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1.
Artigo em Inglês | MEDLINE | ID: mdl-33810013

RESUMO

Extensive use of herbicides is common among rural agricultural workers in Sri Lanka. Recent studies have postulated their role in the development of chronic kidney disease of unknown etiology (CKDu). Paraquat and glyphosate are leading herbicides used by sugarcane farmers (SF), hence occupational exposure is inevitable. This study examined the expression of urinary paraquat, glyphosate and biomarkers among residential SF in CKDu emerging regions, Warunagama (WA) and Rahathangama (RH), in the Uva Province with non-endemic Matara (MA) in the Southern Province of Sri Lanka. Urinary glyphosate, Paraquat, kidney injury molecule -1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL) and ß2-microglobulin (B2M) were determined using enzyme-linked immunosorbent assays (ELISA). Urinary creatinine, microalbumin, serum creatinine (SCr), serum cystatin C, estimated glomerular filtration rate (eGFR), and albumin creatinine ratio (ACR) were also assessed. Generally, herbicide residues and kidney injury biomarkers were higher in SF compared to the non-endemic MA. Creatinine-adjusted urinary glyphosate and paraquat levels were significantly higher in WA compared to MA. ACR in RH (median 14.9; IQR 5.4-393.1 mg/g) and WA (23.7; 11.5-64.6) was significantly higher than MA (4.3; 2.2-6.7). This study reports 39 individuals with impaired kidney function among SF in Sri Lanka for the first time. Urinary NGAL levels were significantly higher in both WA (median 2.14; IQR 1.28-6.15 ng/mg Cr) and RH (3.09; 1.15-9.09) compared to MA (1.28; 0.56-2.81). However, urinary KIM-1 levels in RH (3.2; 1.29-106.1 ng/g Cr) and WA (3.6; 1.94-115.1) were not significantly higher in MA (1.74; 0.76-116.9). Urinary NGAL (r = 0.493), eGFR (r = -0.147) and ACR (r = 0.171) significantly correlated with urinary glyphosate, but not with urinary paraquat levels. Urinary KIM-1 levels did not correlate with either urinary glyphosate or paraquat, while urinary B2M and serum cystatin C levels showed significant correlation with urinary glyphosate levels. The current study reports higher urinary herbicide levels among sugarcane farmers in WA and RH, and that is potentially linked to the subsequent decline in kidney function, as indicated by ACR, eGFR, and NGAL. We posit that these indicators may serve as markers to detect renal injury among herbicide-exposed SF in Rural Sri Lanka.


Assuntos
Glicina , Paraquat , Agricultura , Biomarcadores , Creatinina , Glicina/análogos & derivados , Glicina/toxicidade , Humanos , Paraquat/toxicidade , Sri Lanka
2.
Ecotoxicology ; 30(3): 492-501, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33649983

RESUMO

We assessed the short-term viability and recovery of zooplankton communities after exposure to glyphosate (active ingredient-a.i.). We conducted a hatching experiment in two steps: Step 1-natural lake sediments containing resting egg banks were placed into individual trays and exposed to a solution medium of glyphosate at three different treatments (LD = Values below the detection limits, LD < 0.05, 0.44, and 0.89 mg a.i./L) for 14 days; and Step 2-we replaced the exposure solution of glyphosate with distilled freshwater, keeping them all trays under freshwater conditions for another 14 day. The results from Step 1 showed significant effects of glyphosate on the emergence patterns of resting eggs, with a reduction in hatching of rotifers, mainly at concentrations of 0.44 and 0.89 mg a.i./L. On the other hand, the results from Step 2 showed an increase in the emergence of viable eggs for rotifers after restoration of freshwater conditions in all treatments; there was no effect for total zooplankton and microcrustaceans. These findings suggest that (i) glyphosate may, effectively, impair zooplankton hatching from resting egg banks; (ii) the magnitude of the negative effects depends on the the zooplanktonic group considered; and (iii) the restoration of freshwater conditions may, in some way, allow the recovery of the zooplankton community from viable egg banks. Our results can be useful in predicting the influence of glyphosate on the distribution patterns of freshwater zooplankton, which can represent vital information for environmental managers.


