Working in an asbestos plant has long been linked to an increased risk for mesothelioma, but new research finds that living near one of these plants may also increase a person’s risk of developing the disease. Leftover waste from asbestos facilities may contribute to as many as ten additional cases of mesothelioma each year in neighboring communities, according to a recent study in the Journal of Exposure Science and Environmental Epidemiology.
Given the relative rarity of mesothelioma, the increased risk to people living near an asbestos plant is significant. “This is a substantial increase over the expected incidence, we assume roughly two to three times higher than expected,” says lead study author Alex Burdorf, a professor of Public Health at Erasmus University in the Netherlands.
Research has already established a link between on-the-job asbestos exposure and mesothelioma. People who have worked in shipyards and other facilities that process asbestos face a significantly higher risk for the cancer than those in the general population. However the risk to people living near asbestos facilities has been unclear.
“It is a long debate as to whether this environmental pollution may result in additional mesotheliomas,” Professor Burdorf says. “This requires a good method of exposure assessment.” A few previous studies have investigated environmental asbestos exposure by gauging residents’ distance to the plant.
Professor Burdorf and his colleagues decided to try a slightly different approach to get a better idea of mesothelioma risk among people living close to an asbestos-processing plant. They looked at both the number and size of polluted sites, and the number of households that were in close proximity to contaminated areas.
The researchers focused on residential areas close to an asbestos-based cement plant in the village of Goor. Between the 1930s and 1970s, this plant distributed asbestos waste to local residents to harden the ground in their yards and driveways, a practice that left the soil in the area polluted.
The researchers ranked nearby postal areas by their level of asbestos exposure: low (0-1 polluted site), intermediate (2-5 polluted sites), and high (6 or more pollute sites). They also analyzed air samples to determine the concentration of asbestos fibers in the air.
In total, the study identified and included 416 sites with asbestos pollution. Nearly 300 of these sites had asbestos waste material at ground level, where it could increase mesothelioma risk. The postal code areas with the highest level of exposure contained, on average, 33 asbestos-contaminated sites. The researchers also noted significantly higher concentrations of asbestos fibers in the air within 5 meters (16 feet) of asbestos-polluted roads.
The researchers determined that people living in residential areas near polluted sites were being exposed to asbestos concentrations at levels high enough to lead to between two and ten additional mesothelioma cases each year.
In an effort to reduce asbestos exposure, in 2003 the local government launched the Clean Up Asbestos Act – an initiative to remove remaining asbestos from the soil in contaminated areas. Professor Burdorf says that cleaning up asbestos pollution should eventually reduce the number of mesothelioma cases in the area studied. However, because mesothelioma can take decades to emerge after asbestos exposure, the results of this clean-up effort may not be seen for decades.
Driece HAL, Siesling S, Swuste PHJJ, Burdorf A. Assessment of cancer risks due to environmental exposure to asbestos. Journal of Exposure Science and Environmental Epidemiology. Published online October 28, 2009.