Pollution Characteristics and Human Health Risk Assessment of Heavy Metals in Street Dust from a Typical Industrial Zone in Wuhan City, Central China.

This study aimed to assess the pollution levels, sources, and human health risks of heavy metals in street dust from a typical industrial district in Wuhan City, Central China. In total, 47 street dust samples were collected from the major traffic arteries and streets around Wuhan Iron and Steel (Group) Company (WISC) in Qingshan District, Wuhan. The concentrations of heavy metals (Cr, Mn, Ni, Zn, Fe, Cu, and Cd) in street dust were determined by atomic absorption spectroscopy. Results indicated that the mean concentrations of Zn (249.71 mg/kg), Cu (51.15 mg/kg), and Cd (0.86 mg/kg) in street dust were higher than their corresponding soil background values in Hubei Province. Heavy metal enrichment is closely related to urban transportation and industrial production. The pollution level of heavy metals in street dust was assessed using the geo-accumulation method (Igeo) and potential ecological risk assessment (PERI). Based on the Igeo value, Cr, Mn, Fe, and Ni showed no pollution, Zn and Cu showed light to moderate contamination, and Cd showed moderate contamination. The PERI values of heavy metals in street dust ranged between 76.70 and 7027.28, which represents a medium to high potential ecological risk. Principal component analysis showed that the sources of heavy metals in street dust were mainly influenced by anthropogenic activities. Among the studied metals, Cu, Cr, Zn, Fe, and Mn mainly come from industrial processes, while Ni and Cd come from traffic exhaust. The non-carcinogenic risk indexes of heavy metals for children and adults are ranked as Cr > Cu > Ni > Cd > Zn. The health risks to children through the different exposure pathways are higher than those for adults. Hand-to-mouth intake is the riskiest exposure pathway for non-carcinogenic risk. In addition, Cr, Ni, and Cd do not pose a carcinogenic risk for the residents.

Hazardous Heavy Metals Accumulation and Health Risk Assessment of Different Vegetable Species in Contaminated Soils from a Typical Mining City, Central China.

Heavy metal poisoning has caused serious and widespread human tragedies via the food chain. To alleviate heavy metal pollution, particular attention should be paid to low accumulating vegetables and crops. In this study, the concentrations of five hazardous heavy metals (HMs), including copper (Cu), chromium (Cr), lead (Pb), cadmium (Cd), and arsenic (As) were determined from soils, vegetables, and crops near four typical mining and smelting zones. Nemerow's synthetical pollution index (Pn), Potential ecological risk index (RI), and Geo-accumulation index (Igeo) were used to characterize the pollution degrees. The results showed that soils near mining and metal smelting zones were heavily polluted by Cu, Cd, As, and Pb. The total excessive rate followed a decreasing order of Cd (80.00%) > Cu (61.11%) > As (45.56%) > Pb (32.22%) > Cr (0.00%). Moreover, sources identification indicated that Cu, Pb, Cd, and As may originate from anthropogenic activities, while Cr may originate from parent materials. The exceeding rates of Cu, Cr, Pb, Cd, and As were 6.7%, 6.7%, 66.7%, 80.0%, and 26.7% among the vegetable and crop species, respectively. Particularly, vegetables like tomatoes, bell peppers, white radishes, and asparagus, revealed low accumulation characteristics. In addition, the hazard index (HI) for vegetables and crops of four zones was greater than 1, revealing a higher risk to the health of local children near the mine and smelter. However, the solanaceous fruit has a low-risk index (HI), indicating that it is a potentially safe vegetable type.

Assessment of Elemental Components in Atmospheric Particulate Matter from a Typical Mining City, Central China: Size Distribution, Source Characterization and Health Risk.

Atmospheric particulate matters in nine size fractions were sampled at Huangshi city, Hubei province. Elemental concentrations occurred unimodal size distribution for Zn, Pb and Ni, dimodal distribution for Ca, S, Fe and Ti, and trimodal distribution for Cl, K, Mn, Cu and Cr. Enrichment factor and principal component analysis identified the main sources from crustal material, biomass burning, waste incineration, vehicular and industrial emission. As for the non-carcinogenic health risk through inhalation, there were certain potential risks for Mn and Sb for children, and Pb for children and adults in PM2.5. It showed certain potential risks for Mn, Sb and Pb for children and adults in PM10. As for the carcinogenic health risk through inhalation, Cr in PM2.5 and Ni, Co and Cr in PM10 indicated unacceptable risk for children and adults. Meanwhile, Co and Ni in PM2.5 represented acceptable risk for children.

[Distribution, Sources and Risk Assessment of the PAHs in the Surface Sediments and Water from the Daye Lake].

