Ecotoxicological effects of commercial herbicides on the reproductive system of aquatic arthropod Limnocoris submontandoni (Hemiptera: Naucoridae) / Efeitos ecotoxicológicos de herbicidas comerciais no sistema reprodutivo do artrópode aquático Limnocoris submontandoni (Hemiptera: Naucoridae)

Abstract Worldwide, conventional agriculture makes extensive use of pesticides. Although the effects of herbicides are relatively well known in terms of environmental impacts on non-target organisms, there is very little scientific evidence regarding the impacts of herbicide residues on aquatic arthropods from tropical conservation areas. This study evaluates for the first time the toxicity of the herbicides ametryn, atrazine, and clomazone on the aquatic insect Limnocoris submontandoni (Hemiptera: Naucoridae). The lethal concentration (LC50) of herbicides was evaluated for these insects, as well as the effect of the herbicides on the insects' tissues and testicles. The estimated LC50 was 1012.41, 192.42, and 46.09 mg/L for clomazone, atrazine, and ametryn, respectively. Spermatocyte and spermatid changes were observed under the effect of atrazine, and effects on spermatogenesis were observed for some concentrations of clomazone, with apparent recovery after a short time. Our results provide useful information on the effects of herbicide residues in aquatic systems. This information can help minimize the risk of long-term reproductive effects in non-target species that have been previously overlooked in ecotoxicology studies.

Resumo Em todo o mundo, a agricultura convencional faz uso extensivo de pesticidas. Embora os efeitos dos herbicidas sejam relativamente bem conhecidos em termos de impactos ambientais em organismos não-alvo, há pouca evidência científica sobre os impactos de resíduos de herbicidas em artrópodes aquáticos de áreas de conservação tropicais. Este estudo avalia pela primeira vez a toxicidade dos herbicidas ametryn, atrazine e clomazone sobre o inseto aquático Limnocoris submontandoni (Hemiptera: Naucoridae). A concentração letal (LC50) de herbicidas foi avaliada para esses insetos, bem como o efeito dos herbicidas nos tecidos e testículos dos insetos. A LC50 estimada foi de 1012,41, 192,42 e 46,09 mg/L para clomazone, atrazine e ametryn, respectivamente. Alterações nos espermatócitos e espermátides foram observadas sob o efeito de atrazine, e efeitos na espermatogênese foram observados para algumas concentrações de clomazone, com aparente recuperação após um curto período de tempo. Nossos resultados fornecem informações úteis sobre os efeitos de resíduos de herbicidas em sistemas aquáticos. Essas informações podem ajudar a minimizar o risco de efeitos reprodutivos de longo prazo em espécies não-alvo que foram negligenciadas anteriormente em estudos de ecotoxicologia.

Phytotoxic and cytogenotoxic assessment of glyphosate on Lactuca sativa L / Avaliação fitotóxica e citogenotóxica do glifosato em Lactuca sativa L

The active ingredient glyphosate is the most commercialized herbicide on the world market due to its capability in eliminating weeds. However, it can harm the development of non-target organisms and threaten environmental quality. This study analyzed the effects of potentially toxic concentrations of glyphosate on germination, growth, cell cycle and genomic stability of Lactuca sativa L., and identified the most sensitive variables for assessing the toxicity of this herbicide to this biomonitor. Seeds of L. sativa were germinated in Petri dishes containing a sheet of filter paper moistened with 5 mL of a concentration of glyphosate (1.34, 3.35, 6.70, 10.05, 13.40 mg L-1). Controls consisted of distilled water (negative) and 3 mg L-1 CuSO4 (positive). Macroscopic and microscopic variables were analyzed. The germination of L. sativa was not affected by the concentrations of glyphosate. Root length and shoot height of the plants and the mitotic index decreased from the lowest concentration tested on. The chromosomal anomaly index and frequency of micronuclei increased by 3.2 and 22 times, respectively, with the presence of the lowest concentration of glyphosate compared to the negative control. The observed phytotoxic and cytogenotoxic effects demonstrate the negative influence that glyphosate has on the development of L. sativa. Root length and microscopic variables showed the highest sensitivity. This study warns of the possible harmful effects that glyphosate can have on non-target organisms and suggests greater control over the use of this herbicide to mitigate its environmental impact.

O ingrediente ativo glifosato é o herbicida mais comercializado do mercado mundial, pela sua capacidade de eliminar as plantas daninhas. No entanto, ele pode prejudicar o desenvolvimento dos organismos não-alvo e ameaçar a qualidade do ambiente. O estudo teve como objetivo analisar os efeitos de concentrações potencialmente tóxicas de glifosato sobre a germinação, o crescimento, o ciclo celular e a estabilidade genômica de Lactuca sativa L., e identificar as variáveis mais sensíveis para avaliar a toxicidade deste herbicida ao biomonitor. Sementes de L. sativa foram germinadas em placas de Petri contendo uma folha de papel-filtro umedecida com 5 mL das concentrações de glifosato (1,34, 3,35, 6,70, 10,05, 13,40 mg L-1). Os controles consistiram em água destilada (negativo) e 3 mg L-1 de CuSO4 (positivo). Variáveis macroscópicas e microscópicas foram analisadas. A germinação de L. sativa não foi afetada pelas concentrações de glifosato. O comprimento da raiz e a altura da parte aérea das plantas e o índice mitótico reduziram desde a menor concentração testada. O índice de anomalias cromossômicas e a frequência de micronúcleos aumentaram, respectivamente, 3,2 e 22 vezes na presença da menor concentração de glifosato em comparação ao controle negativo. Os efeitos fitotóxicos e citogenotóxicos observados demonstram a interferência negativa do herbicida no desenvolvimento de L. sativa. O comprimento da raiz e as variáveis microscópicas foram as que apresentaram maior sensibilidade. Este estudo alerta sobre os possíveis efeitos prejudiciais que o glifosato pode provocar nos organismos não-alvo, sugerindo um maior controle quanto à utilização deste herbicida, a fim de mitigar o seu impacto ambiental.

