Pollution, sources, and bonding mechanism of mercury in street dust of a subtropical city, southern China

Spatial distribution of pollution characteristics and human health risk assessment of exposure to heavy elements in road dust from different functional areas of Zhengzhou, China

“…The samples were air dried for 5 days and passed through a 100-mesh polystyrene sieve (< 150 μm) to remove all debris, including stone, leaves, and hair (Lin et al 2019). The < 150-μm-diameter fraction was selected for analysis because these particles are capable of remaining in the atmosphere for considerable durations, (Kurt-Karakus 2012; Li et al 2015;Ma et al 2016b) and the proportion of heavy elements in the atmosphere is larger; so the highest possible risk to human health is considered.…”

“…Subsequently, parts of the sieved dust samples were transported to new self-sealing polyethylene bags and then stored at 4°C before analysis. According to previous assessments of the potential health risk of heavy elements to the human body (Men et al 2018b), seven typical metals (Li et al 2017;Lin et al 2019;Weerasundara et al 2018) and arsenic, an oncogenic metalloid (Rahman et al 2019;Škrbić et al 2018), which has some of the chemical properties of a metal, were chosen for determination. These eight elements are cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), zinc (Zn), and arsenic (As).…”

“…where RI is the sum of eight ecological risk factors (E i r ) of heavy elements; E i r is the monomial potential ecological risk factor for element i; T i r is the toxic response factor for a given material-1 for Zn; 2 for Cr; 5 for Cu, Ni, and Pb; 10 for As; 30 for Cd; and 40 for Hg (Hakanson 1980;Lin et al 2019;Soltani et al 2015;Zhao et al 2014); C i f is the contamination factor of element i and numerically equal to the PI; C i n and B i n are the mean concentration of element i and its reference geographical background value, respectively, which are the same variables defined in Eqs. 1and 2.…”

“…Children consume more food and water per unit of body weight, have a higher surface-to-volume ratio, grow at a faster rate, and have more rapidly changing hand-to-mouth behaviors and physiology changes than adults (USEPA 2009), which explains the significant difference of exposure risk between them (Shi et al 2011). To determine the public health risks of urban road dust, people are grouped into adults and children according to the following four exposed pathways: mouth ingestion absorption, inhalation of resuspended particles via nose, dermal or eye contact with dust (USEPA 2003), and inhalation of Hg vapor (Lin et al 2019). To assess the potential noncarcinogenic and carcinogenic risk of each element, the following equations were utilized to calculate:…”

“…Subsequently, more scholars considered the seasonal or spatial variation (Duan et al 2018;Škrbić et al 2018;Srikanth and Rao 2014;Zhang et al 2015) and determined that the meteorological condition and intensity of human activities changed with the change in seasons, which causes a variations in the pollution conditions and main contamination source in different seasons (Men et al 2018a). Moreover, road sediment particles polluted by heavy elements, especially fine particles, can be absorbed by adults or children by ingestion, inhalation via the mouth and nose, dermal adsorption, and inhalation of mercury vapor, which potentially or directly affects human health (Lin et al 2019;Torghabeh et al 2019). The integrated hazard index values for children at four locations in the city of Kuala Lumpur were calculated as > 1, which indicates a possible noncarcinogenic effect (Wahab et al 2020).…”