Increased Medical Emergency Calls During A Severe Air Pollution Episode In 2013 In Jinan, China

Introduction: In winter 2012-13, severe haze pollution affected major cities in central and eastern China, including Jinan. We investigated whether total medical emergency calls and calls for Central Nervous Systems Syndromes (CNS) increased during this episode and whether emergency calls were associated with particles with aerodynamic diameter ≤10um (PM10) in Jinan, China. Methods: Data on daily medical emergency calls (total and CNS calls) were obtained from Jinan Medical Emergency Center. CNS include dizziness, coma, convulsion, stroke, epilepsy, headache and paralysis. Analysis includes 2 time periods: 1) Dec 1, 2011- Feb 29, 2012 (lower pollution period), and 2) Dec 1, 2012- Feb 28, 2013 (high pollution period). Poisson time series models were used to estimate the change in emergency calls associated with heavy pollution period using an indicator variable, and with day-to-day variation in PM10 levels using a continuous variable. The models were adjusted for temporal trends, temperature, relative humidity and day of the week. Associations were estimated for multiple lag structures. Results: Air pollution levels were high in both the lower and higher air pollution periods with PM10 at 123 ug/m3 and 238 ug/m3, respectively. Compared to lower pollution period, daily number of total calls were significantly higher in the high pollution period (adjusted OR: 1.08; 95% CI: 1.05, 1.11), while the increase of CNS calls was marginally significant. We found positive associations between total calls and PM10 concentrations on lag 0- to lag 5- day. The strongest association was observed for lag 3-day [OR: 1.03; 95% CI: 1.01, 1.05, per IQR increment (121 ug/m3)]. The associations for calls for CNS showed similar patterns. Discussion: Air pollution levels are alarmingly high in winter in Jinan. Results indicate that substantial health benefits would result from efforts to prevent future severe episodes of haze pollution.