Assuntos
Rotíferos , Zooplâncton , Animais , Glicina/análogos & derivados , Glicina/toxicidade , Lagos
3.
J Environ Sci Health B ; 56(3): 241-250, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33529073

RESUMO

Glyphosate can generate positive effects on turfgrass maintenance as a form of growth control by decreasing the expenses associated with mowing. However, there is little information about the effects of this herbicide on turfgrasses. This study aimed to evaluate the response of bermudagrass and zoysiagrass to the herbicide glyphosate as a growth regulator. Two studies were performed in a greenhouse and repeated at different times. The treatments involved application of glyphosate at 10 different rates (0, 5.625, 11.25, 22.5, 45, 90, 180, 360, 720, and 1.440 g ae ha-1) with four replicates. Evaluations of green cover by digital analysis, injury, and plant height were performed at 7, 14, 21, and 28 days after application, and shoot dry matter of clippings was determined for the last evaluation period. Bermudagrass and zoysiagrass presented variedtolerance to glyphosate toxicity. Overall, the digital analysis showed that green content was negatively influenced by the increase in visual injury caused by glyphosate application. Moreover, increasing the glyphosate rate decreased plant height and shoot dry matter in both turfgrasses. Glyphosate application rates up to 45 g ae ha-1 for bermudagrass and 90 g ae ha-1 for zoysiagrass decreased plant growth without affecting the factors analyzed in this study.


Assuntos
Glicina/análogos & derivados , Reguladores de Crescimento de Planta/farmacologia , Poaceae/efeitos dos fármacos , Poaceae/crescimento & desenvolvimento , Brasil , Cynodon/efeitos dos fármacos , Cynodon/crescimento & desenvolvimento , Glicina/farmacologia , Glicina/toxicidade , Herbicidas/farmacologia , Herbicidas/toxicidade , Reguladores de Crescimento de Planta/toxicidade , Folhas de Planta/efeitos dos fármacos , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Especificidade da Espécie
4.
Sci Total Environ ; 767: 145397, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33636765

RESUMO

Glyphosate (GLY) is an herbicide widely used in agriculture. First considered as non-toxic or slightly toxic to bees, GLY and its different formulations have shown, more recently, to affect negatively the survival, development and behavior of these insects, even when used in doses and concentrations recommended by the manufacturer. Thus, the results of research on the toxicity of GLY to bees are often conflicting, which makes a meta-analysis interesting for data integration, generating a statistically reliable result. Therefore, this study aimed to evaluate the GLY effects on mortality of bees through a meta-analysis. For this, a search was carried out in the databases Web of Science, CAPES (Coordination for the Improvement of Higher Education Personnel - Brazil), Scopus, and PubMed. Papers that evaluated the effect of GLY on bee mortality published between 1945 and October 2020, were considered. After obtaining the data, R software was used to perform the meta-analytical tests. Sixteen papers on mortality were selected with 34 data sets. Most of the sets demonstrated differences between the control and experimental groups, showing that the treatments with GLY caused higher mortality of bees. The results considering the methodology used (ingestion or contact), the phase of the biological cycle (adults or larvae), and the dose (ecologically relevant dose and recommended by the manufacturer) were different when compared with their respective control groups. Therefore, GLY can be considered toxic to bees. It is important to emphasize that this meta-analysis identified that papers assessing the toxicity of GLY to bees are still scarce, for both lethal and sublethal effects, mainly for stingless and solitary bee species.