Glyphosate-resistant hairy fleabane (Conyza bonariensis) exhibits a larger number of trichomes and altered stomatal density relative to the susceptible counterpart

Following the adoption of Roundup Ready crops, glyphosate spraying frequency increased, while the use of other herbicide modes of action was neglected. Herbicide-resistant biotypes were reported in three major Conyza species in Brazil, including Conyza bonariensis, increasing growers' bottom line. Considering that leaf surface structures affect proper herbicide deposition, uptake, and performance, this study aimed to characterize epicuticular surface components in glyphosate-resistant (R) and -susceptible (S) C. bonariensis. Conyza spp. seeds were collected in 36 locations in Brazil, and plants were subjected to resistance screening tests by spraying glyphosate at 720 and 1440 g ae ha-1 (0.5X and 1X the label recommended rate, respectively). For resistance level characterization, C. bonariensis biotypes with contrasting responses were selected for glyphosate dose-response assays. Leaf tissues for epicuticular surface analysis were harvested from newly-obtained R and S biotypes at two growth stages. Histological cuts were made on a leaf area of 25 mm² with a blade. Samples were fixed in Karnowsky solution, gradually changed to 100% ethanol, critical-point dried with CO2, and coated with gold, followed by stomatal and trichome density quantification using scanning electron microscopy. Results indicated a poor control with glyphosate in 33 of 36 Conyza spp. biotypes, and a high (31.5) resistance factor was calculated after dose-response trials. Leaf surface analysis indicated that C. bonariensis leaves are amphistomatic and exhibit tectorial trichomes. A higher number of trichomes and altered stomatal density (number.mm²) were quantified in R compared to the S counterpart, potentially reducing glyphosate uptake and effectiveness.

Intoxicação cutânea grave por Paraquat / Serious skin poisoning by Paraquat

O Paraquat é um herbicida não seletivo altamente tóxico, sendo responsável por altas taxas de letalidade acidentais ou provocadas, devido, principalmente, à insuficiência respiratória. Apesar de a intoxicação por via oral ser a principal e mais grave, o contato prolongado com a substância em uma grande área corporal pode gerar uma toxicidade similar e levar ao óbito ­ fato pouco elucidado na literatura. Este é o relato de caso de um homem de 22 anos, que foi admitido em um hospital devido a queixas de mal-estar, náuseas, febre, cefaleia, dor abdominal, diarreia, queimaduras e dispneia. A suspeita diagnóstica inicial foi de hantavirose, leptospirose, dengue e tromboembolismo pulmonar e, posteriormente, foi comprovado intoxicação exógena com agrotóxico por via inalatória e cutânea. Exames de imagem revelaram fibrose pulmonar difusa e ele também apresentou alterações renais, hepáticas e coagulatórias. Como não há antídoto específico, foi empregado tratamento sintomático e suportivo, com uso de carvão ativado, antibióticos, corticoides, antioxidantes e hemodiálise. No entanto, o paciente teve uma piora progressiva do quadro, vindo a óbito devido à síndrome da angústia respiratória aguda e fibrose pulmonar. O Paraquat, embora proibido no Brasil em 2020, continua sendo utilizado de forma ilegal. Além disso, seu substituto, o Diquat, possui toxicidade semelhante. Assim, é fundamental que os profissionais da saúde reconheçam o diagnóstico da intoxicação por tais substâncias e suas diferentes vias de exposição. Também são necessárias novas medidas de fiscalização das substâncias e maior investimento em educação em saúde para evitar exposições acidentais, assim como relatado (AU).

Paraquat is a highly toxic non-selective herbicide and is responsible for high accidental or provoked lethality rates, mainly due to respiratory failure. Although oral poisoning is the primary and most severe, prolonged contact with the substance in a large body area can lead to similar toxicity and death ­ a fact that is little elucidated in the literature. This is the case report of a 22-year-old man admitted to a hospital due to complaints of malaise, nausea, fever, headache, abdominal pain, diarrhea, burns and dyspnea. The initial diagnostic suspicion was hantaviruses, leptospirosis, dengue and pulmonary thromboembolism, and there was subsequently proven exogenous intoxication with pesticides by inhalation and cutaneous route. Imaging tests revealed diffuse pulmonary fibrosis and he also had renal, hepatic and coagulation alterations. As there is no specific antidote, symptomatic and supportive treatment was performed using activated charcoal, antibiotics, corticosteroids, antioxidants and hemodialysis. However, the patient had a progressive worsening of the condition and died due to acute respiratory distress syndrome and pulmonary fibrosis. Paraquat, although banned in Brazil in 2020, continues to be used illegally. In addition, its substitute, the Diquat, has similar toxicity. Thus, it is essential that health professionals recognize the diagnosis of intoxication by such substances and their different exposure routes. New control measures for these substances and greater investment in health education are also needed to prevent accidental exposure, as reported (AU).

