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1.
Environ Monit Assess ; 194(9): 637, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35922699

RESUMO

Ribeirão das Pedras, a 10-km-long stream from the source to mouth, is part of a predominantly urban catchment located in Campinas metropolitan area in the state of São Paulo, Brazil, and it is also surrounded by sugarcane farms. Monthly sampling of 31 selected emerging contaminants (ECs) was conducted for 1 year (October 2018 to October 2019) in five points, including the spring, agricultural, and urban areas, to assess the dynamics and impact of ECs on the stream. The ECs were quantified using LC-MS/MS analysis. Out of the 31 ECs monitored in this study, 13 were detected in the Ribeirão das Pedras catchment, which were mainly pesticides and caffeine. Eight ECs (hexazinone, malathion, desethylatrazine (DEA), desisopropylatrazine (DIA), fipronil, ametryn, 2-hidroxyatrazine, and diuron) were detected with risk quotients higher than 1, indicating some level of environmental concern. Statistical analyses showed that caffeine, hexazinone, atrazine, DEA, and DIA were the most statistically important contaminants in temporal analysis, with caffeine concentrations varying randomly. Hexazinone, atrazine, DIA, and DEA concentrations increased from November 2018 to January 2019, and atrazine, hexazinone, and DEA concentrations increased from June 2019 to September 2019. Spatial analysis indicates that the spring of Ribeirão das Pedras is the only statistically different sampling point, with lower concentrations of EC. Points 3 and 5, both located in urban areas next to the stream's mouth, differ from each other due to the possible dilution of caffeine downstream of point 3 and domestic sewage discharge upstream of point 5.


Assuntos
Atrazina , Poluentes Químicos da Água , Atrazina/análise , Brasil , Cafeína/análise , Cromatografia Líquida , Monitoramento Ambiental , Esgotos/análise , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise
2.
Environ Monit Assess ; 194(8): 578, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35819550

RESUMO

For pesticide registrations in the USA under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), as implemented by the United States Environmental Protection Agency, drinking water risk assessments for groundwater sources are based on standard scenario modeling concentration estimates. The conceptual model for the drinking water protection goals is defined in terms of (1) a rural well in or near a relatively high pesticide use area, a shallow well (4-10 m); (2) long-term, single-station weather data; (3) soils characterized as highly leachable; (4) upper-end or surrogate, worst-case environmental fate parameters; and (5) maximum, annual use rates repeated every year. To date, monitoring data have not been quantitatively incorporated into FIFRA drinking water risk assessment; even though considerable, US national-scale temporal and spatial data for some chemistries exists. Investigations into drinking water monitoring data development have historically focused on single-source efforts that may not represent wide geographies and/or time periods, whereas Safe Drinking Water Act groundwater monitoring data are focused on a community-level scale rather than an individual, shallow, rural well. In the current case study, US national-scale, rural well data for the herbicide atrazine was collected, quality controlled, and combined into a single database from mixed sources (termed the atrazine rural well database) to (1) characterize differences between exposure estimates from standard EPA modeling approaches for specific characterization, (2) evaluate monitoring data toward direct use in US drinking water risk assessments to compliment or supersede standard modeling approaches to define risk, and (3) evaluate monitoring trends a function of time relative to label changes implemented as part of the registration review process. Of the 75,665 drinking water samples collected from groundwater, atrazine was only detected in 3185, a 4% detection rate.


Assuntos
Atrazina , Água Potável , Água Subterrânea , Praguicidas , Atrazina/análise , Monitoramento Ambiental , Praguicidas/análise , Estados Unidos
3.
Environ Pollut ; 308: 119708, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35792295

RESUMO

We apply a tracer model linked with a 3D circulation model to simulate transport and fate of water-soluble persistent substances in the Black Sea that do not bioaccumulate to a considerable extent. The model uses specified degradation time and identical concentrations in the rivers to build a correlation between average concentration in the basin and half-life (DT50). The average concentration in certain sub-regions of the Black Sea can be estimated using an exponential dependence of DT50, if DT50 and concentration in rivers are known. Averaging is performed on the simulations from 2000 to 2019 with real atmospheric forcing and river runoff. A well-defined seasonal cycle is evident for the average shelf concentration, while the average concentration in the deep region does not show a pronounced seasonal cycle or inter-annual variations. With the help of the existing observational data, we estimate DT50 and concentration in the rivers for carbamazepine, sulfamethoxazole and terbuthylazine. Atrazine and simazine are believed to have accumulated in the basin for a long time due to their widespread use in the past and the slow rate of degradation in the marine environment.


