Vermiremediation of allopathic pharmaceutical industry sludge amended with cattle dung employing Eisenia fetida

The present study aims to vermiremediate allopathic pharmaceutical industry sludge (AS) amended with cattle dung (CD), in different feed mixtures (AS:CD) i.e (AS0) 0:100 [Positive control], (AS25) 25:75, (AS50) 50:50, (AS75) 75:25 and (AS100) 100:0 [Negative Control] for 180 days using earthworm Eisenia fetida. The earthworms could thrive and grow well up to the AS75 feed mixture. In the final vermicompost, there were significant decreases in electrical conductivity (29.18-18.70%), total organic carbon (47.48-22.39%), total organic matter (47.47-22.36%), and C: N ratio (78.15-55.03%). While, significant increases in pH (12.94-17.80%), total Kjeldahl nitrogen (69.57-139.58%), total available phosphorus (30.30-81.56%), total potassium (8.82-22.22%), and total sodium (50.56-62.12%). The heavy metals like Cr (50-18.60%), Cd (100-75%), Pb (57.14-40%), and Ni (100-50%) were decreased, whereas Zn (8.37-53.77%), Fe (199.03-254.16%), and Cu (12.90-100%) increased significantly. The toxicity of the final vermicompost was shown to be lower in the Genotoxicity analysis, with values ranging between (76-42.33%). The germination index (GI) of Mung bean (Vigna radiata) showed a value ranging between 155.02 and 175.90%. Scanning electron microscopy (SEM) analysis showed irregularities with high porosity of texture in the final vermicompost than in initial mixtures. Fourier TransformInfrared Spectroscopy (FT-IR) spectra of final vermicompost had low peak intensities than the initial samples. The AS50 feed mixture was the most favorable for the growth and fecundity of Eisenia fetida, emphasizing the role of cattle dung in the vermicomposting process. Thus, it can be inferred that a cost-effective and eco-friendly method (vermicomposting) with the proper amendment of cattle dung and employing Eisenia fetida could transform allopathic sludge into a nutrient-rich, detoxified, stable, and mature vermicompost for agricultural purposes and further could serve as a stepping stone in the allopathic pharmaceutical industry sludge management strategies in the future.

Automated summary

This study aimed to investigate the vermicomposting of allopathic pharmaceutical industry sludge (AS) using cattle dung as a amendment. The results showed that the AS50 feed mixture was the most favorable for the growth and fecundity of Eisenia fetida. Vermicomposting significantly decreased the levels of electrical conductivity, total organic carbon, total organic matter, and C: N ratio, while increasing pH, total Kjeldahl nitrogen, total available phosphorus, total potassium, total sodium, and certain heavy metals. The toxicity of the final vermicompost was lower, as indicated by genotoxicity analysis. The germination index of Mung bean (Vigna radiata) was improved. Scanning electron microscopy and Fourier Transform Infrared Spectroscopy analysis revealed changes in the texture and composition of the final vermicompost compared to the initial mixtures. These findings highlight the potential of vermicomposting with cattle dung and Eisenia fetida in transforming allopathic sludge into a nutrient-rich and environmentally friendly vermicompost for agricultural use.