Applying multivariate analysis to characterize waragi spirits from Acoli, Uganda, by their metal contents

Health and ecological risk assessment of potentially toxic metals in road dust at Lalibela and Sekota towns, Ethiopia

The ecological and health problems resulted from heavy metals (Mn, Fe, Ni, Co, Cu, Zn, Cd, Hg, Pb, As, and Cr) in the road dust in the towns of Sekota and Lalibela, Ethiopia were assessed. The average heavy metal concentrations were ranged from 0.088 (Cd) to 2.714 (Fe) mg/kg. Individual metal and cumulative metals pollution levels in both towns revealed that Lalibela is moderately polluted by Zn, Pb, and Ni and Sekota being moderately polluted by Zn, Pb, Ni, As, Hg, and Cu. Furthermore, the United States Environmental Protection Agency's health risk evaluation model showed that the total heavy metal health risk levels in the road dust ranged from 5.71 × 10^-3 (adult) to 2.57 × 10^-2 (children), with an average risk of 7.35 × 10^-2. Lalibela was found to have higher chance of risk than Sekota. The total lifetime cancer risk varied from 4.51 × 10^-9 (for adults, Sekota) to 7.75 × 10^-9 (for children, Lalibela), with a mean risk of 6.12 × 10^-9 implying a low chance of getting cancer. The hazard quotient and hazard index of all the metals were below the limit. In general, children were found to be more susceptible than adults.

Reference Values on Children's Hair for 28 Elements (Heavy Metals and Essential Elements) Based on a Pilot Study in a Representative Non-Contaminated Local Area

Studies have been published, and laboratories offer services of measuring elements in hair as biomarkers of environmental exposure and/or control of essential elements (trace or macro). These reported values can have only sense if compared with adopted reference values. In this work, we propose provisional reference values based on a pilot child population. The concentrations of 28 elements were measured in children's hair samples. An observational, descriptive, cross-sectional study was conducted in a typical child population in the Mediterranean region void of excessive pollution problems to analyze 419 hair samples of children aged 3-12 years. Children were selected by a simple random method from eight primary education schools in different municipal districts, which included urban, rural and industrial areas. Samples of around 100 mg were washed and acid digested by an optimized procedure. All measures were performed using ICP-MS with Sc, Y and Re as internal standards. The statistical analysis was performed by two approaches: (a) considering all the data and (b) without outliers (second-order atypical data) to compare them with other published studies. The distribution curves in all the elements studied were asymmetric and did not fit the theoretical normality distributions. Therefore, the analysis based on percentiles was more appropriate. In most elements, only slight differences were observed with sex or age, which did not justify proposing separate reference ranges. From the results of this study, provisional reference values are proposed following two criteria: (a) simple application of the table of percentiles built by removing outlier values and (b) values after a detailed analysis case-by-case, considering other data as the distribution profile and other published data of each element. Although the pilot sample was from a limited area, it was carefully selected to be representative of a general non-contaminated population. With this limitation, the proposed reference values might be useful for researchers and physicians until a wider geographical study is available for a large number of elements.

Multivariate analysis of heavy metals content of beef from Soroti, Uganda

Information about food hygiene and quality in the sub-Saharan African countries remains scarce at a time when many of their citizenry are beginning to acquire the much coveted middle income status. Confounding this are challenges linked to monitoring on a continuous basis the safety of food produced by such lucrative industries as the beef industry. The objective of the current study was to initiate a process of encouraging changes in the status quo, by showing how a first step in that direction might look like. Using heavy metal contents of representative beef samples from butcheries in Soroti, Uganda, typical of a sub-Saharan country, we demonstrate how relationships and common sources of metals in food could be identified in a multivariate space. Beef samples from 40 sites were analyzed by atomic absorption spectrometry for iron (Fe), zinc (Zn), nickel (Ni), chromium (Cr), lead (Pb), copper (Cu), cobalt (Co) and cadmium (Cd). The study showed that all beef samples contained these metals, the extent of which were in the order: Fe > Zn >> Ni, Cr > Pb > Cu, Co > Cd. By correlation analysis, the pairs Ni and Cr, Cd and Co, Ni and Fe or Cr and Fe were found to be most likely coming from similar sources. At least three distinct characteristics of beef consumed in Soroti were also found, a distinction perhaps arising from three major categories of feedlots used to raise donor cattle. The incremental risk of children or adults developing cancer over a lifetime was estimated and found to fall into three categories, two of which are separately explained by the presence of Cr or Ni. The sources of these metals remain a matter of speculation on our part. More studies are needed to determine these sources and to understand the nature of cancer risk in the three categories of beef identified here.

