Abstract:
The level of heavy metals, lead (Pb) and arsenic (As) were determined in nine brands of locally produced (Nigerian) rice and nine imported rice brands from Thailand, India and China. The heavy metal analysis was conducted using atomic absorption spectrometry of digested, parboiled rice samples. The findings showed combined mean values of lead in local and imported rice brands as follows: 0.19 mg/kg and 0.11 mg/kg. All the values of lead concentration in both local and imported rice brands fall within the baseline of the maximum allowable concentration (MAC) value, 6.0 mg/kg specified by JECFA/EPSA for heavy metal (lead) in cereals and vegetables. The mean values of arsenic observed in local and imported rice brands was 4.42 mg/kg and 3.71 mg/kg respectively, which is far above maximum allowable concentration (MAC) value, 1.4 mg/kg stipulated by JECFA/EPSA for heavy metal (arsenic) in cereals and vegetables. This result shows that there might be serious risk of arsenic poising (acute or chronic) when these rice brands are consumed at the national average per capita level of 24.8 kg per annum, especially in children who are more susceptible to arsenic toxicity
