Assessing the Environmental Safety of Sewage Sludge: C. elegans as a Model for Toxicity Evaluation
DOI:
https://doi.org/10.65761/jbs.v2.i1.9Keywords:
Sewage sludge, Ecotoxicity, Caenorhabditis elegans, Heavy metals, Wastewater treatmentAbstract
Background: Sewage sludge, a by-product of wastewater treatment plants (WWTPs), is frequently applied as an agricultural amendment due to its nutrient-rich composition. However, the presence of heavy metals, pesticides, and polycyclic aromatic hydrocarbons (PAHs) raises concerns regarding ecological safety.
Objective: This study aimed to assess the environmental safety of wet and sun-dried sludge from the Bharwara WWTP, Lucknow, using Caenorhabditis elegans as a model organism.
Methods: Chemical analysis of wet and dry sludge samples included heavy metals, pesticide residues and PAHs. Ecotoxicological analysis was the determination of growth, recovery, and reproductive productivity of C. elegans in sludge.
Results: Sludge that was wet had a higher number of contaminants than dry, and this means that sun-drying is effective in decreasing the number of toxicants. C. elegans growth was not largely affected but wet sludge greatly affected recovery and reproduction but dry sludge was not so toxic.
Implication: Sludge processing has a great impact on ecological safety. Sludge dried in the sun is less harmful to soil organisms and C. elegans is a sensitive model to use in integrated toxicity evaluations. The results indicate the significance of post-treatment measures to achieve sustainable and safe repurposing of sewage sludge to agriculture.
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