Nano-enabled agrochemicals: mitigating heavy metal toxicity and enhancing crop adaptability for sustainable crop production.

The primary factors that restrict agricultural productivity and jeopardize human and food safety are heavy metals (HMs), including arsenic, cadmium, lead, and aluminum, which adversely impact crop yields and quality. Plants, in their adaptability, proactively engage in a multitude of intricate processes to counteract the impacts of HM toxicity. These processes orchestrate profound transformations at biomolecular levels, showing the plant's ability to adapt and thrive in adversity. In the past few decades, HM stress tolerance in crops has been successfully addressed through a combination of traditional breeding techniques, cutting-edge genetic engineering methods, and the strategic implementation of marker-dependent breeding approaches. Given the remarkable progress achieved in this domain, it has become imperative to adopt integrated methods that mitigate potential risks and impacts arising from environmental contamination on yields, which is crucial as we endeavor to forge ahead with the establishment of enduring agricultural systems. In this manner, nanotechnology has emerged as a viable field in agricultural sciences. The potential applications are extensive, encompassing the regulation of environmental stressors like toxic metals, improving the efficiency of nutrient consumption and alleviating climate change effects. Integrating nanotechnology and nanomaterials in agrochemicals has successfully mitigated the drawbacks associated with traditional agrochemicals, including challenges like organic solvent pollution, susceptibility to photolysis, and restricted bioavailability. Numerous studies clearly show the immense potential of nanomaterials and nanofertilizers in tackling the acute crisis of HM toxicity in crop production. This review seeks to delve into using NPs as agrochemicals to effectively mitigate HM toxicity and enhance crop resilience, thereby fostering an environmentally friendly and economically viable approach toward sustainable agricultural advancement in the foreseeable future.

Integrated predictive QSAR, Read Across, and q-RASAR analysis for diverse agrochemical phytotoxicity in oat and corn: A consensus-based approach for risk assessment and prioritization.

In the modern fast-paced lifestyle, time-efficient and nutritionally rich foods like corn and oat have gained popularity for their amino acids and antioxidant contents. The increasing demand for these cereals necessitates higher production which leads to dependency on agrochemicals, which can pose health risks through residual present in the plant products. To first report the phytotoxicity for corn and oat, our study employs QSAR, quantitative Read-Across and quantitative RASAR (q-RASAR). All developed QSAR and q-RASAR models were equally robust (R2 = 0.680-0.762, Q2Loo = 0.593-0.693, Q2F1 = 0.680-0.860) and find their superiority in either oat or corn model, respectively, based on MAE criteria. AD and PRI had been performed which confirm the reliability and predictability of the models. The mechanistic interpretation reveals that the symmetrical arrangement of electronegative atoms and polar groups directly influences the toxicity of compounds. The final phytotoxicity and prioritization are performed by the consensus approach which results into selection of 15 most toxic compounds for both species.

Architecture and potential roles of a delta-class glutathione S-transferase in protecting honey bee from agrochemicals.

The European honey bee, Apis mellifera, serves as the principle managed pollinator species globally. In recent decades, honey bee populations have been facing serious health threats from combined biotic and abiotic stressors, including diseases, limited nutrition, and agrochemical exposure. Understanding the molecular mechanisms underlying xenobiotic adaptation of A. mellifera is critical, considering its extensive exposure to phytochemicals and agrochemicals present in the environment. In this study, we conducted a comprehensive structural and functional characterization of AmGSTD1, a delta class glutathione S-transferase (GST), to unravel its roles in agrochemical detoxification and antioxidative stress responses. We determined the 3-dimensional (3D) structure of a honey bee GST using protein crystallography for the first time, providing new insights into its molecular structure. Our investigations revealed that AmGSTD1 metabolizes model substrates, including 1-chloro-2,4-dinitrobenzene (CDNB), p-nitrophenyl acetate (PNA), phenylethyl isothiocyanate (PEITC), propyl isothiocyanate (PITC), and the oxidation byproduct 4-hydroxynonenal (HNE). Moreover, we discovered that AmGSTD1 exhibits binding affinity with the fluorophore 8-Anilinonaphthalene-1-sulfonic acid (ANS), which can be inhibited with various herbicides, fungicides, insecticides, and their metabolites. These findings highlight the potential contribution of AmGSTD1 in safeguarding honey bee health against various agrochemicals, while also mitigating oxidative stress resulting from exposure to these substances.

