Exposure duration and absorbed dose assessment in pesticide-exposed agricultural workers: Implications for risk assessment and modeling.

INTRODUCTION: Absorbed dose assessment from dermal exposure involves multiplying skin contamination by the dermal absorption coefficient, which is usually defined for the standard workday of 8 h. This strategy may suffer from limitations when the duration of exposure is extremely variable, such as in agricultural exposure to pesticides. OBJECTIVES: The aim of this study was to estimate the dose of mancozeb absorbed by agricultural pesticide applicators in a typical working day considering the real duration of exposure, to compare these estimates with those coming from the use of the Fixed Fractional Approach, and to assess the suitability of the dose estimates in the interpretation of biological monitoring results. METHODS: In a series of real-life field studies on 29 workers applying mancozeb in vineyards for 38 work days, three sets of data were collected: information regarding work activities for each work day, potential (on clothes) and actual skin exposure using the "patch" methodology, and excretion of ethylenethiourea (ETU) in the 24-h pre-exposure and 24-h post-exposure urine samples. The statistical analyses were done using the R Language and Environment for Statistical Computing. RESULTS: Accounting for the duration of exposure led to a substantial reduction in the absorbed dose estimates, compared to the estimates coming from the Fixed Fractional Approach. In particular, absorbed dose by the body, hands' and total absorbed dose were reduced by 50%, 81%, and 80% respectively. The body dose estimated considering both approaches still correlated better with post-exposure 24-h urine ETU levels than the hands' dose, although more than 90% of the estimated total absorbed dose comes from the hands. CONCLUSIONS: An accurate estimate of the absorbed dose, carried out considering the real duration of exposure, can result in a higher correlation with a biomarker of occupational exposure, such as urine ETU, or at least yield more accurate results. This can facilitate the interpretation of biological monitoring data in pesticide-exposed agricultural workers despite the absence of biological exposure limits. ETU should be evaluated as a potentially relevant source of exposure due to ethylenebisdithiocarbamates' (EBDCs) degradation in the formulated product or spray mixture.

Environmental and biological monitoring for the identification of main exposure determinants in vineyard mancozeb applicators.

Grapevine is a vulnerable crop to several fungal diseases often requiring the use of ethylenebisdithiocarbamate (EBDC) fungicides, such as mancozeb. This fungicide has been reported to have goitrogenic, endocrine disrupting, and possibly immunotoxic effects. The aim of this study was to assess workers' exposure in two scenarios of mancozeb application and analyse the main determinants of exposure in order to better understand their mechanism of influence. Environmental monitoring was performed using a modified Organisation for Economic Co-operation and Development (OECD) "patch" methodology and by hand-wash collection, while mancozeb's metabolite, ethylenethiourea (ETU), was measured in 24-h preexposure and postexposure urine samples. Liquid chromatography-mass spectrometry was used for determination of mancozeb and ETU in different kinds of samples. Closed tractor use resulted in 40 times lower potential exposure compared with open tractor. Coveralls reduced skin exposure 4 and 10 times in case of open and closed tractors, respectively. Gloves used during application resulted in 10 times lower hand exposure in open but increased exposure in closed tractors. This study has demonstrated that exposure to mancozeb is low if safe occupational hygiene procedures are adopted. ETU is confirmed as suitable biological marker of occupational exposure to mancozeb, but the absence of biological exposure limits significantly reduces the possibility to interpret biological monitoring results in occupationally exposed workers.

[National plan for prevention in agriculture state of art and prosecution]. / Il piano nazionale di prevenzione in agricoltura. Consuntivo del primo triennio e prospettive.

Agricultural work submits to high risks for safety and health. In 2009, in execution of "workplace health protection pact" (DPCM 17.12.2007), has been defined the National Plan for prevention in agriculture and forestry, whose first three-year program ended in 2012. Goals were: to Systematize and to standardize direction and control activity, defining the number of factories to control, in most italian regions, for high and ubiquitous risks applying homogeneous standards, spending special attention to risks of fatal and serious injury; to develop agricultural machinery trade control, for new and second-hand machinery, for normalizing the whole fleet; to contribute to monitoring of risk factors and injury dynamics, for a better definition of prevention policies; to increase the knowledge of public health agency officers; to identify and to promote technical solutions, helping to define, in proper way, good practices for complex problems; to promote coordination between economic develop policies and prevention policies for agriculture, breeding and forestry, paying attention also to financial helps. The plan, divided in regional plans, obtained most of defined goals and allowed to build a permanent interregional net of referents and expert officers. Next years perspective is to enhance in developing the faced themes and objectives.

