Food and drinking water are poorly delineated sources of human exposure to chemical food mutagens and endocrine-disrupting chemicals. In this study, the authors investigated the presence of mutagens and chemicals exhibiting oestrogenic activity in the daily diet of Nigerians, using in vitro assays. Commercially processed foods or snacks and various brands of pure water sachets were extracted by solid-phase extraction and liquid-liquid extraction, respectively. Mutagenicity was determined by the conventional Ames test and two complementary assays on two strains of Salmonella (TA 100 and TA 98), while the oestrogenic activity was assessed by a yeast bioluminescent assay, using two recombinant yeast strains (Saccharomyces cerevisiae BMAEREluc/ER? and S. cerevisiae BMA64/luc). A third of the food varieties investigated (chin-chin, hamburger, suya and bean cake) were mutagenic in all three assays, either in the presence or absence of S9 mix. Of the packed water samples, five out of the sixteen investigated (31%), were found to be oestrogenic, with oestradiol and bisphenol A equivalents ranging from 0.79 to 44.0 ng/L and 124.2 to 1,000.8 ng/L, respectively. Hence, although the current situation in Nigeria does not appear to be substantially worse than, in Europe, regular monitoring is warranted in the future.
Authors: Omoruyi IM, Ahamioje D, Pohjanvirta R. ;Full Source: International Journal of Environmental Research & Public Health. 2014 Aug 15;11(8):8347-67. doi: 10.3390/ijerph110808347. ;