Urban air pollution and mental, eye, digestive, and musculoskeletal health problems in Toronto, Canada

Abstract

Exposure to air pollution has various adverse health effects. The present study investigates associations between ambient air pollution and the numbers of emergency department (ED) visits for mental and behavioural disorders, diseases of the eye and adnexa, diseases of the digestive system, and diseases of the musculoskeletal system and connective tissues. The associations of urban air pollutants with these ED visits in Toronto are studied for the period between 2004 and 2015 (total 4,292 days) using a time-stratified case-crossover study design. The statistical models apply conditional Poisson regressions using air pollutant concentrations lagged from 0 to 14 days. Strata by patients’ sex, age, and seasons are considered. For the mental and behavioural disorders, the estimated relative risks are 1.009 (95% confidence interval: 1.004, 1.014), 1.006 (1.000, 1.013), and 1.012 (1.005, 1.018), for all patients, as well as females and males. The values are reported for fine particulate matter lagged by 1 day, for a one interquartile range (IQR=6.5 mg/m3) increase in a concentration level. Analogous results for the diseases of the digestive system and nitrogen dioxide (lag 0, IQR = 8.8 ppb) are 1.032 (1.025, 1.039), 1.034 (1.026, 1.042), and 1.030 (1.022, 1.038), respectively. The considered large groups of health conditions have positive consistent associations with worsening urban air quality.

Keywords

• Air pollution
• Digestive system
• Dorsalgia
• Eye
• Mental health
• Urban