Lead and cadmium in infant milk and cereal based formulae marketed in Nigeria: a probabilistic non-carcinogenic human health risk assessment.

BACKGROUND: There has been concern on the likelihood of contamination of infant formulae and consequent health risk in children. OBJECTIVE: This study has assessed and compared the lead and cadmium levels in infant formulae commonly consumed in Nigeria with international regulatory limits. It has also compared the estimated daily intake with Joint FAO/WHO Expert Committee on Food Additives (JECFA) and Proposition 65 Provisional Tolerable Daily Intake. MATERIAL AND METHODS: Lead and cadmium levels in 26 different brands of infant formulae purchased from stores in Port-Harcourt, Rivers state, Nigeria in January 2018 were assayed by Atomic Absorption Spectrophotometry. RESULTS: The lead and cadmium levels in milk based infant formulae ranged from 0.61-3.50 mg/kg and 0.01-0.55 mg/kg respectively whereas the range of the lead and cadmium levels in the cereal and cereal mix based were 0.29-1.95 mg/kg and 0.02-0.37 mg/kg, and 0.47-2.34 mg/kg and 0.001-0.46 mg/kg respectively. The mean lead level in the milk-based formulae (1.49 0.89 mg/kg) was slightly higher than other groups of formulae but the difference was not significant (p<0.05). The mean level of cadmium (0.17 mg/kg) in milk-based infant formulae was higher than levels in cereal and cereal mix but there was no significant statistical difference (p<0.05) between the samples. The lead and cadmium level in milk, cereal and cereal mixed based infant formulae were above the food safe limits. CONCLUSIONS: The consumption of infant formulae may add to the body burden of cadmium and lead of children with attendant public health implication. Regular monitoring and safety assessment of metals contamination of these infant formulae is advised.

Safety of honey consumed in Enugu State, Nigeria: a public health risk assessment of lead and polycyclic aromatic hydrocarbons

Background: Information about lead (Pb) and polycyclic aromatic hydrocarbons (PAHs) concentrations in honey and their dietary intake is very important in human health risk assessment. Currently, there are paucity of data on the risk assessment and concentrations of lead and PAHs in honey in Nigeria. Objective: This study has determined the potential human health risk of lead and PAHs associated with the consumption of honey in Enugu state, Nigeria. Materials and methods: Lead and US EPA 16 priority PAHs in honey harvested from rural and urban communities in March 2016 were determined using Atomic Absorption Spectrometer and Gas Chromatograph respectively. Carcinogenic and non-carcinogenic risk assessments were carried. Results: The mean concentration of Pb in honey ranged from 0.005 mg/kg ­ 0.08 mg/kg. The mean concentrations of 16 PAHs in honey ranged from 4.71E-03 ­ 2.72 mg/kg. The dietary intake of the PAHs for adults and children ranged from 0.0021 ­ 0.0259 mg/kg/day and 0.0011 ­ 0.0129 mg/kg/day respectively. The levels of BaPeq and their margin of exposure MOE suggest non-significant health risk. The incremental life cancer risk ILCR of Pb were within safe range of <1E-04. Conclusion: Consumption of honey from Enugu State, Nigeria may not pose a significant health risk_

Childhood Drug and Non-Drug Poisoning in Nigeria: An Economic Appraisal.

BACKGROUND: The dearth of information on the economic cost of childhood poisoning in sub-Saharan Africa necessitated this study. OBJECTIVE: This study has investigated the prevalence of childhood drug and non-drug poisoning, treatment modalities and economic costs in Nigeria. METHOD: A retrospective study of childhood drug and non-drug poisoning cases from January 2007 to June 2014 in the University of Port Harcourt Teaching Hospital (UPTH), Port Harcourt, Nigeria was carried out. Medical records were analysed for demographic and aetiological characteristics of poisoned children (0-14 years of age), as well as fiscal impact of poisoning cases. FINDINGS: Of the 100 poisoned patients, 46% were male and 54% female, with female/male ratio of 1.17:1. Most of the children were under five years of age. Paracetamol, amitriptyline, chlorpromazine, ferrous sulphate, kerosene, organophosphates, carbon monoxide, snake bite, alcohol and rodenticides were involved in the poisoning. The average cost of poison management per patient was about $168, which is high given the economic status of Nigeria. CONCLUSION: Childhood poisoning is still a significant cause of morbidity among children in Nigeria and accounts for an appreciable amount of health spending, therefore preventive strategies should be considered.

