Removal Efficiency and Risk Assessment of Polycyclic Aromatic Hydrocarbons in a Typical Municipal Wastewater Treatment Facility in Guangzhou, China
Abstract
:1. Introduction
2. Materials and Methods
2.1. Chemicals
2.2. Wastewater Treatment Plant
2.3. Sampling
2.4. Chemical Analyses
2.5. Quality Assurance and Quality Control
2.6. Toxicity Assessment
2.6.1. Toxic Equivalent Quantity
2.6.2. Health Risk
3. Results
3.1. PAHs in Dissolved Phase
3.1.1. Comparison between Different Dates
3.1.2. Concentrations of PAHs
3.1.3. Removal Efficiencies of PAHs
3.2. PAHs in Dewatered Sludge Samples
3.3. PAHs Source Analysis by Diagnostic Ratios
3.4. Risk Assessment
3.4.1. Effluent
3.4.2. Dewatered Sludge
4. Discussion
5. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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Date | Stage | 2-Rings | 3-Rings | 4-Rings | ∑LMW PAHs | ∑HMW PAHs | ∑PAHs | ||||
---|---|---|---|---|---|---|---|---|---|---|---|
NAP | ANE | ANA | FLU | PYR | BaA | CHR | |||||
23 November | IN | 335.66 | 21.06 | 50.82 | 56.49 | 19.14 | 48.06 | 23.13 | 464.03 | 90.33 | 554.36 |
EG | 85.15 | 19.78 | 38.33 | 36.13 | 16.14 | 46.17 | 20.87 | 179.39 | 83.18 | 262.57 | |
AS | 55.91 | 29.16 | 39.83 | 35.95 | 15.36 | 47.90 | 23.70 | 160.85 | 86.96 | 247.81 | |
EA | 86.19 | 18.41 | 30.51 | 26.41 | 14.95 | 49.47 | 22.44 | 161.52 | 86.86 | 248.38 | |
ES | 100.19 | 15.25 | 29.27 | 25.03 | 15.54 | 51.04 | 25.04 | 169.74 | 91.63 | 261.37 | |
FE | 43.51 | 11.13 | 28.07 | 22.37 | 14.73 | 49.18 | 23.44 | 105.08 | 87.35 | 192.44 | |
2 December | IN | 449.82 | 16.64 | 28.88 | 43.49 | 22.43 | 47.45 | 22.05 | 538.84 | 91.93 | 630.77 |
EG | 142.31 | 16.16 | 24.46 | 28.46 | 21.53 | 41.39 | 21.27 | 211.39 | 84.19 | 295.58 | |
AS | 103.53 | 14.86 | 24.19 | 27.51 | 22.37 | 44.11 | 18.42 | 170.09 | 84.90 | 254.99 | |
EA | 108.20 | 14.04 | 22.62 | 29.25 | 19.62 | 46.94 | 21.04 | 174.11 | 87.60 | 261.70 | |
ES | 84.94 | 13.97 | 20.88 | 25.70 | 29.07 | 42.15 | 18.21 | 145.50 | 89.44 | 234.93 | |
FE | 55.66 | 13.69 | 20.83 | 25.34 | 16.24 | 39.18 | 18.70 | 115.52 | 74.12 | 189.64 | |
9 December | IN | 480.58 | 27.31 | 41.74 | 59.41 | 36.59 | 51.87 | 25.75 | 609.04 | 114.21 | 723.24 |
EG | 217.03 | 18.90 | 31.12 | 37.77 | 24.83 | 43.08 | 18.33 | 304.81 | 86.24 | 391.05 | |
AS | 73.94 | 14.53 | 26.56 | 28.68 | 21.56 | 45.19 | 21.04 | 143.70 | 87.79 | 231.49 | |
EA | 58.82 | 13.36 | 22.95 | 27.69 | 21.83 | 45.34 | 20.14 | 122.81 | 87.32 | 210.13 | |
