175 research outputs found
Exposure and risk profiles: From field studies to typical exposure and risk scenarios
No full textPesticides are among the most employed synthetic chemicals, and for which there, is the largest database of chemical and toxicological information that allows establishing health-based exposure limits. Protection of pesticide applicators and of the general population from over-exposure is both an ethical necessity and a contribution to planetary health. So far the exposure occupational and population exposure limits could not be efficiently used for health protection, due to the limitations of current techniques to be employed on a wide scale. Biological monitoring of exposure is a viable technique for occupational protection and for the assessment of chemical risk of the population Pesticides are intrinsically toxic, and their manipulated quantity and wide use requires adequate protection to reduce the potential impact on applicators’ health. Before marketing the exposure-related health risk of each active substance is assessed through models, to demonstrate that at least in one application scenario its use does not cause an unacceptable health risk to the exposed workers. This reasonably safe scenario identifies the modalities for an effective and safe use that are coded as “Good Agricultural Practices” (GAP) and summarized in the label's instructions. However, real-life work may be conducted out of the frame of GAP, with a consequent health risk for the exposed workers, which must be assessed and managed. In real-life working conditions, risk assessment is seldom, if at all, performed since the task is linked to economic cost, the limited availability of trained personnel and logistics necessary to reach small, family-based enterprises, which are poorly covered by occupational health services. Additional difficulties are represented by the variability of working patterns, climatic conditions, and the frequent use of mixtures of pesticides. The main tools currently available for the exposure and risk assessment “in the field,” namely, biological and environmental monitoring, show important limits for their use in agriculture. In particular, assessment of dermal contamination involves very complicated and expensive procedures that cannot be carried out on a routine basis. Biological monitoring faces strong limitations, including lack of fully validated biomarkers and biological exposure limits.
The exposure estimate and risk estimate done for a specific worker at a specific time during one of his workdays using any of the aforementioned methods represent only one point on a map of exposures and risk for workers applying pesticides. Instead of a point, we are interested in the whole map of exposure and risk. To make risk assessment available to all workers in various working conditions, there is a need of simple, user-friendly, and reliable approaches to estimate the levels of exposure (and of related occupational risk) experienced by the workers during typical, rather than actual, activities. We refer to these typical conditions as exposure and risk profiles.
This chapter underlines the variables influencing exposure and exposure assessment in real-life work scenarios, reviews the drawback and difficulties of performing exposure assessment using environmental and/or biological monitoring, introduces the concept of exposure scenarios and risk profiles, reviews the current state of risk profile development and their main characteristics, and presents a way forward to integrate the exposure assessment through the exposure score (or index) and the toxicity score to create a risk assessment scheme or a map of exposure and risk in typical exposure scenarios.
when measurements can be compared with suitable limit values. This possibility is currently employed only for few metals and organics of industrial interest, but only insufficiently for pesticides. We propose a paradigm to assess exposure and exposure-related risk of pesticides based on the measurement of their metabolites excreted in urine and on the elaboration of results from field exposure studies. Regression models allow forecasting the pesticide excretion associated to a systemic dose of pesticide corresponding to its acceptable occupational exposure limit (AOEL) for agricultural pesticide applicators. For this indicator and its corresponding limit value, we propose the name of equivalent biological exposure limit (EBEL). To demonstrate the proposed procedure and to highlight its utility and current limitations, we report data and elaborations from a previously published study that allows establishing a provisional value for an herbicide. This procedure can be adapted to fill the identified sources of uncertainty and to derive a limit value tha
Definition and establishment of biological exposure limits of pesticides for the interpretation of biological monitoring data
No full textPesticides are among the most employed synthetic chemicals, and for which there, is the largest database of chemical and toxicological information that allows establishing health-based exposure limits. Protection of pesticide applicators and of the general population from over-exposure is both an ethical necessity and a contribution to planetary health. So far the exposure occupational and population exposure limits could not be efficiently used for health protection, due to the limitations of current techniques to be employed on a wide scale. Biological monitoring of exposure is a viable technique for occupational protection and for the assessment of chemical risk of the population when measurements can be compared with suitable limit values. This possibility is currently employed only for few metals and organics of industrial interest, but only insufficiently for pesticides. We propose a paradigm to assess exposure and exposure-related risk of pesticides based on the measurement of their metabolites excreted in urine and on the elaboration of results from field exposure studies. Regression models allow forecasting the pesticide excretion associated to a systemic dose of pesticide corresponding to its acceptable occupational exposure limit (AOEL) for agricultural pesticide applicators. For this indicator and its corresponding limit value, we propose the name of equivalent biological exposure limit (EBEL). To demonstrate the proposed procedure and to highlight its utility and current limitations, we report data and elaborations from a previously published study that allows establishing a provisional value for an herbicide. This procedure can be adapted to fill the identified sources of uncertainty and to derive a limit value that corresponds to the ADI-ARfD for the general population. The establishment of limit values according to this strategy allows performing risk assessment in the pesticide workers and in the general population by exploiting the capability of modern analytical approaches to the targeted measurement of trace chemicals in biological specimens
