Effects of Air Pollution on Disease Respiratory: Structures Lag

Abstract

Objective: Little evidence is available on the association between ozone exposure and health in Campo Grande, Brazil. In this study, we aimed to examine the effects of surface ozone concentrations (O 3 ) on respiratory morbidity in Campo Grande, Brazil during the period from January 1 st , 2008 to December 31 st , 2011. Methods: Daily data on respiratory hospital admissions, O 3 , mean temperature, and relative humidity were collected at Campo Grande, Brazil. A Poisson time series model was used to examine the effects of O 3 on hospital admissions, while controlling for seasonality, long-term trend, temperature and relative humidity. A distributed lag non-linear function was used for O 3 , temperature, and relative humidity. We examined the effects of O 3 on different age groups (0 - 4 years, 5 - 60 years and >60 years). Results: The ozone-respiratory morbidity relationship was non-linear, with a threshold at 13 ppb (less than 25% percentile of ozone distribution). We estimated the relative risk of hospital admission at 75% percentile of O 3 distribution compared with associated with 25% of percentile of O 3 distribution. The O 3 effect on respiratory morbidity was delayed by two days and lasted for 4 days for all age groups except people aged 5 - 60 years. Children and the elderly were much more vulnerable to ozone pollution than people aged 5 - 60 years. Conclusions: This study suggests that ozone pollution has negative impacts on respiratory diseases in Campo Grande, Brazil. Children and the elderly were susceptible to O 3 exposure. These findings should be used to develop policies for protecting people from O 3 pollution.