Retrospective evaluation of the eye irritation potential of agrochemical formulations.

Multiple in vitro eye irritation methods have been developed and adopted as OECD health effects test guidelines. However, for predicting the ocular irritation/damage potential of agrochemical formulations there is an applicability domain knowledge gap for most of the methods. To overcome this gap, a retrospective evaluation of 192 agrochemical formulations with in vivo (OECD TG 405) and in vitro (OECD TG 437, 438, and/or 492) data was conducted to determine if the in vitro methods could accurately assign United Nations Globally Harmonized System for Classification and Labelling of Chemicals (GHS) eye irritation hazard classifications. In addition, for each formulation the eye irritation classification was derived from the classification of the contained hazardous ingredients and their respective concentration in the product using the GHS concentration threshold (CT) approach. The results herein suggest that the three in vitro methods and the GHS CT approach were highly predictive of formulations that would not require GHS classification for eye irritation. Given most agrochemical formulations fall into this category, methods that accurately identify non-classified agrochemical formulations could significantly reduce the use of animals for this endpoint.

Use of in silico and in vitro methods as a potential new approach methodologies (NAMs) for (photo)mutagenicity and phototoxicity risk assessment of agrochemicals.

The increased use of agrochemicals raises concerns about environmental, animal, and mainly human toxicology. The development of New Approach Methodologies (NAMs) for toxicological risk assessment including new in vitro tests and in silico protocols is encouraged. Although agrochemical mutagenicity testing is well established, a complementary alternative approach may contribute to increasing reliability, with the consequent reduction of false-positive results that lead to unnecessary use of animals in follow-up in vivo testing. Additionally, it is unreasonable to underestimate the phototoxic effects of an accidental dermal exposure to agrochemicals during agricultural work or domestic application in the absence of adequate personal protection equipment, especially in terms of photomutagenicity. In this scenario, we addressed the integration of in vitro and in silico techniques as NAMs to assess the mutagenic and phototoxic potential of agrochemicals. In the present study we used the yno1 S. cerevisiae strain as a biomodel for in vitro assessment of agrochemical mutagenicity, both in the absence and in the presence of simulated sunlight. In parallel, in silico predictions were performed using a combination of expert rule-based and statistical-based models to assess gene mutations and phototoxicity. None of the tested agrochemicals showed mutagenic potential in the two proposed approaches. The Gly and 2,4D herbicides were photomutagenic in the in vitro yeast test despite the negative in silico prediction of phototoxicity. Herein, we demonstrated a novel experimental approach combining both in silico and in vitro experiments to address the complementary investigation of the phototoxicity and (photo)mutagenicity of agrochemicals. These findings shed light on the importance of investigating and reconsidering the photosafety assessment of these products, using not only photocytotoxicity assays but also photomutagenicity assays, which should be encouraged.

Impairment of visual and neurologic functions associated with agrochemical use.

To determine whether exposure to occupational levels of agrochemicals is associated with a range of low- (contrast and colour) and higher-level visual functions, particularly the detection of global form and motion coherence. We compared the performance of workers exposed to occupational levels of pesticides and non-exposed individuals on visual tasks that measured colour discrimination (Farnsworth Munsell 100 and Lanthony D15 desaturated) and the contrast sensitivity function (1-16 cpd). Global form and motion detection thresholds were measured using Glass-pattern and global dot motion stimuli. Neurotoxicity symptoms and biological markers associated with pesticide exposure were quantified using the Q16 modified questionnaire and via tests for levels of acetylcholinesterase in blood and substance P from the tear film, respectively. Workers exposed to pesticides had significantly more neurotoxic symptoms than non-exposed workers. No significant difference between groups for acetylcholinesterase levels was found, but there was a significant group difference in Substance P. The exposed group also had significantly poorer contrast sensitivity, colour discrimination and higher coherence detection thresholds for global form and motion perception. Exposure to occupational levels of agrochemicals in workers with signs of neurotoxicity is associated with low and high visual perception deficits.

