Occupational predictors of urinary dialkyl phosphate concentrations in Mexican flower growers

Association between exposure to organophosphate pesticides and cytokine levels in a population of flower workers in Mexico"

The ability of organophosphate pesticides to disturb immune function has been demonstrated by in vivo and in vitro studies, but evidence of such effects on humans remains scarce. To assess the association between organophosphate pesticides exposure and cytokine levels in Mexican flower workers, a cross-sectional study was carried out. A questionnaire was provided to 121 male flower workers, and urine and blood samples were collected. Using gas chromatography, urinary concentrations of dialkylphosphate metabolites were determined. The serum cytokine levels, IL-4, IL-5, IL-6, IL-8, and IL-10, were measured using multiplex analysis, and levels of INF-γ and TNF-α by ELISA. We found that a higher dialkylphosphate concentration decreased the pro-inflammatory cytokines INF-γ (β = -0.63; 95% CI: -1.22, -0.05), TNF-α (β= -1.18; 95% CI: -2.38, 0.02), and IL-6 (β= -0.59; 95% CI: -1.29, 0.12), and increased IL-10 (β=0.56; 95% CI: 0.02, 1.09), the main anti-inflammatory cytokine, suggesting an imbalance of the immune response in flower workers.

Determination of pesticide residues in urine by chromatography-mass spectrometry: methods and applications

Introduction

Pollution has emerged as a significant threat to humanity, necessitating a thorough evaluation of its impacts. As a result, various methods for human biomonitoring have been proposed as vital tools for assessing, managing, and mitigating exposure risks. Among these methods, urine stands out as the most commonly analyzed biological sample and the primary matrix for biomonitoring studies.

Objectives

This review concentrates on exploring the literature concerning residual pesticide determination in urine, utilizing liquid and gas chromatography coupled with mass spectrometry, and its practical applications.

Method

The examination focused on methods developed since 2010. Additionally, applications reported between 2015 and 2022 were thoroughly reviewed, utilizing Web of Science as a primary resource.

Synthesis

Recent advancements in chromatography-mass spectrometry technology have significantly enhanced the development of multi-residue methods. These determinations are now capable of simultaneously detecting numerous pesticide residues from various chemical and use classes. Furthermore, these methods encompass analytes from a variety of environmental contaminants, offering a comprehensive approach to biomonitoring. These methodologies have been employed across diverse perspectives, including toxicological studies, assessing pesticide exposure in the general population, occupational exposure among farmers, pest control workers, horticulturists, and florists, as well as investigating consequences during pregnancy and childhood, neurodevelopmental impacts, and reproductive disorders.

Future directions

Such strategies were essential in examining the health risks associated with exposure to complex mixtures, including pesticides and other relevant compounds, thereby painting a broader and more accurate picture of human exposure. Moreover, the implementation of integrated strategies, involving international research initiatives and biomonitoring programs, is crucial to optimize resource utilization, enhancing efficiency in health risk assessment.

Pesticide use patterns and their association with cytokine levels in Mexican flower workers

OBJECTIVE

Occupational exposure to pesticides is a known risk for disrupting cellular immune response in flower workers due to their use of multiple chemical products, poor work conditions, and inadequate protection. Recently, the analysis of pesticide use patterns has emerged as an alternative to studying exposure to mixtures of these products. This study aimed to evaluate the association between exposure to different patterns of pesticide use and the cytokine profile of flower workers in the State of Mexico and Morelos, Mexico.

METHODS

A cross-sectional study was carried out on a population of 108 flower workers. Serum levels of IL-4, IL-5, IL-6, IL-8, IL-10 cytokines were analyzed by means of multiplex analysis, and TNF-α and IFN-γ using an ELISA test. Pesticide use patterns were generated by principal components analysis.

RESULTS

The analysis revealed that certain patterns of pesticide use, combining insecticides and fungicides, were associated with higher levels of pro-inflammatory cytokines, particularly IL-6 and IFN-γ.

CONCLUSION

These findings indicate that pesticides may possess immunotoxic properties, contributing to increased inflammatory response. However, further comprehensive epidemiological studies are needed to establish a causal relationship.