Assuntos
Glicina , Herbicidas , Animais , Abelhas , Brasil , Glicina/análogos & derivados , Glicina/toxicidade , Herbicidas/toxicidade , Larva
5.
Mar Environ Res ; 165: 105247, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33429113

RESUMO

In this study the effects of a mixture of glyphosate (herbicide), 17a-ethinylestradiol (synthetic estrogen) and amyl salicylate (fragrance) to the mussel Mytilus galloprovincialis were evaluated. Mussels were exposed for 7 days to two realistic concentrations of the mixture (10 and 100 ng/L) and the effects on total haemocyte counts, haemocyte diameter and volume, haemocyte proliferation, haemolymph lactate dehydrogenase activity and haemocyte lysate lysozyme activity were measured. In addition, superoxide dismutase, catalase, acetylcholinesterase, glutathione-S-transferase and glutathione reductase activities were measured in gills and digestive gland. The survival-in-air test was also performed. Results demonstrated that the mixture affected both cellular and biochemical biomarkers, but not tolerance to aerial exposure of M. galloprovincialis. The negative effects recorded in this study suggested that more efforts should be done to assess the ecotoxicological risks posed by contaminant mixture to aquatic invertebrates.


Assuntos
Mytilus , Poluentes Químicos da Água , Animais , Biomarcadores , Catalase , Glicina/análogos & derivados , Glicina/toxicidade , Salicilatos , Poluentes Químicos da Água/toxicidade
6.
Bull Environ Contam Toxicol ; 106(4): 583-588, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33507346

RESUMO

This study was aimed at evaluating the possible interference of formulated glyphosate to the endocrine control of ovarian growth exerted by progesterone, in the estuarine crab Neohelice granulata. The addition of Roundup Ultramax® (0.2 mg/L of glyphosate in the incubation medium) was able to potentiate the stimulating effect of progesterone on total vitellogenic protein (Vg) content of ovarian pieces from crabs. Moreover, the sole addition of mifepristone (antagonist of progesterone receptors) was able to produce a decrement of the Vg content, which was not reverted by the addition of Roundup. A similar result was confirmed by means of histological analysis, which showed that mifepristone, both alone and in combination with Roundup, inhibited ovarian maturation, while Roundup alone increased it, in terms of a higher proportion of vitellogenic oocytes. We conclude that Roundup could stimulate the progesterone secretion exerted by the ovary and/or could act as a partial agonist of this hormone in the same tissue.


Assuntos
Braquiúros , Herbicidas , Animais , Feminino , Glicina/análogos & derivados , Glicina/toxicidade , Ovário , Progesterona
7.
Sci Total Environ ; 769: 145156, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33477045

RESUMO

Agricultural chemicals have the potential to become pollutants that adversely affect plant growth. Interactions between these compounds are likely, but potential synergies are under-researched. Multiwall carbon nanotubes are increasingly finding novel uses in agriculture, as delivery mechanisms and as slow-release fertilizers. There is potential for nanotubes to interact with other agricultural chemicals in unpredictable ways. To investigate this possibility, we examined interactions with glyphosate, a widely used herbicide that is also attracting increasing concern over its potential for non-target effects. Here we examined potential synergistic effects on hydroponically grown Arabidopsis thaliana. Single treatments did not affect plant growth significantly, or did only mildly. However, combined treatment significantly affected both plant root and shoot growth. High-level content of malondialdehyde and up-regulated of metabolic antioxidant molecules in plant indicated that combined group caused the strong oxidative damage, while the decreased of antioxidant enzyme activities indicated an imbalance between reactive oxygen species (ROS)and the antioxidant defense system due to the continuously generated ROS. Besides, several intermediate metabolites of unsaturated fatty acids synthesis pathways were up-regulated in combined treatment, which clarified that combined group changed membrane components. The increase of intermediate metabolites in combined group also reflected more energy consumption in the repairment of the disrupt of combined treatment. The synergistic effect observed was attributed to the accumulation of glyphosate resulting from permeability and transportability of the carbon nanotubes. Overall, the risk of nanotube-herbicide interaction suggests a caution use of nanotubes in agricultural applications.