Descriptive Analysis of Heavy Metals Content of Beef From Eastern Uganda and Their Safety for Public Consumption

In this study, we initiated an effort to generate information about beef safety in Uganda. Our entry point was to assess by atomic absorption spectrophotometry the levels of essential elements copper (Cu), cobalt (Co), iron (Fe) and zinc (Zn), and non-essential elements lead (Pb), chromium (Cr), nickel (Ni), and cadmium (Cd) in 40 beef samples collected from within and around Soroti (Uganda). The information was used to evaluate the safety of consuming such beef against the World Health Organization (WHO) limits. The latter was accomplished by (i) estimating the daily intake (EDI) of each metal in the study area, (ii) modeling the non-cancer health risk using the target hazard quotient (THQ) and (iii) modeling the cancer risk using the incremental lifetime cancer risk (ILCR). The study finds that the mean concentrations (±95% CI) and EDI were in the order of Fe > Zn > Cr > Ni > Pb > Co > Cu > Cd. Cancer risk was found to be due to Ni > Cr > Cd > Pb and significantly higher in children than adults. The latter particularly demonstrates the importance of Ni poisoning in the study area. Overall, while essential elements in our beef samples were below WHO limits (hence no health risks), non-essential elements had high health and cancer risks due to higher levels of Cr and Ni.

An analysis of heavy metals contamination and estimating the daily intakes of vegetables from Uganda

Background:

Environmental contamination with elevated levels of copper (Cu), cobalt (Co), iron (Fe), zinc (Zn), lead (Pb), chromium (Cr6+), cadmium (Cd), and nickel (Ni)—all states of which are found in Uganda—raises health risk to the public. Pb, Cr6+, Cd, and Ni for instance are generally considered nonessential to cellular functions, notwithstanding the importance of the oxidative state of the metals in bioavailability. As such, we aimed in this study (i) to evaluate heavy metal concentrations in four vegetables from a typical open-air market in Uganda, (ii) to assess the safety of consuming these vegetables against the World Health Organization (WHO) recommended limits of heavy metals consumption, and (iii) to formulate a model of estimated daily intake (EDI) among consumers in the country.

Methods:

This was a cross-sectional study conducted in five georeferenced markets of Bushenyi district in January 2020. Amaranthus, cabbages, scarlet eggplants, and tomatoes were collected from open markets, processed, and analyzed by atomic absorption spectrometry. Modeled EDI, principal component (PCA) and cluster analysis (CA) were conducted to identify relationships in the samples.

Results:

The levels of essential elements in the four vegetables were found to fall from Co > Cu > Fe > Zn. Those of non-essential metals were significantly higher and followed the pattern Cd > Cr > Pb > Ni. The highest EDI values were those of Cu in scarlet eggplants, Zn in amaranthus, Fe in amaranthus, Co in amaranthus, Pb in cabbages, total Cr in scarlet eggplant, Cd in cabbages and tomatoes, and Ni in cabbages. In comparison to international limits, EDIs for Zn, Cu, Co and Fe were low while Ni in cabbages were high. PCA showed high variations in scarlet eggplant and amaranthus. The study vegetables were found to be related with each other, not according to the location of the markets from where they were obtained, but according to their species by CA.

Conclusion:

The presence of non-essential elements above WHO limits raises policy challenges for the consumption and marketing of vegetables in the study area. Furthermore, low EDIs of essential elements in the vegetables create demand for nutritious foods to promote healthy communities.

Effects of solutes on the alcohol-stimulative taste of vodkas

Quantitative analyses of chemical components and sensory tests were carried out on vodka samples to test for stimulative taste of ethanol. Proton nuclear magnetic resonance (¹H NMR) spectra of the vodkas were measured with 600 MHz NMR. The effects of salts on the alcohol-stimulative taste were investigated for 15% (v/v) EtOH-H₂O solution. ¹H NMR spectroscopy results showed that a magnesium salt could reduce the stimulative taste of ethanol organoleptically and, at the same time, strengthen the hydrogen-bonding structure of water-ethanol, although the effect of the magnesium could not be clarified quantitatively in the products of vodka. It was also suggested that a change in the water-ethanol hydrogen-bonding structure could lead to a reduction in the stimulative taste of ethanol in vodka.