Human Exposure Pathways of Heavy Metals in a Lead-Zinc Mining Area, Jiangsu Province, China

Abstract

Heavy metal pollution is becoming a serious issue in developing countries such as China, and the public is increasingly aware of its adverse health impacts in recent years. We assessed the potential health risks in a lead-zinc mining area and attempted to identify the key exposure pathways. We evaluated the spatial distributions of personal exposure using indigenous exposure factors and field monitoring results of water, soil, food, and indoor and outdoor air samples. The risks posed by 10 metals and the contribution of inhalation, ingestion and dermal contact pathways to these risks were estimated. Human hair samples were also analyzed to indicate the exposure level in the human body. Our results show that heavy metal pollution may pose high potential health risks to local residents, especially in the village closest to the mine (V1), mainly due to Pb, Cd and Hg. Correspondingly, the residents in V1 had higher Pb (8.14 mg/kg) levels in hair than those in the other two villages. Most of the estimated risks came from soil, the intake of self-produced vegetables and indoor air inhalation. This study highlights the importance of site-specific multipathway health risk assessments in studying heavy-metal exposures in China.

Multiple Exposure and Effects Assessment of Heavy Metals in the Population near Mining Area in South China

“…Some subjects in FD showed even higher levels of Cd and Pb, with the maxima estimated at 1.94 and 38 mg/kg, respectively. The average levels of hair Pb, Cd, Cu and Zn in the study area were lower than the levels in the scalp hair of adults from S. Domingos mine, Portugal [60], but higher than those recorded in a lead-zinc mining area from China [9]. Interestingly, the Zn concentration in hair of a non-exposed population was higher than that of subjects living near the Dabaoshan mine, which might be due to the higher concentration of toxic metals like Cd and Pb in the vicinity, which can interact with Zn and replace it in the heme enzymes and metallothioneins [61].…”

How Do the Chinese Perceive Ecological Risk in Freshwater Lakes?

“…For example, Cabrera et al [53] found that the sensitivity to health risk of pesticide will affect the farm workers’ behavior. In many exposure assessment studies [54], [55], researchers have found that individuals’ behaviors would result in the difference of actual risk. Huang et al [56] and Marchwinska et al [57] believed improving access to education and better risk communication to increase sensitivity will reduce high-risk behaviors and strengthen local governments’ credibility for risk reduction, control and management.…”

Evaluation of human risks of surface water and groundwater contaminated with Cd and Pb in the southern El-Minya Governorate, Egypt

“…The stratigraphic succession (Fig. 2) in the El-Minya area is represented by Tertiary and Quaternary sedimentary rocks (Said, 1981). The main aquifer in the study area is represented by Pleistocene sediments which are composed of sand and gravel of different sizes with some clay intercalation (Sadek, 2001).…”

“…So, quantifying human risk (carcinogenic and non-carcinogenic risks) of Cd and Pb to children and adults is important. The hazard quotient (HQ) is extensively used to characterize the carcinogenic and non-carcinogenic health effects of toxic metals by comparison of their exposure effects to a reference dose (Rf D) (Qu et al, 2012). This was documented in several studies by taking into consideration exposure scenarios of metal intake through contaminated water (Muhammad et Shah et al, 2012;Dou and Li, 2012).…”