Amazonian soil fungi are efficient degraders of glyphosate herbicide; novel isolates of Penicillium, Aspergillus, and Trichoderma / Os fungos do solo amazônico são degradadores eficientes do herbicida glifosato; novos isolados de Penicillium, Aspergillus e Trichoderma

Abstract Pesticide residues that contaminate the environment circulate within the hydrological cycle can accumulate within the food chain and cause problems to both environmental and human health. Microbes, however, are well known for their metabolic versatility and the ability to degrade chemically stable substances, including recalcitrant xenobiotics. The current study focused on bio-prospecting within Amazonian rainforest soils to find novel strains fungi capable of efficiently degrading the agriculturally and environmentally ubiquitous herbicide, glyphosate. Of 50 fungal strains isolated (using culture media supplemented with glyphosate as the sole carbon-substrate), the majority were Penicillium strains (60%) and the others were Aspergillus and Trichoderma strains (26 and 8%, respectively). All 50 fungal isolates could use glyphosate as a phosphorous source. Eight of these isolates grew better on glyphosate-supplemented media than on regular Czapek Dox medium. LC-MS revealed that glyphosate degradation by Penicillium 4A21 resulted in sarcosine and aminomethylphosphonic acid.

Resumo Resíduos de agrotóxicos que contaminam o meio ambiente circulam no ciclo hidrológico, podendo se acumular na cadeia alimentar e causar problemas tanto à saúde ambiental quanto humana. Por sua vez, microrganismos são bem conhecidos por sua versatilidade metabólica e capacidade de degradar substâncias quimicamente estáveis, incluindo xenobióticos recalcitrantes. O estudo atual se concentrou na bioprospecção nos solos da floresta amazônica para encontrar novas linhagens de fungos capazes de degradar com eficiência o herbicida onipresente na agricultura e no meio ambiente, o glifosato. Entre os 50 fungos isolados (usando meio de cultura suplementado com glifosato como única fonte de carbono), a maioria eram isolados do gênero Penicillium (60%) e os outros eram isolados de Aspergillus e Trichoderma (26 e 8%, respectivamente). Todos os 50 isolados de fungos foram capazes de usar glifosato como fonte de fósforo. Oito desses isolados cresceram melhor em meio suplementado com glifosato do que em meio Czapek Dox regular. LC-MS revelou que a degradação do glifosato por Penicillium 4A21 resultou nos metabólitos sarcosina e ácido aminometilfosfônico.

Arbuscular mycorrhizal fungi activity in the rhizosphere of tree seedlings subjected to residual herbicides / Atividade de fungos micorrízicos arbusculares na rizosfera de mudas de árvores submetidas a herbicidas residuais

Abstract Trees occurring on the margins of agricultural areas can mitigate damage from residual herbicides. Rhizospheric microbial activity associated with trees is one of the main remedial capacity indicators. The objective of this study was to evaluate the rhizospheric microbiological activity in tree species subjected to the herbicides atrazine and sulfentrazone via the rhizosphere. The experiment was designed in four blocks and a 6 × 3 factorial scheme. The first factor consisted of six tree species from Brazil and the second of atrazine, sulfentrazone, and water solutions. Four herbicide applications were performed via irrigation. The total dry mass of the plants, mycorrhizal colonization, number of spores, basal respiration of the rhizospheric soil, and survival rate of bioindicator plants after phytoremediation were determined. Trichilia hirta had higher biomass when treated with atrazine and sulfentrazone. Herbicides decreased the microbial activity in Triplaris americana and did not affect the microbiological indicators of Myrsine gardneriana, Schizolobium parahyba, and Toona ciliata. Fewer bioindicator plants survived in soil with Triplaris americana and sulfentrazone. Microbiological indicators were influenced in different ways between species by the presence of herbicides in the rhizosphere.

Resumo As árvores que ocorrem nas margens das áreas agrícolas podem mitigar os danos dos herbicidas residuais. A atividade microbiana rizosférica associada às árvores é um dos principais indicadores de capacidade corretiva. O objetivo deste trabalho foi avaliar a atividade microbiológica rizosférica em espécies arbóreas submetidas aos herbicidas atrazina e sulfentrazone via rizosfera. O experimento foi estruturado em quatro blocos e esquema fatorial 6 × 3. O primeiro fator consistiu em seis espécies de árvores do Brasil e o segundo em soluções de atrazine, sulfentrazone e água. Quatro aplicações de herbicidas foram realizadas via irrigação. Foram determinados a massa seca total das plantas, colonização micorrízica, número de esporos, respiração basal do solo rizosférico e taxa de sobrevivência de plantas bioindicadoras após fitorremediação. Trichilia hirta apresentou maior biomassa quando tratada com atrazina e sulfentrazone. Os herbicidas diminuíram a atividade microbiana em Triplaris americana e não afetaram os indicadores microbiológicos de Myrsine gardneriana, Schizolobium parahyba e Toona ciliata. Menos plantas bioindicadoras sobreviveram no solo com Triplaris americana e sulfentrazone. Os indicadores microbiológicos foram influenciados de formas distintas entre as espécies pela presença dos herbicidas na rizosfera.

