Effect of Mercury on the Proximate Composition of Maize (Zea mays L.)

Boadi, N. O.; Okyere, H.; Badu, M.; Mensah, J. K.; Owusu-Appiah, I.

2013

English

Plants can be exposed to mercury either by direct administration as antifungal agents, mainly to crop plants through seed treatment or foliar spray, or by accident. Mercury poisoning has become a problem of interest on a global scale. Natural emissions of mercury form two-thirds of the input; man-made releases form about one-third. Significant amounts of mercury may be added to agricultural land with sludge, fertilizers, lime and manures. Total mercury levels were determined in six breeds of quality protein maize using cold vapor atomic absorption spectrometry (CVAAS). The breeds analyzed were Aziga, Abeleehi, Akposoe, Golden Jubilee, Etubi and Obaatanpa. Proximate composition of these breeds was also determined. The objective of this study was therefore to assess the effect of mercury on the proximate composition of quality protein maize. The proximate composition of the maize varieties analyzed showed that the moisture content ranged from 11.57% ± 0.205% to 12.76% ± 0.042%, ash from 1.11% ± 0.064% to 1.58% ± 0.021%, protein, 6.51% ± 0.307% to 10.39% ± 0.306%, fiber 1.44% ± 0.071% to 1.87% ± 0.057%, fat 1.84% ± 0.078% to 2.75% ± 0.092% and carbohydrate 71.77% ± 0.035% to 76.54% ± 0.216%. The total mercury levels in the maize breeds analyzed ranged from 0.0010 ± 1.17E-05 μg/g to 0.0079 ± 1.00E-05 μg/g. The mercury levels detected were lower than the WHO limit for mercury in food of 0.5 μg/g in all the maize breeds. The low levels of mercury in the maize samples show they are safe for consumption.

Boadi, N. O.; Okyere, H.; Badu, M.; Mensah, J. K.; Owusu-Appiah, I.