Polycyclic Aromatic Hydrocarbons in Soil and Vegetation of Niger Delta, Nigeria: Ecological Risk Assessment.

The Niger Delta, Nigeria, is noted for crude oil exploration. Whereas there seems to be a handful of data on soil polycyclic aromatic hydrocarbon (PAH) levels in this area, there is a paucity of studies that have evaluated soil and vegetation PAHs simultaneously. The present study has addressed this information gap. Fresh Panicum maximum (Jacq) (guinea grass), Pennisetum purpureum Schumach (elephant grass), Zea mays (L.) (maize), and soil samples were collected in triplicate from Choba, Khana, Trans-Amadi, Eleme, Uyo, and Yenagoa. PAHs determination was carried out using GC-MS. The percentage composition of the molecular weight distribution of PAHs, the molecular ratio of selected PAHs for identification of possible sources, and the isomeric ratio and total index of soil were evaluated. Pennisetum purpureum Schumach (elephant grass) from Uyo has the highest (10.0 mg·kg-1) PAH while Panicum maximum (Jacq) (guinea grass) has the highest PAH (32.5 mg·kg-1 from Khana. Zea mays (L.) (maize) from Uyo (46.04%), Pennisetum purpureum Schumach (elephant grass) from Trans-Amadi (47.7%), guinea grass from Eleme (49.2%), and elephant grass from Choba (39.9%) contained the highest percentage of high molecular weight (HMW) PAHs. Soil samples from Yenagoa (53.5%) and Khana (55.3%) showed the highest percentage of HMW PAHs. The total index ranged 0.27-12.4 in Uyo, 0.29-8.69 in Choba, 0.02-10.1 in Khana, 0.01-5.53 in Yenagoa, 0.21-9.52 in Eleme, and 0.13-8.96 in Trans-Amadi. The presence of HMW PAHs and molecular diagnostic ratios suggest PAH pollution from pyrogenic and petrogenic sources. Some soils in the Niger Delta show RQ(NCs) values higher than 800 and require remediation to forestall ecohealth consequences.

E-WASTE threatens health: The scientific solution adopts the one health strategy.

The aggressively extractive advanced technology industry thrives on intensive use of non-renewable resources and hyper-consumeristic culture. The environmental impact of its exponential growth means extreme mining, hazardous labour practices including child labour, and exposure burden to inorganic and organic hazardous chemicals for the environment and current and future human generations. Globally, processes such as in-country reduce, reuse and recycle have so far received less attention than outer-circle strategies like the uncontrolled dumping of e-waste in countries that are unprotected by regulatory frameworks. Here, in the absence of infrastructures for sound hazardous e-waste management, the crude recycling, open burning and dumping into landfills of e-waste severely expose people, animal and the environment. Along with economic, political, social, and cultural solutions to the e-waste global problem, the scientific approach based on risk analysis encompassing risk assessment, risk management and risk communication can foster a technical support to resist transgenerational e-waste exposure and health inequalities. This paper presents the latest public health strategies based on the use of integrated human and animal biomonitoring and appropriate biomarkers to assess and manage the risk of e-waste embracing the One Health approach. Advantages and challenges of integrated biomonitoring are described, along with ad-hoc biomarkers of exposure, effect and susceptibility with special focus on metals and metalloids. Indeed, the safe and sustainable management of novel technologies will benefit of the integration and coordination of human and animal biomonitoring.

Human dietary exposure to metals in the Niger delta region, Nigeria: Health risk assessment.

The contamination profile and the human health risk assessment of various heavy metals (Cd, Cr, Mn, Ni and Pb) in vegetable oils, palm oils, butter and shea butter purchased from the Nigerian market were evaluated. Univariate and multivariate analyses including the principal component analysis (PCA), hierarchical cluster analysis (HCA) and heat map visualization were used to evaluate correlation, similarity and source of metals. Dietary intake and dermal absorption through the application in skin were also assessed. The heavy metals 5th and 95th percentile interval range (in mg/kg) were 0.003-0.208, 0.003-0.392, 0.003-1.344, 0.003-0.369 and 0.006-0.531 for Cd, Cr, Mn, Ni and Pb, respectively. Concentrations of Cr and Mn were significantly different across sample categories, being the levels of Mn and Ni positively correlated in both oil and butter samples. The result of PCA, HCA and heat map revealed the profile of heavy metals in oils was different from that of butters, with Pb mainly associated to oils, and Cd, Cr, Mn and Ni to butters. In some samples, the international maximum levels for Cd, Ni and Pb in edible oils were exceeded. Cadmium and Pb dietary intake through Nigerian oils and butters should not be considered negligible for human health protection.

Arsenic and toxic metals in meat and fish consumed in Niger delta, Nigeria: Employing the margin of exposure approach in human health risk assessment.

