Diagnosis and ecotoxicological risk assessment of 49 elements in sludge from wastewater treatment plants of Chongqing and Xiamen cities, China

• Published in: Environmental science and pollution research international Vol. 25; no. 29; pp. 29006 - 29016
• Main Authors: Suanon, Fidèle, Chi, Qiaoqiao, Yang, Xiaoyong, Wang, Hongjie, Rashid, Azhar, Asefi, Bahareh, Mama, Daouda, Yu, Chang-Ping, Sun, Qian
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.10.2018; Springer Nature B.V
• Subjects: Anthropogenic factors; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Cadmium; China; Chromium; Cities; Contamination; Copper; Earth and Environmental Science; Ecotoxicology; Ecotoxicology - methods; Environment; Environmental Chemistry; Environmental Health; Environmental risk; Environmental science; Lead; Manganese; Metals; Metals - analysis; Metals - toxicity; Metals, Heavy - analysis; Metals, Heavy - toxicity; Nickel; Pollution; Pollution index; Pollution load; Principal Component Analysis; Principal components analysis; Research Article; Risk assessment; Risk Assessment - methods; Sewage - analysis; Sewage - chemistry; Sludge; Spatial variations; Waste Disposal, Fluid - methods; Waste Water Technology; Wastewater treatment; Wastewater treatment plants; Water Management; Water Pollutants, Chemical - analysis; Water Pollutants, Chemical - toxicity; Water Pollution Control; Water treatment; Water treatment plants; Zinc; China; Cities; Sludge; Elements; Ecotoxicological risk; Pollution indices
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-018-2888-z

Limited information about the sludge quality is a major constraint for its usage and proper disposal. This study investigated the occurrence of 49 elements in sludge from 11 wastewater treatment plants (WWTPs) in Chongqing and Xiamen cities of China. The concentration of 46-detected elements ranged from 16.2 μg kg −1 (Pt) to 55.0 g kg −1 (Al) on dry solid basis in the sludge. The enrichment factor of most of the elements was > 1.5, indicating their possible anthropogenic origin. The precious metals had considerably higher enrichment factor ranging from 56.3 to 200,000. Principal component analysis clustered the samples from Chongqing and Xiamen separately to suggest strong spatial variations. Contamination factor, pollution loading index, and integrated pollution degree were calculated to evaluate the elemental pollution risk. The pollution loading index indicated unpolluted to highly polluted levels of the elements in the sludge. In addition, results from the ecotoxicological risk index showed an individual low to very high ecotoxicological risk posed by eight metal(loid)s (As, Cd, Cr, Cu, Mn, Ni, Pb, and Zn) in the WWTPs.