Soil Intake,Respiration,and Skin Exposure Parameters In Environmental Health Risk Assessment

Exposure parameters are the key parameters to evaluate the exposure and health risks of environmental pollutants to people.Developed countries such as Europe,America,Japan and South Korea have carried out detailed and comprehensive studies on the exposure parameters of local populations,and issued their own/regional exposure parameter manuals.China has also carried out localized studies on exposure parameters,and produced the landmark results of"Handbook of Exposure Parameters in Chinese Populations",adult volumes and children volumes.However,the study of exposure parameters in China is not comprehensive enough,and some of the exposure parameters such as soil skin adhesion coefficient are directly referenced from the exposure parameter data in the United States.The human characteristics and life style of the foreign population are quite different from that of the Chinese population.If the exposure parameters are directly used to evaluate the exposure characteristics and behavior of the Chinese residents,the evaluation results will be quite uncertain.Therefore,starting with children’s soil intake,respiration rate,soil/dust skin adhesion coefficient and other typical exposure parameters,this paper carried out localized research to improve the exposure parameter system in China.Volunteers in this study 66 children in guangdong area as the research object,the collection of pairing food,feces,urine,and activity area of soil/dust samples,using the best tracer element method analyzing the tracer elements in the samples of aluminium(Al),barium(Ba),cerium(Ce),manganese(Mn),scandium(Sc),titanium(Ti),vanadium(V),yttrium(Y),The soil intake parameters of children were calculated by the model.The body characteristic parameters such as height and weight were obtained from 832 adults in Jiangsu and Guangdong.The respiratory rate of the population was calculated by using the energy assessment model.The soil/dust samples adhering to the arm of 40 adults in Jiangsu and Guangdong were wiped and collected,and the soil/dust samples from the surrounding activity area were collected.The tracer elements Al,Ba,Mn and V in the samples were analyzed.Combined with the skin surface area of the adult arm,the skin adhesion coefficient of soil/dust was calculated.The results showed that the soil intake of children in Guangdong ranged from 0 to 730.4 mg/d,the median was 106.5mg/d,and the 95th percentile was 383.3mg/d,which was 200 mg/d higher than the recommended value in the Chinese Exposure Parameters Manual(directly quoting the soil intake data of 95%of children in the United States).This indicates a significant increase in risk assessment using measured soil intake of local children compared to the recommended value of 200 mg/d in the Chinese Exposure Parametric Manual.The long-term range of the population in the survey area was 5 to 16.2 m~3/d,the median was 9.2 m~3/d,and the 95th percentile was 15.95 m~3/d,respectively.At rest,sitting,light activity,moderate physical activity,heavy physical activity and extreme physical activity,the short-term respiration volume was 4.07,4.89,6.11,16.28,24.42 and 40.70 L/min,respectively.The respiratory rate in Jiangsu was higher than that in Guangdong,and the respiratory rate in males was higher than that in females.The soil/dust skin adhesion coefficient of the arms of adults in the study area ranged from 0 to 869.44μg/cm~2,with the median and 95th percents being 115.1 and 236.4μg/cm~2,respectively,which were slightly higher than the American standard(87.2μg/cm~2).This study provides localized data of typical exposure parameters in oral,respiratory and skin exposure pathways,providing more accurate parameters for population environmental health risk assessment in China,and providing data support for the government to formulate technical guidelines to protect population health.