Normalized difference vegetation index for desiccation evaluation with glyphosate + 2, 4-D in magnetized spray solution / Índice de vegetação por diferença normalizada para avaliação de dessecação com glyphosate + 2, 4-D em calda magnetizada

Abstract Water magnetization and geoprocessing are increasingly utilized tools in weed management. Our objective was to study the influence of water magnetization on herbicide efficiency and to verify whether there is a relationship between control scores and the normalized difference vegetation index (NDVI). In the laboratory experiment, water was subjected to magnetization and evaluated with respect to four characteristics. In the field experiment, plots of Brachiaria grass were subjected to treatments in a factorial scheme (6 × 2 + 1). Six herbicidal factors (doses of glyphosate and glyphosate + 2,4-D) and the magnetization or absence of magnetization of the spray solution were evaluated and compared against the control treatment (without spraying). Weed control assessments were carried out six times. Images were obtained using an embedded multispectral camera to determine the NDVI values. Data related to water characteristics were analyzed using the t test. Weed control and NDVI data were subjected to analysis of variance and are presented in regression graphs. Dispersion analysis of NDVI data was performed according to the control scores. The magnetization process decreased the pH of the water and increased the surface tension, but it did not influence the control scores or the NDVI. As the glyphosate dose was increased, the control scores were higher and the NDVI values were lower. Magnetized water did not affect the biological efficiency of the herbicides, and there was a strong correlation between the control scores and the NDVI values.

Resumo A magnetização da água e o geoprocessamento são ferramentas cada vez mais utilizadas no manejo de ervas daninhas. Nosso objetivo foi estudar a influência da magnetização da água na eficiência do herbicida e verificar se existe uma relação entre os escores de controle e o índice de vegetação por diferença normalizada (NDVI). No experimento de laboratório, a água foi submetida à magnetização e avaliada em relação a quatro características. No experimento de campo, parcelas de capim-braquiária foram submetidas a tratamentos em esquema fatorial (6 × 2 + 1). Seis fatores herbicidas (doses de glyphosate e glyphosate + 2,4-D) e a magnetização ou ausência de magnetização da calda foram avaliados e comparados com o tratamento controle (sem pulverização). Avaliações de controle de plantas daninhas foram realizadas seis vezes. As imagens foram obtidas usando uma câmera multiespectral incorporada para determinar os valores de NDVI. Os dados relacionados às características da água foram analisados ​​por meio do teste t. O controle de plantas daninhas e os dados de NDVI foram submetidos à análise de variância e são apresentados em gráficos de regressão. A análise de dispersão dos dados NDVI foi realizada de acordo com os escores de controle. O processo de magnetização diminuiu o pH da água e aumentou a tensão superficial, mas não influenciou nos escores de controle ou no NDVI. Conforme a dose de glyphosate foi aumentada, os escores de controle foram maiores e os valores de NDVI foram menores. A água magnetizada não afetou a eficiência biológica dos herbicidas, e houve uma forte correlação entre os escores de controle e os valores de NDVI.

Amazonian soil fungi are efficient degraders of glyphosate herbicide; novel isolates of Penicillium, Aspergillus, and Trichoderma / Os fungos do solo amazônico são degradadores eficientes do herbicida glifosato; novos isolados de Penicillium, Aspergillus e Trichoderma

Pesticide residues that contaminate the environment circulate within the hydrological cycle can accumulate within the food chain and cause problems to both environmental and human health. Microbes, however, are well known for their metabolic versatility and the ability to degrade chemically stable substances, including recalcitrant xenobiotics. The current study focused on bio-prospecting within Amazonian rainforest soils to find novel strains fungi capable of efficiently degrading the agriculturally and environmentally ubiquitous herbicide, glyphosate. Of 50 fungal strains isolated (using culture media supplemented with glyphosate as the sole carbon-substrate), the majority were Penicillium strains (60%) and the others were Aspergillus and Trichoderma strains (26 and 8%, respectively). All 50 fungal isolates could use glyphosate as a phosphorous source. Eight of these isolates grew better on glyphosate-supplemented media than on regular Czapek Dox medium. LC-MS revealed that glyphosate degradation by Penicillium 4A21 resulted in sarcosine and aminomethylphosphonic acid.

Resíduos de agrotóxicos que contaminam o meio ambiente circulam no ciclo hidrológico, podendo se acumular na cadeia alimentar e causar problemas tanto à saúde ambiental quanto humana. Por sua vez, microrganismos são bem conhecidos por sua versatilidade metabólica e capacidade de degradar substâncias quimicamente estáveis, incluindo xenobióticos recalcitrantes. O estudo atual se concentrou na bioprospecção nos solos da floresta amazônica para encontrar novas linhagens de fungos capazes de degradar com eficiência o herbicida onipresente na agricultura e no meio ambiente, o glifosato. Entre os 50 fungos isolados (usando meio de cultura suplementado com glifosato como única fonte de carbono), a maioria eram isolados do gênero Penicillium (60%) e os outros eram isolados de Aspergillus e Trichoderma (26 e 8%, respectivamente). Todos os 50 isolados de fungos foram capazes de usar glifosato como fonte de fósforo. Oito desses isolados cresceram melhor em meio suplementado com glifosato do que em meio Czapek Dox regular. LC-MS revelou que a degradação do glifosato por Penicillium 4A21 resultou nos metabólitos sarcosina e ácido aminometilfosfônico.

