Skip to Content
Merck

Dietary exposure of Nigerians to mutagens and estrogen-like chemicals.

International journal of environmental research and public health (2014-08-26)
Iyekhoetin Matthew Omoruyi, Derek Ahamioje, Raimo Pohjanvirta
ABSTRACT

Food and drinking water are poorly delineated sources of human exposure to chemical food mutagens and endocrine-disrupting chemicals. In this study, we investigated the presence of mutagens and chemicals exhibiting estrogenic 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 estrogenic activity was assessed by a yeast bioluminescent assay, using two recombinant yeast strains (Saccharomyces cerevisiae BMAEREluc/ERα 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 estrogenic, with estradiol 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, e.g., in Europe, regular monitoring is warranted in the future.

MATERIALS
Product Number
Brand
Product Description

Supelco
Benzo[a]pyrene, certified reference material, TraceCERT®, Manufactured by: Sigma-Aldrich Production GmbH, Switzerland
Sigma-Aldrich
β-Nicotinamide adenine dinucleotide phosphate sodium salt, pkg of 5 mg (per vial)
Sigma-Aldrich
β-Nicotinamide adenine dinucleotide phosphate sodium salt, pkg of 10 mg (per vial)
Supelco
Benzo[a]pyrene, analytical standard, for environmental analysis
Sigma-Aldrich
Magnesium chloride hexahydrate, 99.995% trace metals basis
Supelco
Bisphenol A, certified reference material, TraceCERT®, Manufactured by: Sigma-Aldrich Production GmbH, Switzerland
Sigma-Aldrich
Magnesium sulfate solution, BioUltra, for molecular biology
Sigma-Aldrich
Bisphenol A, 97%
Sigma-Aldrich
Potassium phosphate dibasic, anhydrous, for luminescence, for molecular biology, BioUltra, ≥99.0% (T)
Sigma-Aldrich
Citric acid monohydrate, puriss. p.a., ACS reagent, reag. ISO, reag. Ph. Eur., buffer substance, 99.5-102%
Sigma-Aldrich
Nitrogen, ≥99.998%
Sigma-Aldrich
Dimethyl sulfoxide, anhydrous, ≥99.9%
Sigma-Aldrich
Citric acid monohydrate, puriss., meets analytical specification of Ph. Eur., BP, USP, E330, 99.5-100.5% (based on anhydrous substance), grit
Sigma-Aldrich
Magnesium sulfate, ≥99.99% trace metals basis
Sigma-Aldrich
Magnesium chloride hexahydrate, BioUltra, ≥99.0% (KT)
Sigma-Aldrich
8-Octanoyloxypyrene-1,3,6-trisulfonic acid trisodium salt, suitable for fluorescence, ≥90% (HPCE)
Sigma-Aldrich
Dimethyl sulfoxide, BioUltra, for molecular biology, ≥99.5% (GC)
Sigma-Aldrich
Magnesium chloride hexahydrate, BioUltra, for molecular biology, ≥99.0% (KT)
Sigma-Aldrich
Dimethyl sulfoxide, sterile-filtered, BioPerformance Certified, meets EP, USP testing specifications, suitable for hybridoma
Supelco
Bisphenol A, ≥99%
Sigma-Aldrich
Magnesium chloride hexahydrate, tested according to Ph. Eur.
Sigma-Aldrich
Potassium phosphate dibasic, 99.95% trace metals basis
Sigma-Aldrich
2-Aminoanthracene, 96%
Supelco
Dimethyl sulfoxide, analytical standard
Sigma-Aldrich
Estradiol, meets USP testing specifications
Sigma-Aldrich
β-Estradiol, ≥98%
Sigma-Aldrich
β-Nicotinamide adenine dinucleotide phosphate hydrate
Sigma-Aldrich
Magnesium chloride hexahydrate, BioXtra, ≥99.0%
Sigma-Aldrich
Potassium phosphate dibasic solution, 1.0 M
Sigma-Aldrich
Citric acid monohydrate, BioXtra, ≥99.5%