Environmental exposure to pesticides and risk of thyroid diseases

Pesticide pollution: toxicity, sources and advanced remediation approaches

The Food and Agricultural Organization of the United Nations (FAO) estimates that food production must rise by 70% to meet the demands of an additional 2.3 billion people by 2050. This forecast underscores the persistent reliance on pesticides, making it essential to assess their toxicity and develop effective remediation strategies. Given the widespread utilisation of pesticides, it requires an urgent need to evaluate their toxicity and explore feasible remediation approaches for their removal. Hence, this review provides an overview of the latest information on the presence, distribution, sources, fate, and trends of pesticides in global environmental matrices, emphasizing the ecological and health risks posed by pesticide pollution. Currently, the dominant remediation techniques encompass physical, chemical, and biological methods, yet studies focusing on advanced remediation techniques remain limited. This review critically evaluates both newer and traditional approaches to pesticide removal, offering a descriptive and analytical comparison of various methods. The selection of the appropriate treatment method depends largely on the nature of the pesticide and the effectiveness of the chosen technique. In many cases, technologies such as membrane bioreactors and the fenton process could be integrated with biological technologies to enhance performance and overcome limitations. The study concludes that a hybrid approach combining various remediation strategies offers the most effective and sustainable solution for pesticide removal. Finally, the review underscores the need for further scientific investigation into the most viable technologies while discussing the challenges and prospects of developing safe, reliable, cost-effective, and eco-friendly methods for removing pesticides from the environment.

Variability in strawberry tunnels impacts fruit quality and limits melatonin effects

BACKGROUND

Fluctuations in environmental conditions within fields and crop plant performance can greatly affect production and quality standards. These factors are particularly relevant for producers, who require sustained optimal production to profit from small margins. Fluctuations might be exacerbated at the end of the crop season, where neither of the aforementioned factors are optimal. In the present integrated study, we assess strawberries' nutritional quality and the impact of harvest timing, tunnel conditions and inter-individual variability in a Mediterranean production tunnel divided into blocks, where two harvests were performed 3 weeks apart. In addition, the effects of sprayed melatonin at the end of productive season were also evaluated.

RESULTS

End-season harvesting negatively impacted fruit hydration, antioxidant capacity and ripening-related hormones in strawberry fruits. Additionally, tunnel distribution influenced fruit nutritional quality, with light radiation being the main variable factor disturbing antioxidant contents. Nutrients exhibited high inter-individual plant variability, accounting for 20% variation, and were strongly correlated with fruit hydration and ripening-related phytohormones. Finally, melatonin applications affected neither fruit production, nor nutritional parameters, for which the effects were masked by the intrinsic strawberry variability. Overall, the results underline the limitations of this type of application for field implementation.

CONCLUSION

Fruit quality variation in strawberry fields is explained by environmental and inter-individual variability. Likewise, the implementation of regulatory molecules such as melatonin in field applications relies on crop homogeneity and might have limited applicability in heterogeneous productive systems. Consequently, identifying and reducing microclimate variability in productive fields is paramount for advancing agricultural practices to uphold unwavering standards on fruit quality. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Farming activity and risk of treated thyroid disorders: Insights from the TRACTOR project, a nationwide cohort study

BACKGROUND

Epidemiological data regarding thyroid diseases are lacking, in particular for occupationally exposed populations.

OBJECTIVES

To compare the risk of hypothyroidism and hyperthyroidism between farming activities within the complete population of French farm managers (FMs).

METHODS

Digital health data from retrospective administrative databases, including insurance claims and electronic health/medical records, was employed. This cohort data spanned the entirety of French farm managers (FMs) who had undertaken work at least once from 2002 to 2016. Survival analysis with the time to initial medication reimbursement as timescale was used to examine the association (hazard ratio, HR) between 26 specific farming activities and both treated hypothyroidism and hyperthyroidism. A distinct model was developed for each farming activity, comparing FMs who had never engaged in the specific farming activity between 2002 and 2016 with those who had. All analyses were adjusted for potential confounders (e.g., age), and sensitivity analyses were conducted.