Effects of an organic diet intervention on the levels of organophosphorus metabolites in an adult cohort

Pesticides are a group of organic compounds used to control weeds or insect infestations in agriculture. Diet is the major route of human exposure to these compounds, which can cause serious health problems, even when the intake occurs at low concentrations. Hence, the consumption of organic food is an appropriate strategy to minimize the exposure to pesticides. A prospective, randomized study was conducted to assess the impact of an organic dietary intervention on the levels of urinary dialkyl phosphates (DAP). A screening of 204 pesticides was also carried out in order to confirm the absence of these compounds in organic food. The analytical results showed that only 20 of the 204 pesticides (9.8 %) had concentrations above the limit of quantification in one or more samples of the organic food consumed by the participants. It is substantially lower than the levels of pesticides found in other studies analysing conventional food, confirming the diet as suitable for the organic dietary intervention. A general reduction of most DAP metabolites in urine was found, being significant (p < 0.05) the decrease of dimethyl phosphate (DMP) (0.49 µg/g creatinine in Day 1 vs. 0.062 µg/g creatinine in Day 6), dimethyl thiophosphate (DMTP) (0.49 µg/g creatinine in Day 1 vs. 0.093 µg/g creatinine in Day 6) and diethyl phosphate (DEP) (0.28 µg/g creatinine in Day 1 vs. 0.12 µg/g creatinine in Day 6). In addition, the molar score for the total dimethyl DAP (ΣMP) and total dialkyl phosphate (ΣDAP) also showed significant differences after changing a conventional diet by an organic diet, being reduced from 0.008 µmol/g to 0.002 µmol/g for ΣMP and from 0.012 µmol/g to 0.003 µmol/g for ΣDAP. To the best of our knowledge, this is the first study that evaluates both the impact of an organic diet in the exposure to DAP and the levels of 204 pesticides in the organic food provided to the participants. In summary, the consumption of organic products decreases the dietary intake of pesticides, thus reducing also the potential adverse effects on human health.

Effects of urinary of organophosphate metabolites on nerve conduction and neurobehavioral performance among farmers in northern Thailand

Farmers are regarded as a high-risk population for pesticide exposure because of the frequency of their occupational exposure to organophosphate (OP) pesticides. The purposes of this study were 1) to compare urinary OP metabolites, nerve conduction, and neurobehavioral (NB) performance between farmers and a control group, as well as between baseline measurement and after spraying OP pesticides; 2) to investigate the factors associated with increased urinary OP metabolites after spraying OP pesticides; and 3) to investigate the effects of OP metabolites on changes in nerve conduction and NB performance after spraying OP pesticides. This study was conducted with a sample size of 71 farmers and a control group of 26. The findings showed that after spraying OP pesticides total dialkylphosphate (DAP) levels were significantly higher than baseline levels. Multiple linear regression showed that increased urinary OP metabolites among farmers after spraying pesticides were negatively associated with wearing a mask when spraying OP pesticides and positively associated with the number of years of farm work and type of sprayer equipment. The results also showed a positive association between the increased urinary total diethylphosphate (DEP) levels and the decreased amplitude of motor nerve conduction. Furthermore, a positive correlation was observed between increased urinary total DEP and decreased right amplitude of sympathetic skin response (SSR). An increase in urinary total DMP was positively associated with a decrease in raw score and a standard score of visual-motor integration (VMI). Our findings provide evidence that exposure to OP pesticides can cause a deficit in nerve conduction and NB performance in farmers. These findings may contribute to the early detection of neurological disease and inform strategies to prevent damage to the peripheral and central nervous systems.

Exposure to organophosphate insecticides, inappropriate personal protective equipment use, and cognitive performance among pesticide applicators

Inappropriate use of personal protective equipment (PPE) among pesticide applicators may increase urinary organophosphate (OP) metabolite levels and subsequently increase risks of cognitive performance. Therefore, this study aims to (1) compare urinary OP metabolite levels and cognitive performance between pre-and post-pesticide application seasons; (2) PPE use and factors associated with PPE use linked to increased urinary OP metabolite levels during pesticide application; and (3) the association between urinary OP metabolite levels and cognitive performance. This longitudinal follow-up study on 79 pesticide applicators was carried out between October 2021 and January 2022. The applicators were interviewed, collected urine samples, and tested for cognitive performance in pre-and post-pesticide application seasons. The results found that the levels of urinary OP metabolites in post-application season were significantly higher than those in pre-application season (p < 0.001). Multiple linear regression analysis found that increased total diethylphosphate (DEP) and total dialkylphosphate (DAP) levels were associated with not wearing gloves while mixing pesticides [beta (β) ± standard error (SE) = -43.74 ± 18.52, 95% confidence interval (95% CI) = -80.84, -6.64 for total DEP and -50.84 ± 19.26, 95% CI = -89.41, -12.26 for total DAP] and also with not wearing a mask while spraying pesticides (β ± SE = -31.76 ± 12.24, 95% CI = -56.28, -7.24 for total DEP and -33.20 ± 12.63, 95% CI = -58.49, -7.92 for total DAP) after adjusting for covariates. The scores of Montreal Cognitive Assessment-Thai, Thai Mental State Examination, and Mini-Cognitive test in post-pesticide application were significantly lower than those in pre-pesticide application (p < 0.001). However, no association was found between urinary OP metabolite levels and cognitive decline. Our findings indicate that inappropriate PPE use during pesticide application was the major factor affecting urinary OP metabolite levels among pesticide applicators. Wearing gloves when mixing pesticides and a mask when spraying pesticides were key factors in reducing occupational exposure to OP. Exposure to OP at low levels and for short periods of exposure may not affect cognitive performance significantly. Therefore, long-term exposure and exposure to high levels of OP should be investigated further.

