ABSTRACT
Objective@#To evaluate the effects of exposure to ozone (O3) on sperm quality during different stages of spermatogenesis.@*Methods@#All 1 780 subjects attending to the Reproductive Medicine Center in Renmin Hospital of Wuhan University were recruited from April, 4, 2013 to June, 30, 2015. The subjects were living in Wuhan more than 3 months before attending to the program, aged 20 to 40 years. Semen quality (sperm concentration and sperm count) were measured according to standardized protocols. Corresponding daily 8 hours average concentration of O3, other polluted concentration, average temperature and relative humidity were collected in different time, including lag 0, 10, 70 and 90 d, and lag 0-9 d, lag 10-14 d, lag 70-90 d and lag 0-90 d. After controlling the age, BMI, education level and other confounders, generalized linear Model was used to investigate the association between O3 and sperm quality during different stages of spermatogenesis.@*Results@#Average daily concentration of O3 during the study period was (114.20±74.88) μg/m3 and the mean values of sperm concentration and count were (76.32±50.17) millions/ml and (164.77 ± 133.05) millions/sample, respectively. Exposure to O3 was associated with decreasing sperm concentration and count. For every 1 μg/m3 increase of O3, the decrease of sperm concentration during lag 10, lag 0-9 and lag 10-14 days exposure windows were 0.040 (95%CI: 0.004-0.077) millions/ml, 0.081 (95% CI: 0.003-0.158) millions/ml and 0.059 (95% CI: 0.001-0.116) millions/ml, respectively. And the decrease of sperm count during lag 10, lag 0-9 days exposure windows were 0.105 (95%CI: 0.008-0.202) millions/sample and 0.221 (95% CI: 0.016-0.426) millions/sample. After stratification, in the ozone concentration <P50 and ≥P50 groups, and the number of subjects in each exposure windows (lag 0-9, lag 10-14, lag 70-90, lag 0-90 days) were 887 and 893, 890 and 890, 895 and 885, 889 and 891, respectively. Compared with the high ozone concentration group, the effects of low group were more obvious. Furthermore, the effects of low concentration group was the most obvious during lag 10-14 days, for every 1 μg/m3 increase of O3, the decrease of sperm concentration was 0.249 (95% CI: 0.028-0.470) millions/ml. After sensitivity analysis, the effects of exposure to ozone on sperm concentration and sperm count remained relatively unchanged.@*Conclusion@#Our study suggested that exposure to O3 was significantly associated with decreasing semen quality in Wuhan. Moreover, the effects were more obvious during lag 0-9 and lag 10-14 days.
ABSTRACT
<p><b>OBJECTIVE</b>Using 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.</p><p><b>METHODS</b>Data 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.</p><p><b>RESULTS</b>Annual 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.</p><p><b>CONCLUSION</b>PM10 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.</p>