Bioaccumulation of trace metals in edible terrestrial snails, Theba pisana and Otala spp., in a dumpsite area in Morocco and assessment of human health risks for consumers.

This study assessed the bioaccumulation patterns of five trace metals (Cd, Cr, Co, Cu, and Zn) in two edible snail species, Theba pisana and Otala spp., collected from a dumpsite in Safi City, Morocco. The results indicated that bioaccumulation might be species-specific, as metal concentration profiles varied between the two snail species. Additionally, higher metal levels in the dumpsite snails confirmed their potential as bioindicators of trace metal pollution in terrestrial environments. However, the distribution of trace elements within the edible parts of the snails showed marked unevenness, with the viscera accumulating more metals than the foot. The study also evaluated the potential human health risks associated with consuming these snails. Trace metal levels in the edible parts exceeded most international safety thresholds. The estimated daily intakes (EDIs) of trace metals through snail consumption were below the provisional tolerable daily intakes (PTDIs) for both children and adults, suggesting that daily consumption is generally safe. Nonetheless, the hazard index (HI) indicated that children might face health risks from long-term consumption of contaminated snails (HI > 1), while adults are less likely to experience such complications (HI < 1). The total target carcinogenic risk (TTCR) was below 1E-04 for both children and adults, indicating negligible to acceptable carcinogenic risks for all consumer groups.

Soil contamination by trace metals and assessment of the risks associated: the dumping site of Safi city (Northwest Morocco).

The main objective of this work was to determine the soil contamination with trace metals within and around the dumpsite of Safi city (Morocco) and to evaluate the potential environmental risk associated. The results showed that the average soil concentrations of trace metals had the following order: Fe > Zn > Cu > Cr > Cd and exceeded the world and the upper continental background concentrations except for Fe. In addition, the concentrations of Zn, Cu, and Cd remained beyond the limit standards given by the WHO/FAO. Geoaccumulation index, enrichment factor, and pollution load index (PLI) indicated that the dumpsite soil is highly contaminated and deteriorated, presenting evidence of high ecological risk proved by the values of the potential ecological risk index (PERI). Correlation analyses revealed a strong relationship between the organic matter & [Fe, Zn, Cr, Cd], calcium carbonates & [Zn, Cr], and Cr & Cu inside the dumpsite soil. Principal component analysis confirmed the temporal and spatial classification of Zone A as the oldest and Zone C as the youngest and indicated that the regrouped trace metals could have the same behavior and or the same origin. The interpolation of trace metals concentrations and PERI revealed a plausible extension outside the landfill, confirmed by PLI values.