Probabilistic health risk assessment of heavy metals in honey, Manihot esculenta, and Vernonia amygdalina consumed in Enugu State, Nigeria.

Honey is a nutritive fluid product of bees with an array of pharmacological/medicinal effects. As a natural product from honeybees, honey is regarded to be safe and free from any contaminants. Cassava tuber (Manihot esculenta)-based meal, Vernonia amygdalina (bitter leaf soup), and honey are common local cuisine in Nigeria. This is a human health risk assessment of heavy metals associated with the consumption of honey (Apis mellifera scutellata), cassava (Manihot esculenta), and bitter leaf (Vernonia amygdalina) in Enugu State, Nigeria. Concentrations of lead (Pb), Cd, As, Cu, Ni, Mn, Fe, Cr, and Fe in honey, soil, Manihot esculenta, and Vernonia amygdalina were determined using an atomic absorption spectrophotometer (AAS). The principal component analysis (PCA) was performed as a factor reduction technique among 12 factors (3 locations against 4 sources of heavy metals). The mean concentration of metals in honey, soil, Manihot esculenta, and Vernonia amygdalina ranged from 0.001 to 4.28 mg kg-1, from 0.0026 to 170.52 mg kg-1, from 0.012 to 80.63 mg kg-1, and from 0.0016 to 126.48 mg kg-1, respectively. Pb showed the highest carcinogenic risk with values of 3.18E-04-1.43E-01 in Vernonia amygdalina and 1.69E-04-3.47E-04 in Manihot esculenta for adults and children, respectively. In honey, Cd showed the highest carcinogenic risk with values of 1.26E-02-1.07E-01. About 51.5% of total cancer risk (TCR) was below 1E-04. Consumption of honey, Vernonia amygdalina, and Manihot esculenta in some urban parts of Enugu may pose some adverse health effects.

Unsafe herbal sex enhancement supplements in Nigerian markets: a human risk assessment.

High rates of irreversible oligo- or azoospermia are found among Nigerian men, leading many to consume herbal male sex enhancement products. The possibility of reproductive toxicity due to heavy metal contamination (Cr, As, Co, Hg, Cd, and Pb) of herbal products commonly used to boost libido or treat erectile dysfunction necessitated this study. In this study, herbal sex enhancement supplements were bought from pharmaceutical shops in Port Harcourt, Nigeria, and analyzed for heavy metals (Cr, As, Co, Hg, Cd, and Pb) contents using atomic absorption spectroscopy. The estimated daily metal intake (EDImetal), target hazard quotients (THQ), and total target hazard quotients (TTHQ) were determined. All the herbal sex enhancers used in this study contained heavy metals in these ranges: lead (0.032-0593), cobalt (0.025-0.075), cadmium (0.0011-0.048), and chromium (0.016-0.49) mg/kg. About 24.32% of the samples had TTHQ greater than 1. The EDImetal, THQ, and TTHQ of herbal sex enhancement supplements suggest that the use of some of these herbal sex enhancement supplements may not be risk-free after chronic exposure. Herbal sex enhancement supplements sold in Nigeria contain high levels of lead and cadmium. Since these metals are known to have male reproductive toxicity, these supplements may be adding to both the body burden of these metals and also implicated in the increasing incidence of male infertility in Nigeria.

Cosmetic Use in Nigeria May Be Safe: A Human Health Risk Assessment of Metals and Metalloids in Some Common Brands.

