However, the repeated failure of the microbiological test
replicates of most samples indicated that these brands
might have suffered from inherent problems such as
handling, source of raw materials, poor sanitary
properties from the environment during manufacturing
processes as reported earlier on.
14,21
The reoccurring
contamination in different batches of the same brand
brings doubts about the effectiveness and compatibility of
the preservative system with other ingredients used in
formulations. Whereby the appropriate preservatives had
been used, the products would have inhibited
contaminants. Similarly product pH and noncompatibility of raw material such as fragrances can be
about coloration in some creams. Reports have shown
that chemicals such as lipids, polysaccharide, proteins,
alcohol and glucoside of cosmetics can support growth of
microorganisms in the cosmetics products.
12,18
The other
factors that affect stability of cosmetics products are
temperature of storage, availability of O2
and poor
activity of preservative as mentioned earlier. It has been
reported that the presence of Bacillus sp. might be
responsible for unpleasant odor and spoilage of cosmetic
products