This study provides information on the health risk of As, Cd, Hg, Pb and V exposure from Nigerian foods consumption (fish, cow, goat and chicken meat) in different age-groups (children, adolescent, adult, senior) and six areas of Niger Delta, Nigeria (Choba, Khana, Eleme, TransAmadi, Uyo, and Yenogoa). The health risk assessment was performed by estimating the weekly or monthly intake of metals from foods and Margin of Exposure (MOE) approach by using established benchmark dose levels (BMDLs). Regarding As, cow and chicken meat products contributed to As exposure intake especially in children resulting in values higher than BMDL0.1 for cancer risk in TransAmadi and Uyo areas. Cadmium exposure was due to cow, chicken and goat meat ingestion mostly in adolescent above the tolerable monthly intake limit in TransAmadi and Uyo areas. Concerning Hg and V, the exposure from Nigerian food did not constitute a potential health hazard. Lead exposure in children were above or close to BMDL0.1 for developmental neurotoxicity by ingestion of cow and goat meat in all the Nigerian areas. In adult and senior the Pb dietary exposure were above the BMDL10 providing a low to negligible risk for kidney effects. The potential concern for health effects in Niger Delta population needs further efforts to decrease As, Cd and Pb dietary exposure especially for children and adolescent, who are more vulnerable to adverse life events.

Concentrations of polycyclic aromatic hydrocarbons in samples of soil, feed and food collected in the Niger Delta region, Nigeria: A probabilistic human health risk assessment.

Polycyclic aromatic hydrocarbons (PAHs) are widely distributed compounds with two or more fused aromatic ring, being some of them classified as carcinogenic. In the present study, the concentrations of 16 PAHs and the sum of them (∑PAHs) were determined in samples of food, feed, plant and soil collected in six different heavily polluted areas (Choba, Khana, Trans Amadi, Eleme, Uyo and Yenagoa) of the Niger Delta Region (Nigeria). Principal component analysis (PCA) was then used to identify groups of variables (PAHs) and groups of samples that were the best in rendering the environmental pollution in that Region of Nigeria. In addition, PAHs food consumption and the derived carcinogenic risks were assessed in a probabilistic way. The highest ∑PAHs (mg/kg) were: 16.7 in cow meat, 8.06 in goat meat, 25.4 in chicken meat, 7.72 in fish, 28.70 in fish feed, 15.3 in chicken feed, 8.42 in plant, and 8.80 in soil. In most of the Nigerian areas, cooked cow meat, chicken and chicken feed presented the highest impact regarding PAHs contamination. The highest intake of PAHs was through meat consumption, with a very high and unassumable carcinogenic risk, which is quite above 10-5 for some PAHs, including benzo [a]pyrene. The results of the present survey highlight the importance of reducing PAHs content in food, specially in meat, in the Niger Delta region.

Metal pollution of soil, plants, feed and food in the Niger Delta, Nigeria: Health risk assessment through meat and fish consumption.

This study was aimed at determining mainly the concentrations of As and other metals (Cd, Cu, Hg, Pb, V and Zn) in samples of feed, soil, plants and foods (fish, chicken, goat and cow meat) grown and consumed in six areas of Niger Delta, Nigeria (Choba, Khana, Trans Amadi, Eleme, Uyo and Yenagoa). Principal Component Analysis (PCA) models were used for identifying groups of variables (i.e., elements) based on the loadings and groups of samples (i.e., plants, soil, fish, meet, feed) according to the scores that contributed most to the environmental pollution in each Nigerian area. In Choba and Khana sites, the results showed a cluster of elements like As, Pb, V and Zn, mostly associated with samples of goat and cow meat, as well as soils, and separated from another cluster of metals composed by Cu and Hg with different origin. In Trans Amadi area, a clustering of As, Cd and V was found associated to different types of meat (chicken, goat, and cow) located in the opposite side of Cu and Hg, which correlated to plants and soil. In Eleme, the strongest loadings were obtained for V and Zn associated with soil and meat (goat and cow) samples and separated from As and Cd. Finally, in Uyo and Yenagoa, dominant elements were As, Cu, Pb and Zn, with proximity to cow and goat liver samples, while Cd and V corresponded to a different pollution pattern. Lead intake trough meat and fish consumption for adults and children were much higher than the tolerable limits set by international organizations. The results of this study should allow a better understanding of the complex phenomenon of metal pollution in the feed-to-food chain and human health in Nigeria, which should help to manage a pollution reduction strategy and give priorities of research and monitoring.

A pediatric health risk assessment of children's toys imported from China into Nigeria.

Trade liberalization led to the flooding of the Nigerian markets with ''made in China'' children's toys. Information about metal contamination in toys is vital to ensure the safety of children's product. This is a pediatric health risk assessment of three toxic metals (Pb, Cd and As) in children toys purchased from Nigerian market. Thirty cheap ''made in China'' toys were purchased from stores in Port Harcourt, Nigeria. Three toxic metals (Pb, Cd and As) in the thirty toys samples were determined by absorption spectrophotometry. Pb, Cd and As were present in all the toys at levels below the limits set by EU. The oral and dermal exposure risk assessment showed no significant non-carcinogenic and carcinogen health risks of public health concern. Some ''made in China'' toys imported into Nigeria may not add to the body burden of these metals in children.

