Pollution Characteristics and Health Risk Assessment of Airborne Heavy Metals Collected from Beijing Bus Stations
Abstract
:1. Introduction
2. Materials and Methods
2.1. Sampling and Analytical Methods
2.2. Pollution Level Analysis
2.3. Health Risk Assessment Model
Parameters | Definition | Unit | Carcinogenic Effects | Non-Carcinogenic Effects | References |
---|---|---|---|---|---|
ABS | Absorption Factor | -- | 0.01 | 0.01 | [34] |
AF | Adherence Factor | mg·cm2 | 0.07 | 0.07 | [33] |
AT | Averaging Time | days | 70 × 365 | ED × 365 | [31] |
BW | Body Weight | kg | 70 | 70 | [31] |
CF | Conversion Factor | kg·mg−1 | 10−6 | 10−6 | [31] |
ED | Exposure Duration | years | 50 | 40 | [31] |
EF | Exposure Frequency | day·year−1 | 250 | 250 | [22] |
F | Fraction of Time Spent at Bus Station in a Day | ‰ | 6.94 | 6.94 | [22] |
PEF | Particle Emission Factor | m3·kg−1 | 1.36 × 109 | 1.36 × 109 | [32] |
SA | Exposed Skin Surface Area | cm2·day−1 | 4350 | 4350 | [35] |
IRing | Ingestion Rate | mg·day−1 | 100 | 100 | [32] |
IRinh | Inhalation Rate | m3·day−1 | 20 | 20 | [36] |
RfDing (mg·kg−1·day−1) | RfDinh (mg·kg−1·day−1) | RfDder (mg·kg−1·day−1) | SFinh (kg·day·mg−1) | |
---|---|---|---|---|
Cd | 1.00 × 10−3 | 1.00 × 10−3 | 1.00 × 10−5 | 6.10 |
Cr | 3.00 × 10−3 | 2.86 × 10−5 | 6.00 × 10−5 | 4.10 × 10 |
Ni | 2.00 × 10−2 | 2.06 × 10−2 | 5.40 × 10−3 | 8.40 × 10−1 |
Co | 3.00 × 10−4 | 5.71 × 10−6 | 1.60 × 10−2 | 9.80 |
Cu | 4.00 × 10−2 | 4.02 × 10−2 | 1.20 × 10−2 | |
Mo | 5.00 × 10−3 | 4.95 × 10−3 | 1.90 × 10−3 | |
Pb | 3.50 × 10−3 | 3.52 × 10−3 | 5.25 × 10−4 | |
V | 5.04 × 10−3 | 7.00 × 10−3 | 7.00 × 10−5 | |
Zn | 3.00 × 10−1 | 3.00 × 10−1 | 6.00 × 10−2 |
3. Results and Discussion
3.1. Heavy Metals Concentrations in Dustfall
Elements | Min (mg·kg−1) | Max (mg·kg−1) | Mean (mg·kg−1) | Standard Deviation | Coefficient Variation | Skewness | Kurtosis | Background Value |
---|---|---|---|---|---|---|---|---|
Cd | 0.90 | 6.72 | 2.46 | 1.06 | 0.43 | 1.70 | 5.04 | 0.07 |
Co | 10.90 | 18.72 | 14.65 | 1.91 | 0.13 | 0.10 | −0.68 | 17.00 |
Cr | 85.90 | 219.71 | 128.13 | 28.60 | 0.22 | 1.19 | 2.01 | 68.10 |
Cu | 75.89 | 523.66 | 206.94 | 106.61 | 0.52 | 1.25 | 1.36 | 23.60 |
Mo | 2.89 | 38.59 | 8.45 | 5.71 | 0.67 | 3.44 | 16.91 | 4.10 |
Ni | 30.66 | 95.85 | 56.68 | 16.00 | 0.28 | 0.84 | −0.11 | 29.00 |
Pb | 40.26 | 174.39 | 107.98 | 28.89 | 0.27 | 0.11 | 0.08 | 25.40 |
V | 53.38 | 100.22 | 78.96 | 9.84 | 0.12 | −0.37 | 0.20 | 79.20 |
Zn | 234.62 | 982.37 | 525.17 | 174.36 | 0.33 | 0.56 | 0.33 | 102.60 |
3.2. Pollution Assessment of Heavy Metals in Dustfall
