Assessment of exposure to pesticides during mixing/loading and spraying of tomatoes in the open field.

Some evidence of exposure-response of metolachlor and pendimethalin for lung cancer and an association of metribuzin with risk of glioma have been reported. The primary objectives in this study were to evaluate exposure and occupational risk during mixing/loading of pesticides and during their application to tomatoes cultivated in open fields. Sixteen farmers were sampled. Respiratory exposure was estimated by personal air sampling using fiberglass filters in a IOM device. Dermal exposure was assessed using skin pads and hand washing. Absorbed doses were estimated assuming 100% lung retention, and 50% or 10% skin absorption for metribuzin, and pendimethalin and metolachlor, respectively. The three pesticides were quantified by gas chromatography tandem mass spectrometry in all matrices. Metolachlor was used as a tracer of contamination of clothes and tractors unrelated to the exposure monitored. Respiratory exposure to metribuzin, used in granular form, was on average more than one order of magnitude higher than exposure to pendimethalin, used in the form of microencapsulated liquid. The actual doses were 0.067-8.08 µg/kg bw, 0.420-12.6 µg/kg bw, and 0.003-0.877 µg/kg bw for pendimethalin, metribuzin, and metolachlor, respectively. Dermal exposure was about 88% of the actual dose for metribuzin and more than 95%, for pendimethalin and metolachlor. For risk assessment, the total absorbed doses (sum of respiratory and skin absorbed doses) were compared with the AOEL for each compound. The actual and absorbed doses of the three pesticides were always lower than the acceptable operator exposure level (AOEL), which are reported to be 234 µg/kg bw, 20 µg/kg bw, and 150 µg/kg bw for pendimethalin, metribuzin, and metolachlor, respectively. In any case, personal protective equipment and spraying devices should be chosen with care to minimize exposure.

[Pollutants from a plant which burns toxic waste in the Province of Arezzo (Tuscany Region, Central Italy): human biomonitoring pilot study to evaluate the possible type of environmental exposure]. / Inquinanti emessi da un impianto di incenerimento di rifiuti speciali nell'area di Arezzo: studio preliminare di monitoraggio biologico umano per identificare la possibile tipologia di esposizione residenziale.

OBJECTIVES: to identify the biomarkers to use in order to evaluate the level and trend of exposure to environmental pollutants from a plant which retrieves and refines precious metals and burns toxic waste. DESIGN: human biomonitoring cross sectional study on a small sample of population resident in the study area. SETTING AND PARTICIPANTS: blood and urinary samples, and questionnaires from volunteers resident at least for 10 years in Civitella in Val di Chiana area (Arezzo Province, Tuscany Region, Central Italy), where the plant is located, and in a control area; they had to be 5-year non-smokers or ex-smokers, in good health status and non occupationally exposed to heavy metals and/or combustion products. MAIN OUTCOME MEASURES: geometric mean and 95th percentile (P95) of mercury (Hg) and cadmium (Cd) blood concentrations, and of the urinary concentrations of antimony (Sb), silver (Ag), arsenic (As), Cd, cobalt (Co), chromium (Cr), Hg, nickel (Ni), platinum (Pt), 1-hydroxypyrene, and trans, trans-muconic acid in the two populations; quantity and pattern of porphyrins in the 24-hour urines of Civitella volunteers. Student's "t" test calculated on the means of data with logarithmic transformation was used to compare the two groups. In case of significant differences linear regression analyses have been performed using questionnaire information. The distribution of observed data was compared with specific reference values. RESULTS: Sb, Cd, and Ni concentrations were significantly higher in Civitella population (39 subjects), while Cr concentration was higher in the control group (18 subjects). No correlations with the individual characteristics have been observed. The 30.3%of subjects who gave their 24- hour urine had a distorted pattern of porphyrins. CONCLUSION: the results confirmed the need to perform human biomonitoring in the Civitella area, increasing the number of samples, using urine as biological matrix, and monitoring at least Sb, Cd, Ni, Pt, Ag, and porphyrins.

Exposure of mobile chipper operators to diesel exhaust.

