Regulations (Preambles to Final Rules) - Table of Contents|
| Record Type:||Occupational Exposure to Formaldehyde|
| Title:||Section 3 - III. Properties, Manufacture, and Uses of Formaldehyde|
III. Properties, Manufacture, and Uses of Formaldehyde
The chemical "formaldehyde" is a colorless, pungent gas at room temperature with an approximate odor threshold of about 1 ppm [Ex. 73-120]. While the term "formaldehyde" is also used to describe various mixtures of formaldehyde, water, and alcohol, the term "formalin" more precisely describes aqueous solutions, particularly those containing 37 to 50 percent formaldehyde and 6 to 15 percent alcohol stabilizer. Most formaldehyde enters commerce as formalin. Alcoholic solutions of formaldehyde are available for processes that require low water content [Ex. 73-53]. Paraformaldehyde, a solid, also serves as a source of formaldehyde gas. Formaldehyde gas per se is not available commercially. The Chemical Abstracts Service (CAS) has assigned the number "50-00-0" to formaldehyde. This number applies to both formaldehyde gas and its aqueous or alcohol stabilized solutions.
Formaldehyde is a major industrial chemical, ranked 24th in production volume in the United States [Ex. 138-F]. In 1985, 5.7 billion pounds of 37 percent formaldehyde (by weight) was produced. Formaldehyde has four basic uses: as an intermediate in the production of resins; as an intermediate in the production of industrial chemicals; as a bactericide or fungicide; and as a component in the formulation of end-use consumer items. The manufacture of three types of resins: urea-formaldehyde, phenol-formaldehyde, and melamine formaldehyde, accounts for about 59 percent of total consumption [Exs. 70-2; 73-52]. An additional seven percent is consumed in the production of thermoplastic acetal resins [Ex. 8]. About one-third is used in the synthesis of high volume chemical derivatives, including pentaerythritol, hexamethylenetetramine, and butanediol [Ex. 8]. Two percent is used in textile treating and small amounts of formaldehyde are present as preservatives or bactericides in consumer and industrial products, such as cosmetics, shampoos and glues.
Some products prepared from formaldehyde contain unreacted formaldehyde residues which may be released from the product over its useful life. One example is urea-formaldehyde resin. Urea-formaldehyde resin is a generic name that actually represents an entire class of related formulations. Over 60 percent of urea-formaldehyde resin production in 1977 was consumed by particleboard and plywood manufacturing, where the resin is used as a glue. Urea-formaldehyde resins are also used in decorative laminates, textiles, paper, and foundry sand molds [Ex. 73-53].
Formaldehyde resins are used to treat textiles to impart wrinkle-resistance to clothing. About 60-85 percent of all apparel fabric is finished with formaldehyde-containing resins. As apparel manufacture is the sixth largest industry sector in the United States [Exs. 70-2; 70-14], this use is the major source of widespread exposure to formaldehyde because of the large number of workers potentially exposed.
Formaldehyde destroys bacteria, fungi, molds, and yeast. Its commercial importance as a fungicide is probably its greatest use as a disinfectant [Ex. 70-2]. Because of its bactericidal properties, formaldehyde is used in numerous cosmetic preparations.
Formaldehyde's uses can lead to widespread exposure in downstream industries. For example, when formaldehyde is present in disinfectants, preservatives, and embalming fluid, worker exposure can occur. Although formaldehyde changes into other chemicals when urea-formaldehyde resins and concentrates are produced, decay may occur, causing workers in numerous industries including wood products and apparel manufacture to be exposed to airborne formaldehyde when it offgasses from products manufactured with these resins.
|Regulations (Preambles to Final Rules) - Table of Contents|