic pesticides is driven by household asset wealth, and access to subsidised farm inputs and extension information. We observed that farm households are using a wide range of pesticides, including highly hazardous and banned products. Unfortunately, a majority of the households do not use personal protective equipment while handling the pesticides, resulting in reports of acute pesticide-related illness. Our findings have important implications for policies and interventions aimed at promoting environmentally friendly and sustainable ways of managing invasive pests in smallholder farming systems.


Assuntos
Espécies Introduzidas , Praguicidas , Spodoptera , Agricultura , Animais , Ásia , Gana , Ruanda , Uganda , Zâmbia , Zimbábue
20.
Rev Panam Salud Publica ; 44, sept. 2020
Artigo em Inglês | PAHO-IRIS | ID: phr-52311

RESUMO

[ABSTRACT]. Antimicrobial resistance (AMR) in pathogens has been associated mainly with excessive use of antibiotics. Most studies of resistance have focused on clinical pathogens; however, microorganisms are exposed to numerous anthropogenic substances. Few studies have sought to determine the effects of chemical substances on microorganisms. Exposure to these substances may contribute to increased rates of AMR. Understanding microorganism communities in natural environments and AMR mechanisms under the effects of anthropogenic substances, such as pesticides, is important to addressing the current crisis of antimicrobial resistance. This report draws attention to molecules, rather than antibiotics, that are commonly used in agrochemicals and may be involved in developing AMR in non-clinical environments, such as soil. This report examines pesticides as mediators for the appearance of AMR, and as a route for antibiotic resistance genes and antimicrobial resistant bacteria to the anthropic environment. Available evidence suggests that the natural environment may be a key dissemination route for antibiotic-resistant genes. Understanding the interrelationship of soil, water, and pesticides is fundamental to raising awareness of the need for environmental monitoring programs and overcoming the current crisis of AMR.


[RESUMEN]. La resistencia a los antimicrobianos (RAM) en los agentes patógenos ha sido relacionada principalmente con el uso excesivo de los antibióticos. La mayoría de los estudios sobre la resistencia se han centrado en los agentes patógenos de importancia clínica; sin embargo, los microorganismos están expuestos a numerosas sustancias antropogénicas. Son muy pocos los estudios dedicados a determinar los efectos que producen las sustancias químicas en los microorganismos. La exposición a estas sustancias puede contribuir a los niveles mayores de la RAM. Comprender las comunidades de microorganismos en el medioambiente natural y los mecanismos de la RAM por los efectos de las sustancias antropogénicas, como los plaguicidas, resulta importante para abordar la actual crisis de la resistencia a los antimicrobianos. En este informe se hace énfasis en las moléculas, en lugar de los antibióticos, que se usan generalmente en los productos agroquímicos y que podrían contribuir a que se desarrolle la RAM en entornos no clínicos, como el suelo. Asimismo, se analiza el papel de los plaguicidas como mediadores en la aparición de la RAM, así como la manera en la que los genes y los microorganismos resistentes a los antibióticos se trasladan hacia el entorno antrópico. La evidencia indica que el entorno natural podría ser una vía clave de propagación para los genes resistentes a los antibióticos. Comprender la interrelación entre el suelo, el agua y los plaguicidas es fundamental para crear consciencia en cuanto a la necesidad de establecer programas de seguimiento ambiental y así poder superar la crisis actual de la RAM.


[RESUMO]. A resistência antimicrobiana dos patógenos está principalmente associada ao uso excessivo de antibióticos. Os estudos sobre resistência se concentram, na sua maioria, nos patógenos de importância clínica. Porém, os microrganismos são expostos a inúmeras substâncias antropogênicas e existem poucos estudos sobre os efeitos que os compostos químicos causam nos microrganismos. A exposição a estes compostos pode contribuir para o aumento da resistência antimicrobiana. Entender as comunidades de microrganismos em ambiente natural e os mecanismos de resistência antimicrobiana por ação das substâncias antropogênicas, como os pesticidas, é essencial no combate à atual crise de resistência antimicrobiana. Este informe destaca os compostos ativos (exceto antibióticos) normalmente usados nos produtos agroquímicos que podem contribuir para o surgimento de resistência antimicrobiana em ambientes não clínicos, como o solo. Examina-se o papel dos pesticidas como mediadores da resistência antimicrobiana e as vias pelas quais os genes que conferem resistência e as bactérias resistentes aos antimicrobianos alcançam o ambiente antrópico. As evidências indicam que o ambiente natural pode ser uma das principais vias de disseminação dos genes que conferem resistência aos antibióticos. Entender a inter-relação entre solo, água e pesticidas é fundamental para conscientizar sobre a necessidade de programas de monitoramento ambiental e combater a atual crise de resistência antimicrobiana.


Assuntos
Resistência Microbiana a Medicamentos , Praguicidas , Resistência Microbiana a Medicamentos , Praguicidas , Resistência Microbiana a Medicamentos , Praguicidas
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