Organic Carbon(OC) And Elemental Carbon(EC) Inparticulate Matter Characteristics Andits Health Effects In Xingtai City

Particulate matter in the air has gradually become the focus of attention,of which PM_2.5is more important.Carbonaceous aerosols often account for the highest percentage of PM_2.5,which has high research significance.Xingtai has been a city that has repeatedly shown PM_2.5in recent years.The status and sources of carbonaceous aerosol pollution are of great significance.The average annual contents of PM_2.5,OC and EC in Xingtai area were 102.28μg·m^-3,20.3μg·m^-3,and 2.5μg·m^-3.Its annual concentration range is 12.61～278.49μg·m^-3,2.23μg·m^-3～77.59μg·m^-3,0.05μg·m^-3～13.15μg·m^-3.The particulate matter and carbonaceous components are higher than the observed concentrations in most cities at home and abroad,and the particulate matter and carbonaceous components show obvious seasonal characteristics.with the lowest concentration in summer and the highest concentration in winter,and their seasonal characteristics have a certain consistency.The summer concentration was 61.49μg·m^-3,8.4μg·m^-3,0.97μg·m^-3,and the winter concentration was150.34μg·m^-3,42.25μg·m^-3,5.48μg·m^-3.The proportion of carbonaceous components in particulate matter increased from 15%in summer to 32%.The daily changes of PM_2.5and carbonaceous components were found to be related to automobile exhaust emissions,weather conditions,coal combustion emissions,and human activities.In the same season,changes in the relevant values??on different days have a greater relationship with weather conditions.For example,the occurrence of several extreme values??in spring is related to sandstorms.The sharp decline in summer values??is related to continuous precipitation.Value changes in different seasons are related to coal emissions and pollutant transmission.The OC/EC ratio method was used to detect the source of the aerosol.It can be seen that the carbonaceous aerosols had a secondary transformation in four seasons,with different degrees.Spring,summer and autumn are dominated by biomass combustion and coal-fired emissions,and winter are dominated by coal-fired emissions.And the secondary organic carbon conversion rate is the highest in winter.This article analyzes and assesses the health and economic damage caused by atmospheric aerosol pollution.The number of people affected or killed by PM_2.5pollution is 141,600,accounting for 1.9%of the resident population of Xingtai in 2018.The economic loss caused by pollution is 2.4 billion,accounting for 11.2%of Xingtai’s GDP.The economic loss of premature death of lung cancer caused by PM_2.5pollution is the highest,at 905 million yuan.