Safety evaluation of wild apricot oil.

Wild apricot, a variety of Prunus armeniaca, grows in the hilly regions of India. The seeds yield 27% of kernels. The potential availability of the kernels is 40,000 tons/year and these yield 47% of oil. The oil has 94% unsaturated fatty acids, rich in oleic and linoleic acids. Systemic effects and nutritional quality of wild apricot oil (WAO) were assessed in a 13-wk feeding study in weanling albino rats using a diet containing 10% WAO as the sole source of dietary fat. A similar diet containing groundnut oil (GNO) was used as the control. WAO did not manifest any toxic potential. The food consumption, growth rate and food efficiency ratio of rats fed WAO were similar to those fed GNO. The digestibility of this oil was found to be comparable to that of GNO. There were no macroscopic or microscopic lesions in any of the organs that could be ascribed to WAO incorporation in the diet. The results of this study indicate that WAO could be used for edible purposes without any overt toxic signs or symptoms. However a long-term study may be needed to confirm its innocuousness further.

A rapid in vitro method of identifying contact allergens and irritants.

A rapid in vitro method has been developed to screen skin allergens and irritants. It has been shown by others that allergens induce the secretion of interleukin (IL)-1 betaby dendritic cells and macrophages, which are known antigen-presenting cells present in blood, and that irritants induce the secretion of IL-1 alphaby the same cells. We have shown that the allergens nickel, chromium, isoeugenol, and dinitrofluoro benzene induce the secretion of IL-1 betaat levels that are two- to threefold higher than those of controls and that the nonallergens and irritants sodium dodecyl sulfate, Tween-20, acetic acid, sodium hydroxide, and dimethyl sulfoxide fail to induce such a response. All the chemical allergens tested induced the secretion of IL-1 alphaat concentrations two- to fivefold higher than those of controls, depending on the concentration and the particular irritant. Allergen-induced T-cell proliferation has also been demonstrated by the expression of IL-2 as well as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolim bromide reduction (MTT) assay (10-50% more than control). All the allergens and irritants caused cytotoxicity at higher doses, as indicated by the release of lactate dehydrogenase. This method can be used to differentiate the allergens from the irritants in a simple and convenient manner.

Role of different valence states of chromium in the elicitation of allergic contact dermatitis.

Chromium, a known contact sensitizer, is present at high levels in certain detergent bars (40-50 p.p.m.) sold in India. A concern was whether chromium present in such detergent bars could sensitize users or their use lead to the elicitation of allergic contact dermatitis. Chromium present in detergent bars was analyzed for its valence state. It was found to be trivalent [Cr (III)] and not hexavalent [Cr (VI)]. An elicitation test on normal volunteers, as well as on volunteers who were sensitive to chromium, was carried out to determine the elicitation potential of chromium (III) in the bars. Of the 48 volunteers who completed the study, 30 did not show any positive response to either potassium dichromate, the positive control, or the detergent bar containing chromium (III). 18 volunteers who were identified as chromium-sensitive showed a positive response to potassium dichromate but not to the detergent bar containing trivalent chromium. This study clearly showed that the detergent bar with 40-50 p.p.m. of trivalent chromium did not elicit any allergic contact dermatitis even in individuals known to be chromium-sensitive. Hexavalent chromium (potassium dichromate) did however, elicit allergic contact dermatitis in these subjects.