An alternative approach to assess ecotoxicological effects of agrochemical combinations used in Brazilian aquaculture farms.

Agrochemicals used for treating and preventing aquaculture diseases are usually present in combination with other compounds, and the toxicity resulting from their chemical interactions presents an important reason to assess the ecotoxicity of compound mixtures in view to better understanding the joint action of chemicals and avoiding their environmental impacts. In this study, we evaluated the acute aquatic ecotoxicity of several compounds used in Brazilian fish farming (Oxytetracycline [OXT], Trichlorfon [TRC], and BioFish® [BIO]), both individually and in binary and ternary mixtures. Initial test concentrations were prepared according to the recommended concentrations for aquaculture application, and from these, a geometric dilution series was tested on two important fresh water quality indicator species, the microcrustacean Daphnia magna and the bacterium Aliivibrio fischeri. At the recommended pond application rate, TRC and BIO applied individually showed toxicity to the tested organisms in terms of the lowest-observed-effect concentration (LOEC), and D. magna was always more sensitive than A. fischeri. For the two test organisms, the results obtained with the binary mixtures showed that the TRC and BIO mixture was more toxic than TRC and OXT, which in turn was more toxic than OXT and BIO. The toxicity from all agrochemicals in the ternary mixture was more than that of the agrochemical combinations in the binary mixtures. Given the results presented in this study, it is evident that the mode of action and availability of the tested compounds undergo changes that increase toxicity when they are present in combination, and therefore, aquaculture wastewater treatment should be adopted to ensure decontamination of agrochemical residues.

A novel laboratory method for simulating pollinator exposure to agrochemical-laden particulate matter.

Environmental transport and deposition of particulate matter (PM) associated with toxic chemicals has begun to receive attention as a source of risk to pollinators. For example, dust arising from manipulations of insecticide-treated seed has potential to exert toxic effects among non-target insects. Similarly, synthetic steroid growth promoters, antibiotics and multiple insecticides and parasiticides detected in fugitive beef cattle feedyard PM may also negatively impact pollinators since many of these chemicals have been detected on wildflowers and pollinators collected near beef cattle feedyards. Therefore, there is a need to assess risk to pollinators posed by deposition of agrochemical-laden PM, both in the field and the laboratory. Unfortunately, established laboratory methods for simulating PM exposure or toxicity associated with contaminated PM are few and highly situation-specific. Herein we describe development and use of a PM circulation system that can be employed to evaluate toxicity of agrochemical-contaminated PM in the laboratory under controlled conditions. Two model organisms (honeybees (Apis mellifera) and mason bees (Osmia lignaria)) were exposed to agrochemical-free PM in the circulator system, and post-exposure mortality was compared with controls. No significant differences in mortality between exposed and control bees were observed. Next, honeybees and mason bees were exposed to PM spiked with an insecticide known to exert toxic effects to pollinators (thiamethoxam). Bees experienced significantly higher mortality when exposed to thiamethoxam-laden PM at environmentally relevant concentrations as compared to bees exposed to agrochemical-free PM. These results confirm the validity of these methods for use in controlled laboratory PM toxicity tests and offer a source of positive and negative control groups for laboratory and field experiments examining exposure of pollinators to potentially toxic agrochemical-laden PM. This method facilitates generation of more realistic toxicity data than standard contact toxicity tests when pollinator exposure scenarios involve particulate-based agrochemicals or other toxic chemicals.

Challenges and opportunities for overcoming dog use in agrochemical evaluation and registration.

Progress in developing new tools, assays, and approaches to assess human hazard and health risk provides an opportunity to re-evaluate the necessity of dog studies for the safety evaluation of agrochemicals. A workshop was held where partic­ipants discussed the strengths and limitations of past use of dogs for pesticide evaluations and registrations. Opportunities were identified to support alternative approaches to answer human safety questions without performing the required 90-day dog study. Development of a decision tree for determining when the dog study might not be necessary to inform pesticide safety and risk assessment was proposed. Such a process will require global regulatory authority participation to lead to its acceptance. The identification of unique effects in dogs that are not identified in rodents will need further evaluation and determination of their relevance to humans. The establishment of in vitro and in silico approaches that can provide critical data on relative species sensitivity and human relevance will be an important tool to advance the decision process. Promising novel tools including in vitro comparative metabolism studies, in silico models, and high-throughput assays able to identify metabolites and mechanisms of action leading to development of adverse outcome pathways will need further development. To replace or eliminate the 90-day dog study, a collaborative, multidisciplinary, international effort that transcends organi­zations and regulatory agencies will be needed in order to develop guidance on when the study would not be necessary for human safety and risk assessment.