Twenty different brands of cosmetic products were purchased from supermarkets in Port Harcourt, Rivers State, Nigeria, with the aims to determine the levels of metals and assess the health risk to humans through long-term usage. The concentration of metals (arsenic, lead, mercury, cadmium, and nickel) in the cosmetic samples was measured with atomic absorption spectrophotometry after acid digestion. The concentration of metals in these brands of cosmetic studied ranged from As: 0.001-0.0161 mg/kg, Pb: 0.289-2.873 mg/kg, Hg: 0.001-0.0014 mg/kg, Cd: 0.001-0.334 mg/kg, and Ni: 0.007-2.748 mg/kg. The metal and metalloid contents were less than the regulatory limits set for both metal impurities and as color additives. The target hazard quotient, hazard index, and cancer risk were less than the acceptable limit, indicating a measure of safety. Cosmetics sold in Nigeria may not add to the body burden of metals and metalloids.

Health risk assessment and dietary exposure of polycyclic aromatic hydrocarbons (PAHs), lead and cadmium from bread consumed in Nigeria.

Objective: A risk assessment and dietary exposure to polycyclic aromatic hydrocarbons (PAHs), lead and cadmium from bread, a common food consumed in Nigeria. Material and Methods: Sixty samples of bread were collected from different types of bakeries where the heat is generated by wood (42 samples) or by electricity (18 samples) from twenty bakeries located in Gusau Zamfara (B1- B14) and Port Harcourt Rivers States (B15-B20) in Nigeria. PAHs in bread were determined by gas chromatography. Lead and cadmium were determined using atomic absorption spectrophotometry. Results: Non-carcinogenic PAHs pyrene (13.72 µg/kg) and genotoxic PAHs (PAH8), benzo[a]anthracene (9.13 µg/ kg) were at the highest concentrations. Total benzo[a]pyrene concentration of 6.7 µg/kg was detected in 100% of tested samples. Dietary intake of total PAHs ranged between 0.004-0.063 µg/kg bw. day-1 (children), 0.002-0.028 µg/kg day-1 (adolescents), 0.01-0.017 µg/kg day-1 (male), 0.002-0.027 µg/kg day-1 (female), and 0.002-0.025 µg/kg day-1 (seniors). The Target Hazard Quotient (THQ) for Pb and Cd were below 1. Lead ranged from 0.01-0.071 mg/kg with 10.85 and 100% of bread samples violating the permissible limit set by USEPA, WHO and EU respectively. Cadmium ranged from 0.01-0.03 mg/kg, with all bread samples below the permissible limits as set by US EPA, JECFA and EU. The daily intake of Pb and Cd ranged from 0.03-0.23 µg/kg bw day-1 and 0.033-0.36 µg/kg bw day-1 respectively. Incremental lifetime cancer risk (ILCR) was 3.8 x 10-7. Conclusions: The levels of these contaminants in bread if not controlled might present a possible route of exposure to heavy metals and PAHs additional to the body burden from other sources.

Lead Levels in Vegetables from Artisanal Mining Sites of Dilimi River, Bukuru and Barkin Ladi North Central Nigeria: Cancer and Non-Cancer Risk Assessment

Lead (Pb) contamination of foods and especially of frequently consumed vegetables is a growing public health concern worldwide. Although levels of exposure in developed countries have declined over the past decades, the same cannot be said of developing countries. Health risk assessment has increasingly been employed to determine the potential hazard of heavy metal exposure to humans. In this study vegetable samples (tomatoes, red pepper, brown beans, lettuce, cabbage, Irish potatoes, onions, green beans and carrot), soil samples, irrigation water and sediment samples were collected from the Dilimi River, Bukuru and Barkin Ladi communities in north central Nigeria and analyzed for Pb content using atomic absorption spectroscopy. The results showed levels with ranges from 0.5 ­ 2.4 mg/kg (Dilimi River), 0.3 ­ 1.7 mg/kg (Barkin Ladi) and 1.46 ­ 1.89 mg/kg (Bukuru) in vegetables were largely above the maximum permissible limit recommended by WHO/FAO. The lead levels found in soil samples, which ranged from 9.19 ­ 36.042 mg/kg, also exceeded some safety standards. At least 75% of the calculated estimated daily intakes of Pb from different vegetable samples were also higher than the permissible tolerable daily intakes PTDI (0.0035 mg/kg day-1) of Pb in both adults and children. Target hazard quotient THQ values > 1 were also observed in children. In conclusion, there is a health risk from consumption of vegetables in these mining communities.