RESULTS

Among 1088561 FMs (mean age 46.6 [SD 14.1]; 31% females), there were 31834 hypothyroidism cases (75% females) and 620 hyperthyroidism cases (67% females), respectively. The highest risks were observed for cattle activities for both hyperthyroidism (HR ranging from 1.75 to 2.42) and hypothyroidism (HR ranging from 1.41 to 1.44). For hypothyroidism, higher risks were also observed for several animal farming activities (pig, poultry, and rabbit), as well as fruit arboriculture (HR = 1.22 [1.14-1.31]). The lowest risks were observed for activities involving horses. Sex differences in the risk of hypothyroidism were observed for eight activities, with the risk being higher for males (HR = 1.09 [1.01-1.20]) than females in viticulture (HR = 0.97 [0.93-1.00]). The risk of hyperthyroidism was two times higher for male dairy farmers than females.

DISCUSSION

Our findings offer a comprehensive overview of thyroid disease risks within the FM community. Thyroid ailments might not stem from a single cause but likely arise from the combined effects of various causal agents and triggering factors (agricultural exposome). Further investigation into distinct farming activities-especially those involving cattle-is essential to pinpoint potential risk factors that could enhance thyroid disease monitoring in agriculture.

Histological evidence of hypothyroidism in mice chronically exposed to conventional farming

Worldwide, disorders of the thyroid gland are a growing concern; such can be caused by exposure to contaminants, including agrochemicals used in conventional agriculture, which act as endocrine disruptors. The purpose of this study is to evaluate whether or not exposure to an environment with conventional agriculture leads to thyroid disruption. Mus musculus were used as bioindicator species, captured in two sites: a farm where conventional agriculture is practiced, and a place without agriculture. Thyroid histomorphometric and morphologic data were analyzed. The impacts of the agricultural environment over the thyroid were revealed, as indications of hypothyroidism were observed in exposed mice: the area and volume of epithelial cells were much lower. Alterations in thyroid histomorphology were also observed: lower follicular sphericity, irregularly delimited epithelium and increased exfoliation into the colloid. These results highlight the need for transition from current conventional agricultural systems towards organic systems.

Thyroid dysfunction caused by exposure to environmental endocrine disruptors and the underlying mechanism: A review

Thyroid disease has been rapidly increasing, but its causes remain unclear. At present, many studies have focused on the relationship between environmental endocrine disruptors (EEDs) and the pathogenesis of thyroid disease. Herein, we summarize such studies exploring the effects of exposure to common EEDs on thyrotoxicosis, finding that EEDs appear to contribute to the pathogenesis of thyroid-related diseases such as thyroid cancer, goiter, thyroiditis, hyperthyroidism, and hypothyroidism. To explore this causative effect in detail, we have analyzed the following three aspects of how EEDs are believed to exert their impacts on the occurrence and development of thyroid disease: (1) damage to the thyroid tissue structure, including disrupted mitochondria and the stratification of thyroid follicular epithelial cells; (2) disruption of thyroid hormone signaling, including thyroid hormone synthesis and secretion disorders, destruction of normal function of the hypothalamus-pituitary-thyroid axis, disturbed estrogen signaling in the body, alterations to the level of thyroid-stimulating hormone, inhibition of the release of thyroglobulin from thyroid cells, and reductions in the levels of sodium iodide co-transporters, thyroid peroxidase, deiodinase, and transthyretin; and (3) molecular mechanisms underlying the disruption of thyroid function, including competitive binding to T3 and T4 receptors, disturbance of the hypothalamic-pituitary-thyroid axis, activation of the ERK and Akt pathways, oxidative stress, regulation of the expression of the proto-oncogene k-Ras, tumor suppressor gene PTEN, and thyroid TSHR gene, and induction of autophagy in thyroid cells. Overall, this article reviews how EEDs can affect the occurrence and development of thyroid disease via multiple routes, thus providing new ideas to intervene for the prevention, diagnosis, treatment, and prognosis of thyroid disease.

