Pesticide aerosol characteristics in the vicinity of an agricultural vehicle cab during application.

Pesticide spraying for crop protection leads to the formation of a mist of droplets, part of which is dispersed into the atmosphere. The characteristics of this aerosol, namely its particle size distribution and concentration, were measured during five campaigns involving cereal crop growing, wine grape culture, and orcharding. The measurement method incorporated a tracer product (fluorescein) with the treatment product; the pesticide aerosol concentration was then deduced from the tracer concentration. This method was validated by comparing the pesticide concentration determined by tracing with the concentration determined by direct measurement of the active substance of the pesticide. Concentration was measured using sampling filters, and particle size distribution was measured using cascade impactors. Instruments were mounted on an agricultural vehicle cab to optimize aerosol characterization, and then the cab's confinement efficiency was determined. Aerosols analyzed were fine, featuring mass median diameters between 4 microm and 15 microm; they are therefore highly dispersive. Their concentration is sufficiently high to justify operator protection by an efficient, filtered-air, pressurized cab, especially in wine grape culture and orcharding, which are the sectors where the highest pesticide transfers have been observed.

Effect of organic solvent exposure on chronic kidney disease progression: the GN-PROGRESS cohort study.

It has been suggested that solvent exposure may have a role in the progression of glomerulonephritis (GN) to ESRD, but this has never been tested with an appropriate cohort study design. A total of 338 non-ESRD patients with a first biopsy for primary GN between 1994 and 2001 were included: 194 IgA nephropathies (IgAN), 75 membranous nephropathies (MN), and 69 FSGS. ESRD, defined as an estimated GFR <15 ml/min per 1.73 m2 or dialysis, was registered during a mean follow-up period of 5 yr. Patients' lifelong solvent exposures before and after diagnosis were recorded by interview and assessed by industrial hygienist experts. Cox models were used to estimate adjusted hazard ratios (HR) of ESRD related to exposures. Overall, 15 and 14% of the patients had been exposed at a low and a high level before diagnosis, respectively. Forty-two with IgAN, 12 with MN, and 22 with FSGS reached ESRD. A graded relationship was observed for MN (age- and gender-adjusted HR [95% confidence interval] for low exposure versus none was 3.1 [0.5 to 18.2] and for high exposure versus none was 8.2 [1.9 to 34.7]) and for IgAN (1.6 [0.7 to 3.9] and 2.2 [1.0 to 4.8]) but not for FSGS. Solvent risk was mediated only partly by baseline proteinuria: Adjusted HR for high exposure versus none was 5.5 (1.3 to 23.9) for MN and 1.8 (0.8 to 3.9) for IgAN. In patients with IgAN, there was a trend in increasing HR with exposure duration before and its persistence after diagnosis. These findings support the hypothesized association of solvent exposure with the progression of GN to ESRD. They should prompt clinicians to give greater attention to patients' occupational exposures and possibly to consider professional reclassification.

Behavior of the GABIE, 3M 3500, PerkinElmer Tenax TA, and RADIELLO 145 diffusive samplers exposed over a long time to a low concentration of VOCs.

Diffusive sampling is particularly suited to determine time-weighted average volatile organic compound (VOC) concentration in occupational hygiene and environmental air monitoring. The purpose of this study was to measure the sampling rate variation of four different samplers in a special use--the exposure to a low concentration of volatile organic compound (10 to 200 ppb) for a long period (1 to 14 days). PerkinElmer tube-type adsorbent was packed with Tenax TA and RADIELLO cartridge packed with Carbograph 4. Badge-type activated carbon diffusive samplers 3M 3500 and GABIE were exposed to the same controlled atmospheres of benzene as meta-xylene (BTX) during the same exposure times. Performance samplers were observed for variability of uptake rates according to concentration levels, exposure duration, back diffusion, and competition phenomena at the adsorption sites. Particular benzene behavior has been noted for the thermally desorbable tube-type diffusive sampler: the measured sampling rates decrease with time following an exponential profile. With badge-type active charcoal diffusive samplers, the uptake rates were found to be highly stable and unaffected by time exposure. Overall, in the region of a few tens of ppb, for long-time exposure and for the lightest compounds, 3M 3500 and GABIE diffusive samplers seem the most appropriate diffusive sampling technique in terms of performance and facility in use.

Cancer mortality among municipal pest-control workers.

OBJECTIVES: This epidemiological study was carried out in order to investigate the hypothesis of a relationship between cancer occurrence and occupational exposure in a population of municipal pest-control workers exposed to a wide range of pesticides and other chemicals. METHODS: The study was designed as a mortality historical cohort study. The cohort comprised all subjects ever employed in a municipal pest-control service between 1979 and 1994. The follow-up period lasted from 1979 to 2000. The mortality rates of pest-control workers were compared with those of a regional population. A job exposure matrix was developed, which took into account four types of chemicals: formaldehyde, ethylene oxide, insecticides and rodenticides. RESULTS: None of the 181 subjects of the cohort, leading to 3,107 person-years, was lost to follow-up. Thirty-nine of them died, and all the causes of deaths were ascertained. The standardized mortality ratios (SMRs) for all causes of deaths and for all cancer causes were significantly greater than unity: 1.61 (1.14-2.20) and 2.24 (1.39-3.43), respectively. Non-significant excesses were observed for most cancer sites, except for lung cancer, which had a low SMR. We obtained significant excesses for cancer in workers with more than 20 years of employment [SMR = 2.42 (1.43-3.82)]. Cancer mortality tended to increase insignificantly with formaldehyde and rodenticides exposures, whereas no clear patterns were observed for ethylene oxide and insecticides. However, significant excesses were observed for the highest exposure levels of formaldehyde, insecticides and rodenticides. CONCLUSIONS: This study showed a statistically significant excess of cancer mortality in a population of municipal pest-control workers exposed to a wide variety of chemicals. These cancer sites might be related to occupational activities, since they tended to be more frequently observed when duration of employment increased.