Assuntos
Atrazina , Água , Mar Negro , Monitoramento Ambiental , Rios , Simazina
4.
Environ Pollut ; 308: 119710, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35798193

RESUMO

The present study aimed to evaluate biochemical and cellular responses of the freshwater mussel, Hyriopsis bialata, to the herbicide atrazine (ATZ). The mussels were exposed to environmentally-relevant concentrations of ATZ (0, 0.02 and 0.2 mg/L) and a high concentration (2 mg/L) for 0, 7, 14, 21 and 28 days. Tissues comprising male and female gonads, digestive glands and gills were collected and assessed for ethoxyresorufin-O-deethylase (EROD) activity, glutathione S-transferase (GST) activity, multixenobiotic resistance mechanism (MXR), histopathological responses, DNA fragmentation and bioaccumulation of ATZ and its transformation derivatives, desethylatrazine (DEA) and desisopropylatrazine (DIA). Additionally, circulating estradiol levels were determined. It appeared that ATZ did not cause significant changes in activities of EROD, GST and MXR. There were no apparent ATZ-mediated histopathological effects in the tissues, with the exception of the male gonads exhibiting aberrant aggregation of germ cells in the ATZ-treated mussels. Contrarily, ATZ caused significant DNA fragmentation in all tissues of the treated animals in dose- and time-dependent manners. In general, the circulating estradiol levels were higher in the females than in the males. However, ATZ-treated animals did not show significant alterations in the hormonal levels, as compared with those of the untreated animals. Herein, we showed for the first time differentially spatiotemporal distribution patterns of bioaccumulation of ATZ, DEA and DIA, with ATZ and DEA detectable in the gonads of both sexes, DEA and DIA in the digestive glands and only DEA in the gills. The differential distribution patterns of bioaccumulation of ATZ and its derivatives among the tissues point to different pathways and tissue capacity in transforming ATZ into its transformation products. Taken together, the freshwater mussel H. bialata was resistant to ATZ likely due to their effective detoxification. However, using DNA damage as a potential biomarker, H. bialata is a promising candidate for biomonitoring aquatic toxicity.


Assuntos
Atrazina , Bivalves , Herbicidas , Unionidae , Animais , Atrazina/toxicidade , Bivalves/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Estradiol , Feminino , Água Doce , Herbicidas/metabolismo , Herbicidas/toxicidade , Masculino , Unionidae/metabolismo
5.
Sci Rep ; 12(1): 11175, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35778433

RESUMO

Across the world, paddy fields naturally harbour cyanobacteria that function as biofertilizers and secrete various compounds like Indole-3-acetic acid (IAA) that help organisms in regulating their growth. Also, paddy field farming utilizes large amounts of pesticides (e.g. atrazine); but their continued application in the agricultural field causes toxicity in non-target cyanobacterial species that hinder their performance as a biofertilizer. Hence, the current study is an attempt to ameliorate the atrazine stress in cyanobacterium Cylindrospermum stagnale by addition of IAA (1 mM each) under different atrazine levels (0, 60, 80, 100, 120, 140 µg/l). Atrazine toxicity affected C. stagnale in a dose-dependent manner further experiments revealed that both the exogenous and endogenous IAA mitigated the detrimental effects of atrazine. It reduced MDA content and simultaneously increased chlorophyll content, total protein content, and multiple antioxidant enzyme activities [superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX)] at 140 µg/l. A molecular docking study revealed that the pesticide binds to the D1 protein of the photoelectric chain in photosynthesis. Hence, the application of IAA or cyanobacterial biofertilizer that secretes a sufficient amount of IAA may assist sustainable agriculture in counteracting the atrazine toxicity.


Assuntos
Atrazina , Cianobactérias , Antioxidantes/metabolismo , Atrazina/toxicidade , Cianobactérias/metabolismo , Ácidos Indolacéticos , Simulação de Acoplamento Molecular
6.
Artigo em Inglês | MEDLINE | ID: mdl-35886730

RESUMO

The presence of pesticide residues in groundwater, many years after their phase out in European Union verifies that the persistence in aquifer is much higher than in other environmental compartments. Currently used and banned pesticides were monitored in Northern Greece aquifers and a human health risk assessment was conducted. The target compounds were the herbicides metolachlor (MET), terbuthylazine (TER), atrazine (ATR) and its metabolites deisopropylatrazine (DIA), deethylatrazine (DEA) and hydroxyatrazine (HA). Eleven sampling sites were selected to have representatives of different types of wells. Pesticides were extracted by solid-phase extraction and analyzed by liquid chromatography. MET was detected in 100% of water samples followed by ATR (96.4%), DEA and HA (88.6%), DIA (78.2%) and TER (67.5%). ATR, DIA, DEA, HA, MET and TER mean concentrations detected were 0.18, 0.29, 0.14, 0.09, 0.16 and 0.15 µg/L, respectively. Obtained results were compared with historical data from previous monitoring studies and temporal trends were assessed. Preferential flow was the major factor facilitating pesticide leaching within the month of herbicide application. Moreover, apparent age of groundwater and the reduced pesticide dissipation rates on aquifers resulted of long-term detection of legacy pesticides. Although atrazine had been banned more than 18 years ago, it was detected frequently and their concentrations in some cases were over the maximum permissible limit. Furthermore, human health risk assessment of pesticides was calculated for two different age groups though drinking water consumption. In all examined wells, the sum of the HQ values were lower than the unity. As a result, the analyzed drinking water wells are considered safe according to the acute risk assessment process. However, the presence of atrazine residues causes concerns related with chronic toxicity, since ATR R values were greater than the parametric one of 1 × 10-6 advised by USEPA, for both age groups.