The current boom of forest biomass is making mobile chippers increasingly popular among forest operators. This motivates concern about the potential exposure of chipper operators to noxious chemicals derived from diesel fuel combustion. The objective of this study was to determine operator exposure to BTEX (benzene, toluene, ethylbenzene, and xylenes) and polycyclic aromatic hydrocarbons (PAHs) generated from diesel combustion. This study sampled 28 mobile chipping operations in the Italian mountains, in order to determine professional exposure to BTEX and PAHs among chipper operators. IOM, Radiello®, and XAD2 samplers were used for the purpose. Operations were divided into industrial and small scale, the former based on powerful chippers with enclosed cabs and the latter on smaller machines without enclosed cabs. We could not detect any measurable exposure to BTEX, while exposure levels for PAHs were very low, especially for what concerned recognized cancer agents. That is likely related to work environment and organization because mobile chippers work in the open-air forest environment and in the presence of very few other machines. PAH concentration was significantly higher inside cabs than outside. None of the operators involved in this research was exposed to BTEX or PAHs above occupational exposure limits.

Determining the exposure of chipper operators to inhalable wood dust.

The study surveyed wood chipping operations in order to determine the exposure of chipper operators to wood dust and suggest suitable countermeasures. The survey included both industrial and small-scale chipping operations, all located in Central Italy, on the Apennine mountain range. During the survey, 60 samples were collected using standardized methods. For the purpose of the tests, each operator carried a wearable active sampler connected to a suction pump. When operators sat inside an enclosed cab, samples were also collected outside the cab in order to gauge the dust abatement effect of a protected work station. Exposure to dust varied widely with wood conditions and machine productivity, and only occasionally exceeded the 5mg m(-3) legal limit. Operators working inside a cab were three times less exposed than operators working outside, and they were never exposed to concentrations exceeding the legal limit. It is adviceable that people working full-time as chipper operators are positioned inside an enclosed cab, for limiting their exposure to wood dust. Small-scale operators are generally part-timers, which further reduces their long-term exposure.

[The quality of analytical data for a proper comparison with the limit value]. / La qualità del dato analitico per un corretto confronto con i valori limite.

The analytical data is usually expressed as a number, in fact, due to the uncertainty of measurement, the "true value" of the analyte, by definition unknowable, is set within a range estimated with a confidence level (typically a probability of 95% with coverage factor 2). The comparison with a limit value must therefore take into account the confidence interval. The quality of the data in Industrial Hygiene is not limited to this. As established by UNI EN 482, the method of sampling and analysis must have an analytical sensitivity of at least one tenth of the limit value of the analyte.

Evaluation of inhaled and cutaneous doses of imidacloprid during stapling ornamental plants in tunnels or greenhouses.

The aim of this research was to assess dermal and respiratory exposure of workers to imidacloprid during manual operations with ornamental plants previously treated in greenhouses or tunnels. A total of 10 female workers, 5 in greenhouses and 5 in tunnels, were monitored for 3 or 5 consecutive days. Actual skin contamination, excluding hands, was evaluated using nine filter paper pads placed directly on the skin. To evaluate the efficacy of protective clothing in reducing occupational exposure we also placed four pads on top of the outer clothing. Hand contamination was evaluated by washing with 95% ethanol. Respiratory exposure was evaluated by personal air sampling. Respiratory dose was calculated on the basis of a lung ventilation of 15 l/min. Absorbed doses were calculated assuming a skin penetration of 10% and a respiratory retention of 100%. Dislodgeable foliar residues (DFRs) were determined during the days of re-entry in order to determine the dermal transfer factor. From the dependence of dermal exposure of hands from DFRs, a mean transfer factor was estimated to be 36.4 cm(2)/h. Imidacloprid was determined by liquid chromatography with selective mass detection and electrospray interface in all matrices analysed. Respiratory dose was 4.1+/-4.0 (0.1-14.3)% and 3.0+/-2.0 (0.6-6.9)% (mean+/-SD (range)) of the total real dose during work in tunnels and greenhouses, respectively. The estimated absorbed doses, 0.29+/-0.45 microg/kg (0.06-2.25 microg/kg) body weight and 0.32+/-0.18 microg/kg (0.07-0.66 microg/kg) body weight (mean+/-SD (range)) in tunnels and in greenhouses, respectively, were less than the acceptable operator exposure level of 0.15 mg/kg body weight and than the acceptable daily intake of 0.05 mg/kg body weight. The hands and exposed skin of all workers were found to be contaminated, indicating that greater precautions, such as daily changing of gloves and clothing, are necessary to reduce skin exposure.

Twenty-four-hour urinary excretion of ten pesticide metabolites in healthy adults in two different areas of Italy (Florence and Ragusa).