Arbuscular mycorrhizal fungi activity in the rhizosphere of tree seedlings subjected to residual herbicides / Atividade de fungos micorrízicos arbusculares na rizosfera de mudas de árvores submetidas a herbicidas residuais

Trees occurring on the margins of agricultural areas can mitigate damage from residual herbicides. Rhizospheric microbial activity associated with trees is one of the main remedial capacity indicators. The objective of this study was to evaluate the rhizospheric microbiological activity in tree species subjected to the herbicides atrazine and sulfentrazone via the rhizosphere. The experiment was designed in four blocks and a 6 × 3 factorial scheme. The first factor consisted of six tree species from Brazil and the second of atrazine, sulfentrazone, and water solutions. Four herbicide applications were performed via irrigation. The total dry mass of the plants, mycorrhizal colonization, number of spores, basal respiration of the rhizospheric soil, and survival rate of bioindicator plants after phytoremediation were determined. Trichilia hirta had higher biomass when treated with atrazine and sulfentrazone. Herbicides decreased the microbial activity in Triplaris americana and did not affect the microbiological indicators of Myrsine gardneriana, Schizolobium parahyba, and Toona ciliata. Fewer bioindicator plants survived in soil with Triplaris americana and sulfentrazone. Microbiological indicators were influenced in different ways between species by the presence of herbicides in the rhizosphere.

As árvores que ocorrem nas margens das áreas agrícolas podem mitigar os danos dos herbicidas residuais. A atividade microbiana rizosférica associada às árvores é um dos principais indicadores de capacidade corretiva. O objetivo deste trabalho foi avaliar a atividade microbiológica rizosférica em espécies arbóreas submetidas aos herbicidas atrazina e sulfentrazone via rizosfera. O experimento foi estruturado em quatro blocos e esquema fatorial 6 × 3. O primeiro fator consistiu em seis espécies de árvores do Brasil e o segundo em soluções de atrazine, sulfentrazone e água. Quatro aplicações de herbicidas foram realizadas via irrigação. Foram determinados a massa seca total das plantas, colonização micorrízica, número de esporos, respiração basal do solo rizosférico e taxa de sobrevivência de plantas bioindicadoras após fitorremediação. Trichilia hirta apresentou maior biomassa quando tratada com atrazina e sulfentrazone. Os herbicidas diminuíram a atividade microbiana em Triplaris americana e não afetaram os indicadores microbiológicos de Myrsine gardneriana, Schizolobium parahyba e Toona ciliata. Menos plantas bioindicadoras sobreviveram no solo com Triplaris americana e sulfentrazone. Os indicadores microbiológicos foram influenciados de formas distintas entre as espécies pela presença dos herbicidas na rizosfera.

Normalized difference vegetation index for desiccation evaluation with glyphosate + 2, 4-D in magnetized spray solution / Índice de vegetação por diferença normalizada para avaliação de dessecação com glyphosate + 2, 4-D em calda magnetizada

Water magnetization and geoprocessing are increasingly utilized tools in weed management. Our objective was to study the influence of water magnetization on herbicide efficiency and to verify whether there is a relationship between control scores and the normalized difference vegetation index (NDVI). In the laboratory experiment, water was subjected to magnetization and evaluated with respect to four characteristics. In the field experiment, plots of Brachiaria grass were subjected to treatments in a factorial scheme (6 × 2 + 1). Six herbicidal factors (doses of glyphosate and glyphosate + 2,4-D) and the magnetization or absence of magnetization of the spray solution were evaluated and compared against the control treatment (without spraying). Weed control assessments were carried out six times. Images were obtained using an embedded multispectral camera to determine the NDVI values. Data related to water characteristics were analyzed using the t test. Weed control and NDVI data were subjected to analysis of variance and are presented in regression graphs. Dispersion analysis of NDVI data was performed according to the control scores. The magnetization process decreased the pH of the water and increased the surface tension, but it did not influence the control scores or the NDVI. As the glyphosate dose was increased, the control scores were higher and the NDVI values were lower. Magnetized water did not affect the biological efficiency of the herbicides, and there was a strong correlation between the control scores and the NDVI values.

