# National Clothesline

HSIA asks EPA to add nPB to hazardous air pollutants list

The Halogenated Solvents Industry Alliance has petitioned EPA to list n-propyl bromide (nPB) as a hazardous air pollutant under Section 12 2 of the Clean Air Act. The listing would result in regulation of significa nt sources of nPB, HSIA said. HSIA, which represents manufacturers of manufacture rs, producers, distributors and commercial users of perchloroethylene and other hal ogenated solvents, noted that nPB is being marketed as an ‘unregulated’ alternative to chlorinated solvents i n a variety of applications. “Chlorinated solvents are listed as hazardous air p ollutants and industrial sources of chlorinated solvent emissions are stringently regul ated, ” HSIA said in its petition . “NPB is being aggressively marketed as an unregulated alter native to chlorinated solvents. Indeed sales literature for nPB emphasized that is it esse ntially unregulated. ” As a drycleaning solvent, nPB is sold under the tra de names DrySolv and Fabrisolv. Responding to the increasing usage of nPB, the Occu pational Safety and Health Administration nominated nPB for further study in t he National Toxicology Program. HSIA cited the NTP study, recently submitted for peer re view, that concluded there was clear evidence for carcinogenicity in female rats and mic e exposed to nPB. HSIA also noted that observations in one group of w orkers suggested the signs of neurotoxicity are detectable at levels of one to fi ve parts per million in air exposure averaged over eight hours “Observations of the toxic effects of nPB in animal s and workers exposed to it demonstrate that exposed populations, whether workers or the ge neral population, may face serious health effects which could include neurological effects, cancer and reproductive effects, ” HSIA said. According to the petition, global production of nPBhas been growing and was estimated at 20,000 to 30,000 metric tons in 2007. China is amon g the leading producers with about 20,000 metric tons in 2008 of which approximately 4 0 percent was exported. Use of the solvent in the United States was reporte d at 5,000 metric tons and growing at a rate of 15 to 20 percent a year. The petition also cited a study on the use of nPB i n New Jersey drycleaning plants which noted that “some green or organic solvents in the drycleaning industry intended to replace perc may result in significant exposures above acce ptable guidelines among some workers. ” The study found exposures to nPB in two of three sh ops measured that were greater than the American Conference of Governmental Industrial Hygienists threshold limit value of 10 parts per million for nPB. The highest exposure rec orded was 54 ppm. “Many drycleaning operators may not realize that th e machine components and settings must be changed when converting from perc to nPB, ” the study reported. “Not performing these modifications may result in overheating and s ignificant leaks in the drycleaning equipment. ” The elevated exposures may have resulted from leaksdue to normal machine wear over time, ineffective maintenance, and from the incompa tibility of nPB with gasket materials, the study said. “Careful consideration and study of potential expos ures and health effects among workers 

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6/ 17/2014 http://web.newsguy.com/natclo/1012/npb.htmusing new chemicals or processes must precede any regulatory attempt to facilitate substitution for environmental purposes, ” the report said. 

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6/ 17/2014 http://web.newsguy.com/natclo/1012/npb.htm