OBJECTIVETo evaluate the acute effects of indoor and outdoor particulate matter on lung function and respiratory symptoms of college students in winter.

METHODSA panel of 37 college students aged 19-21 in Wuhan were included and the investigation was carried out from 12/23/2009 to 01/05/2010. Daily morning/evening forced expiratory volume in one second (FEV1) and respiratory symptoms (cough, phlegm and runny) were measured and reported by subjects, respectively. Meanwhile, daily data of indoors and outdoors PM10, PM2.5, temperature, and relative humidity were collected. Generalized Estimating Equations (GEEs) were used to estimate the association between particulate matters exposure and respiratory symptoms and FEV1).

RESULTSAverage daily concentrations of indoor, outdoor PM2.5 during the study period were (110.6 ± 42.3), (143.5 ± 51.2) µg/m³, (148.2 ± 43.2) and (239.1 ± 71.3) µg/m³ for indoor, outdoor PM10, respectively. Outdoor exposure to PM2.5 on lag 0 had little effect on evening FEV1). However, researchers observed a significant lagging effect (lag 1 d) and accumulative effect (lag 0-1 d and lag 0-2 d). A rise in the PM2.5 concentration of 10 µg/m³ resulted in the change of evening FEV1) of -0.28% (95% CI: -0.52%, -0.03%), -0.45% (95% CI: -0.81%, -0.08%) and -0.63% (95% CI: -1.15%, -0.11%), respectively. For respiratory symptoms of coughing up phlegm, 10 mg/m³ increase of indoor/outdoor PM2.5 concentration were associated with odds ratio of 1.18 (95% CI: 1.02-1.36) and 1.08 (95% CI: 0.97-1.19), respectively. Moreover, risk of coughing up phlegm increased with lagging time, and accumulative time of indoor and outdoor PM2.5 and PM10.

CONCLUSIONOur study suggested that short-term exposure to particulate matters in winter was significantly associated with acute changes of respiratory symptoms and FEV1) of college students in Wuhan. Moreover, the effects of particulate matters tended to be larger as the increase of lagged and accumulative days.

Air Pollutants ; Cough ; Forced Expiratory Volume ; Humans ; Humidity ; Mucus ; Particulate Matter ; Respiratory Tract Diseases ; Seasons ; Students ; Temperature

The effect of ambient particulate matters on human health is of great concern. Numerous epidemiological studies have revealed that particulate matters were associated with increased population mortality. Moreover, many studies found that season and temperature might modify the effect of particles on mortality. This paper summarized the potential effect modification of season and temperature and the possible mechanism, so as to provide certain evidence and reference for the future relevant studies.
Air Pollutants ; Epidemiologic Studies ; Humans ; Particulate Matter ; Seasons ; Temperature

OBJECTIVEUsing time-series analyses to determine the association between ambient air pollution and stroke mortality in Jiang'an District of Wuhan, China from 2003 to 2010.

METHODSData on daily stroke mortality for the period 2003 January 1 to 2010 December 31 was obtained from Jiang'an District Center for Disease Control and Prevention, Wuhan and data on relevant air pollution and meteorological factors from the local municipal environmental monitoring center and meteorology bureau of Wuhan, respectively. Application of a time-series analysis in generalized additive model was applied to evaluate the association between air pollution and stroke mortality.

RESULTSAnnual average concentrations of PM10, SO(2) and NO(2) during the study period were (115.0 ± 60.0), (50.2 ± 33.7), and (57.6 ± 25.3) µg/m³ respectively. The total stroke death was 9 204, including 4 495 women, and 7 628 people aged over 65-years old. In single-pollutant model, a 10 µg/m³ increase in previous day (lag 1 d) ambient pollutants was associated with 0.67% (95% CI: 0.25%-1.10%) excess risk in stroke mortality for PM10, 0.87% (95% CI: 0.13%-1.63%) excess risk for SO(2) and 2.07% (95% CI: 1.08%-3.07%) excess risk for NO(2), respectively. When co-pollutants were involved into the models, only NO(2) remained strongly associated with stroke mortality (β = 2.07, 95% CI: 1.08-3.07, P < 0.001). A 10 µg/m³, increase of NO(2) in lag 1 d was associated with 1.77% (95% CI: 0.54%-3.01%), 2.27% (95% CI: 0.98%-3.57%) and 2.00% (95% CI: 0.59%-3.43%) excess risk in stroke mortality, respectively, after adjusting for PM10, SO(2)th PM10 and SO(2) e-specific and gender-specific analyses showed that the association between ambient air pollution and stroke mortality was stronger in the elderly (≥ 65 years old) people and women. A 10 µg/m, increase of PM10, SO(2) NO(2) in lag 1 d was associated with excess stroke mortality of 0.97% (95% CI: 0.37%-1.57%), 1.73% (95% CI: 0.69%-2.78%) and 2.98% (95% CI: 1.59%-4.39%) for women, respectively and 0.94% (95% CI: 0.47%-1.42%), 1.06% (95% CI: 0.23%-1.90%) and 2.50% (95% CI: 1.40%-3.62%) for the elderly people (> 65 years old), respectively.

CONCLUSIONPM10 and gaseous pollutants (SO(2), NO(2)) were significant risk factors for acute stroke death, and people aged over 65-years old and women were more susceptible to the effect of ambient pollutants on stroke mortality.

Aged ; Air Pollutants ; Air Pollution ; China ; Environmental Monitoring ; Female ; Humans ; Models, Theoretical ; Mortality ; Nitrogen Dioxide ; Particulate Matter ; Risk ; Risk Factors ; Stroke ; Sulfur Dioxide