Acrylic Acid 45
Acrylates
See Acrylic Acid; Ethyl Acrylate; Methyl Acrylate.
Acrylic Acid Sanjay Chanda and Harihara M Mehendale & 2005 Elsevier Inc. All rights reserved.
products, detergents, and waste water treatment chemicals.
Exposure Routes and Pathways *
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CHEMICAL ABSTRACTS SERVICE REGISTRY NUMBER: CAS 79-10-7 SYNONYMS: Acroleic acid; Ethylenecarboxylic acid; Propene acid; Propenoic acid; Vinylformic acid; 2-Propenoic acid; RCRA waste number U008; UN 2218 (DOT) CHEMICAL/PHARMACEUTICAL/OTHER CLASS: Copolymer CHEMICAL STRUCTURE: H2C
O
OH
Uses Acrylic acid derivatives treated with heparin are used to coat surfaces of clinical equipment. Acrylic acid is also used as a copolymer component in aerosol hair spray, in plastics, in molding powder for signs, in paint formulations, in leather finishing, in paper coatings, and in latex applications to prevent premature coagulation. It is also used in the production of hydrogels used for contact lenses.
Background Information For more than decades, acrylic acid has served as an essential building block in the production of some of our most commonly used industrial and consumer products. Approximately two-thirds of the acrylic acid manufactured in the United States is used to produce acrylic esters – methyl acrylate, butyl acrylate, ethyl acrylate, and 2-ethylhexyl acrylate – which, when polymerized, are ingredients in paints, coatings, textiles, adhesives, plastics, and many other applications. The remaining one-third of the acrylic acid is used to produce polyacrylic acid, or crosslinked polyacrylic acid compounds, which have been successfully used in the manufacture of hygienic
Inhalation, skin and eye contact, and ingestion are the most common exposure pathways. Acrylic acid is available as a colorless liquid.
Toxicokinetics The excretion half-life of acrylic acid has been found to be 40 min. Both in vivo and in vitro studies of acrylic acid metabolism have produced strong evidence that the metabolism proceeds by a mitochondrial biochemical pathway for propionic acid metabolism that normally functions in the body at the final stages of breakdown of fatty acids and the production of intermediates for the tricarboxylic acid cycle. It is primarily excreted as carbon dioxide through the lungs. 3-Hydroxypropionate has been found to be a major metabolite. Part of acrylic acid also binds to glutathione and is excreted as the cysteine conjugate in the urine. Some part of acrylic acid can also be converted to acrylyl-CoA and reacts with glutathione to be excreted as cysteine conjugate.
Mechanism of Toxicity Acrylic acid causes toxicity by rapid polymerization in the presence of light, heat, and oxygen and thereby interfering with the incorporation of thymidine into DNA and uracil into RNA and inhibits protein synthesis.
Acute and Short-Term Toxicity (or Exposure) Animal
Acrylic acid has been tested on mice, rats, and rabbits. The toxicity of acrylic acid in animals is similar to that found in humans. Human
Acrylic acid is corrosive to skin. Acrylic acid vapor can cause moderate to severe skin and eye irritation.
46
Acrylonitrile
It can also cause forestomach edema. Acute exposure can be corrosive to the skin, eyes, nose, and mucous membranes of the upper respiratory and gastrointestinal tracts. Inhalation of vapors may produce burning sensation, cough, nasal discharge, sore throat, labored breathing, headache, nausea, vomiting, confusion, dizziness, and unconsciousness.
Chronic Toxicity (or Exposure) Animal
Animals exposed via chronic inhalation developed lethargy, weight loss, kidney abnormalities, embryotoxicity, and inflammation to the upper respiratory tract and gastric mucosa.
nine species of chlorophyceae algae, 10 species of rhodophyceae algae, and in the rumen fluid of sheep. If released to air, a vapor pressure of 3.97 mmHg at 25 1C indicates acrylic acid will exist solely as a vapor in the ambient atmosphere. Vapor-phase acrylic acid will be degraded in the atmosphere by reaction with photochemically produced hydroxyl radicals; the halflife for this reaction in air is estimated to be 2 days. If released to soil, acrylic acid is expected to have very high mobility. Volatilization from moist soil surfaces is expected to be slow. Acrylic acid may potentially volatilize from dry soil surfaces based upon its vapor pressure. If released into water, acrylic acid is not expected to adsorb to suspended solids and sediment in the water column. Biodegradation under both aerobic and anaerobic conditions is expected to occur.
Human
Repetitive exposure to acrylic acid may induce mucosal forestomach hyperplasia.
Clinical Management Exposure should be terminated as soon as possible by moving the victim to fresh air. The skin, eyes, and mouth should be washed with copious amounts of water. Contaminated clothing should be removed and isolated. The victim should be kept calm and normal body temperature should be maintained. Artificial respiration should be provided if the breathing has stopped. Treatment is usually symptomatic.
Exposure Standards and Guidelines Occupational Safety and Health Administration: 8 h time-weighted average (TWA) is 2 ppm. Worker exposure levels may exceed three times the threshold limit value (TLV) TWA for no more than a total of 30 min during a work day, and under no circumstances should they exceed five times the TLV TWA, provided that the TLV TWA is not exceeded. National Institute for Occupational Safety and Health (NIOSH) recommended exposure limit – 10 h TWA: 2 ppm (6 mg m 3).
See also: Polymers.
Environmental Fate Acrylic acid’s production and use in the manufacture of plastics, paint formulations, leather finishings, paper coatings, and in medicine and dentistry for dental plates, artificial teeth, and orthopedic cement may result in its release to the environment through various waste streams. Acrylic acid has also been identified in
Relevant Websites http://www.epa.gov – Acrylic Acid (from the US EPA’s Technology Transfer Network Air Toxics Website). http://www.inchem.org – Acrylic Acid (Environmental Health Criteria 191) from the International Programme on Chemical Safety, 1997.
Acrylonitrile Raja S Mangipudy and Harihara M Mehendale
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CHEMICAL FORMULA: C3H3N
& 2005 Elsevier Inc. All rights reserved.
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CHEMICAL ABSTRACTS SERVICE REGISTRY NUMBER: CAS 107-13-1 SYNONYMS: Acritet; Carbacryl; Propenenitrile; Ventox; Vinyl cyanide; TL 314 CHEMICAL/PHARMACEUTICAL/OTHER CLASS: Industrial chemical; Solvent
Acrylonitrile is used in the manufacture of acrylic fibers and in the plastic surface coatings and adhesive industries. It is also used as a pesticide/fumigant. It is a chemical intermediate in the synthesis of antioxidants, pharmaceutical dyes, surface-active agents, and in reactions requiring the cyanoethyl group.