Farmers' exposure to herbicides in North Italy: assessment under real-life conditions in small-size rice and corn farms.

Although rice and corn are two main cash crops in Lombardy (North Italy) and their cultivation involves several thousands of farmers, risk assessment of pesticide exposure is rarely done, especially in small and medium sized enterprises. With the use of pads for environmental monitoring (OECD protocol), of pre- and post-exposure 24h urine collection for biological monitoring and of hand wash for hands' exposure, we measured the exposure of 28 agricultural workers to propanil and terbuthylazine in real-life working conditions. In propanil applicators, median daily exposure on the clothes was 73.5µmol per worker, while the exposure on the skin was 22.4µmol. For terbuthylazine, these exposures were 37.2µmol and 0.86µmol per worker, respectively. Median excretion of the propanil metabolite (3,4-dichloroaniline) after exposure was 84nmol in 24h urine, and 13nmol for the metabolite of terbuthylazine. Risk assessment performed by comparing to the AOELs of the applied active ingredients with an estimated internal dose, obtained based on the measured levels of skin and hand exposure and the percentage of dermal absorption of the active ingredients considered showed that 4 propanil workers, and no terbuthylazine workers, were overexposed. Our study helps define and confirm relationships between different exposure determinants, which can be used in the development of tools for risk assessment of exposure to pesticides in small and medium sized enterprises.

Integration of biological monitoring, environmental monitoring and computational modelling into the interpretation of pesticide exposure data: introduction to a proposed approach.

Open field, variability of climatic and working conditions, and the use of complex mixtures of pesticides makes biological and environmental monitoring in agriculture, and therefore risk assessment and management, very complicated. A need of pointing out alternative risk assessment approaches, not necessarily based on measures, but simple, user-friendly and reliable, feasible also in the less advanced situations and in particular in small size enterprises, arises. This aim can be reached through a combination of environmental monitoring, biological monitoring and computational modelling. We have used this combination of methods for the creation of "exposure and risk profiles" to be applied in specific exposure scenarios, and we have tested this approach on a sample of Italian rice and maize herbicide applicators. We have given specific "toxicity scores" to the different products used and we have identified, for each of the major working phases, that is mixing and loading, spraying, maintenance and cleaning of equipment, the main variables affecting exposure and inserted them into a simple algorithm, able to produce "exposure indices". Based on the combination of toxicity indices and exposure indices it is possible to obtain semiquantitative estimates of the risk levels experienced by the workers in the exposure scenarios considered. Results of operator exposure data collected under real-life conditions can be used to validate and refine the algorithms; moreover, the AOEL derived from pre-marketing studies can be combined to estimate tentative biological exposure limits for pesticides, useful to perform individual risk assessment based on technical surveys and on simple biological monitoring. A proof of principle example of this approach is the subject of this article.

[The active search for occupational cancer cases: bladder cancer in Lombardy Region]. / La ricerca attiva dei tumori di origine professionale: il caso del tumore della vescica nella Regione Lombardia.

OBJECTIVE: A study called OCCAM (OCcupational CAncer Monitoring) has been carried out in order to establish a nationwide surveillance system for occupational cancer. This project consists of population-based case control studies where information on past occupations are automatically gathered National Institute for Social Security's archive, cancer cases are obtained from Cancer Registries (CR) and controls are sampled from population files of the National Health Service. As previous results obtained using CR were encouraging, we tried to use regional hospital discharge records as a source of incident cases. DESIGN: We have conducted a population based case-control study with 1568 male bladder cancer cases occurred in the years 1999 and 2000 and 18818 controls randomly sampled from resident population in Lombardy region (Italy). RESULTS: Despite the limits of this approach the following industries were found at increased risk of bladder cancer: leather and shoes industry (OR=1.83; CI 90%: 1.01-3.33; observed: 10); transports (OR=1.28; CI 90%: 0.94-1.76; observed: 37), rubber industry (OR=1.22 CI 90% 0.80-1.85; observed: 19) and printing industry (OR=1.5 CI 90%: 1.10-2.05; observed: 38). CONCLUSION: The ability of OCCAM surveillance system to find known associations using routinely available data offers new opportunities to detect cancer cases likely to be of occupational origin.