Lung cancer risk assessment for workers exposed to polycyclic aromatic hydrocarbons in various industries

Millions of workers are exposed to carcinogenic polycyclic aromatic hydrocarbon (PAH) mixtures. The toxicity of PAH mixtures is variable and depends on the composition of the mixture, which is related to the emission sources. Although several indicators exist, the cancer risk estimation associated with occupational exposure to PAHs is poorly known.

To assess the risk of lung cancer associated with PAHs in several industries using the atmospheric concentrations of benzo[a]pyrene (BaP) as a proxy.

A total of 93 exposure groups belonging to 9 industries were investigated. Eight indicators found in the literature were compared to assess risks. A consensual indicator was used to estimate lung cancer risks.

Approximately 30% of the exposure groups were above the maximal risk level of the European Union (10^-4). The risk probabilities were >10^-3 for coke and silicon production; >10^-4 for the manufacturing of carbon products and aluminum production; >10^-5 for foundries and combustion processes; >10^-6 for the use of lubricating oils and engine exhaust emissions; and >10^-7 for bitumen. The risk probabilities were highly variable within industries (from 1 to 1000 likelihood). A total of 27 (95% CI: 0.1-54) contemporary additional lung cancer cases could be expected per year in the French exposed population based on estimations using published data.

This study provides an overview of cancer risk estimation in many industries. Despite efforts and changes that had been made to decrease risks, PAHs remain a sanitary threat for people exposed to these pollutants in occupational environments.