Influence of silver nanoparticles on mRNA expression of thyroid hormone-related genes in the thyroid gland and liver of laying hens

The widespread use of silver nanoparticles (AgNPs) in consumer products and animal husbandry raises the need to study their impact on living organisms. This study was conducted on Hy-Line Brown hens at the age of 25 weeks with an average weight of 1.58 kg. Hens for 2 weeks received a solution of 50 nm AgNPs at a concentration of 100 pm (experimental group; n = 6) or a solution in which the nanoparticles were suspended (control group; n = 6). Thyroid hormones (thyroxine - T4, triiodothyronine - T3) were evaluated in the blood plasma and expression profiles of genes involved in thyroid hormone (TH) synthesis (TSHR, NIS, TPO, TG), metabolism (DIO1, DIO2, DIO3) and transport (MCT8, MCT10, LAT1) were determined in the chicken thyroid gland. Furthermore, iodothyronine deiodinase, TH transporter and TH receptor (THRA, THRB) mRNA expressions were evaluated in the livers isolated from the same chickens. AgNPs did not affect serum T4 levels but elevated serum T3 concentration. The results showed that AgNPs increased DIO3 mRNA in the thyroid gland. In turn, in the liver AgNPs administration significantly upregulated DIO2 and downregulated MCT10 mRNA levels. These results indicate that exposure to AgNPs leads to a tissue-specific alternative expression of genes engaged in TH metabolism. Moreover, the mRNA expression of DIO2 in the liver showed a positive correlation with plasma T3 levels. In conclusion, AgNPs may have an impact on TH metabolism by affecting deiodinases and TH transporter MCT10 mRNA expression.

Effect of perinatal exposure to glyphosate and its mixture with 2,4-D and dicamba on rat dam kidney and thyroid function and offspring's health

The increasing use of the herbicide mixture of glyphosate, dicamba and 2-4-D to deal with glyphosate-resistant weeds raises concerns regarding human health and environmental risks. This study aimed to evaluate the effects of developmental exposure to glyphosate and a herbicide mixture containing glyphosate, dicamba and 2-4-D on rat dams' kidney and thyroid function and offspring's health. Pregnant Wistar rats were exposed from day-6 of gestation till weaning to regulatory relevant doses of glyphosate corresponding to the European Union (EU) acceptable daily intake (ADI; 0.5 mg/kg bw/day), and the no-observed-adverse-effect level (NOAEL; 50 mg/kg bw/day), and to a mixture of glyphosate, dicamba and 2,4-D all at the EU ADI (0.5, 0.002 and 0.3 mg/kg bw/day) respectively. After weaning the dams were sacrificed and blood and organs were collected. The pups' health was assessed by measuring viability, gestational and anogenital indices. Perinatal exposure to GLY alone and the herbicide mixture resulted in anti-androgenic effects in male offspring. In dams, exposure to glyphosate resulted in kidney glomerular and tubular dysfunction as well as increased thyroid hormone levels in a dose-dependent manner. Furthermore, exposure to the herbicide mixture resulted in effects similar to those observed with glyphosate at the NOAEL, suggesting at least an additive effect of the herbicide mixture at doses individually considered safe for humans.

Association of polycyclic aromatic hydrocarbon internal exposure and urinary iodine concentration with thyroid volume in children

Thyroid volume was proposed as a factor for malignancy in evaluating thyroid nodules. Previous studies have demonstrated the endocrine disrupting effect of polycyclic aromatic hydrocarbons (PAHs), but studies on the association between internal exposure of PAHs and thyroid volume are still scarce. In this work, we evaluated the association of polycyclic aromatic hydrocarbon internal exposure and urinary iodine concentration with thyroid volume in 590 school-age children without thyroid disease in Guangzhou, China. Urinary hydroxylated polycyclic aromatic hydrocarbons (OH-PAHs), urinary iodine concentrations, and thyroid volumes were measured. The mean concentrations of urinary iodine and ΣOH-PAHs were 271.1 μg/L and 3.27 μg/L, respectively, and the mean thyroid volume was 2.4 mL. The associations of urinary iodine and OH-PAH concentrations with thyroid volume were investigated by multivariable linear regression and the Bayesian kernel machine regression models. Urinary ΣOH-PAHs were observed to be significantly positively associated with thyroid volume in multivariable linear regression models. The increase in each unit in the log-transformed concentration of ΣOH-PAHs caused 3.88% change in thyroid volume. The Bayesian kernel machine regression model demonstrated a positive joint effect of increased urinary ΣOH-PAHs on thyroid volume. Moreover, urinary ΣOH-PAHs were statistically significant linked to urinary iodine, and iodine mediated the relationship between urinary OH-PAHs and thyroid volume with the mediated proportions of 15.2.

