Effect Of PM_2.5 On Population Mortality In Jinan

BackgroundAir pollution has become one of the largest public health problems in the world,and exerts a profound impact on the public health for global population.Especially,Jinan,the capital city of Shandong Province,is one of the typical air pollution cities.Air pollution has been one of the highest risk factors for mortality and disability worldwide.Breathing contaminated air increased the risk of heart disease,chronic respiratory disease,lung infections and even cancer.Those residents living in areas with heavy air pollution for a long time may differ from other areas in terms of the personal health situation,fitness and personal protective measures.Therefore,there is an urgent need to increase attention to the related health conditions of pollutant exposure in highly polluted cities.In recent years,affected by factors such as global climate change,frequent extreme weather,atmospheric pollution,and global warming,the morbidity and mortality of related diseases have increased year by year,let alone the modification of meteorological factors on the health effects of pollutants.Objectives1.Assess the impact of exposure of PM2.5 on non-accidental mortality,cardiovascular disease mortality,and respiratory disease mortality in Jinan.2.Establish a model to analyze the non-linear relationship between PM2.5 exposure and related mortality,and the distribution of short-term lag effects in high-polluted area.3.Explore the threshold of relationships between PM2.5 exposure and non-accidental mortality,cardiovascular disease mortality and respiratory disease mortality in Jinan.Further provide a basis for formulating public health policies in high-pollution areas and ensuring the health of the population.4.Investigate the effect modification of other meteorological factors on effect of the exposure of PM2.5 on related mortality,and contribute to a more accurate evaluation of the effects of PM2.5 exposure.MethodsBased on the daily monitoring data of meteorological factors,air pollutants and related mortality from Jinan City,Shandong Province from 2011 to 2017,a descriptive analysis of the basic situation in the study area and period was conducted.Spearman rank correlation was used to analyze the relationship between each pollutant and meteorological factors.First,a generalized additive model(GAM)was established and avoided the inclusion of two variables which were too correlated.After co-linearity tests were performed,the relationship between PM2.5 exposure and related mortality was explored.In order to explore whether there is lag effect and non-linearity,a distributed lag non-linear model(DLNM)was established to evaluate the non-linearity,lag effect,and harvesting effect of PM2.5 on non-accidental mortality,cardiovascular disease mortality,and respiratory disease mortality.Based on the DLNM,the existence of breakpoint is explored to evaluate the threshold effect.In order to ensure the reliability of the research results,we carry out a sensitivity analysis and use two methods to change the longest lag days and change the parameters of the basis function of cross-basis function to verify the stability of the results.Then,based on the GAM,the interaction terms of PM2.5 and meteorological factors were included to explore the interaction between PM2.5 and meteorological factors,and further based on the DLNM,stratified analysis for each meteorological factor was performed.And the effect modification of daily average temperature,relative humidity and average wind speed on the death effect of PM2.5 was explored.ResultsThere was a non-linear positive correlation between related mortality and PM2.5.Average PM2.5 concentration levels for non-accidental mortality(RR=1.12,95%CI:1.06-1.19),cardiovascular disease mortality(RR=1.16,95%CI:1.10-1.22)and respiratory disease mortality(RR=1.19,95%Cl:1.02-1.38)all had the highest impact on the day(lag0),and had a harvest effect on the model of cardiovascular disease mortality.In Jinan,no safety threshold with a zero effect level was found,but there was a saturation point.For non-accidental mortality,the saturation point is 233?g/m3,and for both cardiovascular and respiratory disease mortality,the saturation point were 249????g/m3.In further interaction and effect modification analysis,it was found that low temperature,low relative humidity,and high wind speed could promote the effect of PM2.5 on mortality synergistically.ConclusionsWith the rapid development of economy and the acceleration of urbanization in China,air pollution has gradually intensified since 2013,and those residents who lived in areas with severe air pollution for a long time may have different personal health indication,fitness and personal protection measures.This research aims at the current research status and existing problems,and explores the threshold effect of pollutants based on time series data in Jinan during 2011-2017,and provides a basis for formulating public health policies,which will be beneficial to the health of the population while saving greater costs and has important academic value and practical significance.The research results emphasize the need to continuously strengthen the control of particulate pollutants,and implement air quality standard for heavily polluted areas in accordance with local conditions.At the same time,for areas with severe pollution,it is advisable to strengthen individual protection to reduce saturation points and control the concentration of pollutants as much as possible,which will greatly save costs and benefit the public.