The quest for metabolic biomarkers of agrochemicals exposure via in vitro studies and suspect screening.

Numerous agrochemicals, including pesticides and herbicides, are applied in modern agriculture, resulting in concerns for the ecosystem and human safety as humans are easily exposed to these compounds. Many agrochemicals, and their transformation products or metabolites, have shown toxicity in in vitro and in vivo studies. However, given the rapid development of novel agrochemicals, for many there is no information about their effects nor about metabolic transformations when ingested by humans. Tracing biomarkers may be the best method for assessing the impacts of agrochemicals. A combination of in vitro metabolism study and suspect screening of human samples (e.g., urine, blood) can be utilized to efficiently find biomarkers for agrochemical exposure. In the work reported here, we determined the in vitro metabolic profiling of six prioritized pesticides and synergists, namely boscalid, carbendazim, piperonyl butoxide, spiroxamine, dimethomorph and fludioxonil, in human liver microsomes. 17 major metabolites were structurally elucidated by high resolution mass spectrometry (HRMS). Major metabolic transformation processes (e.g., hydroxylation, demethylation and oxidation) were proposed for each pesticide. Individual in silico toxicity assessments showed that some metabolites had the same or even enhanced toxicity compared to parent compounds. Information about these metabolites obtained from HRMS was used for suspect screening in human activities related samples. Carbendazim and a metabolite of fludioxonil were identified in wastewater and laboratory urine samples, respectively. Our findings provide concrete evidence for the use of in vitro metabolites as biomarkers in biomonitoring studies of potential exposure to toxic chemicals.

Towards achieving a modern science-based paradigm for agrochemical carcinogenicity assessment.

The rodent cancer bioassay has been the standard approach to fulfill regulatory requirements for assessing human carcinogenic potential of agrochemicals, food additives, industrial chemicals, and pharmaceuticals. Decades of research have described the limitations of the rodent cancer bioassay leading to international initiatives to seek alternatives and establish approaches that modernize carcinogenicity assessment. Biologically relevant approaches can provide mechanistic information and increased efficiency for evaluating hazard and risk of chemical carcinogenicity to humans. The application of human-relevant mechanistic understanding to support new approaches to carcinogenicity assessment will be invaluable for regulatory decision-making. The present work outlines the challenges and opportunities that authorities should consider as they come together to build a roadmap that leads to global acceptance and incorporation of fit-for-purpose, scientifically defensible new approaches for human-relevant carcinogenicity assessment of agrochemicals.

Chronic consumption of contaminated feed with 2 4 dichlorophenoxyacetic acid (2 4 D) herbicide in rodents: effects on male reproductive health / Consumo crônico de ração contaminada com herbicida ácido 2 4 di clorofenoxiacético (2 4 D) em roedores: efeitos na saúde reprodutiva masculina

Introduction: The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) is one of the most widely used pesticides in the world. There is evidence that this herbicide can induce deleterious effects in non-target organisms, including impairment of reproduction function. Objective: The aim of this study was to evaluate the reproductive effects of the chronic consumption of contaminated feed with 2,4-D in rats using food environmental spraying simulation. Methods: Animals orally exposed received nebulized chow with 2,4-D solution in different concentrations for 180 days: 0 (control - CG), 20.69 (LCG), 34.63 (MCG), or 51.66 ppm day−1 (HCG). Results: Sperm quality was impaired to 2,4-D. The percentage of sperm with progressive movement, number of sperm in the testis and daily sperm production were decreased in all exposed groups to the herbicide compared to CG. Sperm counts in the caput/corpus and cauda epididymis were reduced in MCG and HCG, and sperm transit time was delayed in the epididymis of LCG. There was a negative impact on sperm morphology and plasma membrane integrity in MCG and HCG, respectively. Germ cell exfoliation within the lumen of the seminiferous tubules and epithelial vacuolization in epididymis were found in the HCG. Conclusion: This is the first study to describe the negative impact on male reproductive morphophysiology after chronic exposure to 2,4-D using food nebulization in environmentally relevant concentrations, based on agronomic use of the herbicide. The reproductive injuries identified raise concerns about the impacts of wide population exposure to 2,4-D (AU).