The determination of pesticide metabolites in human biological fluids represents an important biomarker of exposure in the general population and exposed workers. In the frame of a prospective study, we measured the 24-h urinary excretion of 10 pesticide metabolites to evaluate non-occupational exposure to pesticides in the general population in two different areas in Italy. We collected 24-h urine samples from 69 healthy adults residing in Florence (Central Italy, n = 51) and Ragusa (Southern Italy, n = 18). The volunteers (25 males, 44 females; mean age 56 years) did not report any occupational exposure. We measured: six alkylphosphates, aspecific metabolites of organophosphorus pesticides [dimethylphosfate (DMP), dimethylthiophosfate (DMTP), dimethyldithiophosfate (DMDTP), diethylphosfate (DEP), diethylthiophosfate (DEDP), and diethyldithiophosfate (DEDTP)]; 3,5,6-trichloro-2-pyridinol (TCP), the main metabolite of chlorpyrifos; 3-phenoxybenzoic acid (3-PBA), a metabolite of pyrethroid insecticides; ethylenethiourea (ETU) a metabolite of ethylenebisdithiocarbamates; methamidophos (METH), an organophosphorus insecticide. We also measured PABA excretion as compliance marker (mean recovery 95%). Dimethylphosphates were found in detectable concentrations in the majority of samples (89.9%, 82.6% and 60.9% for DMP, DMTP and DMDTP, respectively). Urinary diethylphosphates (DEP, DETP, DEDTP) concentrations were above the detection limit in 80.9%, 61.8% and 27.5% of samples, respectively. TCP, 3-PBA and ETU were detected in 78.3%, 53.6% and 21.7% of samples, respectively. Methamidophos was detected in two samples (2.8%). The median number of metabolites detected in the same urine sample was 6 (range 0-9). Excretion levels were highest for alkylphosphates, particularly for DMTP (median: 142.6 nmol/day). Multivariate analysis showed statistically significant differences between these two groups of adults, with higher mean values of urinary excretion of alkylphosphates, TCP and ETU in Florence in comparison to Ragusa. Overall, a very high percentage of 24-h urine samples positive for several pesticide metabolites emerged, with higher levels of urinary daily excretion in subjects residing in the more urbanised area. Our results suggest that food monitoring programs should be supported by general campaigns aimed to reduce the use of pesticides in agriculture.

Evaluation of respiratory and cutaneous doses of chlorothalonil during re-entry in greenhouses.

Five female workers were monitored for 5 consecutive days during re-entry into a greenhouse containing ornamental plants. Skin contamination (excluding hands) was evaluated with nine pads of filter paper placed on the skin. Hand contamination was assessed by washing with 95% ethanol. Respiratory exposure was evaluated by personal air sampling. The respiratory dose was based on a lung ventilation of 15 l/min. The doses absorbed were estimated assuming 10% skin absorption and 100% lung retention. Dislodgeable foliar residue was determined on days of re-entry to evaluate the decay of chlorothalonil. Chlorothalonil was analysed in the different matrices by GC-MS. Respiratory exposure was less than skin contamination, being 11.4+/-5.1% (mean+/-SD) of total exposure. The estimated total absorbed dose did not exceed the acceptable daily intake of 0.03 mg/kg body mass. The hands and unexposed skin of all workers were always found to be contaminated. Greater precautions are therefore needed to reduce skin exposure (clean gloves and suitable clean clothing every day).

Inductively coupled plasma mass spectrometric determination of molybdenum in urine.

A method was developed for the determination of molybdenum (Mo) in human urine by direct dilution of the sample in doubly distilled water with 1% HNO3 (v/v) and inductively coupled mass spectrometry (ICP-MS). In and Y were used as internal standards. Since (98)Mo provides a higher sensitivity, it was chosen as the reference isotope. The influence of different factors, such as sample dilution, HNO3 concentration and the stability of the analyte were evaluated. The detection limit (LOD) was assessed at 0.2 microg/L Mo, while the lower limit of quantification (LOQ) was 0.6 microg/L. Recoveries ranged between 97.2 and 100.7% from solutions containing from 10 to 50 microg/L Mo. Linear calibration curves were generated from 2.1 and 52.1 microg/L with coefficients of variation (CV ) ranging from 1.62 to 3.56%. In order to establish reference values (RV) for molybdenum, the procedure presented here was used to determine Mo in the urine of a population group living in Tuscany, Italy.