Heavy Metals in Air Emission and Assessment of Human Toxicity Footprint

Abstract

Objective : The purpose of this study is to propose the concept of the human toxicity (human cancer and non-cancer) footprint (µg 1,4 DCB (Dichlorobenzene) eqv./m3) using heavy metal concentration data in the air in Provincial and Metropolitan City governments. In addition, the final goal is to assess and compare the human carcinogenic toxicity footprint in Provincial and Metropolitan City Governments from 1991 to 2019.Method : To calculate the human carcinogenic toxicity footprint using heavy metal concentration in Provincial and Metropolitan City Governments, the ReCiPe 2016 life cycle impact assessment method in life cycle assessment (LCA) was used. For the human carcinogenic toxicity footprint calculation, the heavy metal concentration data in Provincial and Metropolitan City Governments are multiplied by the characterization factors of each heavy metal such as Pb, Cd, Cr, Ni, and As (Cu, Mn, Fe, Al, Ca, and Mg are not included in the air monitoring data) data (µg/m3). The unit of human carcinogenic toxicity footprint is shown in µg 1,4 DCB eqv. value.Results and Discussion : The results show that the heavy metal concentrations in Provincial and Metropolitan City governments were decreased significantly from 1991 to 2019. In the case of Pb, Incheon was decreased by about 2,124% (from 0.427 µg/m3 to 0.0192 µg/m3), and Busan was decreased by about 1,250% (from 0.2471 µg/m3 to 0.0183 µg/m3). In addition, in Cd’s case, Gwangju decreased by about 1,550% (from 0.0033 µg/m3 to 0.0002 µg/m3), and Incheon was decreased by about 1,071% (from 0.0082 µg/m3 to 0.0007 µg/m3). The results of human carcinogenic toxicity footprint in 1991 (early stage), 2005 (middle-stage), and 2019 (current) show that the average of human carcinogenic toxicity footprint was 8,478 µg 1,4 DCB eqv. in 1991, 5,545 µg 1,4 DCB eqv. in 2005 (about 53% decreased from 1991), and 1,997 µg 1,4 DCB eqv. in 2019 (about 178% decreased from 2005). In 2019, the human carcinogenic toxicity footprint results showed that Gyeongbuk had the highest value of 5,184 µg 1,4 DCB eqv. followed by Busan 3,929 µg 1,4 DCB eqv., Gyeongi 3,305 µg 1,4 DCB eqv., Seoul 2,184 µg 1,4 DCB eqv., Gwangwon 2,011 µg 1,4 DCB eqv. One of the reasons for the highest human carcinogenic toxicity footprint is the concentration of Cr and As, which have very high characterization factors.Conclusions : In this study, the human carcinogenic toxicity footprint using a heavy metal concentration in Provincial and Metropolitan City governments was proposed and calculated. Even though the heavy metal concentrations were decreasing, the number of measuring stations should be increased in each Provincial and Metropolitan City Government to improve the data quality and reduce the human carcinogenic toxicity impact by heavy metals.