1-Bromopropane 1


1-Bromopropane 1 :

What is 1-Bromopropane (1-BP)? Also known as n-propyl bromide (nPB), is a solvent (CAS 106-94-5) with several commercial applications. Use of 1-BP has increased in workplaces over the past 20 years. 1-BP is a solvent that is used in degreasing, dry cleaning, spray adhesives, and aerosol solvents. Occupational exposure to 1-BP has been linked to neurological illnesses. Animal studies show that 1-BP may also cause cancer and reproductive disorders. Controls and personal protective equipment are available to protect workers from 1-BP exposure. 1-BP is often found in products used in: (1) Vapor and immersion degreasing operations for cleaning metals, plastics and electronic and optical components; (2) Adhesive spray applications; (3) Dry cleaning; and (4) Solvent sprays used in operations like asphalt production, aircraft maintenance, and synthetic fiber manufacturing. Health Effects of 1-BP and How Workers Are Exposed: Exposure to 1-BP can cause irritation (for example, of the eyes, mucous membranes, upper airways and skin) and can damage the nervous system. Neurologic effects can appear as headaches, dizziness, loss of consciousness, slurred speech, confusion, difficulty walking, muscle twitching, and/or loss of feeling in arms and legs [Ichihara et al. 2012]. These effects may continue among affected persons even after exposure to 1-BP has ended [Majersik et al. 2007]. As with many other solvents, workers can be exposed to 1-BP by breathing in vapor or mists of spray. Workers might also be exposed if the chemical touches their skin because it can be absorbed [Hanley et al. 2006; Frasch et al. 2011]. Additionally, the risk of health effects to workers increases the longer they work with or near 1-BP. Impacts on health have been seen in workers after exposures for as little as two days, although symptoms are more commonly associated with longer exposure [Ichihara et al. 2012]. Federal OSHA does not currently have a specific exposure standard for 1-BP; however, employers are required by law to keep their workers safe from this recognized hazard. Degreasing, spray adhesive, aerosol solvent and dry cleaning operations expose workers to air concentrations of 1-BP greater than the limits set by the California Occupational Safety and Health Administration (Cal-OSHA) and the American Conference of Governmental Industrial Hygienists (ACGIH). California has adopted a 5 ppm (parts per million) time-weighted average PEL (permissible exposure limit) along with a skin notation which means that a worker's skin, eyes, and mouth should be protected from any contact with 1-BP; this limit was based on reproductive and developmental toxicity (observed in animal studies) and technological feasibility assessments from industry [CA DIR 2009]. ACGIH currently recommends a 10 ppm time-weighted average threshold limit value but has proposed lowering the value to 0.1 ppm [ACGIH 2013]. Case Study Example: Six foam cushion gluers who were exposed to 1-BP vapors from spray adhesives were seen in a medical clinic for neurotoxicity. The workers had been employed at the facility from 3 months to 3 years. All patients complained of slow onset of lower extremity pain or numbness. Five of six complained of difficulty walking, and on examination had leg spasms, loss of sensation in limbs, and muscle twitching. Three patients initially had nausea and headache. Serum bromide concentrations and air samples were obtained to assess exposure. A seven hour time-weighted average air concentration of 1-BP was found to be 108 ppm (range 92-127 ppm). Two years after exposure, the two most severely affected patients still had trouble with walking and loss of feeling in their legs and they, along with a third patient, continued to feel pain most of the time. Studies in Experimental Animals: Animal studies suggest that 1-BP exposure is associated with reduced blood cell counts and immunosuppression along with toxicity to the liver and reproductive and nervous systems. Furthermore, the National Toxicology Program (NTP) is considering classifying 1-BP as reasonably anticipated to be a human carcinogen [NTP 2013]. This designation was based primarily on increased lung, large intestine and skin cancers seen in rodents that were exposed to 1-BP in the air [NTP 2011]. See more from topic source: https://www.osha.gov/html/a-z-index.html

No records Found
afaatim.com copyright © April 2016 Dr.K.R.Kamaal. All rights reserved