The ecological and human health risks associated with six heavy metals (Cd, Cu, Pb, Zn, Ni, Hg) in phosphate effluent from a wastewater treatment plant in Gafsa-Metlaoui, Tunisia, were comprehensively assessed. Multivariate analysis revealed strong correlations among Zn, Cu, and Cd indicating a common anthropogenic source related to mining activities. Multiple contamination indices, including contamination factor (CF), ecological risk (Er), geoaccumulation index (Igeo), and toxic risk index (TRI), consistently indicated moderate to high levels of contamination, with cadmium identified as the dominant contributor to ecological risk. Human health risk assessment showed that non-carcinogenic risks (HI < 1) remained within acceptable limits for both adults and children. However, carcinogenic risk values exceeded the permissible threshold (10 −4 ) for Cd, Cu, Pb, and Ni, with children exhibiting higher vulnerability. Plant analysis using atomic absorption spectrophotometry demonstrated significant accumulation of heavy metals in fenugreek, lentil, wheat, and radish irrigated with phosphate wastewater. Cadmium, lead, and iron showed enhanced translocation to aerial parts, whereas copper was primarily retained in roots. Notably, wheat exhibited a strong capacity for lead translocation, highlighting potential risks for food chain contamination. Overall, the findings reveal significant ecological and human health concerns associated with phosphate wastewater reuse. The integration of pollution indices, health risk assessment, and plant uptake analysis provides a comprehensive evaluation framework. Additionally, the observed accumulation patterns suggest that certain plant species may have potential for phytoremediation applications. These results offer valuable insights for environmental management and sustainable agricultural practices in phosphate-affected regions, while the integration of multiple assessment approaches provides a comprehensive framework for understanding heavy metal transfer and associated risks.
Sai et al. (Sat,) studied this question.