Assuntos
Arabidopsis , Nanotubos de Carbono , Glicina/análogos & derivados , Glicina/toxicidade , Nanotubos de Carbono/toxicidade , Estresse Oxidativo
8.
Sci Total Environ ; 769: 144113, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33486169

RESUMO

Glyphosate is applied for dissection in no-till and post-emergence management in transgenic crops in agricultural fields near the Cerrado and Caatinga biomes. These biomes together represent 33.8% of the Brazilian territory, contributing to the maintenance of great world diversity in flora and fauna. Despite actions to protect them, the proximity with agricultural areas and intense use of glyphosate puts at risk the preservation of native vegetation due to the contamination via herbicide transport processes. Our objectives were: i) to determine the sensitivity of native species from the Cerrado and Caatinga to glyphosate contamination via drift and groundwater; ii) evaluate the level of sensitivity to glyphosate among the different organs of plants. The highest intoxications (upper 80%) were observed for Bauhinia cheilantha, Mimosa caesalpiniaefolia, Mimosa tenuiflora and Amburana cearensis due to drift simullation. The species with 90% of total dry matter reduction were Bauhinia cheilantha, Enterolobium contortisiliquum, Mimosa caesalpiniaefolia, Mimosa tenuiflora, Tabebuia aurea. B. cheilantha and M. tenuiflora are most affected by exposure to glyphosate drift, with 50% of total dry matter reduction when exposed to doses below 444,0 g ha-1. Leaf growth is more sensitive to glyphosate for drift exposure for most species. Hymenaea courbaril is an exception, with greater sensitivity to root growth (50% dry matter reduction at doses below 666,0 g ha-1). B. cheilantha is the species most sensitive to drift exposure; however, it showed complete tolerance to contamination in subsurface waters. Other species such as Anadenanthera macrocarpa and M. caesalpiniifolia are also sensitive to drift, but without reach 90% of total dry matter reduction. A. macrocarpa, M. caesalpiniifolia and T. aurea were tolerant to contamination by subsurface water. The differential tolerance of trees confirms glyphosate's potential as a species selection agent in the Cerrado and Caatinga biomes.


Assuntos
Herbicidas , Árvores , Brasil , Ecossistema , Glicina/análogos & derivados , Glicina/toxicidade , Herbicidas/toxicidade
11.
J Environ Sci Health B ; 56(3): 235-240, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33449826

RESUMO

Fertiactyl® is a foliar fertilizer with the potential to minimize the phytotoxicity effects caused by glyphosate drift in eucalyptus plants. As the interactions of the glyphosate and Fertiactyl® in tank mix on the plant behavior are not yet known, the objective was to evaluate the absorption and translocation of 14C-glyphosate, applied isolated and mixed in tank with Fertiactyl®, in young eucalyptus plants (clone I-144, Eucalyptus urophylla x E. grandis). The addition of Fertiactyl® to the mixture of 14C-glyphosate reduced the absorption by 94.3% in relation to the total absorbed at the end of the evaluation compared to plants treated only with 14C-glyphosate, i.e., Fertiactyl® protected the eucalyptus plants of the glyphosate intoxication by drift. The translocation rates from the treated leaves to the rest of the shoots and roots were low (<2% of the total recovered) in both treatments, suggest that restricted translocation is a mechanism of natural tolerance to glyphosate in plants of clone I-144. It is concluded that Fertiactyl®, mixed in the solution with glyphosate, protects young eucalyptus plants against glyphosate drift by reducing the amount of herbicide absorbed.


