RISK ASSESSMENT OF METALS AND METALLOIDS IN COSMETIC IN NIGERIA 433 for the studied metals was used to derive their respective NOAEL values. The RFD is defi ned as an estimate of the daily exposure to the human population (including sensitive subgroups) that is likely to be without an appreciable risk of deleterious effects during lifetime. Hence, the relation between NOAEL and RFD is NOAEL = RFD × UF × MF, where UF and MF are the uncertainty factors (refl ecting the overall confi dence in the various datasets) and modifying factors (based on the scientifi c judgment used), respec- tively. In this case, the default values of UF and MF are 100 and 1, respectively. The RFDs (in mg/kg/d) used are shown in Table V. The World Health Organization (WHO) pro- posed a minimum value of 100, and it is generally accepted that MoS should at least be 100 to conclude that a substance is safe for use (14). The SCCS also noted the fact that in many convection computations of MoS, the oral bioavailability of the substance is as- sumed to be 100% if oral absorption data are available. However, it is considered appro- priate to assume that not more than 50% of an orally administered dose is systemically available (14). For the purpose of this study, two scenarios were considered, i.e., dermal absorption of the metal not exceeding 50% and 100% of the measured concentrations of the substance in the cosmetic products. RESULTS Table III shows the concentrations of heavy metals, namely, As, Pb, Hg, Cd, and Ni, re- spectively. The concentration of As ranged from 0.001 to 0.016 mg/kg. Least heavy metal concentration of arsenic was found in Authentic herbal cream, Cyndy herb crystal, New Jerusalem, Dr Elechi omega 7, and Heel herbal, whereas the highest concentration of arsenic was found in Aquasulf. Fifty-fi ve percent of samples had concentrations of Arsenic less than the detectable limit, whereas 45% had concentrations between 0.001 and 0.016. Pb concentration was 0.283 mg/kg and 2.873 mg/kg in heel balm and Tee Tee 3 d, re- spectively. Ten percent of the samples, namely Chioral restoration and Lip balm feel, had concentrations of Pb that were in the detectable limit. Thirty percent of the samples had concentrations less than 1.000 mg/kg, whereas 60% of the cream samples had concentra- tions greater than 1.000 mg/kg. The concentration of Hg in the cream samples ranged from 0 to 0.001 mg/kg. Seventy- fi ve percent of the samples had concentrations of Hg less than the detectable limit, whereas 25% of the samples had Hg concentrations of 0.001 mg/kg. Cadmium concentration in the cream samples stood at 0.001–0.334 mg/kg in Candy anti-spot and Chioral restoration. Notably, 45% of the samples had Cd concentration less than the detectable limit, whereas 55% had concentrations less than 1.000 mg/kg. Table II Product Type and Parameters Used for Calculation of Systemic Exposure Dose (14) Product type AA (amount applied in gram) SSA (skin surface area in cm2) F (frequency in day) RF (retention factor) Body cream 7.82 15,670 2.28 1.0 Facial cream 1.54 565 2.14 1.0 Hand cream 2.16 860 2 1.0 Lip balm 0.057 4.8 2 1.0 Hair cream 4.0 1,010 1.14 0.1

JOURNAL OF COSMETIC SCIENCE 434 Table III Metal Concentration in Cosmetics (mg/kg) S/N Sample identity As Pb Hg Cd Ni Σ Metals 1 BJ 7 d ND 1.694 0.001 0.042 0.798 2.535 2 Tee Tee 3 d ND 2.873 ND 0.255 0.842 3.97 3 Aquasulf 0.016 2.607 ND 0.276 1.163 4.046 4 Skin Guard Aloe vera 0.012 2.827 ND 0.171 1.389 4.387 5 Acrec way ND 1.056 ND 0.069 2.745 3.87 6 Ceedym acne 0.002 1.774 ND ND 0.411 2.185 7 Authentic herbal cream 0.001 0.896 0.001 ND 0.872 1.769 8 Chioral restoration ND ND ND 0.334 ND 0.334 9 Magic herb ND 1.669 ND ND 1.323 2.992 10 Cyndy herb crystal 0.001 0.769 ND ND 0.596 1.365 11 New Jerusalem 0.001 1.437 ND 0.006 0.372 1.815 12 Dr Elechi omega 7 0.001 1.026 0 ND 2.492 3.518 13 Grace palm herbal balm ND 0.428 0.001 ND 1.673 2.102 14 Anti-wrinkles cream 0.002 2.116 ND 0.011 1.946 4.073 15 Hip up cream ND 1.367 ND 0.003 0.748 2.118 16 Hand D cream ND 0.695 ND 0.001 1.192 1.888 17 Heel balm 0.001 0.283 ND 0.005 0.348 0.636 18 Lip balm feel ND ND ND ND 0.94 0.94 19 Deep relief ND 1.422 ND ND 0.413 1.835 20 Candy anti-spot ND 0.647 0.001 ND 0.287 0.935 As: arsenic, Pb: lead, Hg: mercury, Cd: cadmium, Ni: nickel. Nickel in the cream samples ranged from 0.287 to 2.745 mg/kg in Candy anti spot and Acreway, respectively. Fifty-fi ve percent of the creams’ samples had concentrations less than 1.000 mg/kg and 40% had concentrations greater than 1.000 mg/kg, whereas only Chioral restoration had concentration less than the detectable limit. In all 20 cream samples, the total analyzed metal concentration ranged from 0.334 mg/ kg in Chioral restoration to 4.387 mg/kg in Skin guard aloe vera. Twenty percent of the cream samples had concentrations of analytes less than 1.000 mg/kg, whereas 80% had concentrations greater than 1.000 mg/kg (1.000–4.387 mg/kg). Table IV shows the CDE from heavy metals in the creams. The CDE to arsenic ranged from 4.22E-10 to 6.75E-09 mg/kg/d for adults and 4.14E-10 to 6.63E-09 mg/kg/d for children. The highest CDE to arsenic was from Aquasulf. The CDE to Pb from the cream ranged from 9.28E-09 to 9.42E-08 mg/kg/d and 9.12E- 09 to 9.26E-08 mg/kg/d for adults and children, respectively. The least CDE value due to Pb exposure was found in Heel balm, whereas the highest CDE value for Pb was found in Tee Tee 3 d. The CDE ranges for Hg, Cd, and Ni were 3.28E-11–0 mg/kg/d and 3.22E-12–0 mg/kg/d, 4.41E-11–4.69E-09 mg/kg/d and 1.38E-11–4.61E-09 mg/kg/d, and 4.03E-09–3.50E-08 mg/kg/d and 3.96E-09–3.44E-08 mg/kg/d for adults and children, respectively. The least CDEs from Cd and Ni were found in hand cream and candy anti spot, respectively, whereas the highest CDEswere found in Chioral restoration and Dr Elechi omega 7. Table V shows the noncarcinogenic risk, namely, target HQ (THQ) and hazard indices, respectively. The THQ ranged from As exposure was 2.53E-13–2.02E-12 and 2.49E- 13–1.99E-12 for adults and children, respectively.