CHARACTERISATION OF BACTERIAL STRAINS FOR THEIR HEAVY-METAL BIOREMEDIATION POTENTIAL IN A SELECTED COSMETIC PRODUCT

ABSTRACT The presence of heavy metals in cosmetics has become a developing public health concern because of their toxic and potentially carcinogenic effects. This study is aimed at evaluating selected cosmetic products for heavy metal contamination and to analyze the potential of probiotic and non-probiotic bacteria for bioremediation. Sixteen cosmetic samples, including lotions and hair relaxers, were bought from the market and analyzed for heavy metals—Cadmium, Nickel, Chromium and Lead using Atomic Absorption Spectrophotometry (AAS). To explore a biotechnological solution, bacteria were isolated from fermented African oil bean seeds (ugba) and fresh tomatoes.These isolates were subjected to experiments to test their ability to reduce heavy metal concentrations in heavy metal contaminated products. Isolated bacteria were identified via molecular techniques. Experimental results showed that while most metals were within acceptable limits, Lead was present above permissible limits in some samples, raising significant concerns about safety. A total of thirteen isolates were obtained and tested for their tolerance to heavy metals. Out of these three isolates (T2, U2 and U3) showed strong tolerance, particularly to Zinc and Lead. Results revealed that the bacteria, especially isolate U3, significantly reduced Lead concentrations through bioaccumulation mechanism. Further molecular analysis identified U2 and U3 as Providencia burhodogranariae and Corynebacteruim stationis, repectively. While Lead was effectively reduced, there was no visible change in Cadmium levels. These results demonstrate the promising potential of certain probiotic and non-probiotic bacteria in the bioremediation of heavy metal contaminated cosmetic products. In conclusion, this study not only highlights the presence of heavy metals in everyday cosmetic products but also suggests the use of probiotic microorganisms as a natural, cost-effective approach to mitigate these contaminants. Further research is recommended to expand the scope of probiotic and non-probiotic strains and optimize their application in cosmetic safety management.