Geranium-like odour

Weapons-grade lewisite consists of lewisite I, (CHC1-CH)AsC12 (90%) and lewisite II, (CHC1-CH)2AsC1 ( 10%), with very small amounts of the non-vesicant lewisite III, (CHCl-CH As (which imparts the characteristic geranium-like odour). Biomedical sample analysis has been directed only at products derived from lewisite I. 

Geranyl acetate (trans-3,7-dimethyl-2,6-octadien-1-yl acetate) Found in many essential oils including geranium, citronella, lavender, petitgrain and sweet marjoram. Fruity, floral, fresh, rose-like odour. 

Citronellyl formate (3,7-dimethyloct-6-en-1-yl formate) Found in geranium oil. Fruity, floral, light rose-like odour. 

Sorbic acid under certain conditions is known to generate at least two types of off-odours - one geranium-like (wine) and the other a paint, plastic, paraffin-note (cheese). 

Crowell, E.A., J.F. Guymon, Wine constituents arising from sorbic acid addiction, and identification of 2-ethoxyhexa-3,5-diene as source of geranium-like off-odour, Amer. J. Viticult., 26, p. 97, 1975. 

The common name in India for this grass is Rosha or Rusa grass and as for many years the oil found its way into Europe vi Constantinople, it was called—and still is to some extent— Turkish geranium oil, as it is an oil rich in geraniol and having an odour something like that of geranium oil. 

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