Assessment of environmental and domestic exposure to tremolite in New Caledonia.

In this study, the authors characterized exposure to asbestos in the population of New Caledonia, an area where a high mesothelioma incidence was found to be associated with the use of a tremolite-containing whitewash on dwellings. The authors collected airborne samples from various sources. Lung tissue samples or bronchoalveolar lavage fluids were available for 80 subjects, who were interviewed regarding their residential and occupational histories. The authors analyzed all samples by analytical transmission electron microscopy. Results indicated that the use of the tremolite-based whitewash may generate high airborne fiber levels and result in asbestos lung contents comparable with those observed in occupational settings. The highest airborne tremolite concentrations were reached during sweeping in whitewashed houses. Lung concentrations of tremolite fibers were significantly higher in subjects exposed to the whitewash than in unexposed subjects, and the concentrations increased with the duration of exposure.

Dietary factors and the risk of lung cancer in New Caledonia (South Pacific).

Our objective was to study the relations between the risk of lung cancer and dietary factors in New Caledonia, in the South Pacific. A population-based case-control study of respiratory cancers was conducted between 1993 and 1995 in New Caledonia; we analyzed data for 134 incident lung cancer cases (109 men and 25 women) and 295 controls (227 men and 68 women) who had completed a food frequency questionnaire. Odds ratios (ORs) associated with food and nutrient intakes were calculated with unconditional logistic regression, with adjustment for smoking, age, and ethnicity. Analyses were performed separately for men and women. Among men, no significant associations were observed with any foods, including vegetables and fruits. Nonetheless, high consumption of dark green leafy vegetables (highest vs. lowest tertile of intake) was associated with decreased risk (OR = 0.5, 95% confidence interval = 0.2-1.2, P for trend = 0.12), particularly among Melanesians (OR = 0.4, 95% confidence interval = 0.1-1.0, P for trend = 0.07). A similar protective effect was also suggested for high consumption of poultry (P for trend = 0.06) and fresh fish (P for trend = 0.08). No significant association was found with nutrients. Among women, the analyses concerned few subjects and were not informative. This study suggests that high consumption of dark green leafy vegetables may reduce the risk of lung cancer among men in this population.

Sinonasal cancer and occupational exposures: a pooled analysis of 12 case-control studies.

OBJECTIVE: In order to examine the associations between sinonasal cancer and occupational exposures other than wood dust and leather dust, the data from 12 case-control studies conducted in seven countries were pooled and reanalyzed. METHODS: The pooled data set included 195 adenocarcinoma cases (169 men and 26 women), 432 squamous cell carcinomas (330 men and 102 women), and 3136 controls (2349 men and 787 women). Occupational exposures to formaldehyde, silica dust, textile dust, coal dust, flour dust, asbestos, and man-made vitreous fibers were assessed with a job-exposure matrix. Odds ratios (ORs) were adjusted for age, study, wood dust, and leather dust, or other occupational exposures when relevant. 95% confidence intervals (CIs) were estimated by unconditional logistic regression. RESULTS: A significantly increased risk of adenocarcinoma was associated with exposure to formaldehyde. The ORs for the highest level of exposure were 3.0 (Cl = 1.5-5.7) among men and 6.2 (CI=2.0-19.7) among women. An elevated risk of squamous cell carcinoma was observed among men (OR=2.5, CI=0.6-10.1) and women (OR = 3.5, CI = 1.2-10.5) with a high probability of exposure to formaldehyde. Exposure to textile dust was associated with non-significantly elevated risk of adenocarcinoma, among women only: the OR for the high level of cumulative exposure was 2.5 (CI = 0.7-9.0). High level of asbestos exposure was associated with a significantly increased risk of squamous cell carcinoma among men (OR = 1.6, CI = 1.1-2.3). CONCLUSIONS: The results of this pooled analysis support the hypothesis that occupational exposure to formaldehyde increases the risk of sinonasal cancer, particularly of adenocarcinoma. They also indicate an elevated risk of adenocarcinoma among women exposed to textile dust, and suggest that exposure to asbestos may increase the risk of squamous cell carcinoma.