Assuntos
Atrazina , Água Subterrânea , Herbicidas , Praguicidas , Poluentes Químicos da Água , Atrazina/análise , Monitoramento Ambiental/métodos , Grécia , Água Subterrânea/química , Herbicidas/análise , Humanos , Praguicidas/análise , Medição de Risco , Poluentes Químicos da Água/análise
7.
Sci Rep ; 12(1): 12570, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35869268

RESUMO

Roylea cinerea (D.Don) Baillon an indigenous medicinal plant of Lamiaceae family used for the treatment of several diseases. In the present study, its aqueous (leaves) extract was tested for genoprotective action against atrazine-induced chromosomal aberrations in the root tip cells of Allium cepa. Atrazine is a herbicide of triazine class commonly used to inhibit the growth of broad leaf and grassy weeds. In order to find the concentration of atrazine that exhibits maximum toxicity, its different concentrations (1, 5 and 10 µg/mL) were tested. It was observed that 10 µg/mL concentration was more toxic as it reduced the mitotic index and also increased the chromosomal aberrations. Among all the tested concentrations of aqueous (leaves) extracts (0.25. 0.5, 1.0, 1.5 and 3.0 µg/mL), the3.0 µg/mL concentration in both modes of experiments i.e. pre and post showed a significant reduction in chromosomal aberrations induced by atrazine. To understand the mechanism of protection by plant extract on atrazine-induced chromosomal abnormalities the RT-qPCR studies were conducted to observe the expression of marker genes Cyclin-dependent kinases (CDKs) (CDKA:1, CDKB2:1 and CDKD1:1. For this, the RNA was extracted from root tips treated with extract along with atrazine by TRIzol®. It was observed that aqueous extract of Roylea cinerea (D.Don) Baillon leaves upregulated the CDKs gene expression in both the modes i.e. pre and post treatments. A critical analysis of results indicated that aqueous extract ameliorated the chromosomal aberrations caused by atrazine which may be be due to the increased expression level of CDKs genes.


Assuntos
Atrazina , Lamiaceae , Atrazina/toxicidade , Aberrações Cromossômicas/induzido quimicamente , Quinases Ciclina-Dependentes/genética , Cebolas/genética , Folhas de Planta , Raízes de Plantas
8.
Environ Int ; 165: 107321, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35691095

RESUMO

Pesticides, which are associated with endocrine dysfunction, immunological dysregulation, and cancer, are widespread sources of drinking water contamination. The state of Paraná has a population of 11 million, is the second largest grain producer in Brazil and is a leading consumer of pesticides. In this study, we analyzed the extent of drinking water contamination from 11 proven, probable, or potentially carcinogenic pesticides (alachlor, aldrin-dieldrin, atrazine, chlordane, DDT-DDD-DDE, diuron, glyphosate-AMPA, lindane-γ-HCH, mancozeb-ETU, molinate, and trifluralin) in 127 grain-producing municipalities in the state of Paraná. Extensive contamination of drinking water was found, including legacy pesticides such as aldrin-dieldrin (mean 0.047 ppb), DDT-DDD-DDE (mean: 0.07), chlordane (mean: 0.181), and lindane-HCH (mean: 2.17). Most of the municipalities were significantly above the maximum limits for each one of the currently allowed pesticides (67% for alachlor, 9.44% for atrazine, 96.85% for diuron, 100% for glyphosate-AMPA, 80.31% for mancozeb-ETU, 91.33% for molinate, and 12.6% for trifluralin). Ninety-seven percent of municipalities presented a sum of all pesticides at levels significantly above (189.84 ppb) the European Union preconized limits (<0.5 ppb). Using the mean pesticide concentration in water (ppb), the exposed population for each municipality, and the benchmark cancer risk for pesticides, we estimated the minimum number of cancer cases attributable to pesticide-contaminated drinking water during the period (total of 542 cases). More than 80% were attributed to mancozeb-ETU and diuron. Glyphosate-AMPA and diuron-attributable cases strongly correlated with the total cancer cases in the same period (R = 0.8117 and 0.8138, respectively) as well as with breast cancer cases (R = 0.7695 and 0.7551, respectively). Water contamination was significantly correlated with the sum of the estimated cancer cases for all 11 pesticides detected in each city (R = 0.58 and p < 0.0001). These findings reveal extensive contamination of drinking water in the state of Paraná and suggest that contamination may increase the risk of cancer in this region.


