HEAVY METAL CONTAMINATION OF PHARMACEUTICAL PRODUCTS COMMONLY SOLD IN NIGERIA

Abstract

The study evaluates the contamination by heavy metals of pharmaceuticals commonly used in
Nigeria. Pharmaceutical samples in sixteen pharmacological groups in different dosage forms
were purchased from registered pharmacies and patent medicine shops from Abraka and
Obiaruku in Delta State, Nigeria. The samples were digested using a bi acid mixture of HNO3 and
HCIO4 in the ratio of 6:1 and analyzed using the Atomic Absorption spectrometer (AAS) for the
presence of lead, chromium, cadmium, zinc, nickel, manganese, iron, copper and cobalt. The
result reveals significant contamination by all the metals investigated with the exception of
copper and cobalt. The contamination may be attributed to wear and tear of manufacturing
machinery, contamination from water, packaging and raw materials. It is recommended that
machinery used for the manufacture of pharmaceuticals should be well maintained and replaced
were necessary and strict adherence to good manufacturing practice (GMP) as required by
regulatory agencies.