The Study On The Relationship Between Individual PM_2.5 Exposure And Respiratory System Related Biomarkers

Objective To explore the relationship between both individual PM_2.5 exposure and lung function and inflammatory factors in the elderly.Provide technical support for conducting population health risk assessment,disease prevention and formulating relevant health protection policies.Method A panel study was conducted on elderly aged 60-69 years,they lived in the community for at least 2 years and had a regular rest schedule,fixed actitvity scope,good cooperation degree.We excluded the elderly with smoking,intemperance,obesity,and other basic diseases.A total of 76 subjects were eligible.The study was conducted from September 10,2018 to January 21,2019.We measured personal PM_2.5exposure in 3 days by Micro PEM(TM).We collected basic information,living environment,lifestyle,health status and main symptoms through a series of questionnaires.Subjects were given a uniform diet from 2 days before the start of individual PM_2.5 exposure monitoring to the end of monitoring.They were requested to have five monthly lung function and blood measurements after monitoring.We tested IL-6,IL-8,IL-10 and IL-1?concentration in plasma samples by the technology of multiplex biomarker detection(xMAP(?)).Excel was used to establish the database,and R3.6.1 software"lme4"package was used for data analysis.Linear mixed effect models were applied to analyze the association between PM_2.5 and health indicator after controlling covariates such as season,average temperature,relative humidity and individual characteristics.Results 76 subjects with a mean age of 64.97±2.80 years,of whom 50.0%were male.The median and IQR of personal PM_2.5 exposure concentration were 40.00 and 36.0?g/m³,ranging from 6.0 to 309.6?g/m³.PM_2.5exposure was divided into intraday lags of 0d(Lag 0),1d(Lag 1),2d(Lag2)and cumulative lags of 6h(lag0-5),12h(lag0-11),24h(lag0-23),48h(lag0-47)and 72h(lag0-71).The association between PM_2.5 exposure and lung function was statistically non-significant.PM_2.5 was found to have lag effects on inflammatory factors.In total,PM_2.5 exposure was significantly associated with decreased levels of IL-8(lag0 and 2 days,0-48 and 0-72 h),IL-10(lag0and 1days,0-12,0-48 and 0-72h),IL-1?(lag0 and 1days).For each 10?g/m³ increase in PM_2.5 concentration of lag0d and lag2d,IL-8 would decrease in 1.31%(95%CI:-2.17,-0.39%)and 1.41%(95%CI:-2.43,-0.37%)respectively.For each 10?g/m³ increase in PM_2.5 concentration of lag0d and lag1d,IL-10 would decrease in 12.16%(95%CI:-3.18,-1.11%)and 1.41%(95%CI:-2.72,-0.18%)respectively.For each 10?g/m³ increase in PM_2.5 concentration of lag0d and lag1d,IL-1?would decrease in 1.77%(95%CI:-2.61,-0.87%)and 1.89%(95%CI:-2.93,-0.84%)respectively.Subgroup analysis found that males,people who were overweight,people who were not had postsecondary degree and people whose family incomes below 80 thousand have an effect-modifying effect on the association of PM_2.5 and lung function,the decrease of lung function were associated with increasing in PM_2.5.Females,people with a normal body mass indexand,people who were not had postsecondary degree and people whose family incomes below 80thousand have an effect-modifying effect on the association of PM_2.5 and inflammatory factors,the decrease of inflammatory factors were associated with increasing in PM_2.5.Conclusions Short-term exposure to PM_2.5 cause significant changes in inflammatory indicators in healthy elderly,women were more susceptible.The changes in lung function affected by short-term exposure to PM_2.5 in healthy elderly were not significant,but men and overweight people were more sensitive to PM_2.5 exposure.It is suggested to strengthen the health education of health protection knowledge of air pollution in the community,so as to enhance the health protection awareness of the residents.