A magnetização da água e o geoprocessamento são ferramentas cada vez mais utilizadas no manejo de ervas daninhas. Nosso objetivo foi estudar a influência da magnetização da água na eficiência do herbicida e verificar se existe uma relação entre os escores de controle e o índice de vegetação por diferença normalizada (NDVI). No experimento de laboratório, a água foi submetida à magnetização e avaliada em relação a quatro características. No experimento de campo, parcelas de capim-braquiária foram submetidas a tratamentos em esquema fatorial (6 × 2 + 1). Seis fatores herbicidas (doses de glyphosate e glyphosate + 2,4-D) e a magnetização ou ausência de magnetização da calda foram avaliados e comparados com o tratamento controle (sem pulverização). Avaliações de controle de plantas daninhas foram realizadas seis vezes. As imagens foram obtidas usando uma câmera multiespectral incorporada para determinar os valores de NDVI. Os dados relacionados às características da água foram analisados por meio do teste t. O controle de plantas daninhas e os dados de NDVI foram submetidos à análise de variância e são apresentados em gráficos de regressão. A análise de dispersão dos dados NDVI foi realizada de acordo com os escores de controle. O processo de magnetização diminuiu o pH da água e aumentou a tensão superficial, mas não influenciou nos escores de controle ou no NDVI. Conforme a dose de glyphosate foi aumentada, os escores de controle foram maiores e os valores de NDVI foram menores. A água magnetizada não afetou a eficiência biológica dos herbicidas, e houve uma forte correlação entre os escores de controle e os valores de NDVI.

Epidemiological characteristics of pesticide poisoning in Chengdu City from 2012 to 2021 / 中华劳动卫生职业病杂志

Objective: To explore the present situation and epidemiological characteristics of pesticide poisoning in Chengdu City from 2012 to 2021, and to provide scientific evidence for further prevention and control. Methods: In January 2022, the pesticide poisoning report cards of Chengdu City from 2012 to 2021 were collected from the China Disease Control and Prevention Information System. The data of the report card was reorganized and the distribution characteristics of pesticide poisoning such as time, region, gender, age and pesticide types were analyzed. Results: 14326 cases of pesticide poisoning were reported in Chengdu City from 2012 to 2021, 651 deaths, and the fatality rate was 4.54%. The cases of productive pesticide poisoning and unproductive pesticide poisoning were 504 and 13822, respectively. The fatality rates of productive and unproductive pesticide poisoning were 1.39% and 4.66%, which were significant different (χ(2)=11.99, P=0.001). The highest reported cases of pesticide poisoning was in 2013 (1779) and the lowest in 2021 (1047). The number of reported cases showed a downward trend year by year (t=-12.30, P<0.001), and the fatality rates also showed a downward trend year by year (χ(2)(trend)=25.48, P<0.001). The fluctuation range of unproductive pesticide poisoning cases in each month of the year was small, and the productive pesticide poisoning mainly occurred from May to August. The regions with the largest number of reported poisoning cases were Pengzhou (1620), Jianyang (1393), Jintang (1266) and Qionglai (1158). The high incidence of poisoning was among 25-54 years old (50.21%, 7193/14326). The fatality rate in the age group 75-96 years old was the highest (8.98%, 95/1058), and the fatality rates increased gradually with age (χ(2)(trend)=186.03, P<0.001). The pesticides causing poisoning were mainly insecticide (43.86%, 6284/14326) and herbicides (35.75%, 5121/14326). Herbicides paraquat had the highest fatality rate (9.54%, 286/2998) . Conclusion: Pesticide poisoning in Chengdu City is mainly unproductive poisoning. Health education should be carried out for key areas and people, and the control of highly toxic pesticides such as insecticide and herbicides should be strengthened.

A case of delayed peripheral neuropathy caused by diquat poisoning / 中华劳动卫生职业病杂志

Diquat is a kind of conductive contact-killing herbicides. The damage of central nervous system is relatively common, but the peripheral neuropathy caused by diquat has not been reported yet. In September 2021, we treated a patient with diquat poisoning. During the hospitalization, the patient was diagnosed with peripheral neuropathy. Therapy for peripheral nerve injury was given on the basis of conventional treatment of poisoning. The patient was discharged after his condition was stable. The follow-up showed that the peripheral neuropathy of patient was better than before. According to the condition of this patient, it is suggested that we should not only protect the function of gastrointestinal tract, liver, kidney, and central nervous system early, but should also pay attention to the damage of peripheral nervous system in clinical work. We should intervene earlier to improve the prognosis of patients.

Consultorio de Salud Ambiental en un Hospital Privado de Comunidad de la Ciudad de Buenos Aires / Environmental Health consulting office in a Private Community Hospital of the Buenos Aires City

En los últimos años surge el concepto de Una Sola Salud que reconoce la interdependencia sistémica al observar que los cambios en la salud humana se expresan de manera sincrónica e indivisible de la salud del ambiente. Nuevas enfermedades y daños crónicos inespecíficos ocurren a la par de la pérdida de biodiversidad y vitalidad. En las últimas décadas venimos observando el surgimiento de "adaptaciones sistémicas" que requieren un abordaje desde la clínica y la toxicología a nivel individual y desde la epidemiología de la complejidad a nivel poblacional. Luego de un largo recorrido de investigaciones, el Hospital Italiano formalizó el consultorio de Salud Ambiental con la intención de brindar respuesta a la demanda de pacientes que atribuyen síntomas y signos a la polución ambiental. (AU)

