Probabilistic Human Health Risk Assessment of Heavy Metal Intake via Vegetable Consumption around Pb/Zn Smelters in Southwest China

Abstract

Vegetable contamination in mining and smelting areas has resulted in high dietary intakes of heavy metals, which pose potential health risks to local residents. In this study, paired soil-vegetable samples were collected around Pb/Zn smelters in Southwest China. Probabilistic risks to local residents via vegetable consumption were evaluated with a Monte Carlo simulation. The mean concentrations of As, Cd, Cu, Pb, and Zn in the soils were 116.76, 3.59, 158.56, 196.96, and 236.74 mg/kg, respectively. About 38.18%, 58.49%, and 52.83% of the vegetable samples exceeded the maximum allowable concentrations for As, Cd, and Pb, respectively. The daily dietary intake of As, Cd, and Pb exceeded the provisional tolerable daily intakes for local residents, with children showing the highest intake via vegetable consumption. The percentages of the target hazard quotients of As, Cd, and Pb for local residents exceeding the safe value of one were about 95%, 50%, and 25%, respectively. The 95th percentiles of the hazard index for children, adolescents, and adults were 15.71, 11.15, and 9.34, respectively, indicating significant risks to local residents, especially children. These results highlight a need to develop effective strategies to reduce heavy metal contamination and exposure to protect human health.

Hazardous Heavy Metals Accumulation and Health Risk Assessment of Different Vegetable Species in Contaminated Soils from a Typical Mining City, Central China

“…In this study, As had a higher THQ value than other hazardous heavy metals. A similar report also confirmed that As exposure through vegetable ingestion has significant adverse effects on residents [ 23 ]. Thus, much attention should be paid to As although there is a lack of detailed criteria of chemical form.…”

“…Previous studies have reported that elevated concentration of HMs was found near the multiple-metal mining and smelter, e-waste dismantling area, and industrial sites [ 16 , 23 , 45 , 53 ]. In addition, Rahmdel et al [ 17 ] and Mandal et al [ 20 ] reported that higher concentrations of Cu and Pb in leaf vegetables were observed in Iran and India than those in the present study, in which samples were collected near the rural districts of industrial town.…”

“…In addition, Rahmdel et al [ 17 ] and Mandal et al [ 20 ] reported that higher concentrations of Cu and Pb in leaf vegetables were observed in Iran and India than those in the present study, in which samples were collected near the rural districts of industrial town. Comparatively, in China, the average concentrations of HMs in vegetables were mostly similar to those in the peri-urban areas, but most of them were significantly higher than those from Pb/Zn smelters in Gejiu of Yunnan province [ 23 ], and seven areas in Zhuzhou of Hunan Province [ 22 ]. Therefore, we inferred that this was possibly linked to the industrial activities of local copper mining and smelter operations in Daye City.…”

“…It is noteworthy that, currently, the Chinese government is paying considerable attention to food security, especially the concentration of HMs in vegetables and crops [ 12 , 20 ]. Many studies have investigated the heavy metal pollution of vegetables near tungsten mining in Gannan of Jiangxi [ 21 ]; Zhuzhou smelter of Hunan [ 22 ]; Jijie Pb/Zn smelter of Yunnan [ 23 ]; Tonglushan copper ming of Hubei in China [ 3 ], and other countries [ 24 , 25 , 26 , 27 ]. These findings revealed that most of the vegetables in the exposed areas exceed the maximum permissible concentration, and even caused a higher health risk than those in non-contaminated areas.…”

Application of Geostatistical Analysis and Random Forest for Source Analysis and Human Health Risk Assessment of Potentially Toxic Elements (PTEs) in Arable Land Soil

“…The non-carcinogenic risk of human PTEs is expressed by the hazard quotient ( ), which is the ratio of the daily human exposure dose ( , mg·kg −1 ·d −1 ) to the reference dose ( , mg·kg −1 ·d −1 ) [ 25 ]. The specific calculation formula is as follows …”