Polycyclic Aromatic Hydrocarbons In Edible Mushrooms from Niger Delta, Nigeria: Carcinogenic and Non-Carcinogenic Health Risk Assessment

In the oil-rich Niger Delta, hydrocarbon pollution and oil spillages, gas flaring and sundry anthropogenic activities constitute sources of polycyclic aromatic hydrocarbons (PAHs), with food contamination playing a major role in human exposure. In this study we assessed PAH levels in wild and cultivated edible mushroom species consumed by the general population from the oil producing Niger Delta, Nigeria. The concentrations of USEPA-16 PAHs were determined by gas chromatography and carcinogenic and non-carcinogenic health risks were calculated. The concentrations of USEPA-16 PAHs ranged from 0.02 mg/kg ­ 3.37 mg/kg. The dietary intake of carcinogenic and non-carcinogenic USEPA-16 PAHs (Naphthalene, Acenaphthylene, Acenaphthene, Anthracene, Phenanthrene, Flourene, Flouranthene, Pyrene, Benzo[a]Anthracene, Chrysene, Benzo[a]Pyrene, Benzo[b]Flouranthene, Benzo[K]Flouranthene, Benzo[g,h,i] Perylene, Dibenz[a,h]Anthracene and Ideno[1,2,3-cd]Pyrene) for adults, adolescents and seniors ranged from 0.00 ­ 0.05 mg/kg/day, 0.00 ­ 0.06 mg/kg/day and 0.00 ­ 0.07 mg/kg/day. The BaPeq ranged from 0.02 ­ 2.76 with margin of exposure MOE values of BaP ranging from 3,500,000 to 700,000, 3,500,000 and 3,500,000 to 7,000,000 for adults, adolescents and seniors indicating very insignificant health risk. The incremental lifetime cancer risk was within the safe range of 1.56x10-8 ­ 1.73x10-6 with the highest calculated risk found for wild Pleurotus ostreatus mushroom species from the study area.

Human health risk assessment of lead, manganese and copper from scrapped car paint dust from automobile workshops in Nigeria.

The economic downturn in Nigeria and Structural Adjustment Programme led to the flooding of Nigerian market with imported used automobiles. Most of these vehicles needed refurbishing and reworking. The present study is a human health risk assessment of metal exposure resulting from reworking of imported used vehicles in Nigeria. Scrap paint dusts from 56 Japanese made cars were collected from 8 different mechanic villages (workshops A-H] in Southeastern Nigeria. Scrap paints were homogenized, mixed, divided into fine particles and digested by standard method. The filtrates were assayed of lead, manganese and copper with atomic absorption spectrophotometry (AAS). Workshop B has the highest concentration of Pb (4.26 ± 0.93). Manganese in workshops A and F were (3.31 ± 0.85) and (3.04 ± 0.47) respectively and were higher than the levels from workshops C, B, D, G and H. Copper in workshop D (7.11 ± 0.21) was significantly greater than the other workshops. The highest hazard quotient (HQ) through ingestion, inhalation and dermal exposures in adults were 9.44E-05 (workshop B), 4.20E-01 (workshop B) and 1.08E-05 (workshop D) respectively. The highest values for HQ through ingestion, inhalation and dermal in children were 8.82E-04, 7.61E-01 and 2.86E-05 all in workshop B respectively. For children, the highest carcinogenic risk levels were 7.05E-08, 6.09E-05 and 2.29E-10 for ingestion, inhalation and dermal exposures respectively. In adults, the carcinogenic risk levels were 7.55E-09, 3.39E-05 and 8.67E-10 for ingestion, inhalation and dermal exposures respectively. Chronic exposure to scrap car paint dusts may be of significant public health importance in Nigeria as this may add to the body burden of some heavy metals.

Health risks from lost awareness of cultural behaviours rooted in traditional medicine: An insight in geophagy and mineral intake.