A review on pesticides in flower production: A push to reduce human exposure and environmental contamination

In several countries, flower import regulations are restricted to food security, by establishing maximum residue limits (MRL) for pesticides in flower-based food products and biosafety, in order to limit the circulation of vectors, pests and exotic species across borders. In this context, the lack of limits on pesticides in flower-products for ornamental purposes can influence the pesticide overuse in production areas, as well as the transfer of contaminated products between countries. Therefore, the purpose of this review was to discuss possible adverse effects on human and environmental health of pesticides used in floriculture, evaluating regulations on the use of these pesticides in the main importing and flower-producing countries. This review included 92 documents. The use of 201 compounds was identified by interviews and analytical measurements. Among them, 93 are banned by the European Union (EU), although 46.3 % of these compounds have been identified in samples from European countries. Latin American countries have a large number of scientific publications on pesticides in flower production (n = 51), while the EU and China have less studies (n = 24) and the United States and Japan have no studies. Regarding adverse health effects, poorer neurobehavioral development, reproductive disorders, congenital malformations and genotoxicity have been reported for residents of flower production areas and workers throughout the flower production cycle. Studies including water samples show overuse of pesticides, while environmental impacts are related to water and air contamination, soil degradation and adverse effects on the reproduction and development of non-target organisms. This review points out that the absence of MRL for non-edible flowers can be crucial for the trade of contaminated products across borders, including pesticides banned in importing countries. Furthermore, setting limits on flowers could reduce the use of pesticides in producing countries.

Cumulative exposure characteristics of vegetable farmers exposed to Chlorpyrifos in Central Java - Indonesia; a cross-sectional study

Background

Agriculture is a major economic sector in Indonesia. Chemical pesticides are widely being used in agriculture for controlling pest. There is a growing concern that pesticide exposure, particularly chlorpyrifos (CPF) exposure, combined with other occupational characteristics that determine the level of exposure, can lead to further health impacts for farmers. Our objective was to evaluate the cumulative exposure characteristics among farmers exposed to CPF by using a validated algorithm.

Methods

We conducted a cross-sectional study of 152 vegetable farmers aged 18–65 who actively used CPF for at least 1 year in Central Java, Indonesia. Subject characteristics were obtained using a structured interviewer-administered questionnaire, addressed for sociodemographic and work-related characteristics. The cumulative exposure level (CEL) was estimated as a function of the intensity level of pesticide exposure (IL), lifetime years of pesticide use and the number of days spraying per year. CEL was subsequently classified into two groups, high and low exposure groups. The difference in characteristics of the study population was measured using Chi-square, independent-t or Mann-Whitney test. Association between CEL and its characteristics variables were performed by multiple linear regression.

Results

Seventy-one subjects (46.7%) were classified as the high exposure group. The use of multiple pesticide mixtures was common among our study population, with 94% of them using 2 or more pesticides. 73% reported direct contact with concentrated pesticides product, and over 80% reported being splashed or spilt during preparation or spraying activity. However, we found that the proportion of proper personal protective equipment (PPE) use in our subjects was low. Higher volume of mixture applied (p <  0.001) and broader acres of land (p = 0.001) were associated with higher cumulative exposure level, while using long-sleeved clothes and long pants (p <  0.05) during pesticide spraying were associated with lower cumulative exposure after adjusted for age and gender.

Conclusions

These findings indicate an inadequate knowledge of using pesticides properly. Thus, we recommend comprehensive training on pesticide usage and encourage proper PPE to reduce the exposure level.

