Summary of April 23, 2007 OMB Meeting

Attendees:  

Steve Risotto, Halogenated Solvents Industry Alliance (HSIA)

Paul Dugard, HSIA

Caffey Norman, Patton Boggs representing HSIA

George Rusch, Honeywell

Amy Flynn, Office of Management and Budget (OMB)

Nancy Beck, OMB

Art Fraas, OMB

Jeff Cohen, Environmental Protection Agency (EPA)

Margaret Sheppard, EPA

Subject:  EPA’s Proposed Rulemaking on n-Propyl Bromide (nPB)

	Mr. Fraas began the meeting by explaining that it is a meeting under
Executive Order 12866.  The sign-in sheet and any materials submitted
during the meeting will go on OMB’s website.

	Dr. Rusch provided an overview of how occupational exposure limits
(OELs) are developed (attachment).  He said that he has worked with the
American Industrial Hygiene Association on their Workplace Environmental
Exposure Limit Committee and he has assistant EPA with its committee on
AEGLs (Emergency Guidance Limits).  He mentioned that the California
Dept. of Health Services has suggested 1 ppm and the American Conference
of Governmental Industrial Hygienists (ACGIH) has set an OEL of 10 ppm
for nPB.  Dr. Rusch provided a number of alternate derivations of an OEL
for nPB based on both neurotoxic and reproductive effects and both
animal and human data, including studies from 2000 to 2007
(attachments).  All the derivations resulted in OELs for nPB between 1
and 10 ppm. 

	Dr. Dugard also provided comments on the recommended AEL of 25 ppm in
EPA’s June 2003 proposal (attachment).  He mentioned that
neurotoxicity has grown in concern since 2003, particularly based on new
cases in humans.  He suggested that EPA should consider both male and
female reproductive effects, and should perform benchmark dose modeling
of female reproductive effects.

	HSIA representatives mentioned the exposure limits mentioned on product
literature and material safety data sheets by nPB manufacturers:

Chemtura--10 ppm

Arkema—5 ppm

ICL (Israeli Chemicals Limited)—references ACGIH value of 10 ppm

Albemarle—25 ppm (2003)

Attached studies:

Ichihara, 2000.  “Ichihara G., Yu X., Kitoh J., et al. 2000.
Reproductive toxicity of 1-bromopropane, a newly introduced alternative
to ozone layer depleting solvents, in male rats.  Toxicol Sciences
54:416-423. (Docket A-2001-07, II-A-7)

Ichihara G., Kitoh J., Yu, X., et al., 2000. 1-Bromopropane, an
alternative to ozone layer depleting solvents, is dose-dependently
neurotoxic to rats in long-term inhalation   exposure.  Toxicol Sciences
55:116-123.  (Docket A-2001-07, II-A-8)  (Hand-written note on front
page:  “Rat is insensitive model for neurotoxicity – short nerve
fibers”)

Wang et al., 2003.   H. Wang, G. Ichihara, H. Ito, K. Kato, J. Kitoh, T.
Yamada, X. Yu, S. Tsuboi, Y. Moriyama, and Y. Takeuchi. 2003. 
“Dose-Dependant Biochemical Changes in RateCentral Nervous System
after 12-Week Exposure to 1-Bromopropane”  NeuroToxicology 24: 199-206
 (EPA-HQ-OAR-2002-0064-0088)

Yamada T. et al., 2003.  Exposure to 1-Bromopropane Causes Ovarian
Dysfunction in Rats. Toxicol Sci 71:96-103  (EPA-HQ-OAR-2002-0064-0097)

Honma et al., 2003.  Honma, T, Suda M, Miyagawa M. “Inhalation of
1-bromopropane causes excitation in the central nervous system of male
F344 rats.” Neurotoxicology. 2003 Aug; 24 (4-5):563-75. 
(EPA-HQ-OAR-2002-0064-0138)

Ichihara et al., 2004. Gaku Ichihara, Weihua Li, Eiji Shibata, Xuncheng
Ding, Hailan Wang, Yideng Liang, Simeng Peng, Seiichiro Itohara,
Michihiro Kamijima, Qiyuan Fan, Yunhui Zhang, Enhong Zhong, Xiaoyun Wu,
William M. Valentine, and Yasuhiro Takeuchi.  Neurological Abnormalities
in Workers of 1-Bromopropane Factory.  Env’l Health Perspectives, 30
June 2004.  (EPA-HQ-OAR-2002-0064-0139)

Majersik, J.J., Caravati, E.M., and Steffens, J.D., 2007.  Severe
neurotoxicity associated with exposure to the solvent 1-bromopropane
(n-propyl bromide).  Clinical Toxicology (2007) 45, 270–276  Available
online at   HYPERLINK
"http://www.informaworld.com/smpp/content~content=a776295616~db=all~orde
r=page" 
http://www.informaworld.com/smpp/content~content=a776295616~db=all~order
=page 

