Contamination adventitious hydrocarbons

According to the high resolution spectra (Fig. 3), the apparent percentage of the ester species (286.5 eV) appears smaller than that of the carbonyl species (288.6eV) on both DOS-and ATBC-oiled sheets, indicating the contribution of the contamination by adventitious hydrocarbon species. The measured percentage of the carbonyl carbon of as-received sheets is 10.9 % for DOS and 18.0 % for ATBC, those of which roughly correspond to the calculated ratios of DOS (9.2 %) and ATBC (21.0 %), respectively. But the effect of contamination makes it difficult to have further insight into the deviation from the calculated values. 

Table 1 Top Binding energy of common elements in chemical functions of solids, referred to the C—(C, H) component of the C Is peak of aliphatic hydrocarbon or adventitious contamination set at 284.8 eV, Ref. unless otherwise specified. Bottom-. Repeat unit of the polymers listed...

Other examples of food additives which in effect represent adventitious contamination include the polynuclear hydrocarbons which are found in smokes 1 4 dioxan (a carcinogen) in polysorbates free amines in dyestuffs chlorohydrins, including epichlorhydrin, in modified starches and o-toluenesulphonamide in saccharin. Attention is also being paid to problems arising from the hypersensitivity of some individuals to food components and to food additives such as tartrazine. 

---