Evaluation of quality of some commonly used herbal medicinal plants in local markets of FCT, Abuja, Nigeria

The safety of herbal medicines has become a major concern to both national health authorities and the general public. Hence their production, quality, distribution and use are regulated. Some medicinal plants commonly used for malaria, diabetes and Tuberculosis and respiratory conditions were evaluated for qual-ity. The objective of the study is to assess some quality specifications, physicochemical and heavy metals of some medicinal plant extracts. The samples were identified, purchased, processed and analyzed using appropriate standards methods specified by WHO and AOAC; while the heavy metals content was analyzed using Atomic Absorption Spectrophometer (AAS). All the analyzed samples passed WHO permissible limit established for heavy metals content, however 42.8 and 21.4% of the samples failed moisture and ash con-tent permissible limits respectively. High level of moisture content will favor microbial and fungal growth and shortens shelf-life of the samples. The WHO maximum permissible limits for moisture and ash content are ≤15 and ≤8. The ash content was also above standard permissible limit in 80% of the samples, this could be associated to improper handling that has resulted to introduction of inorganic substances such as silica and other inorganic matters. The levels of heavy metals content were all below the WHO maximum per-missible limits. The moisture, ash and heavy metals are among the important parameters of medicinal plants that require frequent routine monitoring in order to ensure safety.