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

Abstract

Quality control during spirits production and means of authenticating or verifying sources of spirits in the sub-Saharan region of Africa are limited due to lack of resources and the scientific acumen required to develop methodologies for characterizing spirits. However, the increasing needs to protect consumers from negligence, or willful contamination of spirits in this region underscores the urgency with which growth in this area must happen. In this paper, we describe a multivariate statistical framework upon which characterization, identification and authentication of spirits could be developed. The framework exploits the unique chemical fingerprints of spirits with the goal of accomplishing three functions simultaneously: the detection of class differences, the authentication of spirits and the verification of sources. In a test case using the metal contents of 17 Ugandan spirits, this framework shows (i) that a class of unrecorded spirits known locally as Lira-Lira can be singled out from other spirits by their Cu contents, (ii) that localities from where the Lira-Lira spirits were purchased can be resolved to within 8 km by cluster analysis and principal component analysis, (iii) that cluster analysis loadings and scores, placed side-by-side, can pair spirits and their unique discriminating contaminants directly, (iv) that the most important metals for authenticating 13 spirits, source verification and production methods are Al, Sr, Ba, Mn, Zn and Cu (high concentration variability across samples is the qualifying factor), (v) that common sources of contamination can be detected by Pearson correlation analysis (this study finds that Sn/Cd, Pb/Cr, Tl/Cr, Pb/Ni or Cu/Ag as well as the triad Se/As/Ni in the 13 Ugandan spirits are from similar sources), and (vi) that inconsistency in spirits production can be detected with empirical data. Such rudimentary solutions to characterizing spirits have never been offered to the sub-Saharan countries.

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

“…The findings here, preliminary as they may be, when put together with a preponderance of evidence pointing to serious and sustained consumption of contaminated foods in Uganda, 3,82,90,[100][101][102][103][104] justify a policy revisit by the responsible regulatory authorities in Uganda, i.e. National Drug Authority (NDA), Ministry of Health, and Ministry of Agriculture Animal Industry and Fisheries (MAAIF), Uganda National Environmental Authority (NEMA), to promote food safety and trade in vegetables.…”

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

“…The National Environmental Authority of Uganda (NEMA), could devise routine monitoring strategies to ensure that the situation doesn't depreciate further. On a broader scale, this falls squarely into the ecological cycle of pollution in Uganda which has been shown to involve everything from waste management ( 11 , 15 , 16 ), sources of natural water ( 12 – 14 ), effect on aquatic wildlife ( 10 ), state of drinking water ( 5 , 6 ) to production of alcoholic beverages ( 8 , 9 ) as well as food sold to the general public in the streets of Uganda ( 7 ). Similar findings of heavy metals have been reported in Kenya fishes and beef ( 2 , 47 ).…”

“…Contamination of food by heavy metals such as lead (Pb), iron (Fe), chromium (Cr), cadmium (Cd), copper (Cu), cobalt (Co), Nickel (Ni) and zinc (Zn) in developing countries is a major public health problem ( 1 , 2 ). This has been demonstrated in Uganda, for example, in beef ( 3 , 4 ), in drinking water ( 5 , 6 ), street food ( 7 ), alcoholic beverages ( 8 , 9 ), fish ( 10 ), food crops grown at dumpsites ( 11 ), and in food consumed around Lake Victoria and Lake George ( 12 – 14 ). Compounding this is human activities such as mining, irrational usage of chemicals and poor policies on industrial waste management which only exacerbate the problem ( 15 , 16 ).…”

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

“…At this time, Pb, Cd, Co and Ni are 2nd, 7th, 52nd, and 58th on the US Agency for Toxic Substances and Disease Registry priority list of 275 substances that pose the most signi cant potential threat to human health (ATSDR, 2019). It was also likely that where Pb contamination is found in Uganda, there is likely to be Cr contamination as well (Otim et al, 2019a). Of the eight metals studied here, only Pb and Cd appear to be regulated in cattle feed in Uganda (maximum 5.0 mg/kg and 0.5 mg/ kg, respectively (Uganda National Bureau of Standards, 2018).…”