June 28, 1996
Mr. Daniel L. Prince
Post Office Box 1281
West Caldwell, New Jersey 07006
Dear Mr. Prince:
Thank you for your letter of February 5, concerning Microgen Inc.
disinfectant products "D-125" and "Public Places." Please excuse our delay
in responding, however, we wanted to give you a comprehensive response.
The Occupational Safety and Health Administration (OSHA) has reviewed the
information provided by the Environmental Protection Agency (EPA) concerning
Microgen's products, "D-125" and "Public Places." We concur with the EPA
that use of the products designated above is appropriate as a disinfectant
for HBV and HIV provided two conditions are satisfied. First, HBV and HIV
are the only bloodborne pathogens of concern (for example, as in a research
setting), and second, the products are used in the concentrations approved by
EPA. When both conditions are met, we agree that Microgen's disinfectants
"D-125" and "Public Places" are appropriate for use on solid, nonporous,
precleaned enviromental surfaces, and the precleaning of such
However, please note that when other bloodborne pathogens are of concern
neither product is approved as a disinfectant for solid, nonporous,
precleaned environmental surfaces nor for precleaning such surfaces. To
date, the EPA has not approved any Microgen product to be efficacious for
bloodborne pathogens other than HBV or HIV. Therefore, when bloodborne
pathogens other that HBV or HIV are of concern OSHA continues to require the
use of EPA-registered tuberculocidal disinfectants.
We appreciate Microgen's support of safety and health in the workplace. If
you have further questions pertaining to this matter, please contact this
office for further information (202) 219-8036.
Ruth McCully, Director
Office of Health Compliance Assistance
February 5, 1996
Mr. John B. Miles
Director of Compliance Programs
Occupational Safety and
US Department of Labor
200 Constitution Avenue, NW
Washington, DC 20212
Re: Discussion of EPA approved disinfectants to inactivate HBV and HIV in
Dear Mr. Miles:
As a follow-up to our earlier memorandum of 2-1-96, enclosed you will find
additional information regarding the issue of decontamination of HBV and HIV.
Microgen, Inc. has recently received approval from the United States
Environmental Protection Agency (EPA) to market two disinfectant products
(D-125 and Public Places) which inactivate Hepatitis B Virus (HBV) on hard
environmental surfaces, including hard surfaces associated with blood
collection. Furthermore, MICROGEN has received written clarification from
the Centers for Disease Control (CDC) that hospital level disinfectants, such
as our quaternary ammonium disinfectants D-125 and Public Places, can be used
as part of various decontamination programs established for worker safety.
D-125 and Public Places are the first and only products which conform with
the requirements of the EPA,(1) CDC(2) and Occupational Safety and Health
Administration (OSHA).(3) The OSHA Final Rule entitled "Occupational
Exposure to Bloodborne Pathogens" (29 CFR Part 1910.1030) requires that the
use of products registered with the EPA to control HBV and HIV.
FOOTNOTE(1) Microgen EPA Approved labels (enclosed herein) contain
instructions for disinfection of HBV and HIV in blood collection centers.
FOOTNOTE(2) See enclosed letter from Dr. Martin J. Favero of the CDC. Dr.
Favero can be contacted for conformation at: 404-639-6401.
FOOTNOTE(3) The Bloodborne pathogen rule concerns itself with worker
safety. It specifically and repeatedly stipulates that HBV and HIV must be
decontaminated. Note: Control of Tuberculosis does not appear anywhere in
the rule. The rule was first published in the Federal Register on Friday,
December 6, 1991 (Volume 36, Number 235)
It is our understanding that primary intent of the rule is to provide
workers with direct protection against bloodborne pathogens such as HBV and
HIV. When the rule was put into effect there were no EPA approved
disinfectants against both HBV and HIV. Little was known about the
susceptibility of HBV and HIV to liquid chemical germicides. Now, however, a
great deal has been learned.(4) Namely, quaternary ammonium disinfectants
quickly inactivate HBV and HIV even in the presence of five (5%) percent
blood serum and in hard water. We no longer need to exclusively depend upon
agents comprised of phenol, alcohol, glutaraldehyde, or peracetic acid simply
because they inactivate a surrogate organism such as TB. It is a matter of
record that disinfectants formulated with these active ingredients
(phenolics, etc.) suffer from many disadvantages such as human toxicity,
flammability, corrosivity, staining, odor and are very expensive. Given that
these agents (phenolics, etc) are not registered with the EPA to inactivate
HBV and have multiple disadvantages, and given that quaternary ammonium
products are registered with EPA to inactivate HBV and HIV, are less
expensive, more compatible with materials and safer to end-users than the
aforementioned chemical agents (phenols, etc.) and because TB is not a
clinically relevant organism,(5) it seems appropriate for OSHA to immediately
update its policies such that the use of disinfectants registered with EPA to
inactivate HBV and HIV be required.
FOOTNOTE(4) Enclosed find the publication "Methodological Approaches to
Disinfection of Human Hepatitis B Virus", Journal of Clinical Microbiology,
FOOTNOTE(5) Tuberculosis is not spread through blood; it is spread through
A summation of the fundamental reasons why the OSHA should change its
recommendations so that the use of quaternary ammonium compounds with
anti-HBV activity becomes the new standard in infection control are presented
1. It fulfills the requirement and intent of the rule promulgated
by the Occupational Safety and Health Administration as published in the
Federal Register (29 CFR Part 1910.1030, December 6, 1991, pages 64175 to
We respectfully ask that the OSHA revise its policy such that the
inactivation of HBV and HIV by EPA-registered quaternary ammonium
disinfectants will now be emphasized. This will help assure that the OSHA
stays in conformance with the Federal law as well as remaining consistent
with current scientific, regulatory and epidemiological facts.
2. HBV and HIV are clinically relevant organisms in the practice
of blood banking, TB is not.
We would be pleased to answer any questions you may have in this regard. I
will call you to discuss this letter on 2/9/96.
Daniel L. Prince, Ph.D