Assuntos
Atrazina , Água Potável , Neoplasias , Praguicidas , Aldrina , Brasil , Clordano , DDT , Diclorodifenil Dicloroetileno , Dieldrin , Diurona , Hexaclorocicloexano/análise , Neoplasias/epidemiologia , Praguicidas/análise , Trifluralina , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico
9.
Toxicology ; 475: 153229, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35697162

RESUMO

In view of the recurrent applications of pesticides in agricultural producing countries, the increased presence of these substances in the environment raise a demand for the evaluation of adverse effects on non-target organisms. This study assesses the impact of exposure to five pesticides suspected of being endocrine disruptors (atrazine, 2,4-dichlorophenoxyacetic acid, mancozeb, chlorpyrifos and cypermethrin) on the reproductive development of the nematode Caenorhabditis elegans. To this end, nematodes in the L4 larval stage were exposed to different concentrations of pesticides for 24 h and the consequences on brood size, percentage of gravid nematodes, expression of reproductive-related genes and vitellogenin trafficking and endocytosis were measured. Moreover, 17ß-estradiol was used as an estrogenic control for endocrine disrupting compounds throughout the work. The results showed that all the pesticides disturbed to some extent one or more of the evaluated endpoints. Remarkably, we found that atrazine, 2,4-dichlorophenoxyacetic acid and chlorpyrifos produced comparable responses to 17ß-estradiol suggesting that these pesticides may have estrogen-like endocrine disrupting activity. Atrazine and 17ß-estradiol, as well as 2,4-dichlorophenoxyacetic acid and chlorpyrifos to a lesser extent, decreased the brood size, affected vitellogenin trafficking and endocytosis, and changed the expression of several reproductive-related genes. Conversely, mancozeb and cypermethrin had the least impact on the evaluated endpoint. Cypermethrin affected the brood size at the highest concentration tested and mancozeb altered the distribution of vitellogenin only in approximately 10% of the population. However, both products overexpressed hus-1 and vit-2 genes, indicating that an induction of stress could interfere with the normal development of the nematode. In conclusion, our work proved that C. elegans is a useful biological model to identify the effects of estrogen-like endocrine disruptor compounds, and the sublethal endpoints proposed may serve as an important contribution on evaluating environmental pollutants.


Assuntos
Atrazina , Clorpirifos , Disruptores Endócrinos , Herbicidas , Praguicidas , Ácido 2,4-Diclorofenoxiacético , Animais , Atrazina/toxicidade , Caenorhabditis elegans/metabolismo , Clorpirifos/toxicidade , Disruptores Endócrinos/toxicidade , Estradiol/farmacologia , Estrogênios/farmacologia , Herbicidas/toxicidade , Praguicidas/toxicidade , Vitelogeninas/genética , Vitelogeninas/metabolismo , Vitelogeninas/farmacologia
10.
Ecotoxicol Environ Saf ; 241: 113780, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35738100

RESUMO

Although listed as endocrine disruptor compounds, atrazine (ATZ) is still used in large quantities in agricultural production. Here, alfalfa seedling was cultivated in hydroponic media to investigate the toxic effects of ATZ on alfalfa and accumulation of ATZ in tissues of different plant parts. Alfalfa had a strong upward translocation ability to ATZ. The stress response of alfalfa under ATZ stress was studied using metabolomic and transcriptomic techniques. S-adenosylmethionine, glutathione, 3-mercaptopyruvic acid, ornithine, and aminopropylcadaverine were significantly increased by ATZ in pathways mtr00270 and mtr00480. Several genes of cysteine synthase and spermidine synthase were significantly up-regulated by ATZ induction. They may be markers and genes with potential physiological functions of alfalfa in response to ATZ stress. In addition, using high resolution mass spectrometry, a total of five ATZ metabolites secreted from alfalfa roots were detected. Among them, acetylated deisopropylated ATZ was discovered for the first time. Hydroxylated ATZ and acetylated deethylated ATZ were more readily excreted by the root system. This study not only provides potential genes for the construction of engineering plants to remediate ATZ-contaminated soil, but also provides monitoring objects for the ecological research of ATZ metabolites.


