The human body uses oils and fats in the diet as an energy source, as a structural component and to make powerful biological regulators. The significance of trace metals and toxicological effects of heavy metals on human health and nutrition have been increasingly studied in recent years. Micronutrients play a role in cellular defences, acting both as 'sinks' for free radicals or by being involved in the activity of the enzymes required to deal with the oxidative products e.g. zinc and copper in superoxide dismutase. Presence of metals in edible oil could be from soil or during the manufacturing process. In this present study, the levels of some metals were determined in vegetable oils sold in Zaria, Nigeria. The concentration ranged from 19.

No abstract

Objectives: Dareta village in Zamfara state of Nigeria is one of the villages plagued with the lead (Pb) poisoning crisis of 2010. Dareta and neighboring villages were remediated by simple excavation of topsoil rich in Pb, and burying same in landfills. This study was embarked to assess the physicochemical parameters of some sources of water supply and possible health impacts on humans. Material and Methods: The village was imaginarily mapped into three sites; Residential Homes (Site 1), Markets and Village Squares (Site 2), and Farms with Irrigation Facilities (Site 3). From the three sites, a total of 30 water samples (10 shallow wells, 10 boreholes, and 10 stream/surface water) were randomly collected, according to availability. The physical parameters (Temperature, Conductivity, and Total Dissolved Solids [TDS]) were assessed in situ using a conductivity/TDS meter (model 44600.00, HACH, USA), the assessment of pH was also carried out in situ using an electronic pH meter, (pH 210 micro-processor, Hanna Instrument, USA). The evaluation of heavy metals concentration (Pb, cadmium [Cd], chromium [Cr], and manganese) was done using an Atomic Absorption Spectrophotometer (modelAA-6800, Schemadzu, Japan). Results: In groundwater (boreholes and wells), the mean temperature and conductivity were higher than the World Health Organization (WHO) safety levels for “drinking water,” while those of TDS and pH were within the limits. In surface water (streams), the assessed physical parameters were not higher than the WHO safety limits, while the concentrations of Pb, Cd, and Cr were above the drinking water guidelines. The risk implication in the human populations consuming the water was determined using the estimated average daily intake (EADI) and the target hazard quotient (THQ). The EADI for Pb, Cd, and Cr for all the water sources in both adult and children consumer populations exceeded the reference dose by US-EPA. The THQ for Pb, Cd, and Cr in both adult and children consumer populations were >1. Conclusion: These findings portend toxicity and increased hazards for the human populations that source their drinking water from the borehole, well, and stream in this village.

Solid waste dump where leachate generated is allowed to escape to the surrounding and underlying water body is a major threat to borehole water. This study was designed to assess the impact of solid waste dumps on ground water quality and the current status of the quality of borehole water in Calabar municipality. Randomly selected boreholes around Lemna road where the final dump site of solid waste in Calabar is located, Etta Agbor area where there are no major dumpsites but a few sporadic dumps and Satellite town where there are relatively no dumpsites were thoroughly examined. Physicochemical properties of water quality were determined following standard analytical procedure and metal content by atomic absorption Spectrophotometry using Shimadzu atomic absorption spectrophotometer (model AA6800, Japan). Metal content and other physicochemical parameters generally displayed the trend Lemna road > Etta Agbor road > Satellite town. The differences were found to be statistically significant (ANOVA, p < 0.05), suggesting that solid waste dumpsites have reasonable influence on the quality of ground water in Calabar municipality. A significant (p < 0.01) positive correlation was observed between each of the metals and between the metals and most of the physicochemical parameters, suggesting that a similar source is responsible for their presence at the concentration determined. When ompared with WHO drinking water standards, borehole water in the study area especially Lemna road was seriously implicated. The study thus concludes that solid waste dumps in Calabar municipality have significant influence on the quality of ground water and that continuous use of borehole water from the study area for drinking or other domestic purposes without any form of physical or chemical treatment could pose serious toxicological risk. It was therefore recommended that ground water in Calabar municipality should be put under surveillance in other to protect it from further degradation and safeguard public health.