Assuntos
Eucalyptus/efeitos dos fármacos , Fertilizantes , Glicina/análogos & derivados , Herbicidas/farmacocinética , Radioisótopos de Carbono/farmacocinética , Eucalyptus/metabolismo , Glicina/farmacocinética , Glicina/toxicidade , Herbicidas/toxicidade , Folhas de Planta/efeitos dos fármacos , Brotos de Planta/efeitos dos fármacos , Distribuição Tecidual
12.
Artigo em Inglês | MEDLINE | ID: mdl-33498564

RESUMO

Glyphosate is a very effective herbicide and the main active ingredient in Roundup®-the most extensively used herbicide in the world. Since glyphosate is highly water soluble it reaches water bodies easily in surface water runoff. This prompted us to undertake an experiment to evaluate the effects of glyphosate in Roundup® on natural communities of marine microphytobenthos. Microphytobenthos communities were obtained from the environment, and after transporting them to the laboratory and acclimatizing them, they were tested under controlled conditions. Changes in microphytobenthos composition and structure and the deteriorating condition of the cells of community-forming organisms (assessed by analyzing changes in chloroplast shape) were used to assess the impact of Roundup® on endpoints. The tests indicated that microphytobenthic communities were relatively resistant to herbicide. The species richness of the communities probably enabled them to rebuild effectively. Sensitive species were replaced by those more tolerant of glyphosate. Only at the highest glyphosate concentration (8.5 g·dm-3) tested was a strong negative effect noted that limited community abundance and eliminated some of the organisms. The dominant diatoms in the communities were replaced by intensively developing cyanobacteria, which ultimately comprised nearly 60% of all the cells observed in the communities.


Assuntos
Herbicidas , Microalgas , Poluentes Químicos da Água , Glicina/análogos & derivados , Glicina/toxicidade , Herbicidas/toxicidade , Poluentes Químicos da Água/toxicidade
13.
Chemosphere ; 262: 127785, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182149

RESUMO

Although glyphosate is widely used for weed pest control, it might have negative side effects on natural enemies. Wolf spiders are one of the most representative predators found on soybean crops in Uruguay, preying on a wide variety of potential pests. However, the sublethal effects that pesticides might have on this group have been poorly explored for South American species. Herein, we explored the sublethal effects of glyphosate on the functional response of the wolf spider Hogna cf. bivittata against three potential pest insects, namely ant (Acromyrmex sp.), caterpillar (Anticarsia gemmatalis), and cricket (Miogryllus sp.). We contaminated residually adult females of the species Hogna cf. bivittata with glyphosate (Roundup®) and compared their functional response against non-contaminated spiders. We did not observe any mortality during the study. We found that overall Hogna cf. bivittata showed a functional response type II against crickets and caterpillars but no functional response to ants. Contaminated spiders killed less ants and caterpillars in comparison to the control group, probably as a consequence of the irritating effects of glyphosate. We did not observe differences in functional response to crickets at the evaluated densities, probably as a consequence of the low capture rate against this prey. Although glyphosate does not specifically target spiders, it might have negative sublethal effects on native predators such as Hogna cf. bivittata. Further studies should explore effect of glyphosate on other native predators from South American crops.


Assuntos
Glicina/análogos & derivados , Praguicidas/toxicidade , Aranhas/efeitos dos fármacos , Animais , Formigas , Produtos Agrícolas , Feminino , Glicina/toxicidade , Gryllidae , Mariposas , Comportamento Predatório/efeitos dos fármacos , Uruguai
14.
Environ Pollut ; 270: 116179, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33348142

RESUMO

The developing nervous system is highly vulnerable to environmental toxicants especially pesticides. Glyphosate pesticide induces neurotoxicity both in humans and rodents, but so far only when exposed to higher concentrations. A few studies, however, have also reported the risk of general toxicity of glyphosate at concentrations comparable to allowable limits set up by environmental protection authorities. In vitro data regarding glyphosate neurotoxicity at concentrations comparable to maximum permissible concentrations in drinking water is lacking. In the present study, we established an in vitro assay based upon neural stem cells (NSCs) from the subventricular zone of the postnatal mouse to decipher the effects of two maximum permissible concentrations of glyphosate in drinking water on the basic neurogenesis processes. Our results demonstrated that maximum permissible concentrations of glyphosate recognized by environmental protection authorities significantly reduced the cell migration and differentiation of NSCs as demonstrated by the downregulation of the expression levels of the neuronal ß-tubulin III and the astrocytic S100B genes. The expression of the cytoprotective gene CYP1A1 was downregulated whilst the expression of oxidative stresses indicator gene SOD1 was upregulated. The concentration comparable to non-toxic human plasma concentration significantly induced cytotoxicity and activated Ca2+ signalling in the differentiated culture. Our findings demonstrated that the permissible concentrations of glyphosate in drinking water recognized by environmental protection authorities are capable of inducing neurotoxicity in the developing nervous system.