ES | 51.19 | 12.87 | 21.71 | 23.77 | 21.04 | 46.37 | 22.07 | 109.55 | 89.49 | 199.04 | |
FE | 107.75 | 17.02 | 25.19 | 28.54 | 24.24 | 42.54 | 17.46 | 178.49 | 84.23 | 262.73 | |
17 December | IN | 475.85 | 29.38 | 43.63 | 60.99 | 33.21 | 45.57 | 20.71 | 609.85 | 99.48 | 709.33 |
EG | 171.78 | 16.11 | 29.97 | 30.73 | 20.77 | 40.36 | 15.81 | 248.59 | 76.94 | 325.53 | |
AS | 51.55 | 13.77 | 24.80 | 26.77 | 18.63 | 40.18 | 15.95 | 116.90 | 74.76 | 191.66 | |
EA | 126.31 | 13.49 | 28.28 | 30.83 | 20.97 | 40.54 | 15.76 | 198.91 | 77.27 | 276.18 | |
ES | 92.23 | 13.40 | 25.07 | 27.36 | 20.14 | 40.02 | 15.64 | 158.07 | 75.81 | 233.88 | |
FE | 113.67 | 13.58 | 24.51 | 28.86 | 19.21 | 39.42 | 15.43 | 180.62 | 74.06 | 254.67 |
Ring | Compounds | Dewatered Sludge | Soil Standards | TEF a | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
23 November | 2 December | 9 December | 17 December | MHSPE b | RCLs c | CJ/T d | |||||||
2 | NAP | 76.10 | 51.22 | 45.87 | 41.53 | 15 | - | - | 0.001 | ||||
3 | ANE | 10.48 | 32.85 | 58.21 | 62.44 | - | - | - | 0.001 | ||||
ANA | 134.88 | 18.80 | 0.34 | 13.52 | - | - | - | 0.001 | |||||
FLU | 58.81 | 48.74 | 40.28 | 36.22 | - | - | - | 0.001 | |||||
PHE | 135.52 | 76.88 | 84.54 | 87.32 | 50 | - | - | 0.001 | |||||
ANT | 11.28 | 7.13 | 4.41 | 2.62 | 50 | - | - | 0.01 | |||||
4 | FLT | 59.58 | 57.47 | 49.07 | 45.61 | 15 | - | - | 0.001 | ||||
PYR | 18.55 | 7.88 | 13.21 | 11.28 | - | - | - | 0.001 | |||||
BaA e | 18.59 | 4.53 | 25.49 | 29.28 | 20 | 160 | - | 0.1 | |||||
CHR e | 93.61 | 58.39 | 64.74 | 68.13 | 20 | 16,000 | - | 0.01 | |||||
5 | BbF e | 47.77 | 29.64 | 21.72 | 17.91 | - | 160 | - | 0.1 | ||||
BkF e | 19.24 | 9.87 | 11.60 | 14.11 | 25 | 1600 | - | 0.1 | |||||
BaP e | 26.06 | 13.37 | 3.56 | 4.88 | 25 | 16 | 2000 | 1 | |||||
DBA e | 29.72 | 17.40 | 9.53 | 6.32 | 25 | 16 | - | 1 | |||||
6 | BghiP | 117.91 | 46.79 | 43.54 | 44.13 | - | - | - | 0.01 | ||||
IcdP e | 73.23 | 67.69 | 109.94 | 121.87 | 20 | 160 | - | 0.1 | |||||
∑PAHs-carc | 308.21 | 200.88 | 246.58 | 262.52 | - | - | - | - | |||||
∑LMW PAHs | 427.08 | 235.62 | 233.65 | 243.66 | - | - | - | - | |||||
∑HMW PAHs | 504.25 | 313.01 | 352.41 | 363.54 | - | - | - | - | |||||
∑PAHs | 931.33 | 548.64 | 586.06 | 607.20 | - | - | 5000 | - | |||||
∑PAHs-carc/∑PAHs | 33.1% | 36.6% | 42.1% | 43.2% | - | - | - | - |
Diagnostic Ratios | Main Source a | Dissolved Phase of Raw Sewage | Dewatered Sludge | ||||||
---|---|---|---|---|---|---|---|---|---|