Methods for the Identification of Outliers and Their Influence on Exposure Assessment in Agricultural Pesticide Applicators : a Proposed Approach and Validation Using Biological Monitoring
No full textThe "patch" approach for skin exposure assessment can easily be combined with biological monitoring in real-life pesticide studies. Nevertheless, this approach is sensitive to outliers, with values markedly deviating from other members of the sample, which can result in a gross overestimation of exposure. This study aimed at developing methods for outlier identification and validating them while using biological monitoring. Twenty-seven workers applying mancozeb in Italian vineyards participated in this study. Their skin exposure was estimated while using the patch methodology, while ethylene-thiourea (ETU) was measured in the 24-h post-exposure urine as a biomarker of exposure. The outliers were detected using methods that were based on the multiplication of the median, the median absolute deviation, and boxplots. The detection rate varied between 2.3% and 17.3%. The estimated median skin exposure of 3.2 μg was reduced to 1.2 μg when the modified Z score was used. The highest reduction in the skin exposure was above 54 μg. The use of the modified Z score for outlier detection resulted in an increase in the correlation coefficient between the skin exposure and the urine ETU levels from 0.46 to 0.71, which suggested the validity of the approach. Future studies should standardize and improve the methods for pesticide exposure and risk assessment
The role of pesticide exposure in the genesis of Parkinson's disease : epidemiological studies and experimental data
No full textParkinsons' disease (PD) is the most common neurodegenerative movement disorder
that is a consequence of premature death of dopamine-containing neurons in the
substantia nigra. A number of observations have led to the hypothesis that
environmental factors, including pesticides, play a significant role in the
development of PD. Among pesticides, most commonly herbicides (paraquat in
particular) and insecticides have been considered. The aim of this study is to
address the uncertainties provided by epidemiological studies on the role of
pesticide exposures in the development of PD, with the help of experimental
toxicological data. Animal models that reproduce all clinical and pathological
features of human PD are not available. In addition, the fundamental questions
relate to the extrapolation from experimental to actual human exposure, taking
also into account the role of genetic factors. Available measurements or
estimates of human exposure levels that are significantly lower than those used
in animal experimentation provide little support for a causal correlation between
pesticide exposure and development of PD in humans. A possible role of acute
poisonings or episodes of excessive exposure, and/or of combined exposures
especially at early age and/or in the presence of certain genetic variants can be
hypothesised. Follow up of survivors of acute poisonings by pesticides would
provide information useful in this respect. According to the available data, from
a public health point of view, prevention of "high" exposures, even asymptomatic
ones, especially in utero and during early age is a priority
Hospital Employees' Well-Being Six Months after the COVID-19 Outbreak: Results from a Psychological Screening Program in Italy
No full textThe COVID-19 outbreak has taken a heavy toll on the mental well-being of healthcare workers. This study aims to describe a psychological screening program developed at a large University Hospital in Milan, Italy, and assess the psychological outcomes of employees and associated factors. A survey was electronically conducted among hospital employees between July and October 2020. Sociodemographic data, information about COVID-19 experience and three scales assessing anxiety (STAI-Y1), depression (HAM-D) and post-traumatic stress disorder (PCL-5) were collected. A total of 308 employees (80% women; mean age 45.1 years) responded: 16% physicians, 68% other healthcare professionals, and 16% administrative staff. Employees reported moderate/severe symptoms of anxiety (23%), depression (53%), and post-traumatic stress disorder (40%). At multivariate logistic regression analysis, having suffered a loss for COVID-19 in the personal context was independently associated with higher risk of moderate/severe anxiety (OR = 2.40; 95% CI 1.16–4.98), being female was associated with higher risk of moderate/severe depression (OR = 2.82; 95% CI 1.43–5.59), and having had a family member affected by COVID-19 was associated with higher risk of moderate/severe post-traumatic stress disorder (OR = 2.75; 95% CI 1.01–7.48). COVID-19 personal experience may have a profound impact on hospital workers’ mental health and should be considered in supportive interventions
Pesticides
No full textPesticides are substances or mixtures used to control living organisms that damage crops or goods, transmit or cause diseases and other unwanted events, such as the uncontrolled expansion of endogenous living species, or infestation by non‐native ones. Unwanted living organisms include animals, such as insects and rodents, invading plants, such as weeds and ornamental flowers, shrubs and trees, microorganisms and viruses that cause transmittable diseases to plants, animals, and humans
Long-term neurotoxicological effects of anticholinesterases after either acute or chronic exposure
No full textShort occupational exposure to glyphosate and its biomonitoring via urinary levels of glyphosate and metabolite AMPA (Amino-MethylPhosphonic acid), in Italian vineyard workers.
