Peer-reviewed article CONSUMER SAFETY & ANALYTICAL METHODS Andrew D. Hardy The chemical composition of traditional eye cosmetics in Sudan ANDREW D. HARDY1*, PETER BARSS2, GAVYN ROLLINSON3, RAGINI VAISHNAV4 *Corresponding author 1. University of Exeter, Centre for Medical History, College of Humanities. Exeter, EX4 4RJ, Devon, United Kingdom 2. United Arab Emirates University, Department of Community Medicine, Faculty of Medicine and Health Sciences Box 17666, Al Ain, United Arab Emirates 3. University of Exeter in Cornwall, Camborne School of Mines, College of Engineering, Mathematics and Physical Sciences Tremough Campus, Penryn, TR10 9EZ, Cornwall, United Kingdom 4. Sultan Qaboos University, College of Medicine, Box 35, Al-Khod 123, Sultanate of Oman child not look attractive). Specifically in Sudan, adult females ABSTRACT: This study was undertaken in order to use kohl to outline the upper and lower lids of their eyes, a determine the chemical composition of traditional eye bridegroom may have kohl applied to his eyes for the cosmetics (“kohls”) available in Sudan. A total of 21 kohl wedding ceremony and the same is often done to tiny/new- samples were purchased in local markets (“souks”). The born babies in the early weeks of life. Also, (black) kohl is used techniques of X-ray powder diffraction (XRPD) and low for staining tattoos and facial scars black. vacuum scanning electron microscopy (LVSEM) were To our current knowledge this study is the first to chemically used to analyse the samples. Overall, for the 21 samples, analyse modern-day traditional eye cosmetics available in Sudan. it was found that 7 (33 percent) contained a lead compound (galena, PbS) as the main component; with a further 1 sample having it present as a minor MATERIALS AND METHODS component. The other main components were found to be one of the following: amorphous carbon/a carbon- In both traditional and modern markets (“souks”), at nine based compound (6/1), iron compounds (goethite, locations, a total of 24 samples were purchased. These nine FeO(OH) and hematite, Fe2O3 mixtures) (3), calcite/ locations were: Al Ubayyid, Bahri, Kassala, Khartoum, Malakal, aragonite (CaCO3) (1/1), zincite (ZnO) (1) and halite Omduran, Port Sudan/Said , Wadi Halfa and Wadi Madani. (NaCl) (1). Eight of them are shown on the map of Sudan (Figure 1). The one location not shown, Bahri, is in fact a few kms. NE of Khartoum. INTRODUCTION As part of our continuing study of traditional eye cosmetics (kohls) we have looked at the chemical composition of such cosmetics available in Sudan; with especial reference to determining the percentage of the samples purchased that contain a lead compound. For useful background information on traditional eye cosmetics in general, and on our previously studied ones in particular, the reader is referred to our previous publications on the kohls of Egypt (1-3), Oman (4), the United Arab Emirates (UAE) (5, 6), Qatar and Yemen (7), Morocco (8) and most recently Syria (9). Some recent relevant mentions of traditional eye cosmetics in the published literature are the elemental analyses of some kohl samples seized in France (10) - where most of the samples (14 of 18) contained lead, an analysis of a single lead-containing eyeliner and a study of its negative effects on rat liver and brain (11), and a study of elevated blood lead levels in children in India where surma (an Indian name for traditional eye cosmetics) use was found to be a predictor of such elevated lead levels (12). Traditional eyeliner (i.e. kohl) is in general used for a variety of reasons: to make the eyes beautiful (e.g. to make the eyes appear larger); as an eye medicine for a variety of complaints (actual and as a preventive); as a daily tradition from both Figure 1. A map of Sudan before the indipendence of South Sudan cultural and religious backgrounds; and as a preventive for on July 9th, 2011. children against the “evil eye”/“the evil one” (i.e. making the 38 Household and Personal Care TODAY - n3/2011 CONSUMER SAFETY & ANALYTICAL METHODS On later inspection, two of these 24 samples were found to be with zincite (ZnO) and halite (NaCl) being the major medicines and were not in fact used as traditional eye components of the remaining 2 samples. Figure 3 shows the cosmetics. Also, two labelled samples (made in Saudi Arabia), distribution of the main element of the major component in all purchased in two different locations, were found to be the kohl samples studied. identical and so only one was included in those to be fully chemically characterised. These 21 samples are regarded as being representative of the kohl samples readily available in the various souks of Sudan. Of the 21 samples, 10 were made in Sudan and the other 11 were made abroad (6 in Saudi Arabia, 4 in India and 1 in Pakistan). Most (15) of the samples were black/grey-black/silvery-grey in colour; with 3 being various shades of red, 2 white/grey-white