Public Health and Paediatric Risk Assessment of Aluminium, Arsenic and Mercury in Infant Formulas Marketed in Nigeria.

OBJECTIVES: Infant formulas are useful alternatives to breast milk in many circumstances but may pose health risks to infants and children due to contamination by potentially toxic metals. This study aimed to determine the aluminium, arsenic and mercury concentrations and carry out an exposure health risk assessment in commonly consumed infant formulas in Nigeria. METHODS: Different brands of both locally manufactured and imported infant formulas were purchased in March 2017 from stores in Port Harcourt, Nigeria. Analysis of metals in the samples was performed by atomic absorption spectrophotometry. The health risk was assessed by comparing estimated daily intake of aluminium, arsenic and mercury with the provisional tolerable daily intake acceptable by the Joint Food and Agricultural Organization/World Health Organization Expert Committee on Food Additives (JECFA). RESULTS: A total of 26 infant formulas were analysed. The levels of arsenic were higher in cereal-based formulas compared to milk-based formulas, but the difference was not significant (P >0.05). The intake levels of aluminium, arsenic and mercury in infant formulas were found to be 8.02-14.2%, 437.1-771% and 23.7-41.8% of the provisional tolerable daily intake JECFA threshold values, respectively. CONCLUSION: Commonly consumed infant formulas in Nigeria may add to the body burden of arsenic in children.

Edible Mushrooms from Niger Delta, Nigeria with Heavy Metal Levels of Public Health Concern: A Human Health Risk Assessment.

BACKGROUND: Mushrooms (US6759049B2, CA2372185A1, DE60108325D1) can be contaminated by heavy metals as described in various patents. OBJECTIVE: This study has determined the potential human health risk associated with the consumption of mushroom in Niger Delta, Nigeria. Concentrations of Pb, Cd, Sn, Cu, Ni, Al and Zn in both wild/cultivated mushroom and background soil/substrate were determined using Atomic Absorption Spectrometer (AAS). METHODS: Heavy metal pollution was calculated using Bio-Concentration Factor (BCF) and Pollution Load Index (PLI) while human health risk assessment employed Estimated Daily Intake (EDI), Target Hazard Quotient (THQ), Hazard Index (HI), Carcinogenic Risk (CR) and Total Cancer Risk (TCR). The mean concentration of metals in mushroom and soil/substrate ranged from 0.021 mg/kg - 29.16 mg/kg and 0.01 mg/kg - 56.11 mg/kg. When compared with standards by WHO, EU, SON, DPR, USEPA and NAFDAC, 100% violation was observed in Ni, Cu, Cd, Zn and partial violation by Pb in the mushroom sample although soil heavy metal concentrations were within safe limits. RESULTS: There was bioconcentration and heavy metal enrichment as PLI ranged from 3.39 - 23.58. Estimated daily intakes were (0.00 - 0.47, 0.00 - 0.51 and 0.00 - 1.17) mg/kg/day and THQ were (0.01 - 0.46, 0.01 - 0.31 and 0.03 - 1.51) for adults, adolescents and children respectively. There was a violation of Permissible Tolerable Daily Intakes (PTDI) set by JECFA. Hazard indices were all >1, another indication of health concern. CONCLUSION: Nickel showed the highest carcinogenic risk with values of 4.83E-04 - 1.43E-01, 5.31E-04 - 1.00E-01 and 1.20E-03 - 2.29E-01 for adults, adolescents and children respectively. About 80% of TCR ranged from x10-1 - x10-3. Consumption of mushroom in Niger delta-Nigeria may pose significant health risk.

Human health risk assessment of heavy metals in cosmetics in Nigeria.

Forty two different cosmetics were purchased from supermarkets and cosmetic shops within Unitsha Main Market and Eke-Awka markets in Anambra, Nigeria. Of the cosmetics, 16% were locally manufactured in Nigeria while 83.33% were imported into Nigeria. The cosmetics were ashed before digestion and filtration. The filtrates were assayed for lead, cadmium, manganese, nickel, chromium, mercury, and arsenic with atomic absorption spectrophotometry at 205 Å. The health risk assessment methods developed by the United States Environmental Protection Agency were employed to explore the potential human health risk of heavy metals in cosmetics. About 61.91% of the cosmetic samples contained lead with concentration in the range of 0.10-42.12 mg/kg. Cadmium levels of the cosmetics ranged from 0.01 to 1.32 mg/kg, manganese from 0.02 to 67.65 mg/kg, nickel from 0.05 to 17.34 mg/kg, chromium from 0.11 to 9.81 mg/kg, mercury from 0.003 to 0.07 mg/kg, and arsenic from 0.002 to 0.005 mg/kg. Although the target hazard quotients and the hazard indices suggest a measure of safety, cosmetics may add to the body burden of potential toxic metals after chronic exposure.