Study On Air Pollution Characteristics And Health Risk Assessment In Handan

In this study,the data of particle chemical composition in PM_2.5?2013-2015?,the data of PM₁₀,PM_2.5,PM_1.0,and gaseous pollutants in heating season?2015-2016?located at Hebei University of Engineering in Handan were used for statistical analysis.The main factor analysis method and enrichment factor method were used to analyze the sources of particulate pollution.International Agency for research on cancer?IARC?and Environmental Protection Agency?EPA?integrated risk information database?IRIS?provides a model to health risk assessment for us.We use this model to evaluate the carcinogenic risk and non carcinogenic risk of respiration,digestive tract and skin contact in three ways of heavy metals in PM_2.5 from 2013 to 2015 in Handan.The main conclusions are as follows:?1?The average concentration of PM₁₀,PM_2.5,PM_1.0 durning thr heating season in Handan were 227.1,131.7,and 103.7?g·m^-3,respectively.The maximum concentration of hour date of PM₁₀,PM_2.5,PM_1.0 reached 1456.3,1196.9,and 1079.2?g·m^-3,respectively.The mean values of PM₁/PM_2.5 and PM_2.5/PM₁₀ were 0.79 and0.56,respectively.Most of the inhalable particles were fine particles.Most of the fine particles were submicron particles.The mass concentrations of PM₁₀,PM_2.5,and PM_1.0were highest at 9:00 in the morning and lowest at 17:00 p.m.The average concentrations of OC,EC,SO₄²⁺and NO₃^-in PM_2.5 durning the heating season of Handan were 27.1,5.4,27.1,and 22.6?g·m^-3,respectively.The concentration of OC was highest at 2:00 in the evening and lowest at 17:00 in the afternoon.The concentration of EC changed steadily,it was highest at 9:00 in the morning and lowest at 17:00 in the afternoon.The concentration of SO₄²⁺reaches its peak around 11:00 and lowest at around 18:00 in the afternoon.The concentration of NO₃^-was highest around0:00 in the evening and reached its minimum at around 15:00 p.m..SOC pollution was serious during the heating season in Handan,and the average mass concentration was17.9?g·m^-3.The diurnal variation of SOC concentration was higher than that of daytime,and the maximum value appeared at around 2:00 in the evening.The concentration of SO₄²⁺and NO₃^-in PM_2.5 was affected obviously by gaseous pollutants and meteorological factors in the heating season of Handan.?2?The level of water soluble ion pollution tended to decrease gradually from2013 to 2015 in Handan.The concentration of water-soluble ions was higher in autumn and winter than in spring and summer.In 2013,spring,summer,autumn and spring,summer,autumn and winter in 2015,PM_2.5 was acidic on the whole,and PM_2.5 was alkaline in the rest of the three year.Major water-soluble ions of spring,summer,and autumn in 2014 were in the form of NH₄NO₃,?NH₄?₂SO₄,and NH₄Cl.Major water-soluble ions of winter in 2014 and all years of 2013 and 2015 were in the form of NaCl,KCl,NH₄NO₃,HNO₃,and?NH₄?₂SO₄.OC declined first and then increased,and EC increased first and then decreased from 2013 to 2015.From 2013 to 2015,the seasonal concentrations of OC and EC were winter>autumn>spring>summer.The correlation between OC and EC was good in three years.The correlation between OC and EC was the highest in winter.From 2013 to 2015,the carbon composition pollution sources mainly came from the winter coal combustion,as well as the annual emissions of gasoline vehicles and biomass combustion,and diesel exhaust and road dust also occupied a considerable proportion.The pollution of diesel exhaust in Handan decreased year by year from 2013 to 2015.The average concentration level of inorganic elements in three years from 2013 to 2015 were Ca>K>Fe>Zn>Pb>Mn>Ti>Ba>Cu>Cr>V>Co.The total mass concentration of main inorganic elements in PM_2.5 showed a downward trend from 2013 to 2015.Cu,Zn and Pb mainly come from human sources,Ti,K,Ca,V,Cr,Mn,Co and Ba,mainly from natural sources.The binding modes of major water-soluble ions SO₄^2-,NO₃^-and NH₄⁺of PM_2.5 in Handan tended to be biased?NH₄?₂SO₄ and NH₄NO₃.The emission sources in Handan had tended to be stationary sources in the three years.Handan was greatly affected by traffic sources,coal-fired sources and industrial emissions.?3?Cr,Ni,Cu,Zn,As,Pb and Cd had no risk of non carcinogenic to human body under three pathways of body breathing,oral intake and skin contact from 2013 to2015 in Handan.Cr,Ni,Cu,Zn,As,Pb and Cd had no carcinogenic risk to human body under three pathways of body breathing,oral intake and skin contact from 2013to 2015 in Handan.The carcinogenic risk and non carcinogenic risk of Cr,Ni,Cu,Zn,As,Pb and Cd were within the acceptable range of the human body.Cr was needed to be noticed and its carcinogenic risk value was large which was close to acceptable level of human body(10^-6).The carcinogenic risk of Cr showed an upward trend year by year and had a potential cancer risk.