Teratogens organic solvents

Since the concern of this monograph is teratogens, the effects of chemicals on sperm and male reproduction are not dealt with. However, for readers interested in the latter a recent review article by Schrag and Dixon, "Occupational Exposures Associated with Male Reproductive Dysfunction" (ref. 20)is recommended. Chapters on various aspects of male reproductive toxicology and on sperm production of men working under heavy-metal or organic-solvent exposure are presented by Hemminki et al. (ref. 19). 

Some single organic solvents, for example, toluene, xylene, and ethanol, are known teratogens. Regretfully, many of the studies in the literature lump all organic solvent exposures together and fail to identify the specific... 

One study that overcomes some of the shortcomings of those just cited reported adverse neurodevelopment outcomes following maternal exposures to 19 organic solvents and mixtures of these. 13 In this study, the women were occupationally exposed to the chemicals listed in Table 24.3. Also included in this table are the K, values and whether or not the specific chemical is a known teratogen or a known endocrine disruptor. 5 It is interesting to note that only three of the chemicals in the study—ethanol, trichloroethylene, and mineral spirits (a mixture of hydrocarbon solvents)—are endocrine disruptors. This shows that teratogenic effects can be induced by chemicals and mixtures that are independent of the endocrine system. 

Paternal occupational exposure to organic solvents can also produce teratogenic effects. Painters, automobile body shop workers, printers, and fiberglass workers have all been shown to father children with low birth... 

Table 24.3 Organic Solvents Reported to Produce Teratogenic Effects1131 and Their K

Ungvary G. 1985. The possible contribution of industrial chemicals (organic solvents) to the incidence of congenital defects caused by teratogenic drugs and consumer goods An experimental study. In Marois M, ed. Prevention of physical and mental congenital defects. PartB ... 

Avoidance of the use of toxic, carcinogenic, mutagenic, or teratogenic organic solvents... 

Ethyl glycol acetate [111-15-9] (2-ethoxyethyl acetate) is a colorless, neutral liquid that is partially miscible with water and readily miscible with organic solvents. It has a slight odor. Ethyl glycol acetate dissolves many natural and synthetic resins. Cellulose acetate is swollen. Poly(vinyl chloride), rubber, and polyisobutene are insoluble. It is no longer used in paints due to its teratogenic properties. 

Methoxypropyl acetate [108-65-6] and 2-methoxypropyl acetate are pleasantly smelling liquids that are partially soluble in water, and miscible with organic solvents. Their dissolution properties and evaporation behavior are comparable but not identical to those of ethyl glycol acetate. 1-Methoxypropyl acetate is less toxic than methyl and ethyl glycol acetates 2-methoxypropyl acetate is teratogenic. 

Methyl glycol [109-86-4] (2-methoxyethanol, ethylene glycol monomethyl ether) has a slight odor, and is miscible with water and organic solvents except aliphatic hydrocarbons. It is a very good solvent for many natural and synthetic resins. It does not dissolve fats, oils (except castor oil), damar resin, rubber, bitumen, hydrocarbon resins, polystyrene, poly(vinyl chloride), and vinyl chloride copolymers. On account of its teratogenic properties it is replaced as a solvent in the paint and colorants sector by other solvents or solvent mixtures. 

Many organic solvents are teratogenic and embryotoxic in laboratory animals depending on the specific solvent, dose, route of administration and particular animal species. The various malformations described include hydrocephaly, exencephaly, skeletal defects, cardiovascular abnormalities and blood changes. Also, some studies suggest poor fetal development and neurodevelopmental deficits. In a portion of these studies exposure levels were high enough to induce maternal toxicity. 

Table 20.3.1. Studies of teratogenicity of organic solvents meeting criteria for meta-analysis [Adapted, by permission, from K.I. McMartin, M. Chu, E. Kopecky, T.R. Einarson and G. Koren, Am. J. Ind. Med., 34,288 (1998) Copyright 1998 John Wiley Sons, Inc. Reprinted by permission of Wiley-Liss, Inc. a division of John Wiley Sons, Inc.]...

Some retinoids are very irritating to the skin, and some are highly teratogenic. Hence when large amounts of retinoids are handled, adequate care should be taken so that neither solid particles nor solutions come into contact with the body. Because retinoids are lipid soluble, organic solvents are used to dissolve them. If a solution of retinoid falls on the body, the solvent quickly evaporates, and the retinoid is absorbed by the skin. Therefore, it is recommended that gloves be worn while working with retinoids. 

The primary risk of utilizing flammable substances is the specific risk of fire, which is, of course, a severe threat to both property and personnel. In addition, many flammable chemicals do in fact have associated health risks that are independent of their flammable properties for example, many organic solvents are quite toxic, while some are also carcinogens, mutagens, or teratogens as well. However, since the fire hazard is usually the... 

A study in the Netherlands reported congenital malformations in the offspring of male painters with occupational exposure to organic solvents [16]. Specific teratogens were not identified, but as has been previously discussed in Sections 12.5 and 13.5, both waterborne paints and oil-based paints contain mixtures of lipophilic and hydrophilic species. Exposures to both types of paints have been associated with low-level unexpected effects. Accordingly, the teratogenic results reported in the Dutch study are not surprising. 

Table 19.2.1. Studies of teratogenicity of organic solvents meeting criteria for meta-anaiysis.

---