Pollution level and risk assessment of heavy metals in sewage sludge from eight wastewater treatment plants in Wuhu City, China

  • Hanwen Zhang School of Public Health, Wannan Medical College, Wuhu, Anhui
  • Yuee Huang School of Public Health, Wannan Medical College, Wuhu, Anhui
  • Shu Zhou School of Public Health, Wannan Medical College, Wuhu, Anhui
  • Liangchen Wei School of Public Health, Wannan Medical College, Wuhu, Anhui
  • Zhiyuan Guo School of Public Health, Wannan Medical College, Wuhu, Anhui
  • Jinchun Li School of Public Health, Wannan Medical College, Wuhu, Anhui
Keywords: contamination evaluation, source identification


Aim of study: To investigate the content, contamination levels and potential sources of five heavy metals (Hg, Pb, Cd, Cr, As) in sewage sludge from eight wastewater treatment plants (W1 to W8).

Area of study: Wuhu, located in southeastern Anhui Province, southeastern China.

Material and methods: The sewage sludge pollution assessment employed the single-factor pollution index, Nemerow’s synthetic pollution index, monomial potential ecological risk coefficient and potential ecological risk index. The potential sources among the five heavy metals were determined using the Pearson’s correlation analysis and principal component analysis (PCA).

Main results: The mean concentrations of the heavy metals were 0.27 mg/kg (Hg), 70.78 mg/kg (Pb), 3.48 mg/kg (Cd), 143.65 mg/kg (Cr) and 22.17 mg/kg (As). W1, W5 and W6 sewage sludge samples showed the highest levels of heavy metal contamination, and cadmium had the highest contamination level in the study area. Pearson’s correlation analysis and PCA revealed that Pb and Cd mainly derived from traffic emissions and the manufacturing industry and that As and Cr originated from agricultural discharges.

Research highlights: The pollution of cadmium in Wuhu should be controlled preferentially. The heavy metal pollution of W1, W5 and W6 sewage treatment plants is relatively high, they should be key prevention targets.


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How to Cite
ZhangH., HuangY., ZhouS., WeiL., GuoZ., & LiJ. (2020). Pollution level and risk assessment of heavy metals in sewage sludge from eight wastewater treatment plants in Wuhu City, China. Spanish Journal of Agricultural Research, 18(2), e1103. https://doi.org/10.5424/sjar/2020182-15796
Soil science