Spatial distribution and risk assessment of toxic metals in agricultural soils from endemic nasopharyngeal carcinoma region in South China

Abstract

Sihui city (South China) is much affected by nasopharyngeal carcinoma (NPC). To investigate the relationships between the toxic metals in soil and NPC incidence in Sihui, 119 surface soil samples were collected from agricultural fields and analyzed. The soil As–Cr contents in Longjiang (high-incidence area) are significantly lower than those in Weizheng and Jianglin (low-incidence areas), whereas the soil Pb content in Longjiang is significantly higher than that in Weizheng. The Nemerow pollution indices (PIN) of soils decrease in the order of Jianglin > Weizheng > Longjiang. The enrichment factor (EF) of Cd indicates that the Cd enrichment is contributed by human activities. Potential toxic metal-related ecological risk values decrease in the order of Jianglin > Weizheng > Longjiang. The mean hazard index (HI) value of Longjiang was lower than those of Weizheng and Jianglin. There are no adverse noncarcinogenic health effects of soil toxic metals to adults in the study areas. Carcinogenic risks of As and Cr via ingestion and dermal contact and total carcinogenic risk are within the warning range, from 10−6 to 10−4. Hence, we suggest that toxic metals in the soil may not be major geochemical carcinogenic factors of high NPC incidence in Sihui.

Pollution and health risk assessment of trace metal in vegetable field soils in the Eastern Nile Delta, Egypt

“…Therefore, children have much more chances of carcinogenic risk from Cr exposure in the study area than adults. Similar results were found by Song et al ( 2018 ), Mo et al ( 2020 ), and Liu et al ( 2021 ) who reported that Cr posed a significant carcinogenic risk. Moreover, previous studies have revealed that human exposure to low Cr concentrations for the long term can cause poisonous and cancer-causing impacts in people (Khan et al, 2015 ).…”

“…In the same line, higher contents of Cd, Pb, Cu, and Zn were observed in vegetable fields in China (Kuerban et al, 2020 ). The main contribution of trace metals to agricultural soil is the use of chemical fertilizers, pesticides, and organic fertilizers (Kuerban et al, 2020 ; Mo et al, 2020 ; Omran, 2016 ). Thus, Cd, Co, Pb, and Zn will require more attention in the future, and continuous monitoring of the application of agrochemicals in the production of vegetables is recommended to decrease the probable ecological risks caused by these trace metals in the soil of the Eastern Nile Delta.…”

“…The soil properties, especially soil organic matter and clay particle content, effectively absorb trace metals (Khalifa & Gad, 2018 ). Soil organic matter is one of the main soil properties with dual effects on trace metals mobility (Mo et al, 2020 ). This may be because organic matter decomposition produces organic chemicals into soil solution that might act as chelates and raise the bioavailability of trace metals.…”

“…Moreover, it can threaten food security by adverse effects on crop quality and the health of animals. These might cause potential risks to human health through the food supply chain and groundwater consumption (Mo et al, 2020 ; Salman et al, 2019 ). The trace metals of agricultural soil can mainly enter the human body through three exposure routes: ingestion, inhalation, and skin contact (Castro-González et al, 2017 ).…”