In recent years, the concept of One Health has emerged, recognizing the systemic interdependence and the changes in human health that are expressed synchronously and indivisible from the environment. New diseases and nonspecific chronic damage are occuring in parallel with the loss of biodiversity and vitality.In recent decades we have observed the appearance of "systemic adaptations" that require a clinical and toxicological approach at the individual level, and address the population level from an epidemiological and complexity science paradigm. After many years of research, the Hospital Italiano de Buenos Aires formalized the Environmental Health consulting office and the measurement of glyphosate levels, giving answer to the demand of patients who associate their signs and symptoms to environmental pollution. (AU)

Características sociodemográficas y clínicas relacionadas con la condición final de pacientes intoxicados por paraquat en un hospital del suroccidente de Colombia / Sociodemographic and clinical characteristics related to the final condition of patients intoxicated by paraquat in a hospital in southwestern Colombia

Introducción. El herbicida paraquat constituye la primera causa de decesos por intoxicaciones en distintos países. Objetivo. Relacionar las características sociodemográficas y clínicas con la condición final de pacientes intoxicados por paraquat atendidos en un hospital del suroccidente de Colombia. Materiales y métodos. En este estudio observacional, descriptivo, analítico, transversal y retrospectivo, se revisaron las historias clínicas de pacientes atendidos por intoxicación con paraquat en una institución de tercer nivel de complejidad en Pasto (Colombia) entre el 2013 y el 2018. Se recolectó la información sobre la condición final (vivo o fallecido) de cada paciente, así como los datos sociodemográficos, clínicos y de los exámenes paraclínicos. Se establecieron comparaciones por grupos y se diseñó un modelo de regresión logística binaria. Resultados. Se filtró la información de 299 registros y se analizaron finalmente 160 casos. Las características relacionadas con la condición final de los pacientes fueron el tiempo de estancia (OR=0,124; IC95% 0,03-0,6; p=0,009), la frecuencia cardiaca (OR=35,65; IC95% 1,44-884,78; p=0,029) y la creatinina inicial (OR=1,73; IC95% 1,23-2,44; p=0,002). Conclusiones. La proporción de la letalidad fue mayor entre los pacientes con estancia hospitalaria corta, taquicardia y elevación de la concentración sérica de creatinina al ingreso. Este reporte puede ser útil como fundamento de una escala de gravedad para detectar a los pacientes con resultados adversos en la fase temprana para que puedan recibir una intervención oportuna.

Introduction: Paraquat is an agrochemical that constitutes the first cause of death by poisoning in different countries. Objective: To relate sociodemographic and clinical characteristics with the final condition of patients intoxicated by paraquat in a hospital in southwestern Colombia. Materials and methods: This was an observational, descriptive, analytical, crosssectional, and retrospective study. We reviewed the medical records of patients diagnosed with paraquat poisoning at a level III hospital in Pasto, Colombia, from 2013 to 2018. We collected the data regarding their final condition (alive or deceased) and their sociodemographic, clinical, and paraclinical information. We established group comparisons and designed a binary logistic regression model. Results: We reviewed 299 records and, after the exclusion, we analyzed 160 cases. The characteristics related to the final condition of the patients were length of stay (OR = 0.124; 95% CI: 0.03-0.6; p = 0.009), heart rate (OR = 35.65; 95% CI: 1.44-884.78; p = 0.029), and initial creatinine (OR = 1.73; 95% CI: 1.23-2.44; p = 0.002). Conclusion: The proportion of case fatality was higher in patients with short hospital stay times and elevated heart rates and admission creatinine levels. This report may be useful as a rationale for the creation of a severity scale for the early detection of patients with adverse outcomes and their timely treatment.

Hallazgos en imágenes de tórax en una intoxicación aguda con paraquat: reporte de un caso / Findings on thorax images in acute paraquat poisoning: case report

Resumen El Paraquat es un herbicida ampliamente utilizado para el control de las malezas en Chile. Su ingesta determina una alta probabilidad de mortalidad dado su inherente toxicidad mediante la producción de radicales libres, que afectan a múltiples órganos, principalmente los pulmones; a esto se suma la falta de un tratamiento efectivo. Se presenta el caso clínico de un hombre de 18 años que en un intento suicida consume 50 mL de paraquat (200 g/L), con desenlace fatal. La presentación clínica depende la cantidad de Paraquat ingerida y los hallazgos radiológicos descritos varían según la temporalidad del cuadro e, inclusive, podrían determinar el pronóstico.

Paraquat is an herbicide widely used for weed control in Chile. Its intake determines a high probability of mortality because of its inherent toxicity through the production of free radicals. Multiple organs are affected, mainly the lungs; to this is added the lack of effective treatment. We present the clinical case of an 18-year-old man who in a suicidal attempt swallows 50 mL of paraquat (200 g/L), with a fatal outcome. The clinical presentation depends on the amount of Paraquat ingested. Radiological findings described vary according to the temporality of the condition and could even determine the prognosis

Deposition of diquat with different spray tips, efficiency on common water hyacinth, and effect on water quality

