Page 353 - Industrial Ventilation Design Guidebook

5,3 TOX1C1TY AND RISKS INDUCED BY OCCUPATIONAL EXPOSURE TO CHEMICAL COMPOUNDS 309
TABLE 5. i 9 Common Cross-Reacting Chemicals

Chemical Cross- Reactor

Abietic acid Pine resin (colophony)
Balsam of Peru Pine resin, cinnamates, benzoates
Bisphenol A Diethylstilbestrol, hydroquinone monobenzyi ether
Canaga oil Benzyl saiicylate
Chlorocresol Chloroxylenol
Diazolidinyl urea Imidazolidinyl urea, formaldehyde
Ethylenediamine di-HCl Arninophylline, piperazine
Formaldehyde Arylsulfonamide resin, chloroallyl-hexaminiurn chloride
Hydroquinone Resorcinol
Methyl hydroxybenzoate Parabens, hydroquinone monobenzyi ether
p-Aminobenzoic acid p-Aminosalicylic acid, sulfonamide
Phenylenediamine Parabens, p-aminobenzoic acid
Propyl hydroxybenzoate Hydroquinone monobenzyi ether
Phenol Resorcinol, cresols, hydroquinone
Tetramethylthiuram disulfide Tetraethylthiuram mono- and disulfide
Source: Modified from Rice and Cohen. 161

treat. Chloracne is characterized by hyperplasia of the epithelial cells of the seba-
ceous glands associated with inflammatory skin changes typical of acne. 164
TCDD is the most potent inducer of chloracne. This has been well known
since the accident in Seveso, Italy, in 1976 in which large amounts of TCDD
were distributed in the environment subsequent to an explosion in a factory
that produced a chlorophenoxy herbicide, 2,4,5-T. TCDD is an impurity pro-
duced during the production of 2,4,5-T. The most common long-term effect of
TCDD exposure was chloracne. Exposed individuals also suffered increased
excretion of porphyrins, hyper-pigmentation, central nervous system effects,
and liver damage and increased risk of cancer was a long-term consequence of
the exposure. In addition to TCDD, polychlorinated biphenyls (PCBs), poly-
chlorinated dibenzofurans, and polychloronaphthalens cause chloracne as
51 150 165
well as other effects typical of TCDD. ' '
Allergies
Allergies are diseases in which immune responses to antigens, compounds
which otherwise would be innocuous, cause inflammation. The immune re-
sponse occurs in two stages. First, the person becomes sensitized to an antigen.
He or she will remain asymptomatic until there is a new exposure, which will
provoke an inflammatory response. Hypersensitivity is often used as a syn-
onym for allergy. Allergic disease can be classified according to the immuno-
logic mechanism provoking it. Traditionally, a classification into four types is
used, as first presented by Cell and Coombs. 166
Type I allergies are mediated by immunoglobulin E (IgE). Unlike the other
immunoglobulins (G,M,A, and D), which are part of the essential defense