Acrylic acid

CAS RN: 79-10-7

Exposure Summary

Acrylic acid's production and use in the manufacture of plastics, paint formulations, leather finishes, 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 9 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 mm Hg at 25 deg C indicates acrylic acid will exist solely as a vapor in the atmosphere. Vapor-phase acrylic acid will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals and ozone; the half-lives for these reactions in air are estimated to be 40 hours and 18 days, respectively. Experimental photodegradation rates in distilled water, river water, artificial seawater, and seawater of 2.1X10-4, 5.7X10-4, 4.2X10-4, and 3.9X10-4/sec, corresponding to half-lives of 55, 20, 28, and 30 minutes, respectively. If released to soil, acrylic acid is expected to have very high to high mobility based upon Koc values of 6-137. The pKa of acrylic acid is 4.25, indicating that this compound will exist almost entirely in the anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts. Volatilization from moist soil is not expected because the acid exists as an anion and anions do not volatilize. Acrylic acid may volatilize from dry soil surfaces based upon its vapor pressure. Utilizing the Japanese MITI test, 67.8% of the theoretical BOD was reached in 2 weeks indicating that biodegradation may be an important environmental fate process. In a 42 day anaerobic screening study using a sewage seed inoculum, 71% of acrylic acid was mineralized. If released into water, acrylic acid is not expected to adsorb to suspended solids and sediment based upon the Koc values. The pKa indicates acrylic acid will exist almost entirely in the anion form at pH values of 5 to 9, and, therefore, volatilization from water surfaces is not expected to be an important fate process. An estimated BCF of 3 suggests the potential for bioconcentration in aquatic organisms is low. Acrylic acid was determined to be stable to hydrolysis at pH 3, 7, and 11. Occupational exposure to acrylic acid may occur through inhalation and dermal contact with this compound at workplaces where acrylic acid is produced or used. Use data indicate that the general population may be exposed to acrylic acid via smoking cigarettes, dermal contact with resin, dental products which may contain small amounts of acrylic acid, and use of consumer products such as floor polish. (SRC)
Find more information on this substance at: PubChem, PubMed