Pleural Mesothelioma in New Caledonia: Associations with Environmental Risk Factors

Environmental Health Perspectives. 2010 Dec 29. [Epub ahead of print] [Link].

Baumann F, Maurizot P, Mangeas M, Ambrosi JP, Douwes J, Robineau B.

University of New Caledonia.

Abstract

Background: High incidences of malignant mesothelioma (MM) have been observed in New Caledonia. Previous work showed an association between MM and soil containing serpentinite.

Objectives: To study the spatial and temporal variation of MM and its association with environmental factors.

Methods: All 109 MM cases recorded in the Cancer Registry of New Caledonia between 1984 and 2008 were investigated. Spatial, temporal and space-time cluster analyses were performed. We conducted an ecological analysis involving 100 tribes over a large area including those with the highest incidence rates. Associations with environmental factors were assessed using logistic and Poisson regression analyses.

Results: The highest incidence was observed in the Houaïlou area with a world age standardised rate of 128.7 per 100,000 person-years; 95%CI: 70.41–137.84. A significant spatial cluster grouped 18 tribes (31 observed cases vs 8.12 expected cases, p=0.001), but no significant temporal clusters were identified. The ecological analyses identified serpentinite on roads as the greatest environmental risk factor: odds ratio = 495.0, 95%CI: 46.2–4679.7; multivariate incidence rate ratio = 13.0, 95%CI: 10.2-16.6. The risk increased with serpentinite surface, proximity to serpentinite quarries and distance to the peridotite massif. The association with serpentines was stronger than for amphiboles. Living on a slope and close to dense vegetation appeared protective. The use of whitewash, previously suggested to be a risk factor, was not associated with MM incidence.

Conclusions: Presence of serpentinite on roads is a major environmental risk factor for mesothelioma in New Caledonia.