Association between Organophosphate Pesticide Exposure and Insulin Resistance in Pesticide Sprayers and Nonfarmworkers

Insulin resistance is a risk factor for various diseases. Chronic organophosphate exposure has been reported to be a cause of insulin resistance in animal models. This cross-sectional study aimed to evaluate the association between organophosphate exposure and insulin resistance in pesticide sprayers and nonfarmworkers. Participants aged 40-60 years, consisting of 150 pesticide sprayers and 150 nonfarmworkers, were interviewed and assessed for their homeostatic model assessment of insulin resistance (HOMA-IR) level. Organophosphate (OP) exposure was measured in 37 sprayers and 46 nonfarmworkers by first morning urinary dialkyl phosphate (DAP) metabolites. The DAP metabolite levels were not different in either group except for diethylthiophosphate (DETP; p = 0.03), which was higher in sprayers. No significant association was observed between DAP metabolite levels and HOMA-IR. Wearing a mask while handling pesticides was associated with lower dimethyl metabolites (95% CI = -11.10, -0.17). Work practices of reading pesticide labels (95% CI = -81.47, -14.99) and washing hands after mixing pesticide (95% CI = -39.97, -3.35) correlated with lower diethyl alkylphosphate level. Overall, we did not observe any association between OP exposure and insulin resistance in pesticide sprayers and the general population. However, personal protective equipment (PPE) utilization and work practice were associated with OP exposure level in sprayers.

Factors affecting use of personal protective equipment and pesticide safety practices: A systematic review

An evidence-based understanding of factors influencing PPE use and pesticide safety practices has the benefit of facilitating the design of interventions to minimize exposure to pesticides and the promotion of the utilization of PPE and safety practices among agricultural pesticide handlers. The aim of this study, therefore, is to review the available literature on the use of PPE in agricultural pesticide handlers in world regions, and also the factors associated with the use of PPE and pesticide safety practices in farmers and farm workers. Full-text articles published on PubMed, Scopus, and ISI databases between 1999 and 2019 were reviewed and the scientific evidence was evaluated. One hundred and twenty-one articles were eligible for inclusion in this quantitative synthesis: 110 evaluated PPE use in agricultural pesticide handlers, and 23 focused on factors affecting PPE use and pesticide safety practices. Considerable evidence was found to show that the most basic PPE worn among pesticide handlers in all world regions was a long sleeve shirt (66.1%), long sleeve trousers (71.1%), and a hat (47.3%). The lowest basic PPE worn was an apron (8.6%), goggles (24.3%), gloves (40.5%), boots (42.3%), and mask (43.2%). The PPE worn (except for an apron) was proportionally higher in farmers than in farm workers. There is considerable evidence to suggest that the significant determinants associated with PPE use and pesticide safety practices are as follows: (1) demographic factors (i.e. education/literacy level, experience of illness, income); (2) farm structure factors (i.e. farm size); (3) behavioral and psychosocial factors (i.e. contact with pesticides, perceptions, attitudes, awareness, norms and beliefs); and (4) environmental factors (i.e. information about pesticides, access to extension services, training program, and farm organization). Therefore, there is a recognizable need for a life-long education program with training to change the perception and behavior of pesticide handlers sustainably.

Considerations for cholinesterase biomonitoring in flower and ornamental plant greenhouse workers

Flower cultivation in greenhouses enhances productivity and ensures high-quality product supply throughout the year. However, under such protected environments, climate conditions are designed to favor flower growth and can intensify occupational exposure to pesticides. In this study, flower greenhouse workers were tested for cholinesterase inhibition, a valuable indicator of occupational exposure to organophosphate and carbamate pesticides. The quantified inhibition was also associated with working practices using these outcomes to explore ways in which provisions of regulatory Occupational Health Control Programs can be met considering the peculiarities of this working environment. Despite their preliminary nature, and considering that workers had not been previously tested, the obtained results suggested that the designed pre- and post-screening process, enabled biomonitoring of the exposed population. The pre-exposure sample was collected after 11 days from pesticide spraying and the post-exposure sample was collected no later than 10 days after pesticide spraying. AChE activity was significantly depressed in flower greenhouse workers, comparing pre- and post-exposure intervals. Nursery workers, often overlooked, presented greater inhibition of AChE activity. Such finding is consistent with effects believed to be associated with the described job and the way activities are conducted, once nursery workers are regularly exposed to low levels of pesticides owing to their continuous contact with sprayed crops. As predicted by Occupational Safety and Health Standards, establishing biomonitoring programs is achievable, despite the intensive use of pesticides. Quantification is important to target the exposed population but is not sufficient to assure good working conditions and avoid exposure. Administrative and working practices, such as job misclassification, non-compliance with national regulations for occupational health control, pesticide handling, lack of REI protocols, and unsuitable delivery of PPE, must be addressed. Anything less will contribute to worsening an already bleak picture in terms of occupational safety and health in flower and ornamental plant greenhouses.