Assuntos
Água Potável , Herbicidas , Células-Tronco Neurais , Animais , Água Potável/análise , Glicina/análogos & derivados , Glicina/toxicidade , Herbicidas/análise , Ventrículos Laterais/química , Camundongos , Células-Tronco Neurais/química
15.
Microbiome ; 8(1): 170, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33339542

RESUMO

BACKGROUND: Research around the weedkiller Roundup is among the most contentious of the twenty-first century. Scientists have provided inconclusive evidence that the weedkiller causes cancer and other life-threatening diseases, while industry-paid research reports that the weedkiller has no adverse effect on humans or animals. Much of the controversial evidence on Roundup is rooted in the approach used to determine safe use of chemicals, defined by outdated toxicity tests. We apply a system biology approach to the biomedical and ecological model species Daphnia to quantify the impact of glyphosate and of its commercial formula, Roundup, on fitness, genome-wide transcription and gut microbiota, taking full advantage of clonal reproduction in Daphnia. We then apply machine learning-based statistical analysis to identify and prioritize correlations between genome-wide transcriptional and microbiota changes. RESULTS: We demonstrate that chronic exposure to ecologically relevant concentrations of glyphosate and Roundup at the approved regulatory threshold for drinking water in the US induce embryonic developmental failure, induce significant DNA damage (genotoxicity), and interfere with signaling. Furthermore, chronic exposure to the weedkiller alters the gut microbiota functionality and composition interfering with carbon and fat metabolism, as well as homeostasis. Using the "Reactome," we identify conserved pathways across the Tree of Life, which are potential targets for Roundup in other species, including liver metabolism, inflammation pathways, and collagen degradation, responsible for the repair of wounds and tissue remodeling. CONCLUSIONS: Our results show that chronic exposure to concentrations of Roundup and glyphosate at the approved regulatory threshold for drinking water causes embryonic development failure and alteration of key metabolic functions via direct effect on the host molecular processes and indirect effect on the gut microbiota. The ecological model species Daphnia occupies a central position in the food web of aquatic ecosystems, being the preferred food of small vertebrates and invertebrates as well as a grazer of algae and bacteria. The impact of the weedkiller on this keystone species has cascading effects on aquatic food webs, affecting their ability to deliver critical ecosystem services. Video Abstract.


Assuntos
Daphnia/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Glicina/análogos & derivados , Redes e Vias Metabólicas/efeitos dos fármacos , Animais , Glicina/toxicidade
16.
PLoS One ; 15(12): e0244798, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33382820

RESUMO

Litchi fruits are a nutritious and commercial crop in the Indian state of Bihar. Litchi fruit contains a toxin, methylene cyclopropyl-glycine (MCPG), which is known to be fatal by causing encephalitis-related deaths. This is especially harmful when consumed by malnourished children. The first case of litchi toxicity was reported in Bihar in 2011. A similar event was recorded in 2014 among children admitted to the Muzaffarpur government hospital, Bihar. Litchi samples sent to ICMR-NIN were analyzed and MCPG was found to be present in both the pulp and seed of the fruit. Diethyl phosphate (DEP) metabolites were found in the urine samples of children who had consumed litchi fruit from this area indicating exposure to pesticide. The presence of both MCPG in litchi and DEP metabolites in urine samples highlights the need to conduct a comprehensive investigation that examines all factors of toxicity.