Introdução: O herbicida 2,4- ácido diclorofenoxiacético (2,4-D) é um dos agrotóxicos mais utilizados no mundo. Há evidências de que este herbicida pode induzir efeitos deletérios em organismos não-alvo, incluindo prejuízo na função reprodutiva. Objetivo: O objetivo deste estudo foi avaliar os efeitos reprodutivos do consumo crônico de ração contaminada com 2,4-D em ratos, utilizando simulação de pulverização ambiental de alimentos. Métodos: Animais expostos oralmente receberam ração nebulizada com solução de 2,4-D em diferentes concentrações por 180 dias: 0 (controle - GC), 20,69 (LCG), 34,63 (MCG) ou 51,66 ppm dia−1 (HCG). Resultados: A qualidade espermática foi prejudicada pelo 2,4-D. A porcentagem de espermatozoides com movimento progressivo, número de espermatozoides no testículo e produção diária de espermatozoides foram menores em todos os grupos expostos ao herbicida, quando comparados ao GC. A contagem de espermatozoides na cabeça/corpo e cauda do epidídimo foi reduzida em MCG e HCG, e o tempo de trânsito espermático atrasou no epidídimo em LCG. Houve impacto negativo na morfologia espermática e na integridade da membrana plasmática em MCG e HCG, respectivamente. Esfoliação de células germinativas no lúmen dos túbulos seminíferos e vacuolização epitelial no epidídimo foram encontradas em HCG. Conclusão: Este é o primeiro estudo a descrever o impacto negativo na morfofisiologia reprodutiva masculina após exposição crônica ao 2,4-D, utilizando nebulização de alimentos em concentrações ambientalmente relevantes, com base no uso agronômico do herbicida. As lesões reprodutivas identificadas levantam preocupações sobre os impactos da ampla exposição da população ao 2,4-D (AU).

Comercialização de agrotóxicos e desfechos de saúde no Estado do Paraná: uma associação não linear / Marketing of Pesticides and Health Outcomes in the State of Paraná: A Nonlinear Association

Resumo Este estudo ecológico teve por objetivo analisar a associação entre a quantidade de comercialização de agrotóxicos e alguns agravos e causas de mortalidade no estado do Paraná no período de 2013 a 2017. Desta forma, realizou-se um comparativo entre as 22 regiões de saúde, identificando a relação entre a taxa de comercialização de agrotóxicos por habitante com as seguintes variáveis: taxa de intoxicações exógenas relacionadas ao trabalho, taxa de intoxicações exógenas por agrotóxicos relacionadas ao trabalho, taxa de tentativas de suicídio e taxas de mortalidade por neoplasias, malformação congênita e suicídio. Para estes três últimos desfechos de saúde, os modelos não lineares selecionados tiveram seus R-quadrado acima de 0,500. A Regional de Saúde de Cascavel se destacou com mais municípios com altas taxas de comercialização de agrotóxicos e desfechos de saúde, ao contrário da Regional de saúde Metropolitana. Observa-se que o perfil dos municípios que têm maiores taxas dos agravos estudados é rural e com produção majoritariamente de soja, milho, trigo, fumo, pastagens e feijão. Dessa forma, ressalta-se a necessidade de rever o modelo agroalimentar convencional e promover políticas públicas rigorosas para controle dos agrotóxicos, além de prevenção de agravos à saúde, fortalecendo os serviços de Vigilância Epidemiológica.

