Specific sources of health risks caused by size-resolved PM-bound metals in a typical coal-burning city of northern China during the winter haze event

Potential health risks of inhaled toxic elements and risk sources during different COVID-19 lockdown stages in Linfen, China

“…People are exposed to health risks from toxic elements via three pathways: ingestion, inhalation, and dermal contact. Building on previous reports ( Agarwal et al, 2017 ; Huang et al, 2018 ; Li et al, 2017 ; Lin et al, 2020 ; Sulong et al, 2017 ), this study mainly considered the health risks of the selected toxic elements through inhalation exposure. Children and adults were considered separately owing to their different sensitivities to toxicity.…”

“…In this study, according to the studies from Diao et al (2021) , Huang et al (2018) , Lin et al (2020) , Sun et al (2021) , and Tian et al (2021) , the PMF and HR models were combined to assess the health risks associated with different emission sources through the following three steps: Step one: The source contributions to selected toxic elements levels are determined based on the PMF results as follows: where is the concentration of the j th element from the k th source in the i th sample (μg/m 3 ); denotes the contribution of the k th source to the i th sample (μg/m 3 ); and represents the mass fraction of the j th element for the k th source. Step two: The exposure doses of the selected toxic elements attributable to each source are calculated as follows: where is the average daily dose of the j th non-carcinogen from the k th source in the i th sample (mg/(kg·day)); is the average daily dose of the j th carcinogen from the k th source in the i th sample (mg/(kg·day)); and is the concentration of the j th toxic element from the k th source in the i th sample (mg/m 3 ).…”

“…Toxic elements, such as As, Mn, Cr, Zn, etc., in ambient PM 2.5 are able to induce adverse health effects owing to their bioavailability and bioaccumulation ( Chen and Lippmann, 2009 ; Gerlofs-Nijland et al, 2009 ; Zheng et al, 2016 ). Epidemiological studies found that the most toxic elements can play important roles in nerve damage ( Shen et al, 1996 ; Utsunomiya et al, 2004 ; Wang and Zhang, 2006 ), cardiopulmonary inflammation ( Joseph et al, 2015 ; Mukhtar and Limbeck, 2013 ), and respiratory infections ( Bollati et al, 2010 ; Ghio et al, 1999 ), and the health risks of toxic elements in ambient PM 2.5 ( Betha et al, 2014 ; Feng et al, 2016 ; Li et al, 2016 ; Lin et al, 2016 ) and critical risk sources ( Huang et al, 2018 ; Lin et al, 2020 ; Sun et al, 2021 ) have been widely studied.…”

“…Quantifying the health risks of toxic elements emitted at particular sources and identifying critical risk sources can support effective controls to promote public health ( Liu et al, 2021 ), especially for haze episodes. Huang et al (2018) , Lin et al (2020) , and Xie et al (2020) conducted the source-specific health risk analysis during haze episodes by combining the quantification of element-specific health risks and source apportionment and found that coal combustion and traffic-related emissions were the pivotal health risk sources. However, relatively few studies have adopted this approach.…”

“…Linfen is located in Shanxi Province and represents one of the most polluted cities in China ( Bai et al, 2021 ; Li et al, 2020a ). A prior study in Linfen suggested that coal combustion and traffic emissions were the dominant sources of non-cancer risk and cancer risk, respectively, during haze episodes ( Lin et al, 2020 ). After the outbreak of COVID-19, the Linfen government launched its highest level of lockdown measures since 26 January 2020 ( http://www.shanxi.gov.cn/yw/sxyw/202001/t20200125_762173.shtml ) until 10 February 2020 when the economy and production resumed ( http://nyj.linfen.gov.cn/contents/2019/496547.html ), which resulted in substantial changes in emission activities.…”