3.3. Spatial Distribution of Heavy Metals in Dustfall
3.4. Potential Health Risk Assessment
Cd | Cr | Ni | Co | Cu | Mo | Pb | V | Zn | ||
---|---|---|---|---|---|---|---|---|---|---|
ADing * | Min | 6.09 × 10−9 | 5.83 × 10−7 | 2.08 × 10−7 | 7.40 × 10−8 | 5.15 × 10−7 | 1.96 × 10−8 | 2.73 × 10−7 | 3.63 × 10−7 | 1.59 × 10−6 |
Max | 4.56 × 10−8 | 1.49 × 10−6 | 6.51 × 10−7 | 1.27 × 10−7 | 3.56 × 10−6 | 2.62 × 10−7 | 1.18 × 10−6 | 6.81 × 10−7 | 6.67 × 10−6 | |
Mean | 1.67 × 10−8 | 8.70 × 10−7 | 3.85 × 10−7 | 9.95 × 10−8 | 1.41 × 10−6 | 5.74 × 10−8 | 7.33 × 10−7 | 5.36 × 10−7 | 3.57 × 10−6 | |
ADinh * | Min | 8.95 × 10−13 | 8.58 × 10−11 | 3.06 × 10−11 | 1.09 × 10−11 | 7.58 × 10−11 | 2.89 × 10−12 | 4.02 × 10−11 | 5.33 × 10−11 | 2.34 × 10−10 |
Max | 6.71 × 10−12 | 2.19 × 10−10 | 9.57 × 10−11 | 1.87 × 10−11 | 5.23 × 10−10 | 3.85 × 10−11 | 1.74 × 10−10 | 1.00 × 10−10 | 9.81 × 10−10 | |
Mean | 2.46 × 10−12 | 1.28 × 10−10 | 5.66 × 10−11 | 1.46 × 10−11 | 2.07 × 10−10 | 8.44 × 10−12 | 1.08 × 10−10 | 7.88 × 10−11 | 5.24 × 10−10 | |
ADinh ** | Min | 6.40 × 10−13 | 6.13 × 10−11 | 2.19 × 10−11 | 7.77 × 10−12 | |||||
Max | 4.79 × 10−12 | 1.57 × 10−10 | 6.84 × 10−11 | 1.34 × 10−11 | ||||||
Mean | 1.76 × 10−12 | 9.14 × 10−11 | 4.04 × 10−11 | 1.05 × 10−11 | ||||||
Adder * | Min | 1.85 × 10−10 | 1.78 × 10−8 | 6.34 × 10−9 | 2.25 × 10−9 | 1.57 × 10−8 | 5.97 × 10−10 | 8.32 × 10−9 | 1.10 × 10−8 | 4.85 × 10−8 |
Max | 1.39 × 10−9 | 4.54 × 10−8 | 1.98 × 10−8 | 3.87 × 10−9 | 1.08 × 10−7 | 7.98 × 10−9 | 3.61 × 10−8 | 2.07 × 10−8 | 2.03 × 10−7 | |
Mean | 5.10 × 10−10 | 2.65 × 10−8 | 1.17 × 10−8 | 3.03 × 10−9 | 4.28 × 10−8 | 1.75 × 10−9 | 2.23 × 10−8 | 1.63 × 10−8 | 1.09 × 10−7 | |
ADtot | Min | 6.28 × 10−9 | 6.01 × 10−7 | 2.15 × 10−7 | 7.63 × 10−8 | 5.31 × 10−7 | 2.02 × 10−8 | 2.82 × 10−7 | 3.74 × 10−7 | 1.64 × 10−6 |
Max | 4.70 × 10−8 | 1.54 × 10−6 | 6.71 × 10−7 | 1.31 × 10−7 | 3.66 × 10−6 | 2.70 × 10−7 | 1.22 × 10−6 | 7.01 × 10−7 | 6.87 × 10−6 | |
Mean | 1.73 × 10−8 | 8.97 × 10−7 | 3.97 × 10−7 | 1.03 × 10−7 | 1.45 × 10−6 | 5.92 × 10−8 | 7.56 × 10−7 | 5.53 × 10−7 | 3.68 × 10−6 |
Cd | Cr | Ni | Co | Cu | Mo | Pb | V | Zn | HI | ||
---|---|---|---|---|---|---|---|---|---|---|---|
HQing | MIN | 6.09 × 10−6 | 1.94 × 10−4 | 1.04 × 10−5 | 2.47 × 10−4 | 1.29 × 10−5 | 3.92 × 10−6 | 7.81 × 10−5 | 7.19 × 10−5 | 5.31 × 10−6 | 6.30 × 10−4 |
MAX | 4.56 × 10−5 | 4.97 × 10−4 | 3.25 × 10−5 | 4.24 × 10−4 | 8.89 × 10−5 | 5.24 × 10−5 | 3.38 × 10−4 | 1.35 × 10−4 | 2.22 × 10−5 | 1.64 × 10−3 | |
MEAN | 1.67 × 10−5 | 2.90 × 10−4 | 1.92 × 10−5 | 3.32 × 10−4 | 3.51 × 10−5 | 1.15 × 10−5 | 2.10 × 10−4 | 1.06 × 10−4 | 1.19 × 10−5 | 1.03 × 10−3 | |
