Proximity to wood factories and hospitalizations for respiratory diseases in children

BACKGROUND: Exposure to air pollutants emitted by wood industries has been associated with increased prevalence of respiratory and irritation symptoms. OBJECTIVES: To study whether proximity to wood industries was associated with risk of hospitalization for respiratory diseases in children. METHODS: In December 2006, the large majority of the children (3-14 years) living in the Viadana district (Northern Italy) were surveyed through a parental questionnaire (n=3854). Hospital discharge records for respiratory diseases (2002-2006) were obtained from the local Health Unit. The children were geocoded and the distance from their home/school to the wood industries was used as exposure indicator. Poisson regression models were used to assess the association between the distance and hospitalizations. RESULTS: The hospitalization rates for respiratory diseases increased with proximity to the wood industries: they were 7.55 (95% CI 5.58, 10.22) ×1000 person-year for those who lived far from any wood industry, 11.84 (95% CI 8.87, 15.81) ×1000 person-year for those <2km from the small wood factories and 16.61 (95% CI: 13.57, 20.33) ×1000 person-year for those living within 2km from the two big chipboard industries. CONCLUSIONS: Proximity to wood industries is associated with a higher risk of hospitalization for respiratory diseases and respiratory symptoms in children. Studies with direct measures of exposure are needed and a follow-up of exposed population is advisable.