Occupational airborne particulates: Assessing the environmental burden of disease at national and local levels
Environmental burden of disease series No. 7
This guide provides practical information for assessing the burden of nonmalignant respiratory diseases that arise from occupational exposures to airborne particulates (mainly dusts). The respiratory diseases are asthma, chronic obstructive pulmonary disease (COPD), and the three main pneumoconioses: asbestosis, silicosis and coal workers’ pneumoconiosis. The focus is on assessing the current burden of disease that results from past and current occupational exposures to airborne particulates. Exposure is estimated from country workforce data, including exposure data for different occupations or industries based on European data. In the approach proposed for asthma and COPD, the relative risks for exposed populations versus nonexposed populations are obtained from the literature. These data are then combined with the exposure data to calculate a population Attributable Fraction (AF) for each country (i.e. the fraction of deaths or disability from asthma or COPD in a country that is attributable to occupational exposure to airborne particulates). The burden of asthma and COPD in a country can then be estimated by multiplying the AF by the number of deaths in the country. The disability associated with the diseases can also be estimated by multiplying the AF by disease-specific estimates of disability-adjusted life years (DALYs).
For the pneumoconioses, the proposed approach is simpler, because all cases are attributed to work (that is, the population AF is 100%). Therefore, the annual mortality burden can be estimated simply by counting the number of deaths from pneumoconioses per year in a given country. The disability associated with the pneumoconioses (in DALYs) is obtained from WHO published data.