Table 1.

Chromogenic organic solvents as reported by Gerarde¹²⁶ from his experimental animal studies using a single subcutaneous injection of the listed substances of unknown purity in a dose of approximately 5 ml/kg. Gerarde reported that treatment of male and female rats and hamsters with 1,2-diethylbenzene (1,2-DEB) or 1,3-diethylbenzene (1,3-DEB), but not 1,4-diethylbenzene (1,4-DEB), caused the excretion of a blue dye in the urine. The sclera, blood, plasma and tissues were stained a deep blue that persisted for many days. Later work using purified compounds found that 1,2-DEB (95%) and DEB mixtures,¹²⁷ but not 1,3-DEB (99%) or 1,4-DEB (96%) alone, were chromogenic in rats given repeated oral doses of 500 and 750 mg/kg/day, 5 days/week for 10 weeks.^46,49 Humans may also excrete colored (green) urine following exposure to tetralin,¹²⁷ and a blue discoloration of the skin and internal organs develops in rodents repeatedly treated with acetylethyltetramethyltetralin.^56,57

Monocyclic	Dicyclic
1,2-Xylene	Indene
1,2-Ethyltoluene	Tetralin
1,2-Diethylbenzene	Diphenyl
1,3-Diethylbenzene	Diphenylmethane
1,2-Diisopropylbenzene	1-Methylnaphthalene
Triethylbenzene (mixture)	2-Methylnaphthalene
Diethyldisopropylbenzene	1-Ethylnaphthalene
Indane	2-Ethylnaphthalene