Abstract This ecological study aimed to analyze the association between the amount of pesticide commercialization and some diseases and causes of mortality in the state of Paraná from 2013 to 2017. In this way, a comparison was made between the 22 health regions, identifying the relationship between the rate of commercialization of pesticides per inhabitant with the following variables: rate of exogenous intoxication related to work, rate of exogenous intoxication by pesticides related to work, rate of suicide attempts and mortality rates from neoplasms, congenital malformation and suicide. For these last three health outcomes, the selected nonlinear models had their R-squared above 0.500. The Cascavel Health Region stood out with more municipalities with high rates of pesticide marketing and health outcomes, unlike the Metropolitan Health Region. It is observed that the profile of the municipalities that have the highest rates of the diseases studied is rural and with production mainly of soy, corn, wheat, tobacco, pastures, and beans. Thus, the need to review the conventional agri-food model and promote rigorous public policies to control pesticides, in addition to preventing health problems, strengthening Epidemiological Surveillance services is highlighted.

Evaluation of genotoxicity and cytotoxicity of inhabitants of Vila Rural Água Viva, Brazil, exposed to agrochemicals using the micronucleus buccal cytome assay.

The aim of this study was to carry out a pilot investigation, using a buccal micronucleus cytome assay, with the population of Vila Rural Água Viva (Francisco Beltrão, Paraná, Brazil), environmentally exposed to agrochemicals. The data shows statistically differences between the control group (not exposed) and the population of Vila Rural regarding the cytotoxicity and mutagenicity. There was no significant change between the average relative frequencies of these data whether divided between smokers and non-smokers, or practitioners of physical activities or not. It was also observed that age or time of exposure to agrochemicals did not show a linear relationship with the average relative frequencies of cytotoxicity and mutagenicity data. The work shows the presence of 2,4-D herbicide in water sample of community, then it is hoped that the results will assist in guiding the dangers to health and the environment from exposure to agrochemicals.

Combined toxicities of cadmium and five agrochemicals to the larval zebrafish (Danio rerio).

Different pollutants usually co-exist in the natural environment, and the ecological and health risk assessment of agrochemicals needs to be carried out based on the combined toxicological effects of pollutants. To examine the combined toxicity to aquatic organisms, the effects of cadmium (Cd) and five pesticides (acetamiprid, carbendazim, azoxystrobin, chlorpyrifos, and bifenthrin) mixture on zebrafish (Danio rerio) larvae were assessed. The data from the 96-h toxicity test indicated that bifenthrin possessed the highest toxicity to D. rerio with the LC50 value of 0.15 mg L-1, followed by chlorpyrifos (0.36 mg L-1) and azoxystrobin (0.63 mg L-1). Cd (6.84 mg L-1) and carbendazim (8.53 mg L-1) induced the intermediate toxic responses, while acetamiprid (58.39 mg L-1) presented the lowest toxicity to the organisms. Pesticide mixtures containing chlorpyrifos and bifenthrin or acetamiprid and carbendazim showed synergistic impacts on the zebrafish. Besides, two binary combinations of Cd-acetamiprid and Cd-chlorpyrifos also displayed a synergistic effect on D. rerio. Our results offered a better idea of the mixed ecological risk assessment of Cd and different agricultural chemicals to aquatic organisms. Our findings better interpreted how the interaction between Cd and various agrochemicals changed their toxicity to aquatic vertebrates and provided valuable insights into critical impacts on the ecological hazard of their combinations.

A proposed NAM-based tiered phototoxicity testing and human risk assessment framework for agrochemicals.

Phototoxicity testing is required by European regulations for agrochemicals with UV/visible molar extinction/absorption coefficient (MEC) higher than 10 L x mol-1 x cm-1 in the 290-700 nm wavelength range. Furthermore, regulations identify a need of considering human exposure in case of positive results. While in vitro OECD test guidelines are available for hazard characterisation, there is no guidance on how to utilise positive results in human exposure risk assessments. Our goal was to take a first step towards developing a NAM based tiered testing approach and a framework for non-dietary acute human dermal risk assessment for phototoxicity to agrochemicals. The proposed framework can be divided into a few steps: 1) use the OECD updated MEC values of 1000 L x mol-1 x cm-1 as trigger for phototoxicity testing; 2) establish a reference concentration (RfC) from in vitro phototoxicity studies using BMC approach, 3) estimate potential exposure to skin, target organ for phototoxicity, using EFSA exposure models, product specific labels and skin penetration values, and 4) phototoxicity risk assessment; 5) refinement to RfC and/or exposure estimates can be considered. Finally, case studies of a nematicide and an herbicide active substance are provided to illustrate the proposed framework.

