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

Abstract

Levels of toxic elements in ambient PM 2.5 were measured from 29 October 2019 to 30 March 2020 in Linfen, China, to assess the health risks they posed and to identify critical risk sources during different periods of the COVID-19 lockdown and haze episodes using positive matrix factorization (PMF) and a health-risk assessment model. The mean PM 2.5 concentration during the study period was 145 μg/m 3 , and the 10 investigated toxic elements accounted for 0.31% of the PM 2.5 mass. The total non-cancer risk (HI) and total cancer risk (TCR) of the selected toxic elements exceed the US EPA limits for children and adults. The HI for children was 2.3 times that for adults for all periods, which is likely due to the high inhalation rate per unit body weight for children. While the TCR for adults was 1.7 times that of children, which is mainly attributed to potential longer exposure duration for adults. The HI and TCR of the toxic elements during full lockdown were reduced by 66% and 58%, respectively, compared to their pre-lockdown levels. The HI and TCR were primarily attributable to Mn and As, respectively. Health risks during haze episodes were significantly higher than the average levels during COVID-19 lockdowns, though the HI and TCR of the selected toxic elements during full-lockdown haze episodes were 68% and 17% lower, respectively, than were the levels during pre-lockdown haze episodes. During the study period, fugitive dust and steel-related smelting were the highest contributors to HI and TCR, respectively, and decreased in these emission sources contributed the most to the lower health risks observed during the full lockdown. There, the control of these sources is critical to effectively reduce public health risks.

Source apportionment of PM2.5 before and after COVID-19 lockdown in an urban-industrial area of the Lisbon metropolitan area, Portugal

“…Globally, these results are in line with other works, where PMF source apportionment generally revealed decreased contributions of vehicle emissions ( Cui et al, 2020 ; Cheng et al, 2022 ; Wang et al, 2021a ) and in some cases, also increased contributions of secondary inorganic aerosol ( Chang et al, 2022 ; Hong et al, 2021 ; Massimi et al, 2022 ).…”

“…The restriction measures reduced mobility and minimised anthropogenic activities in an unprecedented way around the world, creating a unique opportunity for assessing the effect of anthropogenic activities on air pollutants ( Querol et al, 2021 ) and on the associated health risks ( Aix et al, 2022 ; Cai et al, 2022 ). Many studies have reported that air quality has improved significantly during the city lockdowns, due to a drastic reduction of primary pollutants ( Collivignarelli et al, 2020 ; He et al, 2020 ; Rodríguez-Urrego and Rodríguez-Urrego, 2020 ; Sharma et al, 2020 ), while increased secondary pollutant levels were reported ( Hong et al, 2021 ; Wang et al, 2021a ; Chang et al, 2020 ; Zheng et al, 2020 ; Chang et al, 2022 ; Ma et al, 2022 ) , underlying the need to understand more deeply the formation mechanisms of secondary PM 2.5 .…”

“…There are some studies that report the comparison of PM 2.5 chemical composition and source contributions in the pre- and post-confinement periods ( Hong et al (2021) ; Cheng et al (2022) ; Cui et al (2020) ; Fatima et al (2022) ; Li et al (2021) ; Zheng et al (2020) ; Nguyen et al (2022) ; Wang et al (2021a) and Chang et al (2020) ), but only few are relative to European urban-industrial areas ( Massimi et al (2022) ; Hicks et al (2021) ) and none to Portugal, to the best of our knowledge.…”

Environmentally persistent free radicals in PM2.5 from a typical Chinese industrial city during COVID-19 lockdown: The unexpected contamination level variation

“… Liu et al (2021) , US EPA National Center for Environmental Assessment (1988) , Wang et al (2020) , Wang et al (2021) , Wang et al (2021) .…”

Dramatic changes in atmospheric pollution source contributions for a coastal megacity in North China from 2011 to 2020

“…The organic carbon (OC) and elemental carbon (EC) of samples during different years were determined using a thermal/optical carbon analyzer, based on the IMPROVE (in 2011IMPROVE (in -2012 and IMPROVE_A (in 2016 and 2019) thermal/optical reflectance protocol. The detailed instrumental information is listed in Table S5 and analysis procedures and quality controls are described in Text S1 in the supplemental materials as well as prior works from Liu et al, 2021a), , Wang et al (2021b), andTian et al, (2014). Hourly surface meteorological data including wind speed, wind direction, temperature, dewpoint, relative humidity, and pressure recorded at Qingdao Liuting International Airport were downloaded using the "worldMet" R package (Carslaw, 2017).…”