8 surface sediments and 8 water samples were collected from the Daye Lake in August 2015.The 16 kinds of EPA control polycyclic aromatic hydrocarbons (PAHs) were analyzed by GC-MS.The results showed that the PAHs concentrations of surface sediments and water ranged from 35.94 ng·g-1 to 2032.73 ng·g-1 and from 27.94 ng·L-1 to 242.95 ng·L-1,with average contents of 940.61 ng·g-1 and 107.77ng·L-1,respectively.The distribution of PAHs in surface sediments indicated that the contents in the center samples were higher than those in the bank samples,but the water showed nearly the opposite tendency.The 4-5 rings high molecular weight PAHs were the main components in the surface sediments,and the 2,4 and 5 rings PAHs were given priority in water.Compared with the other domestic and oversea lakes,the PAHs pollution of the Daye Lake was at a moderate level.Source apportionment showed that the PAHs in surface sediments and water from the Daye Lake came from the combustion source,HWM-PAHs were the dominant part of the PAHs in the sediment,reflecting the sediment PAHs pollution under the effects of mining and smelting over a long period;All monomer PAHs and total PAHs content in sediment did not exceed the ERM and FEL limiting values,showing that there was no particularly serious ecological risk caused by PAHs in the surface sediments from the Daye Lake;the incremental lifetime cancer risks assessment showed that the uptake risk of PAHs in Daye Lake water through the ingestion and dermal absorption were both in the acceptable range recommended by the USEPA,but all sites had higher risk than the acceptable risk level recommended by the Sweden environmental protection agency and Royal society.The pollution of seven carcinogenic PAHs needs prevention and control.

[Pollution Characteristics and Risk Assessment of Heavy Metals in Water and Sediment from Daye Lake].

The surface water and surface sediments were collected from Daye Lake in April 2014. The concentrations of heavy metals were determined by atomic absorption spectroscopy. The pollution potential health risk and ecological risk of heavy metals in water and sediment were assessed by the health risk assessment model and the potential ecological risk index method. The results showed that the concentrations of the heavy metals (Ni, Cd, Cu and Pb) was 49.27 µg·L-1, 2.19 µg·L-1, 12.18 µg·L-1, 12.13 µg·L-1(water) and 78.46 mg·kg-1, 77.13 mg·kg-1, 650.13 mg·kg-1 and 134.22 mg·kg-1 (sediment). Enrichment coefficient indicated that the enrichment of Cd, Cu and Pb was more serious, especially the accumulation of Cd was the most obvious. Compared to typical lakes in China, the contents of heavy metals in water and sediment were relatively high. The spatial pollutant distribution of the heavy metals in water and sediment all presented that the concentrations of the heavy metals were relatively higher in east and west of Daye Lake, relatively more uniform in the middle, and their origins were mainly from human activities. The results of environmental risk indicated that the carcinogens and chemical non-carcinogens health risk values of heavy metals by drinking water pathway were 9.77E-08~1.63E-05a-1. Therefore, the pollution of Ni and Cd should be the primary control target for environmental health risk management. The descending order of pollution degree of four metals in sediment was Cd> Cu> Pb> Ni, and Cd was the main contributor of the potential ecological risk elements.

[Transportation and risk assessment of heavy metal pollution in water-soil from the Riparian Zone of Daye Lake, China].

Each 20 water samples and soil samples (0-10 cm, 10-20 cm) were collected from the riparian zone of Daye Lake in dry season during March 2013. Heavy metals (Cu, Ph, Cd, Zn) have been detected by flame atomic absorption spectrometric (FAAS). The results showed that the average concentrations of Cu, Pb, Cd, Zn in the water were 7.14, 25.94, 15.72 and 37.58 microg x L(-1), respectively. The concentration of Cu was higher than the five degree of the surface water environment quality standard. The average concentrations of Cu, Pb, Cd, Zn in soil(0-10 cm) were 108.38, 53.92, 3.55, 139.26 mg x kg(-1) in soil (10-20 cm) were 93.00, 51.72, 2.08, 171.00 mg x kg(-1), respectively. The Cd concentrations were higher than the three grade value of the national soil environment quality standard. The transportation of Pb from soil to water was relatively stable, and Zn was greatly influenced by soil property and the surrounding environment from soil to water. The transformation of heavy metal in west riparian zone was higher than that of east riparian zone. The potential environmental risk was relatively high. Cu, Pb, Cd, Zn were dominated by residue fraction of the modified BCR sequential extraction method. The overall migration order of heavy metal element was: Pb > Cu > Cd > Zn. There were stronger transformation and higher environmental pollution risk of Cu, Pb. The index of assessment and potential ecological risk coefficient indicated that heavy metal pollution in soil (0-10 cm) was higher than the soil (10-20 cm), Cd was particularly serious.