Cancer and wood-related occupational exposure in the Amazon region of Brazil

The occurrence of neoplasms, particularly nasal cavities and paranasal sinus tumors, has been associated with exposure to wood dust. The wood industry occupies an important place in the State of Pará, Brazil, where are located 90% of all the wood-related companies in the Brazilian Amazon market as a whole. The aim of this study was an exploratory analysis of cancer occurrence in woodworkers in the State of Pará. The proportional cancer incidence ratio (PCIR) was calculated for a group of 138 male woodworkers 20 years or older with a histological diagnosis of neoplasm treated at the Ofir Loyola Cancer Hospital in the state capital of Belém from 1991 to 1999. The cancer mortality odds ratio (CMOR) was also calculated in order to compare the cancer mortality among men 20 years or older residing in the State of Pará whose occupations involved wood exposure with that of men of the same age and place of residence but with different occupations. High and statistically significant PCIRs were observed for tumors of the oral cavity/pharynx, 2.44 (1.44-3.85), and stomach, 3.57 (2.41-5.10), in comparison to the population of Goiânia as well as in comparison to the population of Porto Alegre (oral cavity/pharynx, 1.97 (1.17-3.12), stomach, 3.12 (2.11-4.47)). We also observed a high and statistically significant PCIR for Hodgkin's disease, 5.30 (1.09-15.47), in comparison to the population of Goiânia. A CMOR of 8.86 (5.26-14.83) was observed for liver cancer. CMORs greater than 1 but not statistically significant were observed for neoplasms of the larynx. In agreement with the literature, woodworkers in Pará presented a high cancer incidence in specific anatomical sites. The results highlight the need for further epidemiological investigation to better evaluate this occupational exposure in the Amazon region.