The term geophagy is applied to the recurrent intentional eating of soil with multifactorial motivation. Geophagists are generally defined by gender (women), age (children), physical status (e.g. pregnancy, lactation, postpartum), social status (people exposed to significant nutritional deficiencies), and culture, but lost awareness of traditional medical meaning of this practice is changing these consumption patterns and increasing health risks. Moreover, although the holistic anthropological perspective recognizes soil consumption as mineral supplementation under certain circumstances, we should consider how the living environment has changed and is changing, along with diet, nutrition requirements, and habits. Therefore, benefits-to-risks ratio of cultural behaviours initiated centuries ago based on traditional medical practices requires deep revision and assessment. Knowledge on minerals metabolism, bioavailability and interactions is required to properly assess the role of geophagy in a balanced and safe intake of micronutrients. Most important, the risk of unbalanced intake of minerals may be serious since the mineralogy and chemistry of geophagic clays are uncontrolled, variable, and difficult to standardize. In addition, other factors (radioactive materials, organic chemicals and soil pathogens) complicate the risk assessment for population groups consuming soil. Since the geophagic practice is expected to persist despite economic development, the paper discusses the multifaceted spectrum of geophagy to highlight critical aspects for risk management.

Use of Bisphenol A-containing baby bottles in Cameroon and Nigeria and possible risk management and mitigation measures: community as milestone for prevention.

The plasticizer Bisphenol A (BPA) is banned in baby bottles in many industrialized countries due to safety concerns. We provide a pilot view on the potential BPA exposure of bottle-fed children in sub-Saharan Africa through an enquiry on availability, accessibility and affordability of plastic baby bottles, usage pattern, and risk perception. An observational survey was conducted in a randomized group of vending sites (34 pharmacies; 87 shops and markets), in three cities (Yaoundé, Foumbot, Bafoussam) in Cameroon (two regions), and in two cities (Lagos, Port Harcourt) in Nigeria (two states). Interviews in vending sites and group discussions were conducted with 248 mothers. Cameroon and Nigeria showed a largely comparable situation. Plastic baby bottles are largely imported from industrialized countries, where a label indicates the presence/absence of BPA. In pharmacies most plastic baby bottles are labeled as BPA-free, whereas most bottles sold in shops are not BPA-free. BPA-containing bottles are more accessible and affordable, due to sale in common shops and lower costs. The meaning of the label BPA-free is unknown to both vendors and customers: the BPA issue is also largely unknown to policy makers and media and no regulation exists on food contact materials. The wide availability of BPA-containing baby bottles, lack of information and usage patterns (e.g. temperature and duration of heating) suggest a likely widespread exposure of African infants. Possible usage recommendations to mitigate exposure are indicated. Risk communication to policy makers, sellers and citizens is paramount to raise awareness and to oppose possible dumping from countries where BPA-containing materials are banned. Our pilot study points out relevant global health issues such as the capacity building of African communities on informed choices and usage of baby products, and the exploitation of international knowledge by African scientists and risk managers.

Heavy metals health risk assessment for population via consumption of food crops and fruits in Owerri, South Eastern, Nigeria.

BACKGROUND: This study assessed lead, cadmium, and nickel level in food crops, fruits and soil samples from Ohaji and Umuagwo and Owerri in South Eastern Nigeria and estimated the potential health risks of metals. Samples were washed, oven-dried at 70-80°C for 24 h and powdered. Samples were digested with perchloric acid and nitric acid. Metals were analysed with Unicam Atomic Absorption Spectrophotometer. RESULT: The concentration of Pb, Cd, and Ni in Ohaji exceeded the maximum allowable concentrations for agricultural soil as recommended by EU. Lead, Cd, and Ni in the food crops were highest in Oryza sativa, Glycine max, and Pentabacta microfila respectively. Highest levels of Pb, Cd, and Ni, in fruits were detected in Canarium schweinfurthii, Citrus reticulata, Ananas comosus respectively. The true lead and cadmium intake for the rice based meal were 3.53 and 0.034 g/kg respectively. Whereas the true intake of lead and cadmium for the cassava based meal were 19.42 and 0.049 g/kg respectively. CONCLUSION: Local food stuff commonly available in South Eastern Nigeria villages may contribute to the body burden of heavy metal. This is of public health importance.