Assuntos
Atrazina , Disruptores Endócrinos , Herbicidas , Atrazina/metabolismo , Atrazina/toxicidade , Disruptores Endócrinos/metabolismo , Poluição Ambiental , Herbicidas/metabolismo , Medicago sativa/metabolismo
11.
Ecotoxicol Environ Saf ; 241: 113802, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35772363

RESUMO

Chemical pesticides are largely applied worldwide for the control of agricultural pests, and often cause lethal and sublethal side effects on natural enemies. To determine the compatibility of chemical pesticides, commonly used by maize growers, with Trichogramma ostriniae, the toxicities of four herbicides (pendimethalin, topramezone, glyphosate, and atrazine), three insecticides (imidacloprid, emamectin benzoate, and ethiofencarb), and three fungicides (propiconazole, benzoyl cyclazole, and difenoconazole) were tested under laboratory conditions, measuring residual toxicity to T. ostriniae adults, their lethal effects on the parasitoid's eggs inside the host egg, and on the reproduction of the parasitoid's female offspring. Three tested pesticides including ethiofencarb, glyphosate, and benzoyl cyclazole were slightly harmful to T. ostriniae adults, whereas the other seven pesticides were moderately harmful. The pesticide residues of ethiofencarb, and emamectin benzoate, showed slightly persistence of toxicity to T. ostriniae adults, in contrast to the remaining pesticides. Glyphosate, emamectin benzoate, imidacloprid, ethiofencarb, and propiconazole were classified as harmless, causing < 30% reduction in emergence rate of wasps from host eggs, while atrazine, pendimethalin, topramezone, benzoyl cyclazole, and difenoconazole were classified as slightly harmful, causing 31-52% reduction in parasitoid emergence rates. Furthermore, the number of eggs subsequently laid by T. ostriniae females that had emerged from parasitized host eggs treated with atrazine was significantly reduced compared to which of untreated parasitized host eggs. No negative effects were observed with atrazine treatment on the emergence rates of F1 wasps, their wing deformity rates and sex ratios. The data presented here indicate that the safety interval between pesticide applications and releases of T. ostriniae wasps is 2-3 weeks, which provide valuable information in designing a sound maize integrated pest management program that combines chemical pesticide applications with augmentative releases of T. ostriniae wasps.


Assuntos
Atrazina , Himenópteros , Mariposas , Praguicidas , Vespas , Animais , Feminino , Controle Biológico de Vetores , Praguicidas/toxicidade , Zea mays
12.
J Environ Manage ; 318: 115440, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35717694

RESUMO

Organic contaminants in groundwater are among the most challenging chemical compound contaminants today, particularly when it comes to understanding their occurrence, origin, and relations in groundwater, as well as the transport processes, fate, and environmental impacts involved. This paper presents the use of active carbon fibre (AFC) passive sampling and multivariate statistical processing of the results to predict the possible occurrence of organic compounds (OCs) in groundwater and to determine the origin of various anthropogenic activity. This study aims to deepen our knowledge on the control of OCs in groundwater by introducing a multi-analytical and multi-elemental holistic approach, using the Dravsko polje aquifer, the largest intergranular aquifer in Slovenia, as an example. The occurrence of OCs in groundwater was determined by means of ACFs and compared against the characteristics of the recharge area and the type of compounds detected. We combined hierarchical cluster analysis (HCA) and principal component analysis (PCA) to identify the relationship between different OCs in groundwater. The relationships between their occurrence, environmental setting and type of compound were determined using multiple linear regression (MLR). From the total of 343 organic compounds detected using passive sampling, 47 were included in further statistical analysis. MLR shows that the environmental setting is one of the most important factors affecting the different types of pollutants in groundwater. MLR models were calculated for different sources of pollution (agricultural, urban, and industrial) based on the environmental setting, land use, agglomeration, infrastructure networks, and hydrogeological characteristics of the aquifer. By means of HCA and PCA, we identified the relationships between different OCs in groundwater. As expected, the strongest correlations were found between primary compounds and their degradation products (e.g. atrazine and desethylatrazine) and compounds of similar use (e.g. atrazine and propazine, also desethylatrazine and propazine, atrazine and simazine). Some of them were also found to have a similar molecular structure (e.g. palmitic and stearic acid, 5-methoxygramine and 5-methoxytryptamine). The use of the same substances in different environments (agricultural/urban) makes them markers of both (different) origins. Therefore, it is particularly important to determine the combination of markers of different origin using multivariate statistical methods, especially in the case of mixed land use. This study identifies the main factors influencing the distribution of groundwater OCs and thus contributes to a more comprehensive understanding of the vulnerability of shallow groundwater to surface-derived contamination in similar environments.