HQinh | MIN | 8.95 × 10−10 | 3.00 × 10−6 | 1.49 × 10−9 | 1.91 × 10−6 | 1.89 × 10−9 | 5.83 × 10−10 | 1.14 × 10−8 | 7.62 × 10−9 | 7.81 × 10−10 | 4.93 × 10−6 |
MAX | 6.71 × 10−9 | 7.67 × 10−6 | 4.65 × 10−9 | 3.27 × 10−6 | 1.30 × 10−8 | 7.79 × 10−9 | 4.95 × 10−8 | 1.43 × 10−8 | 3.27 × 10−9 | 1.10 × 10−5 | |
MEAN | 2.46 × 10−9 | 4.47 × 10−6 | 2.75 × 10−9 | 2.56 × 10−6 | 5.14 × 10−9 | 1.71 × 10−9 | 3.06 × 10−8 | 1.13 × 10−8 | 1.75 × 10−9 | 7.09 × 10−6 | |
HQder | MIN | 1.85 × 10−5 | 2.96 × 10−4 | 1.17 × 10−6 | 1.41 × 10−7 | 1.31 × 10−6 | 3.14 × 10−7 | 1.59 × 10−5 | 1.58 × 10−4 | 8.09 × 10−7 | 4.92 × 10−4 |
MAX | 1.39 × 10−4 | 7.57 × 10−4 | 3.67 × 10−6 | 2.42 × 10−7 | 9.02 × 10−6 | 4.20 × 10−6 | 6.87 × 10−5 | 2.96 × 10−4 | 3.39 × 10−6 | 1.28 × 10−3 | |
MEAN | 5.10 × 10−5 | 4.42 × 10−4 | 2.17 × 10−6 | 1.89 × 10−7 | 3.57 × 10−6 | 9.20 × 10−7 | 4.25 × 10−5 | 2.33 × 10−4 | 1.81 × 10−6 | 7.77 × 10−4 | |
HIt | MIN | 2.46 × 10−5 | 4.93 × 10−4 | 1.16 × 10−5 | 2.49 × 10−4 | 1.42 × 10−5 | 4.24 × 10−6 | 9.40 × 10−5 | 2.30 × 10−4 | 6.12 × 10−6 | 1.13 × 10−3 |
MAX | 1.85 × 10−4 | 1.26 × 10−3 | 3.62 × 10−5 | 4.27 × 10−4 | 9.79 × 10−5 | 5.66 × 10−5 | 4.07 × 10−4 | 4.31 × 10−4 | 2.56 × 10−5 | 2.93 × 10−3 | |
MEAN | 6.77 × 10−5 | 7.36 × 10−4 | 2.14 × 10−5 | 3.34 × 10−4 | 3.87 × 10−5 | 1.24 × 10−5 | 2.52 × 10−4 | 3.40 × 10−4 | 1.37 × 10−5 | 1.82 × 10−3 | |
RI | MIN | 3.90 × 10−2 | 2.51 × 10−9 | 1.84 × 10−11 | 7.62 × 10−11 | ||||||
MAX | 2.92 × 10−11 | 6.43 × 10−9 | 5.74 × 10−11 | 1.31 × 10−10 | |||||||
MEAN | 1.07 × 10−11 | 3.75 × 10−9 | 3.40 × 10−11 | 1.02 × 10−10 |
4. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Zheng, X.; Zhao, W.; Yan, X.; Shu, T.; Xiong, Q.; Chen, F. Pollution Characteristics and Health Risk Assessment of Airborne Heavy Metals Collected from Beijing Bus Stations. Int. J. Environ. Res. Public Health 2015, 12, 9658-9671. https://doi.org/10.3390/ijerph120809658
Zheng X, Zhao W, Yan X, Shu T, Xiong Q, Chen F. Pollution Characteristics and Health Risk Assessment of Airborne Heavy Metals Collected from Beijing Bus Stations. International Journal of Environmental Research and Public Health. 2015; 12(8):9658-9671. https://doi.org/10.3390/ijerph120809658
Chicago/Turabian StyleZheng, Xiaoxia, Wenji Zhao, Xing Yan, Tongtong Shu, Qiulin Xiong, and Fantao Chen. 2015. "Pollution Characteristics and Health Risk Assessment of Airborne Heavy Metals Collected from Beijing Bus Stations" International Journal of Environmental Research and Public Health 12, no. 8: 9658-9671. https://doi.org/10.3390/ijerph120809658