Concentrations and Hazards of Polycyclic Aromatic Hydrocarbons in Hawked Baked Ready-to-Eat Foods in Nigeria

The total concentrations of the Ʃ16 polycyclic aromatic hydrocarbons (PAHs) were examined in some samples of baked ready-to-eat foods (cake, sausage roll, meat pie, burger, and bread) with a view to provide information on the hazards associated with the consumption of these hawked street foods. The measurements were performed by using a gas chromatograph-mass spectrometer (GC-MS) after hexane/dichloromethane extraction and clean-up. The total concentrations of the PAHs in these samples of ready-to-eat baked foods ranged from 427.4 to 1224 μg kg–1, 289.9 to 853.7 μg kg–1, 574.4 to 2333 μg kg–1, 364.6 to 2906 μg kg–1, and 15.7 to 213.1 μg kg–1 for cake, sausage roll, meat pie, burger, and bread, respectively. The results indicated that these baked ready-to-eat foods were mainly contaminated with 2-, 3-, and 4-ring PAHs. The concentrations of benzo(a)pyrene were less than 0.1 μg kg–1 in nineteen out of the twenty samples examined

Concentrations and Hazards of Polycyclic Aromatic Hydrocarbons in Hawked Baked Ready-to-Eat Foods in Nigeria

The total concentrations of the Ʃ16 polycyclic aromatic hydrocarbons (PAHs) were examined in some samples of baked ready-to-eat foods (cake, sausage roll, meat pie, burger, and bread) with a view to provide information on the hazards associated with the consumption of these hawked street foods. The measurements were performed by using a gas chromatograph-mass spectrometer (GC-MS) after hexane/dichloromethane extraction and clean-up. The total concentrations of the PAHs in these samples of ready-to-eat baked foods ranged from 427.4 to 1224 μg kg–1, 289.9 to 853.7 μg kg–1, 574.4 to 2333 μg kg–1, 364.6 to 2906 μg kg–1, and 15.7 to 213.1 μg kg–1 for cake, sausage roll, meat pie, burger, and bread, respectively. The results indicated that these baked ready-to-eat foods were mainly contaminated with 2-, 3-, and 4-ring PAHs. The concentrations of benzo(a)pyrene were less than 0.1 μg kg–1 in nineteen out of the twenty samples examined

Concentrations and exposure risks of some metals in facial cosmetics in Nigeria

The concentrations of nine metals (Cd, Pb, Ni, Cr, Co, Cu, Fe, Mn and Zn) were determined in lip sticks, lip glosses, lip balms, eye pencils, eyeliners, eye shadows, blushes, mascaras and face powders. The study was aimed at providing information on the risk associated with human exposure to metals in these facial cosmetic products. The concentrations of metals in the samples were measured by atomic absorption spectrometry after digestion with a mixture of nitric acid, hydrochloric acid and hydrogen peroxide. The mean concentrations of metals in these facial cosmetics ranged from 3.1 to 8.4 μg g−1 Cd, 12–240 μg g−1 Pb, 9.1–44 μg g−1 Cr, 18–288 μg g−1 Ni, 1.6–80 μg g−1 Cu, 7.9–17 μg g−1 Co, 2.3–28 mg g−1 Fe, 12–230 μg g−1 Mn, and from 18 to 320 μg g−1 Zn. The concentrations of Ni, Cr and Co were above the suggested safe limit of 1 μg g−1 for skin protection, while Cd and Pb were above the Canadian specified limits. The systemic exposure dosage (SED) values for these metals obtained from the use of these facial cosmetic products were below their respective provisional tolerable daily intake (PTDI)/or recommended daily intake (RDI) values. The margin of safety values obtained were greater than 100 which indicated that the concentrations of the metals investigated in these facial cosmetics do not present considerable risk to the users except in the case of face powders. Keywords: Metals, Facial cosmetics, Systemic exposure dosage, Margin of safety, Allergic contact dermatiti

Evaluation of human exposure to metals from some commonly used hair care products in Nigeria

The concentrations of nine metals, namely, cadmium (Cd), lead (Pb), chromium (Cr), copper (Cu), cobalt (Co), nickel (Ni), manganese (Mn), zinc (Zn), and iron (Fe), were determined in 26 brands of hair care products including hair relaxers, conditioners and shampoos. The study was aimed at providing information on the possible risks arising from heavy metals associated with the use of these products. The concentrations of the metals were determined by means of atomic absorption spectrophotometry after digestion of the samples with a mixture of acids. The concentrations of the respective metals in hair relaxers, shampoos and conditioners were found to be 0.8–2.5, 0.6–3.0, <LOQ-2.8 μg g−1 Cd; 4.5–26.0, <LOQ-28.0, <LOQ-425 μg g−1 Pb; <LOQ-0.6, <LOQ-3.4, <LOQ-4.2 μg g−1 Cr; <LOQ-3.5, <LOQ-6.0, <LOQ-3.5 μg g−1 Cu; <LOQ-7.0, <LOQ-7.0, 0.5–4.5 μg g−1 Co; 1.0-5.5, <LOQ-10.5, 1.5–6.0 μg g−1 Ni; <LOQ-9.0, 2.0–25.5, <LOQ-15 μg g−1 Mn; 36.5–48.0, 35.5–1080 μg g−1, 30.0–69.0 μg g−1 Zn; and 84.5–123, 66.7–284, 57.6–153 μg g−1 Fe respectively. The systemic exposure dosage (SED) values of the studied metals were below their respective provisional tolerable daily intakes (PTDI)/recommended daily intakes (RDI), while the margins of safety were greater than 100 which indicate that these products are safe to use. Keywords: Metals, Systemic exposure dosage, Margin of safety, Risk assessment, Hair care products, Nigeri