23 November | 2 December | 9 December | 17 December | 23 November | 2 December | 9 December | 17 December | ||
ΣLMW/ΣHMW | <1 (Combustion) | 5.14 | 5.86 | 5.33 | 6.13 | 0.85 | 0.75 | 0.66 | 0.67 |
>1 (Petroleum) | |||||||||
ANT/(ANT + PHE) | <0.1 (Petroleum) | - | - | - | - | 0.08 | 0.08 | 0.05 | 0.03 |
>0.1 (Combustion) | |||||||||
FLT/(FLT + PYR) | <0.4 (Petroleum) | - | - | - | - | 0.76 | 0.88 | 0.79 | 0.80 |
0.4–0.5 (Petroleum combustion) | |||||||||
>0.5 (Biomass combustion) | |||||||||
BaA/(BaA + CHR) | <0.2 (Petroleum) | 0.68 | 0.68 | 0.67 | 0.69 | 0.17 | 0.07 | 0.28 | 0.30 |
>0.35 (Combustion) | |||||||||
IcdP/(IcdP + BghiP) | <0.2 (Petroleum) | - | - | - | - | 0.38 | 0.59 | 0.72 | 0.73 |
0.2–0.5 (Liquid fossil fuel combustion) | |||||||||
>0.5 (Biomass combustion) |
Q | RfD | Risk Index | ||||
---|---|---|---|---|---|---|
23 November | 2 December | 9 December | 17 December | |||
BaA | 0.73 | - | 1.6 × 10−5 | 1.3 × 10−5 | 1.4 × 10−5 | 1.3 × 10−5 |
CHR | 0.0073 | - | 7.7 × 10−8 | 6.1 × 10−8 | 5.7 × 10−8 | 5.1 × 10−8 |
NAP | - | 0.02 | 9.8 × 10−10 | 1.2 × 10−9 | 2.4 × 10−9 | 2.6 × 10−9 |
ANE | - | 0.06 | 8.3 × 10−11 | 1.0 × 10−10 | 1.3 × 10−10 | 1.0 × 10−10 |
ANA | - | 0.06 | 2.1 × 10−10 | 1.6 × 10−10 | 1.9 × 10−10 | 1.8 × 10−10 |
FLU | - | 0.04 | 2.5 × 10−10 | 2.8 × 10−10 | 3.2 × 10−10 | 3.2 × 10−10 |
PYR | - | 0.03 | 7.4 × 10−10 | 5.9 × 10−10 | 6.4 × 10−10 | 5.9 × 10−10 |
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Liu, Z.; Li, Q.; Wu, Q.; Kuo, D.T.F.; Chen, S.; Hu, X.; Deng, M.; Zhang, H.; Luo, M. Removal Efficiency and Risk Assessment of Polycyclic Aromatic Hydrocarbons in a Typical Municipal Wastewater Treatment Facility in Guangzhou, China. Int. J. Environ. Res. Public Health 2017, 14, 861. https://doi.org/10.3390/ijerph14080861
Liu Z, Li Q, Wu Q, Kuo DTF, Chen S, Hu X, Deng M, Zhang H, Luo M. Removal Efficiency and Risk Assessment of Polycyclic Aromatic Hydrocarbons in a Typical Municipal Wastewater Treatment Facility in Guangzhou, China. International Journal of Environmental Research and Public Health. 2017; 14(8):861. https://doi.org/10.3390/ijerph14080861
Chicago/Turabian StyleLiu, Zhineng, Qing Li, Qihang Wu, Dave T. F. Kuo, Shejun Chen, Xiaodong Hu, Mingjun Deng, Haozhi Zhang, and Min Luo. 2017. "Removal Efficiency and Risk Assessment of Polycyclic Aromatic Hydrocarbons in a Typical Municipal Wastewater Treatment Facility in Guangzhou, China" International Journal of Environmental Research and Public Health 14, no. 8: 861. https://doi.org/10.3390/ijerph14080861