Current status of pesticide effects on environment, human health and it's eco-friendly management as bioremediation: A comprehensive review

Pesticides are either natural or chemically synthesized compounds that are used to control a variety of pests. These chemical compounds are used in a variety of sectors like food, forestry, agriculture and aquaculture. Pesticides shows their toxicity into the living systems. The World Health Organization (WHO) categorizes them based on their detrimental effects, emphasizing the relevance of public health. The usage can be minimized to a least level by using them sparingly with a complete grasp of their categorization, which is beneficial to both human health and the environment. In this review, we have discussed pesticides with respect to their global scenarios, such as worldwide distribution and environmental impacts. Major literature focused on potential uses of pesticides, classification according to their properties and toxicity and their adverse effect on natural system (soil and aquatic), water, plants (growth, metabolism, genotypic and phenotypic changes and impact on plants defense system), human health (genetic alteration, cancer, allergies, and asthma), and preserve food products. We have also described eco-friendly management strategies for pesticides as a green solution, including bacterial degradation, myco-remediation, phytoremediation, and microalgae-based bioremediation. The microbes, using catabolic enzymes for degradation of pesticides and clean-up from the environment. This review shows the importance of finding potent microbes, novel genes, and biotechnological applications for pesticide waste management to create a sustainable environment.

Toxicity and tissue accumulation characteristics of the herbicide pendimethalin under silicon application in ginger (Zingiber officinale Roscoe)

Environmental health and food safety issues potentially caused by the dinitroaniline herbicide pendimethalin (PM) are a worldwide concern. The toxicity response of ginger and tissue accumulation effects of PM on ginger biomass were studied by utilizing PM (CK (clean water), PM1 (0.4%), PM2 (0.67%), PM3 (1.0%), and PM4 (1.67%)) in a dose-response study. It significantly reduced the biomass of ginger under PM4, which is attributed to root damage. The net photosynthetic rate of ginger under PM4 was 11.37% lower than that of CK, which is mainly caused by stomatal limitation. In addition, the ultrastructure of chloroplasts has changed. PM4 caused the accumulation of reactive oxygen species (ROS) in ginger. The activity of superoxide dismutase (SOD) and peroxidase (POD) increased accordingly, maintaining the dynamic balance of ROS content. PM had no significant effect on the expression of ginger α-tubulin genes. PM was significantly accumulated in ginger roots, but not rhizomes. Si increased the productivity of ginger under PM4, which is mainly related to the increase of root development (root application of silicon) and photosynthetic efficiency (foliar application of silicon). Si reduced the ROS content due to the increase in SOD, POD, and catalase (CAT) activity and photosynthetic efficiency.

Endocrine disruptors on and in fruits and vegetables: Estimation of the potential exposure of the French population

Fruits and vegetables are considered to be healthy compared to fats, carbohydrates, and meats. However, their production involves plant protection products (PPPs) or they can contain phytoestrogens which may exhibit endocrine effects. Thus, the exposure to the main PPPs and to phytoestrogens known as endocrine disruptors (EDs) is estimated. PPPs include fungicides, growth substances, herbicides, and insecticides authorised in France. ED-PPPs exposure is estimated from the maximum residue limits (MRLs) of 70 potential ED-PPPs used in France on 64 fruits and vegetables. The estimated exposure to potential ED-PPPs is 509 µg/d and involves agonist and antagonist substances in complex mixtures. Anti-androgens are preeminent, at 353 µg/d. Exposure to genistein and daidzein is calculated from 140 measurements in 9 categories of food-items containing soy. The global exposure to isoflavones in France is evaluated at 6700 µg/d. Phytoestrogen exposure is much higher than that of ED-PPPs. Their endocrine effects should be considered.

