Heavy metal accumulation in soils, plants, and hair samples: an assessment of heavy metal exposure risks from the consumption of vegetables grown on soils previously irrigated with wastewater.
It is common knowledge that soils irrigated with wastewater accumulate heavy metals more than those irrigated with cleaner water sources. However, little is known on metal concentrations in soils and cultivars after the cessation of wastewater use. This study assessed the accumulation and health risk of heavy metals 3 years post-wastewater irrigation in soils, vegetables, and farmers' hair. Soils, vegetables, and hair samples were collected from villages previously irrigating with wastewater (experimental villages) and villages with no history of wastewater irrigation (control villages). Soil samples were digested in a mixture of HCL/HNO3/HCLO4/HF. Plants and hair samples were digested in HNO3/HCLO4 mixture. Inductive coupled plasma-optical emission spectrometer (ICP-OES) was used to determine metal concentrations of digested extracts. Study results indicate a persistence of heavy metal concentration in soils and plants from farms previously irrigated with wastewater. In addition, soils previously irrigated with wastewater were severely contaminated with cadmium. Hair metal concentrations of farmers previously irrigating with wastewater were significantly higher (P < 0.05) than farmers irrigating with clean water, but metal concentrations in hair samples of farmers previously irrigating with wastewater were not associated with current soil metal concentrations. The study concludes that there is a persistence of heavy metals in soils and plants previously irrigated with wastewater, but high metal concentrations in hair samples of farmers cannot be associated with current soil metal concentrations.
School of Public Health, Hebei Medical University, 361 Zhongshan Road, Shijiazhuang, Hebei, China.
Lamin Daddy
LD
Massaquoi
Shijiazhuang Center for Disease Control and Prevention, Shijiazhuang, China.
Hui
H
Ma
School of Public Health, Hebei Medical University, 361 Zhongshan Road, Shijiazhuang, Hebei, China.
Xue Hui
XH
Liu
School of Public Health, Hebei Medical University, 361 Zhongshan Road, Shijiazhuang, Hebei, China.
Peng Yu
PY
Han
Shijiazhuang Center for Disease Control and Prevention, Shijiazhuang, China.
Shu-Mei
SM
Zuo
Shijiazhuang Center for Disease Control and Prevention, Shijiazhuang, China.
Zhong-Xian
ZX
Hua
School of Public Health, Hebei Medical University, 361 Zhongshan Road, Shijiazhuang, Hebei, China. liudw56@tom.com.
Dian-Wu
DW
Liu
D005260:Female; D005506:Food Contamination; D006197:Hair / Q000737:chemistry*; D006801:Humans; D008297:Male; D019216:Metals, Heavy / Q000032:analysis*; D018570:Risk Assessment; D012989:Soil Pollutants / Q000032:analysis*; D014675:Vegetables / Q000737:chemistry*; D062065:Wastewater; D014873:Water Pollutants
D019216:Metals, Heavy; D012989:Soil Pollutants; D062065:Wastewater; D014873:Water Pollutants
Agriculture; Bio-concentration; Daily metal intake; Geo-accumulation; Health hazard; Heavy metals; Risk assessment; Wastewater