Assuntos
Monitoramento Ambiental , Água Subterrânea , Poluentes Químicos da Água , Atrazina , Monitoramento Ambiental/métodos , Água Subterrânea/química , Análise Multivariada , Compostos Orgânicos/análise , Poluentes Químicos da Água/análise
13.
J Agric Food Chem ; 70(25): 7644-7652, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35675570

RESUMO

Poly(epsilon-caprolactone) nanoparticles are an efficient carrier system for atrazine. However, there is a gap regarding the effects of nanoencapsulation on herbicide-plant interactions. Here, we evaluate the fate and photosystem II inhibition of nano and commercial atrazine in hydroponically grown mustard (Brassica juncea) plants whose roots were exposed to the formulations. In addition, to quantify the endogenous levels of atrazine in plant organs, we measured the inhibition of photosystem II activity by both formulations. Moreover, the fluorescently labeled nanoatrazine was tracked in plant tissues using confocal microscopy. The nanoencapsulation induced greater inhibition of photosystem II activity as well as higher accumulation of atrazine in roots and leaves. The nanoparticles were quickly absorbed by the roots, being detected in the vascular tissues and the leaves. Overall, these results provide insights into the mechanisms involved in the enhanced preemergent herbicidal activity of nanoatrazine against target plants.


Assuntos
Atrazina , Herbicidas , Atrazina/farmacologia , Herbicidas/farmacologia , Mostardeira , Complexo de Proteína do Fotossistema II , Raízes de Plantas
14.
Sci Total Environ ; 838(Pt 4): 156503, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35688248

RESUMO

This manuscript described a comprehensive study on a pesticide degradation factor OsBR6ox that promoted the degradation of pesticides atrazine (ATZ) and acetochlor (ACT) in rice tissues and grains through an epigenetic mechanism. OsBR6ox was transcriptionally induced under ATZ and ACT stress. Genetic disruption of OsBR6ox increased rice sensitivity and led to more accumulation of ATZ and ACT, whereas transgenic rice overexpressing OsBR6ox lines (OEs) showed opposite effects with improved growth and lower ATZ and ACT accumulation in various tissues, including grains. OsBR6ox-mediated detoxification of ATZ and ACT was associated with the increased abundance of brassinolide (one of the brassinosteroids, BRs), a plant growth regulator for stress responses. Some Phase I-II reaction protein genes for pesticide detoxification such as genes encoding laccase, O-methyltransferase and glycosyltransferases were transcriptionally upregulated in OE lines under ATZ and ACT stress. HPLC-Q-TOF-MS/MS analysis revealed an enhanced ATZ/ATC metabolism in OE plants, which removed 1.21-1.49 fold ATZ and 1.31-1.44 fold ACT from the growth medium but accumulated only 83.1-87.1 % (shoot) and 71.7-84.1 % (root) of ATZ and 69.4-83.4 % of ACT of the wild-type. Importantly, an ATZ-responsive demethylated region in the upstream of OsBR6ox was detected. Such an epigenetic modification marker was responsible for the increased OsBR6ox expression and consequent detoxification of ATZ/ACT in rice and environment. Overall, this work uncovered a new model showing that plants utilize two mechanisms to co-regulate the detoxification and metabolism of pesticides in rice and provided a new approach for building up cleaner crops and eliminating residual pesticides in environments.


Assuntos
Atrazina , Oryza , Praguicidas , Atrazina/metabolismo , Brassinosteroides , Desmetilação do DNA , Oryza/genética , Oryza/metabolismo , Praguicidas/metabolismo , Espectrometria de Massas em Tandem
15.
J Hazard Mater ; 436: 129239, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35739758

RESUMO

Although advanced oxidation processes (AOPs) such as photoelectrochemical oxidation (PECO), electrochemical oxidation (ECO) and photocatalytic oxidation (PCO), have shown potential for wastewater treatment, their application in urban stormwater has rarely been studied. This paper explored their major degradation mechanisms and possible degradation pathways of herbicides for stormwater applications (with treatment difficulty compared with wastewater). PECO and ECO showed excellent removal performance for diuron (100 %) and moderate for atrazine (around 35 %) under a relatively low potential (2 V). Superoxide radical (·O2-) has been found to be the dominant reactive species. Besides, there is evidence to indicate that hydroxyl radical (·OH) and free chlorine (·Cl) also support the degradation reactions. Up to 11 possible intermediate products have been identified during both diuron and atrazine degradation processes under PECO operation. Based on the proposed possible degradation pathways, the intermediates presented during PECO are species with further oxidation. As evidenced by the undetected species of more oxidized intermediates for ECO and PCO, some further degradation steps are missing, which demonstrate their lower oxidation capacity leading to incomplete decomposition of stormwater herbicides. Thus, PECO has a great potential to be developed into a passive stormwater degradation system due to its strong oxidation potential.