Nanotechnology in agriculture: Comparison of the toxicity between conventional and nano-based agrochemicals on non-target aquatic species.

Increased crop production is necessary to keep up with rising food demand. However, conventional agricultural practices and agrochemicals are unable to sustain further increases without serious risk of adverse environmental consequences. The implementation of nanotechnology in agriculture practices has been increasing in recent years and has shown tremendous potential to boost crop production. The rapid growth in development and use of nano-agrochemicals in agriculture will inevitably result in more chemicals reaching water bodies. Some unique properties of nanoformulations may also alter the toxicity of the AI on aquatic organisms when compared to their conventional counterparts. Results from studies on conventional formulations may not properly represent the toxicity of new nanoformulations in the aquatic environment. As a result, current guidelines derived from conventional formulations may not be suitable to regulate those newly developed nanoformulations. Current knowledge on the toxicity of nano-agrochemicals on aquatic organisms is limited, especially in an ecologically relevant setting. This review complies and analyzes 18 primary studies based on 7 criteria to provide a comprehensive analysis of the available toxicity information of nano-agrochemicals and their conventional counterparts on aquatic organisms. Our analysis demonstrates that the overall toxicity of nano-agrochemicals on non-target aquatic species is significantly lower as compared to conventional counterparts. However, further dividing formulations into three categories (organic, bulk and ionic) shows that some nanoformulations can be more toxic when compared to bulk materials but less toxic as compared to ionic formulations while organic nanopesticides do not show a general trend in overall toxicity. Moreover, our analysis reveals the limitations of current studies and provides recommendations for future toxicity studies to ensure the effective and sustainable application of nano-agrochemicals, which will be beneficial to both the agrochemical industry and regulatory agencies alike.

Social and environmental conflicts caused by agrochemical use in Salta, Santiago del Estero and Santa Fe, Argentina. / Conflictividad socio-ambiental por uso de agroquímicos en Salta, Santiago del Estero y Santa Fe, Argentina.

The purpose of this article is to contribute to the understanding and visibility of conflicts and disputes over the use of agrochemicals in the provinces of Santa Fe, Santiago del Estero and Salta, in Argentina. Secondary information sources were gathered and systematized to perform a first contextual analysis of regulatory frameworks, public policies and the emergence of social construction processes related to environmental and health risks. This analysis revolved around three dimensions: a regulatory dimension, a political-institutional dimension, and a territorial-health dimension. In all three jurisdictions, there are specific laws that govern the use of agrochemicals and certain institutionalization intended to implement, control and monitor them. However, similarly to what has happened at the regional and international levels, the study revealed multiple conflict situations and/or events that call environmental and health impacts into question. Agrochemical use policy is shattered into multiple regulations, institutions and levels of competence, a framework in which health and environmental policies are left behind. Despite some progress, there is no official recognition of the health and environmental damage caused by the use of agrochemicals.

El objetivo del artículo es contribuir a la comprensión y visibilización de los conflictos y controversias en torno al uso de agroquímicos en las provincias de Santa Fe, Santiago del Estero y Salta, Argentina. Se relevaron y sistematizaron fuentes de información secundaria, con el fin de llevar adelante un primer análisis contextual de los marcos regulatorios, las políticas públicas y la emergencia de procesos de construcción social de los riesgos ambientales y sanitarios. El análisis fue organizado en torno a tres dimensiones: normativa, político-institucional y territorial-sanitaria. En las tres jurisdicciones existen leyes específicas que regulan el uso de agroquímicos y cierta institucionalidad destinada a su implementación, control y monitoreo. No obstante, y en concordancia con lo ocurrido a nivel regional e internacional, el estudio relevó una multiplicidad de situaciones y/o eventos conflictivos que problematizan los impactos ambientales y sanitarios. La política relativa a la utilización de agroquímicos está fragmentada en múltiples regulaciones, instituciones y escalas de competencias, marco dentro del cual la política sanitaria y ambiental poseen un lugar rezagado. Más allá de ciertos avances, no hay reconocimiento oficial del daño a la salud y el ambiente generado por el uso de agroquímicos.