Eichhornia crassipes, known as common water hyacinth, has a high growth rate and produces large amounts of biomass when there are imbalances in water bodies, making it one of the worst aquatic weeds in the world. A study was carried out under small water reservoir field conditions to evaluate the herbicide diquat (960 g ha−1) in controlling this species, at the adult stage development. Four spray tips (AI 11002VS, XR 11002VS and, TXVK-8 with spray volume of 200 L ha−1 and XR 11003VS with 400 L ha−1) were tested. Spraying was performed using a CO2-pressurized sprayer under constant pressure attached to a boat. Plant control was visually evaluated at 1, 3, 7, 11, 14, 21, 29, 60, 87, and 98 days after herbicide application and dry matter accumulation was determined at the end of the experimental period, as well as the spray solution deposition in the application area and water physical and chemical quality. The herbicide diquat was efficient in controlling E. crassipes plants at the dose applied and in development stage of the studied plants, regardless of the type of spray tip at the end of the evaluations. At the beginning of evaluations, the spray tip XR 11002VS was the least effectivity in controlling water hyacinth plants. Spray solution losses were high in all tips tested for control of E. crassipes plants, and the spray tips AI 11002VS and XR 11003VS provided the lowest losses during spraying. No water physical or chemical characteristics were negatively affected by diquat application.

Herbicide efficacy in the fall management of Richardia brasiliensis, Commelina benghalensis, Conyza sumatrensis AND Digitaria insularis

Other herbicides, alone or in combination with glyphosate, may be effective in controlling Richardia brasiliensis, Commelina benghalensis, Conyza sumatrensis e Digitaria insularis. Therefore, the aim of this study was to evaluate the efficacy of herbicides, alone or in combination, in the control of these weeds in the off-season. Three composite experiments were conducted by applying herbicides, alone or in combinations. Experiments 1 and 2 were conducted in Palotina, State of Paraná (PR), Brazil. Experiment 3 in Iporã, PR, Brazil. The three during fall 2017 in fallow areas after soybean harvest. The experiment was a randomized complete block design with 4 replications and weed control at 7, 14, 21, 28, 35, and 42 days after application (DAA). The control of R. brasiliensis and C. benghalensis was evaluated in the three experiments, the control of C. sumatrensis, in experiments 1 and 2, while the control of D. insularis was evaluated only in experiment 3. Data were subjected to analysis of variance and F-test (p < 0.05). The treatment means values of experiments 1 and 2 were compared by Tukey's test (p < 0.05), and the treatment mean values of experiment 3 were grouped by the Scott and Knott test (p < 0.05). Some herbicide combinations were effective in controlling R. brasiliensis, C. benghalensis, in a single or sequential application. Herbicide combinations were effective in controlling C. sumatrensis with sequential application. Herbicide combinations in a single application did not provide satisfactory final control (≥ 80%) for D. insularis.

Effect of different herbicides on Bidens pilosa and Euphorbia heterophylla biotypes resistant to ALS inhibitors

Select herbicides with different mechanism of action is a satisfactory option for resistant weed control. Then, the present work aimed to study the efficiency of different herbicides and their mixtures on Bidens pilosa (blackjack) and Euphorbia heterophylla (wild poinsettia) biotypes, resistant to ALS herbicides in two development stages. The trials we arranged in a completely randomized design with four replications. The treatments tested were (g a.i/a.e ha-1): imazethapyr at 70 and 140 (WG formulation) + 1.0% Assist; imazethapyr at 57.6 and 72 (SL formulation) + 1.0% Assist; imazapic + imazethapyr at 56 and 70 + 1.0% Assist; glyphosate + imazethapyr (596); saflufenacil + glyphosate at 35 + 720 + 0.5% Dash in tank mix, glyphosate at 720 and, a control without herbicide application. Control efficiency was evaluated, as well as dry matter accumulation at the end of the studies. Plants of both species were more susceptible to herbicides at the early stage of development (2 to 4 leaves). The treatments with saflufenacil + glyphosate, (imazethapyr + glyphosate) and glyphosate promoted the best controls, regardless of the species studied and the application stage. The mixture with saflufenacil provided the highest control speed, and the mixture (imazethapyr + glyphosate) was less efficient among three excellent treatments when applied to plants in the 4-6 leaf stage. The treatments (imazethapyr, in both formulations) and (imazethapyr + imazapic) were ineffective in controlling the studied biotypes, regardless of dose and developmental stage studied.

Effects of the pesticides chlorpyriphos, metsulfuron-methyl, and thiamethoxam on ant communities in wheat crop

Ants are important components of food webs in several ecosystems. In anthropic areas, they can be used as bioindicators of the environmental impacts caused by many factors or in the evaluation of the dynamics of the recovery of an area after a certain disturbance. In this context, ants can be used as bioindicators in studies on the evaluation of environmental disturbances caused by pesticide use. Thus, the present work investigated the environmental impacts caused by the application of the insecticides chlorpyriphos and thiamethoxam and the herbicide metsulfuron-methyl in the community of ants in wheat crop (Triticum aestivum L.). The data were collected by pitfall traps and Berlese funnels. A Principal Response Curve was used for a relative abundance analysis. In addition, diversity index and richness were calculated for ant communities. The presence of six families, 11 tribes, 15 genera, and 19 morphospecies of ants belonging to the guilds of fungivorous, omnivorous, and predaceous ants were observed in the soil of the wheat crop. The insecticides chlorpyriphos and thiamethoxam reduced the richness, diversity, and relative abundance of ants of all the guilds on the surface and inside the soil. The effect of the herbicide metsulfuron-methyl on the community of ants was lower than the impact of the insecticides on these insects.