PRINCIPLES OF TOXICOLOGY

16.12 TOXIC PROPERTIES OF REPRESENTATIVE ETHERS 391
Figure 16.17 Ether compounds.
used as an anesthetic at one time, but it is slightly irritating to the skin and contact with the eyes should
be avoided. It produces anesthesia in humans in a concentration range of 3.6–6.5 percent in air, but
respiratory arrest occurs at 7–10 percent, providing only a small margin of safety. Ether can produce
profound muscular relaxation by means of corticospinal and neuromuscular blockade. However,
nausea and vomiting are common subsequent side effects and were limiting factors in its use.
Isopropyl ether (see Figure 16.19) (or diisopropyl ether) is comparatively more toxic than ethyl
ether, and causes irritation at much lower concentrations than those which are required to produce
anesthetic effects. This effectively limits its use as an anesthetic. In humans, 500 ppm for 15 min causes
no irritation, but odor is noticeably unpleasant at 300 ppm. At 800 ppm, disagreeable irritation of the
eyes and nose is noticeable.
Figure 16.18 Ethyl ether.
Figure 16.19 Isopropyl ether.
Other Ethers
The unsaturated ethers are, in general, more toxic than the saturated ethers, produce anesthesia faster,
and possibly cause liver damage. Divinyl ether is more potent than ethyl ether. Halogenated ethers can
cause very severe irritation to the skin, eyes, and lungs. For example, the vapors of chloromethyl ethers
are painful at 100 ppm. The chlorinated ethers may also be potent alkylating agents, and compounds
such as bis(dichloromethyl) ether are classified as carcinogens by some regulatory agencies (see also
Chapter 13). Aromatic ethers, on the other hand, generally are less volatile, less irritating, and less
toxic than the alkyl ethers.
The solvent 1,4-dioxane (or diethylene dioxide) is a member of the glycol ethers and is used in a
wide range of lacquers, paints, dyes, cosmetics, deodorants, stains, and detergent products. It should
be carefully distinguished from the dioxins (e.g., 2,3,7,8-tetrachlorodibenzodioxin; or 2,3,7,8-TCDD)
in any discussions of toxicity and environmental. Liquid dioxane is a painful irritant to the eyes and
skin, and can be absorbed dermally in significant quantities. Renal and hepatic damage may be