Assuntos
Atrazina , Herbicidas , Poluentes Químicos da Água , Purificação da Água , Diurona , Herbicidas/química , Oxirredução , Poluentes Químicos da Água/química
16.
J Hazard Mater ; 436: 129243, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35739762

RESUMO

Recently, biogenic Mn oxides (BioMnOx) are considered as the promising degradation agents for environmental organic contaminants. However, little information is available for the degradation of atrazine by BioMnOx. In this work, BioMnOx, generated by a soil-derived Mn(II)-oxidizing bacterium, Providencia sp. LLDRA6, was explored to degrade atrazine. To begin with, collective results from mineral characterization analyses demonstrated that this BioMnOx was biogenic bixbyite-type Mn2O3. After that, purified biogenic Mn2O3 was found to exhibit a much higher removal efficiency for atrazine in aqueous phase, as compared to unpurified biogenic Mn2O3 and LLDRA6 biomass. During the atrazine removal by biogenic Mn2O3, six intermediate degradation products were discovered, comprising deethylatrazine (DEA), hydroxylatrazine (HA), deethylhydroxyatrazine (DEHA), ammeline, cyanuric acid, and 5-methylhexahydro-1,3,5-triazine-2-thione (MTT). Particularly, the intermediate, MTT, was considered as a new degradation product of atrazine, which was not described previously. Meanwhile, Mn(II) ions were released from biogenic Mn2O3, and on the surface of biogenic Mn2O3, the content of hydroxyl O species increased at the expense of that of lattice and water O species, but the fundamental crystalline structure of this Mn oxide remained unchanged. Additionally, no dissociative Mn(III) was found to involve in atrazine degradation. In summary, these results demonstrated that both the non-oxidative and oxidative reactions underlay the degradation of atrazine by biogenic Mn2O3.


Assuntos
Atrazina , Compostos de Manganês , Bactérias/metabolismo , Compostos de Manganês/química , Oxirredução , Óxidos/química , Providencia , Solo , Água
17.
Ecotoxicology ; 31(6): 884-896, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35585359

RESUMO

The herbicides atrazine and glyphosate are used worldwide and their excessive usage results in the frequent presence of these pesticides in environmental compartments. We evaluated the effects of environmentally relevant concentrations of analytical standards and commercial formulations of atrazine (2 µg L-1) and glyphosate (65 µg L-1), isolated and in mixture (2 + 65 µg L-1) on the microcrustacean Daphnia magna. Through chronic exposure (21 days) of two generations, we observed effects on survival, reproductive capacity and responses of the antioxidant defense system (catalase) and biotransformation system (glutathione S-transferase). The survival of organisms was affected in the second generation (F1) with a mortality of 17% in the mixture of commercial formulations treatments. In the evaluation of the first generation (F0) we observed only effects on sexual maturation of organisms, while in the F1, changes were observed in all parameters evaluated. A statistical difference (p < 0.05) was also observed between the analytical standards and the commercial formulations for all parameters evaluated, indicating that other components present in the formulations can change the toxicity of products. We suggest that atrazine can modulate toxicity when mixed with glyphosate, as the standard analytical atrazine and mixture of analytical standards results were similar in most parameters. Given the difficulty in estimating effects of mixtures and considering that various stressors are found in the environment, our results support the need to carry out long-term studies and, above all, to verify what are the impacts across generations, so that the toxicity of products is not underestimated. Graphical abstract.


Assuntos
Atrazina , Herbicidas , Poluentes Químicos da Água , Animais , Atrazina/toxicidade , Daphnia , Água Doce , Glicina/análogos & derivados , Herbicidas/toxicidade , Poluentes Químicos da Água/toxicidade
18.
Chem Res Toxicol ; 35(6): 1045-1058, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35608517

RESUMO

The population of yellow perch (Perca flavescens) in lake Saint-Pierre (QC, Canada) has been dramatically declining since 1995 without any sign of recovery. Previous studies have shown disrupted retinoid (vitamin A) metabolic pathways in these fish, possibly due to the influence of pesticides. Our study aimed to evaluate the impact of some herbicides and neonicotinoids on retinoic acid catabolism in the fish hepatic cell lines PLHC-1 and ZFL. We hypothesized that pesticides accelerate the catabolism of retinoic acid through oxidative stress that exacerbates the oxidation of retinoic acid. Results obtained with talarozole, a specific CYP26A1 inhibitor, and ketoconazole, a generalist inhibitor of cytochrome-P450 enzymes, revealed that CYP26A1 is mainly responsible for retinoic acid catabolism in ZFL but not PLHC-1 cells. The impacts of pesticides on retinoic acid catabolism were evaluated by incubating the cells with all-trans-retinoic acid and two herbicides, atrazine and glyphosate, or three neonicotinoids, clothianidin, imidacloprid, and thiamethoxam. Intracellular thiols and lipid peroxidation were measured following pesticide exposure. The possible causal relation between oxidative stress and the perturbation of retinoic acid catabolism was investigated using the antioxidant N-acetylcysteine. The data revealed that pesticides inhibit retinoic acid catabolism, with the involvement of oxidative stress in the case of atrazine, imidacloprid, and thiamethoxam but not with clothianidin and glyphosate. Pesticides also affected the isomerization of all-trans-retinoic acid over time, leading to an increased proportion of active isomers. These results hint at a possible perturbation of retinoic acid catabolism in fish living in pesticide-contaminated waters, as suggested by several in vivo studies. Such a disruption of retinoid metabolism is worrying, given the numerous physiological pathways driven by retinoids.