and 1 yellow. The price per kohl sample was between 2 and 14.5 SNP (Sudan New Pound), where 1 SNP was equivalent to 0.49 US$. A selection (5) of some of the kohl samples purchased are shown in Figure 2. Figure 3. Distribution of the main element of the major component in the Sudan kohl samples. A total of 6 samples were coloured (i.e. not black/grey-black/ silvery-grey). For the 3 shades-of-red samples the colourant was a mixture of iron compounds (goethite and hematite) and for the grey-white (1) and white (1) samples the colour was given by the presence of aragonite and halite. The one remaining coloured sample was yellow, where its colour arises from one or more of the currently unknown amorphous Figure 2. A selection (5) of the kohls purchased in Sudan. organic (i.e. carbon-based) major component(s). The sample has been tentatively identified as “Gum Arabic” and it is assumed that it is burnt to give amorphous carbon --- for The 21 kohl samples were examined by the analytical making a black kohl. For the 15 samples that were black/grey- techniques of x-ray powder diffraction (XRPD) and low black/silvery-grey their colour was usually given by their major vacuum scanning electron microscopy (LVSEM) (with the latter components - that is amorphous carbon (6) and galena (7). technique having an energy dispersive x-ray (EDX) However, for two samples their colour - black - was given by a microanalyser attached). The latter technique was used to minor component. For one sample (based on zincite) the give quantitative elemental analysis for atomic number of 6 (black) minor components were amorphous carbon and (i.e. carbon) and above; whilst the former technique was used magnetite (Fe2O3); and for the other sample (based on to identify crystalline compounds present and to give (semi- calcite) it was graphite. quantitatively) their percentages. DISCUSSION RESULTS Toxicology of lead For the 21 kohl samples purchased it was found that 7 had As has been stated before by us in our previous publications galena (PbS) present as the main component, with a further 1 (1-9), lead compounds are toxic by ingestion, inhalation and by sample having it present as a minor component. Two of the 7 skin exposure. Children are more susceptible than adults to lead (galena-based) samples were matt in texture, and 4 of the poisoning as adults absorb 5-15 percent of ingested lead while remaining 5 samples are described (by us) as “shiny”, with the children can absorb as much as 41 percent. The toxic effects of remaining sample being described as “very shiny”. The lead form a continuum from clinical or overt effects to more meaning/importance of the texture of a galena-based subtle ones (13). The critical effects in infants and children sample is mentioned in the later Toxicology (sub)section. The involve the nervous system. Values in children, of their blood colours of these 7 samples varied between black (1), grey- lead levels (BLLs), that are greater than 10 µg/dl are now black (5) and silvery-grey (1). Also, six samples were based on considered abnormal (14, 15), and it has been shown that amorphous carbon and one was based on one or more significant intellectual impairment occurs in young children who unknown amorphous compound(s) - which were assumed to have blood lead levels below 10 µg/dl (16, 17). be carbon-based; and three samples were based on iron In a previous publication (1) we discussed galena’s (lead sulfide, compounds (being mixtures of goethite (FeO(OH)) and PbS) particle size with respect to the associated kohl powder hematite (Fe2O3)). One of the latter samples contained being “shiny” or “matt” in texture and with respect to its rate of galena as a minor component (at approx. 21 percent). dissolution in gastric fluid. It was found by us that at a mean Additionally, two samples had calcium carbonate as the particle size for galena of about 10 µm the kohl powder (with major component (once as calcite and once as aragonite); galena as the major component) became totally matt in Household and Personal Care TODAY - n 3/2011 39 CONSUMER SAFETY & ANALYTICAL METHODS texture. Above this particle size the sample becomes percent). Thus the first of these two samples could probably increasingly “shiny”. It had previously been found (18) that cause lead toxicity if ingested by a child, and the second reducing the particle size of galena leads to a significant sample could possibly cause such toxicity. increase in its rate of dissolution in gastric fluid. Thus a matt For the sample made in India (“Hind Ka Noor Eyeliner”, and galena-based powder would be much more easily dissolved in black in colour) the medicinal information given on the gastric fluid than a “shiny”/“very shiny” powder; with the latter enclosed leaflet stated: “Protects you permanently from perhaps going straight through the body with minimum diseases of the eye” and “Very advantageous against the absorption and negligible toxicity.