Assuntos
Ciclopropanos/toxicidade , Encefalite/induzido quimicamente , Glicina/análogos & derivados , Litchi/toxicidade , Organofosfatos/urina , Envenenamento/diagnóstico , Criança , Ciclopropanos/análise , Ciclopropanos/urina , Surtos de Doenças , Encefalite/urina , Frutas , Glicina/análise , Glicina/toxicidade , Glicina/urina , Humanos , Índia , Litchi/química , Espectrometria de Massas , Praguicidas/urina , Envenenamento/urina
17.
Ecotoxicol Environ Saf ; 203: 111013, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888588

RESUMO

Multiple pesticides originating from plant protection treatments and the treatment of pests infecting honey bees are frequently detected in beehive matrices. Therefore, winter honey bees, which have a long life span, could be exposed to these pesticides for longer periods than summer honey bees. In this study, winter honey bees were exposed through food to the insecticide imidacloprid, the fungicide difenoconazole and the herbicide glyphosate, alone or in binary and ternary mixtures, at environmental concentrations (0 (controls), 0.1, 1 and 10 µg/L) for 20 days. The survival of the honey bees was significantly reduced after exposure to these 3 pesticides individually and in combination. Overall, the combinations had a higher impact than the pesticides alone with a maximum mortality of 52.9% after 20 days of exposure to the insecticide-fungicide binary mixture at 1 µg/L. The analyses of the surviving bees showed that these different pesticide combinations had a systemic global impact on the physiological state of the honey bees, as revealed by the modulation of head, midgut and abdomen glutathione-S-transferase, head acetylcholinesterase, abdomen glucose-6-phosphate dehydrogenase and midgut alkaline phosphatase, which are involved in the detoxification of xenobiotics, the nervous system, defenses against oxidative stress, metabolism and immunity, respectively. These results demonstrate the importance of studying the effects of chemical cocktails based on low realistic exposure levels and developing long-term tests to reveal possible lethal and adverse sublethal interactions in honey bees and other insect pollinators.


Assuntos
Abelhas/fisiologia , Fungicidas Industriais/toxicidade , Herbicidas/toxicidade , Inseticidas/toxicidade , Praguicidas/toxicidade , Animais , Dioxolanos/toxicidade , Sinergismo Farmacológico , Glicina/análogos & derivados , Glicina/toxicidade , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Polinização/efeitos dos fármacos , Triazóis/toxicidade
18.
Environ Pollut ; 267: 115483, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32889518

RESUMO

Fucus virsoides is an ecologically important canopy-forming brown algae endemic to the Adriatic Sea. Once widespread in marine coastal areas, this species underwent a rapid population decline and is now confined to small residual areas. Although the reasons behind this progressive disappearance are still a matter of debate, F. virsoides may suffer, like other macroalgae, from the potential toxic effects of glyphosate-based herbicides. Here, through a transcriptomic approach, we investigate the molecular basis of the high susceptibility of this species to glyphosate solution, previously observed at the morphological and eco-physiological levels. By simulating runoff event in a factorial experiment, we exposed F. virsoides to glyphosate (Roundup® 2.0), either alone or in association with nutrient enrichment, highlighting significant alterations of gene expression profiles that were already visible after three days of exposure. In particular, glyphosate exposure determined the near-complete expression shutdown of several genes involved in photosynthesis, protein synthesis and stress response molecular pathways. Curiously, these detrimental effects were partially mitigated by nutrient supplementation, which may explain the survival of relict population in confined areas with high nutrient inputs.


