Source identification of heavy metals and metalloids in soil using open-source Tellus database and their impact on ecology and human health

• Published in: The Science of the total environment 2024-11, Vol.953, p.175987, Article 175987
• Main Authors: Uddin, Rayhan, Hopke, Philip K., Van Impe, Jan, Sannigrahi, Srikanta, Salauddin, Md, Cummins, Enda, Nag, Rajat
• Format: Article
• Language: English
• Subjects: Exposure assessment; Food safety; Pollution; Positive Matrix Factorization (PMF); Risk assessment; Topsoil
• ISSN: 0048-9697; 1879-1026; 1879-1026
• DOI: 10.1016/j.scitotenv.2024.175987

The presence of heavy metals and metalloids (metal(loid)s) in the food chain is a global problem, and thus, metal(loid)s are considered to be Potentially Toxic Elements (PTEs). Arsenic (As), lead (Pb), mercury (Hg), and cadmium (Cd) are identified as prominent hazards related to human health risks throughout the food chain. This study aimed to carry out a source attribution for metal(loid)s in shallow topsoil of north-midlands, northwest, and border counties of the Republic of Ireland, followed by an assessment of the potential ecological and human health risks. The positive Matrix Factorization (PMF) was used for source characterization of PTEs, followed by the Monte Carlo simulation method, used for a probabilistic model to evaluate potential human health risks. The mean concentrations of prioritized metal(loid)s in the topsoil range in the order of Pb (28.83 mg kg−1) > As (7.81 mg kg−1) > Cd (0.51 mg kg−1) > Hg (0.11 mg kg−1) based on the open-source Tellus dataset. This research identified three primary sources of metal(loid) pollution: geogenic sources (36 %), mixed sources of historical mining and natural origin (33 %), and anthropogenic activities (31 %). The ecological risk assessment showed that Ireland's soil exhibits low-moderate pollution levels however, concerns remain for Cd and As levels. All metal(loid)s except Cd showed acceptable non-carcinogenic risk, while Cd and As accounted for high to moderate potential cancer risks. Potato consumption (if grown on land with elevated metal(loid) levels), Cd concentration in soil, and bioaccumulation factor of Cd in potatoes were the three most sensitive parameters. In conclusion, metal(loid)s in Ireland present low to moderate ecological and human health risks. It underscores the need for policies and remedial strategies to monitor metal(loid) levels in agricultural soil regularly and the production of crops with low bioaccumulation in regions with elevated metal(loid) levels. [Display omitted] •Positive Matrix Factorization (PMF) characterized sources of heavy metal(loid)s.•Sources: anthropogenic, geogenic, & mixed sources of prior mining and natural origin•Simulated mean levels: Pb (28.83) > As (7.81) > Cd (0.51) > Hg (0.11) (mg kg−1)•Ecological risk was found to be low to moderate; Cd poses the highest risk.•Potato consumption and Cd levels are sensitive factors in health risk.