Different activation methods in sulfate radical-based oxidation for organic pollutants degradation: Catalytic mechanism and toxicity assessment of degradation intermediates

With the continuous development of industrialization, a growing number of refractory organic pollutants are released into the environment. These contaminants could cause serious risks to the human health and wildlife, therefore their degradation and mineralization is very critical and urgent. Recently sulfate radical-based advanced oxidation technology has been widely applied to organic pollutants treatment due to its high efficiency and eco-friendly nature. This review comprehensively summarizes different methods for persulfate (PS) and peroxymonosulfate (PMS) activation including ultraviolet light, ultrasonic, electrochemical, heat, radiation and alkali. The reactive oxygen species identification and mechanisms of PS/PMS activation by different approaches are discussed. In addition, this paper summarized the toxicity of degradation intermediates through bioassays and Ecological Structure Activity Relationships (ECOSAR) program prediction and the formation of toxic bromated disinfection byproducts (Br-DBPs) and carcinogenic bromate (BrO₃^-) in the presence of Br^-. The detoxification and mineralization of target pollutants induced by different reactive oxygen species are also analyzed. Finally, perspectives of potential future research and applications on sulfate radical-based advanced oxidation technology in the treatment of organic pollutants are proposed.

Pesticides: formulants, distribution pathways and effects on human health - a review

Pesticides are commonly used in agriculture to enhance crop production and control pests. Therefore, pesticide residues can persist in the environment and agricultural crops. Although modern formulations are relatively safe to non-target species, numerous theoretical and experimental data demonstrate that pesticide residues can produce long-term negative effects on the health of humans and animals and stability of ecosystems. Of particular interest are molecular mechanisms that mediate the start of a cascade of adverse effects. This is a review of the latest literature data on the effects and consequences of contamination of agricultural crops by pesticide residues. In addition, we address the issue of implicit risks associated with pesticide formulations. The effects of pesticides are considered in the context of the Adverse Outcome Pathway concept.

Multi-biomarker responses to pesticides in an agricultural population from Central Brazil

We evaluated farmworkers exposed to pesticides and individuals with no history of occupational exposure to pesticides. It was performed the comet assay to evaluate DNA damage. The immunophenotyping of TCD4⁺ lymphocyte subpopulations in peripheral blood was performed by flow cytometry. The single nucleotide polymorphisms (SNPs) in PON1, XRCC1, IL6, IL6R, TNF-α, and MIR137 genes were evaluated by real-time PCR. The exposed group was composed mostly by males (69.44%), with direct exposure to pesticides (56%) and with an average age range of 46 ± 13.89 years, being that 58.3% of farmworkers directly exposed to pesticides and reported the full use of personal protective equipment (PPE). DNA damage was greater in the exposed group (p < 0.05), reinforced by the use of PPE to denote a lower degree of DNA damage (p = 0.002). In this context, in the exposed group, we demonstrated that the use of PPE, age, gender and intoxication events were the variables that most contributed to increase DNA damage (p < 0.0001). Besides, the exposed group showed a significant increase in the subpopulations of T lymphocytes CD3⁺CD4⁺ (p < 0.05) and CD3⁺CD4⁺CD25⁺ (p < 0.0001) and a significant decrease in CD3⁺CD4⁺CD25^-FOXP3⁺ (p < 0.05). SNPs in the TNF-α (rs361525) gene presented a difference in the genotype distribution between the groups (p = 0.002). The genotype distribution of TNF-α (rs361525) was also positively correlated with the DNA damage of the exposed group (r = 0.19; p = 0.01), demonstrating a higher risk of DNA damage in the farmworkers presenting the A mutated allele. Our findings demonstrate that pesticides can exert various deleterious effects on human health by damaging the DNA as well as by influencing the immune system in the case of both direct or indirect exposure and these issues are associated to age, gender, intoxication and the nonuse of PPE.