No full textGlyphosate, an herbicide largely used in various contexts, can have adverse effects on human health. Although it is currently the most applied pesticide worldwide, few studies evaluated the extent of human exposure via biomonitoring. To expand such information, biological monitoring of exposure to glyphosate was conducted. The study has a before-and-after design to demonstrate the immediate impact of short-term interventions. Accordingly, the urine concentrations of glyphosate and its main biodegradation product (amino-methylphosphonic acid- AMPA) were measured before and the day after the single herbicide application in 17 male winegrowers. Urine samples were analyzed by high performance liquid chromatography coupled with a triple quadrupole mass spectrometer equipped with an electrospray ionization source. Glyphosate and AMPA were not detectable in pre-application urine samples (limit of quantification for glyphosate (LOQG) was 0.1 μg/L; limit of quantification for AMPA (LOQAMPA) was 0.5 μg/L). After application, glyphosate urinary levels were above LOQG in all workers. The median, min, and max values were 2.30, 0.51, and 47.2 μg/L, respectively. The same values were found for 50 %, 5 % and 95 % percentiles. After assigning numerical values, such as one half the LOQ, to each of the non-detects, the "z" of Wilcoxon matched-pairs signed-ranks test was -3.62 (p = 0.0003), suggesting the pre-application values being significantly lower than the post-application urinary glyphosate concentration. A similar analysis was not feasible with AMPA urinary levels, which were detectable only in 3 workers, after application. 12 (71 %) workers were significantly exposed to glyphosate, but adherence to the adoption of personal protective equipment was good: 14 (82 %) workers used gloves, 13 (76 %) used overalls and 13 (76 %) facial masks. Our data show that glyphosate can be absorbed by the workers after a single application and confirms the usefulness of biomonitoring in exposed workers. Further studies are needed in larger working populations and with multiple glyphosate applications, as well as to evaluate the correlations of glyphosate urine levels with exposure questionnaire data, in order to assess the actual relevance of risk and protection factors
The ethics of human volunteer studies involving experimental exposure to pesticides: unanswered dilemmas
No full textThe controversy about the use of data from human volunteer studies involving experimental exposure to pesticides as part of regulatory risk assessment has been widely discussed, but the complex and interrelated scientific and ethical issues remain largely unresolved. This discussion paper, generated by authors who comprised a workgroup of the ICOH Scientific Committee on Rural Health, reviews the use of human experimental studies in regulatory risk assessment for pesticides with a view to advancing the debate as to when, if ever, such studies might be ethically justifiable. The discussion is based on three elements: (a) a review of discussion papers on the topic of human testing of pesticides and the positions adopted by regulatory agencies in developed countries; (b) an analysis of published and unpublished studies involving human testing with pesticides, both in the peer-reviewed literature and in the JMPR database; and (c) application of an ethical analysis to the problem. The paper identifies areas of agreement which include general principles that may provide a starting point on which to base criteria for judgements as to the ethical acceptability of such studies. However, the paper also highlights ongoing unresolved differences of opinion inherent in ethical analysis of contentious issues, which we propose should form a starting point for further debate and the development of guidelines to achieve better resolution of this matter.<br/
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