Water-quality issues in the Niger Delta of Nigeria: a look at heavy metal levels and some physicochemical properties.

INTRODUCTION: Water contamination is a notable environmental problem of the Niger Delta, Nigeria. The present work is an improved attempt at a scientific discourse of water-quality issues in the Niger Delta of Nigeria with respect to heavy metal levels in surface water in view of the hitherto dearth of scientific data. MATERIALS AND METHODS: We have looked at the Fe, Mn, Cu, Cd, Cr, Pb, Ni, Zn (quantified by atomic absorption spectrophotometry) profiles and some physicochemical properties (pH and salinity) of some surface water used by the local population in the mid Niger Delta. Surface water samples were collected from these surface waters in the dry and rainy seasons. RESULTS: Akiplai wellhead stream and Etebde River had the highest level of iron. In Delta State, high levels of cadmium were found in Ijala creek, Ubeji creek, Jeddo River, and Ekpan River, respectively. High lead levels were seen in Jeddo River, Ekurede-Itsekiri Creek, and Ughelli River. In River State, Tombia River had the highest levels of chromium, lead, and nickel. Ijala creek, Eja-Etan, Ifie-Kporo, Ubeji Creek, Jeddo, Ekpan Rivers, and Ekurede-Itsekiri Creek, all in Delta State, presented highest salinity levels. Orash River, Ughewhe stream, and Egbo stream have a lowest pH of 5.22, 5.32, and 5.53, respectively, while Ifie-Kporo River have a highest pH of 8.18. CONCLUSION: Most of the metal levels were above US EPA Maximum Contaminant Level MCL indicative of water pollution which may be of public health importance, and we, therefore, recommend water-quality monitoring.

Assessment of environmental distribution of lead in some municipalities of South-Eastern Nigeria.

Lead (Pb) levels were measured in roadside surface soils, dust particles and rain water samples from the urban cities of Enugu, Awka, Onitsha, Nnewi, Aba, Port Harcourt and Warri in Southern Nigeria in 2007 and 2008. Samples were collected during the dry season, while rain water samples were collected during the early rain (April-June), mid rain (July-August) and late rain seasons (September-October) for the two years. Soil samples were collected from traffic congested roads, dust was collected by tying a plastic basin on a pole 1.5 m above ground level and leaving it for 45 days. Rain samples were collected from three equidistant points. Samples were analyzed by AAS. The highest soil Pb of 120.00 +/- 0.00 and 80.36 +/- 0.00 mg/kg were reported in Onitsha for 2007 and 2008, respectively. Nnewi showed 33.40 +/- 0.01 and 4,238.29 +/- 0.00 mg/kg for 2007 and 2008. Aba had 22.56 +/- 0.01 and 21.28 +/- 0.00 mg/kg for 2007 and 2008. Higher concentrations were recorded for Nnewi and Port Harcourt in 2008 than in 2007. Enugu had more in 2007 while Awka had more in 2008. Dust Pb ranged from 0.13-0.49 mg/kg and 0.15-0.47 mg/kg for 2007 and 2008, respectively. Rain samples had the least Pb concentration, ranging from 0.103 +/- 0.000 to 0.163 +/- 0.046 mg/L. We may conclude that Nigerians are exposed to environmental Pb.

Environmental pollution and blood lead levels in Nigeria: who is unexposed?

While blood lead levels (BLLs) in many western countries have progressively declined since 1976, in Nigeria high BLL continue to be documented not only in exposed workers but also in "unexposed" control subjects. The problem of environmental lead exposure has hitherto gone unaddressed by both researchers and health policy makers in Nigeria despite the immense public health importance. Continued high BLLs in Nigeria cast doubt on researchers' ability to find real "unexposed control subjects" in future studies, and point to the importance of controlling environmental lead exposures.