Asian Journal of Advanced Research and Reports

The health risk associated with poisoning due to heavy metal pollution ranges from the consumption of plants with bio-accumulated metals, and animals has increased the need for environmental clean-up from heavy metal pollution. This study aimed to assess the bioremediation potential of waste and heavy metals from polluted soil using black soldier fly in synergy with soil flora. Garbage soil site containing restaurant and fruit waste was collected and evaluated for the microbial flora using conventional techniques. The total viable counts from the mixture were enumerated. Larva of black soldier flies was added to make the total 100g. The heavy metals from the mixture and the bioaccumulation factors were evaluated. The rate of waste decomposition was also monitored. Following the characterisation procedures, the slurry waste sample revealed the presence of isolates homologous to Pseudomonas species, Bacillus species, Staphylococcus aureus, and Streptococcus species. High microbial counts, both on general-purpose media and selective agar, were recorded, ranging from 1.2 x 10⁶ to 3.5 x 10⁶ cfu/ml on Nutrient agar within 24 hours and a reduction after 48 hours, ranging from 5.0 x 10⁵ to 1.3 x 10⁶. The total viable count on MacConkey agar reduces from 3.5 x 10⁶ cfu/ml to 1.3 x 10⁶ after 24 hours of incubation with BSFL, a possible indication of an amino-peptide with antimicrobial effect against Gram-negative bacteria. A reduction in heavy metal concentration from the restaurant /garbage site consortium with larvae of black soldier flies was also recorded, with zinc drastically reducing from 24.67 mg/kg to 8.53 mg/kg, followed by cadmium (9.15 mg/kg to not detect) and a reduction of lead from 11.07 to not detect. The bioaccumulation factor of heavy metal composition of black soldier fly larva (BSFL) revealed that Zinc (Zn) showed the highest value on the fifteenth day of incubation, with a value of 18.03mg/kg, with lead (Pb) following a similar trend (7.78 mg/kg). A drastic reduction in the volume of the test waste sample from 100g to 29.25g showed the degradation potential of BSFL on waste management that is yet untapped. The results obtained from the heavy metal removal by BSFL from waste showed its potency in the detoxification of the environment the heavy metal poisoning.