Agrochemicals and obesity

Obesity has become a very large concern worldwide, reaching pandemic proportions over the past several decades. Lifestyle factors, such as excess caloric intake and decreased physical activity, together with genetic predispositions, are well-known factors related to obesity. There is accumulating evidence suggesting that exposure to some environmental chemicals during critical windows of development may contribute to the rapid increase in the incidence of obesity. Agrochemicals are a class of chemicals extensively used in agriculture, which have been widely detected in human. There is now considerable evidence linking human exposure to agrochemicals with obesity. This review summarizes human epidemiological evidence and experimental animal studies supporting the association between agrochemical exposure and obesity and outlines possible mechanistic underpinnings for this link.

Rno-miR-224-5p contributes to 2,2',4,4'-tetrabromodiphenyl ether-induced low triiodothyronine in rats by targeting deiodinases

Hypothyroidism is commonly associated with substantial adverse impacts on human health, and polybrominated diphenyl ether (PBDE), a kind of classic thyroid hormone disruptor, was speculated to be a potential environmental factor, but its effect on thyroxine metabolism has received little attention. In the present study, we investigated the role and mechanism of rno-miR-224-5p in deiodinase-mediated thyroxine metabolism in rats treated with 2,2',4,4'-tetrabromodiphenyl ether (BDE47), a predominant PBDE congener in humans. BDE47 decreased plasma triiodothyronine (T3) and thyroxine (T4) and increased reverse T3 (rT3) in the rats, and the expression of type 1 deiodinase (DIO1) and type 3 deiodinase (DIO3) increased in both the rats and H4-II-E cells. Rno-miR-224-5p was predicted to target dio1 instead of dio3, according to the TargetScan, miRmap.org and microRNA.org databases. Experiments showed that the rno-miR-224-5p level was decreased by BDE47 in a dose-dependent manner and confirmed that rno-miR-224-5p downregulated both DIO1 and DIO3 in the H4-II-E cells and in the rats, as determined using mimics and an inhibitor of rno-miR-224-5p. Furthermore, DIO1 was observed to be a direct functional target of rno-miR-224-5p, whereas DIO3 was indirectly regulated by rno-miR-224-5p via the phosphorylation of the MAPK/ERK (but not p38 or JNK) pathway. Reportedly, DIO1 and DIO3 act principally as inner-ring deiodinases and are responsible for the conversion of T4 to rT3, but not to T3, and the final clearance of thyroxine (mainly in the form of T2). Our results demonstrated that BDE47 induced low levels of T3 conversion through DIO1 and DIO3, which were regulated by rno-miR-224-5p. The findings suggest a novel additional mechanism of PBDE-induced thyroxine metabolism disorder that differs from that of PBDEs as environmental thyroid disruptors.

Structure-based Identification of Endocrine Disrupting Pesticides Targeting Breast Cancer Proteins

Endocrine disrupting pesticides (EDPs) are exogenous compounds that disrupt endocrine activity. Human exposure to EDPs can occur through occupational contact, and through the consumption of food, milk and water with trace amounts of these pollutants. Several EDPs are epidemiologically linked to breast cancer or are considered as possible carcinogens. However, current evidence is not fully conclusive and their mechanisms of action remain unknown. Thus, the potential interactions between 262 EDPs and 189 proteins associated with breast cancer were evaluated by using a virtual high-throughput screening approach, with AutoDock Vina 1.1.1. The molecular coordinates were previously downloaded from Protein Data Bank and EDCs DataBank, and used for preparation and optimization in Sybyl X-2.0. The best affinity score (-11.0 kcal/mol) was obtained for flucythrinate with the nuclear receptor for vitamin D (VDR). This synthetic pyrethroid, along with other EDPs, such as fluvalinate, bifenthrin, cyhalothrin and cypermethrin, are proposed as multi-target ligands of several proteins related to breast cancer. In addition, the validation of our protocol showed a good accuracy in terms of binding pose prediction and affinity estimation. This study provides a guide to prioritize EDPs for which further in vitro and in vivo analysis could be done to evaluate the risk and possible mechanisms of action of these contaminants and their potential association with breast cancer.