Assuntos
Fucus , Herbicidas , Feófitas , Animais , Glicina/análogos & derivados , Glicina/toxicidade , Herbicidas/toxicidade
19.
Chemosphere ; 261: 127782, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32750624

RESUMO

Pesticide mixtures are frequent in freshwaters systems around the world, threatening the biota exposed to these conditions. The aim of this study was to determine the single and joint effect of two widely used pesticides in southern South America on a widely distributed fish species. In a 96-h assay, individuals of Cnesterodon decemmaculatus were exposed to 0.84 nL/L and 8.4 nL/L of Clorfox and 0.2 mg/L and 2 mg/L of Roundup Max, commercial formulations of chlorpyrifos and glyphosate, respectively. Also, there were four mixture treatments with all the possible combinations of both pesticides. A multi-level approach was carried out to assess their effects covering the following relevant biomarkers: behavior (immobile time, line crossings and average speed), somatic conditions (Fulton condition factor and hepatosomatic index), serum parameters (cortisol levels, lactate dehydrogenase (LDH), and creatine phosphokinase activity (CPK)), brain and muscle acetylcholinesterase and cytological characteristics (micronuclei frequency and nuclear abnormalities in erythrocytes). Our results showed that Clorfox exposures affect behavioral parameters, serum cortisol, and nuclear characteristics of erythrocytes. Roundup Max affects only the cortisol levels whereas mixture treatments have an effect on behavioral parameters, cortisol levels, LDH and CPK activities, and nuclear characteristics of erythrocytes. Potentiation was the main interaction at the lowest concentrations of both pesticides whereas antagonism occurred at the highest concentrations of both pesticides. These results are highly significant since they arise from an integrated ecotoxicological assessment at several levels of biological organization but even more important is that the potentiated effects of the mixtures we registered are environmentally relevant concentrations.


Assuntos
Clorpirifos/toxicidade , Ciprinodontiformes/fisiologia , Glicina/análogos & derivados , Praguicidas/toxicidade , Poluentes Químicos da Água/toxicidade , Acetilcolinesterase , Animais , Bioensaio , Biomarcadores , Ecotoxicologia , Água Doce , Glicina/toxicidade , Praguicidas/análise , América do Sul , Poluentes Químicos da Água/análise
20.
Ecotoxicol Environ Saf ; 204: 111108, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32798750

RESUMO

Honeybees (Apis mellifera) play an important role in agriculture worldwide. Several factors including agrochemicals can affect honey bee health including habitat fragmentation, pesticide application, and pests. The growing human population and subsequent increasing crop production have led to widespread use of agrochemicals and there is growing concern that pollinators are being negatively impacted by these pesticides. The present study compares acute exposure to imidacloprid (0.2 and 0.4 mgL-1), ethion (80 and 106.7 mgL-1) or glyphosate (0.12 and 0.24 mgL-1) on aversive learning and movement, to chronic exposure at these and higher concentrations on movement, circadian rhythms, and survival in honey bee foragers. For acute learning studies, a blue/yellow shuttle box experiment was conducted; we observed honey bee choice following aversive and neutral stimuli. In learning studies, control bees spent >50% of the time on yellow which is not consistent with previous color bias literature in the subspecies or region of the study. The learning apparatus was also used to estimate mobility effects within 20 min of exposure. Chronic exposure (up to 2 weeks) with the above metrics was recorded by an automated monitoring system. In chronic exposure experiments, RoundUp®, was also tested to compare to its active ingredient, glyphosate. We found that imidacloprid and ethion have negative impacts on aversive learning and movement following a single-dose and that chronic exposure effects were dose-dependent for these two insecticides. In contrast, glyphosate had no effect on learning and less of an effect on movement; RoundUp® showed dose-dependent results on circadian rhythmicity. Overall, the results suggest that short-term exposure to imidacloprid and ethion adversely affect honey bee foragers and chronic exposure to glyphosate may affect pollination success.


Assuntos
Abelhas/fisiologia , Inseticidas/toxicidade , Animais , Glicina/análogos & derivados , Glicina/toxicidade , Aprendizagem/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Compostos Organotiofosforados/toxicidade , Polinização
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