Assuntos
Atrazina , Herbicidas , Percas , Praguicidas , Animais , Hepatócitos/metabolismo , Herbicidas/metabolismo , Herbicidas/toxicidade , Neonicotinoides , Percas/metabolismo , Praguicidas/metabolismo , Praguicidas/toxicidade , Ácido Retinoico 4 Hidroxilase/metabolismo , Retinoides/metabolismo , Tiametoxam/metabolismo , Tretinoína/metabolismo
19.
J Hazard Mater ; 435: 128944, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35500339

RESUMO

Peroxydisulfate (PDS) is widely used in field-scale remediation of organically polluted soil, yet PDS is detrimental to the soil microbiome. In this work, sludge-derived hydrochar was used to alleviate the oxidative damage of PDS to the soil ecosystem and simultaneously improve atrazine (ATZ) degradation. Response surfaces showed that ATZ degradation was enhanced with an increased dosage of PDS (regression slope of 24.09) and hydrochar (regression slope of 4.19). In contrast, bacterial abundance was negatively related to PDS dosage but positively to hydrochar dosage. At the optimum dosage of PDS (2.21% dry weight of soil) and hydrochar (5% dry weight of soil), ATZ degradation reached 95.31%, and bacterial abundance recovered to 7.72 log gene copy number g-1 soil (versus 8.44 in raw soil). Hydrochar alleviated the negative impacts of PDS on soil fertility such as urease activity. High PDS dosages (3% dry weight of soil) facilitated the proliferation of Halomonas, while moderate dosages (1.5% dry weight of soil) stimulated Alicyclobacillus. Hydrochar facilitated the growth of functional genera like Comamonas, Cloacibacterium, and Terrabacter. ATZ degradation pathway was positively correlated with Bacillus and nitrogen metabolism pathway. Hydrochar mediated intracellular reactive oxidative species scavenger reactions in catalase activity, allowing microbial survival under harsh oxidative conditions due to PDS addition.


Assuntos
Atrazina , Microbiota , Poluentes do Solo , Atrazina/análise , Bactérias/genética , Bactérias/metabolismo , Solo , Microbiologia do Solo , Poluentes do Solo/metabolismo
20.
Chemosphere ; 301: 134754, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35490750

RESUMO

The excessive and unorganised utilisation of pesticides have posed negative impacts on soil and water at higher levels. Pesticides are a major class of persistent organic compounds with high resistance to natural biodegradation and enhanced tendency to bio accumulate. The severe health hazards imposed on the living organisms hinder the ecosystem and lead to chronic and irreversible health issues. Photocatalytic method is reported as a potential alternative with a variety of techniques and materials that are safer, easier, durable, cost-effective and efficient. Nanomaterials play a key role in this domain due to their versatility. In particular, nanostructured materials of organized shapes and morphological properties have gained enormous attention in research and real-time applications. Specifically, nanomaterials like nanotubes, nanorods and nanowires have unique properties and anisotropic structure that make them more suitable for treating pesticide wastes with photocatalysis. Variety of tuning methods and materials are emerging to enhance the activity of titanium and zinc based nanocatalysts in remediation methods. In the present article, four pesticides, namely, atrazine, chlorpyrifos, paraquat and naphthalene are chosen due to their common occurrence and usage in agricultural applications. These pesticides are highly toxic and need special attention to explore appropriate remediation methods. The report also details the latest innovations reported by several research studies in exploring the potential of specially synthesised nanoparticles for photocatalytic removal of pesticide pollutants from environment. For zinc-based hybrid nanomaterials, the maximum disintegration reported were 99%, 98%, 73.3% and 92.3% for atrazine, chlorpyrifos, paraquat and naphthalene, respectively.


Assuntos
Atrazina , Clorpirifos , Poluentes Ambientais , Praguicidas , Ecossistema , Naftalenos , Compostos Orgânicos , Paraquat , Praguicidas/química , Zinco
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