Organic contaminants - Indoor Environmental Quality - page 93

H
-C=O

|

in their chemical structure. The carbonyl is in a terminal position in alde-
hydes. A compound is described as an aldehyde if it has one terminal car-
bonyl, a dialdehyde if it has two, and a trialdehyde if it has three carbonyls.
Aldehydes include saturated (single bonds) aliphatic, unsaturated (one
or more double bonds) aliphatic, and aromatic or cyclic compounds. Satu-
rated aliphatic aldehydes include formaldehyde (one carbon), acetalalde-
hyde (two carbons), propionaldehyde (three carbons), butryaldehyde (four
carbons), valeraldehyde, glutaraldehyde, etc. As can be seen in Table 4.1 ,
glutaraldehyde is a dialdehyde with carbonyls on both ends of the molecule.
Unsaturated aliphatic aldehydes contain a carbon-carbon double bond
( Table 4.1 ) . They include acrolein (acryaldehyde), methacrolein, and cro-
tonaldehyde. Methacrolein is commonly used to produce methyl methacry-
late, an eye-irritating ester used as an adhesive in many industrial applica-
tions. Aromatic aldehydes include compounds such as benzaldehyde and
cinnamaldehyde.

Table 4.1 Chemical Structures and Properties of Common Aldehydes

Solubility
(g/L)

Compound Structure M. W.

O

Formaldehyde 30.03 560

H C H

O

Acetaldehyde 44.05 200

CH 3 C H

Glutaraldehyde 100.12 Miscible

O

Acrolein 56.06 210

CH 2 CH C H

O

Crotonaldehyde 76.09 181

H

CH 3 CH CH C

Benzaldehyde 106.11 3

Source: From Leikauf, G.D., in Environmental Toxicants: Human Exposures and

their Health Effects Van Nostrand Reinhold (John Wiley &

Sons), New York, 1992, chap. 2. With permission.

, Lippman, M., Ed. ,