Health risks from the exposure of children to As, Se, Pb and other heavy metals near the largest coking plant in China

Abstract

• The concentration of heavy metals and metalloids in environment and children's blood are observed around the Chinese largest coking plant.• The health risk assessments of children are analyzed.• Foods from the coking plant are heavily contaminated by As, Cr and Se.• Food Ingestion pathway contributes most to children's average daily dose for most heavy metals and metalloids.• Higher potentially non-carcinogenic and carcinogenic risks happen to the local children. a b s t r a c t a r t i c l e i n f o Coking influences environmental quality and poses high risks to human health as large amounts of heavy metals and metalloids are emitted into the environment from coal during the coking process. Health risks depend heavily on multi-pathway and element-specific exposures, which have, unfortunately, been rarely studied. In this study, children's health risks and exposure levels to As, Se, and heavy metals (Pb, Cd, Cr, Ni, Co, Zn, Cu, Mn, V and Sb) in the water, soil, dust, air and locally produced food were studied based on field sampling and questionnaire-based surveys around the largest coking area in China. Human blood samples were collected and analyzed to indicate the exposure levels. The non-carcinogenic risks to children mainly resulted from Cr, Mn, Pb, As and Sb, the levels of which were 3 to 10 times higher than the acceptable levels (1.0 × 10 −6 ). The carcinogenic risks to children were 30 to 200 times higher than the safe level (1.0 × 10 −6 -1.0 × 10 −4 ), which could be attributed to Cr, As and Ni pollution. The estimated risks mainly came from the pathway involving the ingestion of locally produced food, accounting for more than 85% in total for most elements. For As, the food ingestion and air inhalation exposure pathways both contributed approximately 50%, respectively. The high risks in this study highlight the attention paid to the health of children who live in the vicinity of coking activities and the importance of site-specific multi-pathway health risk assessments and food safety to protect potentially exposed children.

Health risk assessment of various metal(loid)s via multiple exposure pathways on children living near a typical lead-acid battery plant, China

“…The contents of heavy metal(loid)s in children's blood are shown in Table 2. In agreement with previous studies (Cao et al, 2014;Wu et al, 2011b), a negative correlation was found between Pb and Zn, after controlling for gender and age. This could be attributed to the fact that Zn plays an important role in Pb metabolism (Jamieson et al, 2006).…”

“…The results illustrated that the ADD of children was largely attributed to food ingestion for most heavy metal(loid)s, especially for Co, Cu, Zn, Se and Cd, which accounted for 95.97, 99.13, 98.88, 95.85 and 95.32%, respectively. The result was in accordance with the previous study conducted near a coking area, which indicated that food ingestion was the largest contributor to the total ADD of metal(loid)s exposure (Cao et al, 2014). However, for As, dust ingestion was another large contributor to the ADD, which accounted for 21.90%.…”

“…Actually, the HQs for most heavy metal(loid)s via PM 10 inhalation were 1.0 Â 10 2 to 1.0 Â 10 5 times higher than those of soil and dust routes via inhalation exposure. In particular, the HQs for Cr and Mn via PM 10 inhalation were 4.75 and 8.48 at the 5th percentile, respectively, indicating that the higher Cr and Mn contents in PM 10 would pose a risk of harmful effect to the local children, which had also been found in a previous study (Cao et al, 2014). In this study, the mean combined HIt for all heavy metal(loid)s were 45.4, indicating a higher potential non-carcinogenic risk to the local children when compared to the previous results (Cao et al, 2014;Qu et al, 2012).…”

“…In addition, the studied children with a height of 102e121 cm mostly living in the bungalow, were likely to inhale the heaviest lead-contaminated zone in the air, which is 75e100 cm above the ground (Dong et al, 2001;Wang and Zhang, 2006). Moreover, the children's BLLs in this study, were much higher than those of children living around a coking plant (Cao et al, 2014), an traffic area ) and a smelting facility (Soto-Jimenez and Flegal, 2011). The variance can be explained by the aforementioned factors related to the children, and the heavier contamination status in our site, as environmental lead pollution was reported to be a factor in the children's elevated BLLs (Wang and Zhang, 2006).…”

“…2 and 18 samples of 24-h indoor PM 10 from the school and volunteers' homes were respectively collected on pre-combusted (500 C, 6 h) quartz microfiber filters (Munktell In C., Sweden) using an established sampling method (Cao et al, 2014). Another 2 samples outside the school were also sampled.…”