[Federal Register Volume 65, Number 166 (Friday, August 25, 2000)]
[Pages 51828-51830]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-21784]



[OPP-00673; FRL-6736-5]

Pesticides; Protocols for Testing the Efficacy of Disinfectants 
Against Hepatitis B Virus (HBV); Notice of Availability

AGENCY:  Environmental Protection Agency (EPA).

ACTION:  Notice of availability.


SUMMARY:  The Agency is announcing the availability of guidance titled 
``Protocol for Testing the Efficacy of Disinfectants Used to Inactivate 
Hepatitis B Virus and Corresponding Label Claims.'' Through this 
guidance, EPA expresses its view that the appropriate and preferred 
test relies on in vitro duck assays which use duck hepatitis B virus as 
a surrogate for human hepatitis B virus (HHBV) to evaluate the efficacy 
of disinfectants used to inactivate HHBV. Use of such assays will 
greatly minimize the use of animals for testing. The Agency is also 
making available its responses to comments on the draft protocols that 
were made available for public comment.

FOR FURTHER INFORMATION CONTACT:  Ibrahim Barsoum, Antimicrobials 
Division (7510C), Environmental Protection Agency, 1200 Pennsylvania 
Ave., NW., Washington, DC 20460; telephone number: (703) 308-6417; fax 
number: (703) 308-8481; e-mail address: [email protected].


I. General Information

A. Does this Action Apply to Me?

     This action is directed to the public in general. This action may 
be of particular interest to those persons who manufacture or formulate 
pesticides. Potentially affected categories and entities may include, 
but are not limited to:

                                                          Examples of
           Categories                    NAICS            potentially
                                                       affected entities
Pesticide Producers               32532               Pesticide

    Since other entities may also be interested, the Agency has not 
attempted to describe all the specific entities that may be affected by 
this action. If you have any questions regarding the information in 
this notice, consult the person listed under FOR FURTHER INFORMATION 

B. How Can I Get Additional Information, Including Copies of this 
Document and Other Related Documents?

    1. Electronically. You may obtain electronic copies of this 
document from the Office of Pesticide Programs' Home Page at http://www.epa.gov/pesticides/. You can also go directly to the listings from 
the EPA Internet Home Page at http://www.epa.gov/. To access this 
document, on the Home Page select ``Laws and Regulations,'' 
``Regulations and Proposed Rules,'' and then look up the entry for this 
document under the `` Federal Register--Environmental Documents. '' You 
can also go directly to the  Federal Register  listings at http://www.epa.gov/fedrgstr/.
    2. Fax-on -demand. You may request a faxed copy of the guidance, as 
well as supporting information, by using a faxphone to call (202) 401-
0527. Select item 6067 for the document titled ``Protocol for Testing 
the Efficacy of Disinfectants Used to Inactivate Hepatitis B Virus and 
Corresponding Label Claims.'' Select item 6068 for the document titled 
``Responses to Public Comments on Protocols for Testing the Efficacy of 
Disinfectants Used to Inactivate Hepatitis B Virus.'' You may also 
follow the automated menu.
    3. In person. The Agency has established an official record for 
this action under docket control number OPP-00673. The official record 
consists of the documents specifically referenced in this action, any 
public comments received during an applicable comment period, and other 
information related to this action, including any information claimed 
as confidential business information (CBI). This official record 
includes the documents that are physically located in the docket, as 
well as the documents that are referenced in those documents. The 
public version of the official record does not include any information 
claimed as CBI. The public version of the official record, which 
includes printed, paper versions of any electronic comments submitted 
during an applicable comment period, is available for inspection in the 
Public Information and Records Integrity Branch (PIRIB), Rm. 119, 
Crystal Mall #2, 1921 Jefferson Davis Highway, Arlington, VA, from 8:30 
a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The 
PIRIB telephone number is (703) 305-5805.

II. Background

A. What Guidance Does this Notice Provide?

    EPA has authority through the Federal Insecticide, Fungicide, and 
Rodenticide Act (FIFRA) to register pesticide products, including 
antimicrobial pesticide products, for sale and distribution in the 
United States. FIFRA section 3(c)(5) requires that the composition of a 
pesticide product is such as to warrant the claims made for it, i.e., 
that a product work as claimed. Although registrants must maintain data 
demonstrating efficacy in their files and must submit these data to the 
Agency upon request, EPA does not routinely review efficacy data prior 
to registration of most insecticides, fungicides, herbicides, and non-
public health antimicrobial pesticides. However, for public health 
pesticide products (i.e., those that work against pests in situations 
where they pose public health threats) the Agency reviews efficacy data 
prior to registration. The Agency believes that the potential 
consequences of performance failure for public health products warrant 
this extra precautionary step in the review process. Moreover, for 
public health products intended to control bacteria, fungi and viruses, 
the user is typically unable to determine whether the product is 
working, due simply to the microscopic size of these organisms.

[[Page 51829]]

 Subdivision G of the Pesticide Assessment Guidelines describes the 
efficacy tests routinely used to validate the claims made by 
antimicrobial public health pesticide products. These guidelines are 
available from the National Technical Information Service, 5285 Port 
Royal Road, Springfield, VA 22161 (1-800-553-6847).
    For the past several years, EPA has been engaged in a process to 
identify scientifically and statistically adequate test protocols for 
evaluating the efficacy of disinfectants used to inactivate human 
hepatitis B virus (HHBV). In May 28, 1986 (51 FR 19174), the Agency 
published a Notice of Amendment to Policy regarding certain virucidal 
claims. Specifically, the Notice stated that virucidal claims for HBV 
would be permissible only for sterilizer products until such time that 
acceptable protocols to demonstrate virus isolation and disinfectant 
product efficacy could be developed.
    In 1990, the Agency received and approved a chimpanzee testing 
protocol to support HBV efficacy claims for hard, environmental surface 
disinfection products. While the data were being generated using the 
approved protocol, a General Accounting Office (GAO) Report was issued 
(August 1990) that criticized the Agency for accepting test methods 
without criteria or a systematic review process. In response to this 
criticism, the Agency initiated a process whereby new protocols would 
undergo external review by scientific experts. In 1995, as a result of 
this change in process, the chimpanzee protocol was subjected to 
external review by experts working in various scientific institutions, 
including the Food and Drug Administration (FDA), Center for Disease 
Control (CDC), National Institutes of Health (NIH), and two university 
medical schools. The experts were asked to review the data generated 
using the EPA-approved protocol as well as similar data developed by 
Bond et al. 1983, at CDC. After careful review of all comments 
received, the Agency concluded that the chimpanzee data submitted by 
the applicant, when considered together with the data developed by Bond 
et al. 1983, were sufficient to support a label claim of disinfection 
against HBV.
    During the 1995 external review process for the chimpanzee 
protocol, several experts urged the Agency to accept data developed 
using a surrogate virus, thus making available an alternative to 
chimpanzee testing. One expert stated that it would be unjustified to 
permit the use of any type of animal for germicidal testing and that 
such testing could be avoided though the use of properly designed in 
vitro methods. As a result of these concerns, the Agency began to seek 
alternative means of testing the product performance of disinfectant 
products intended for inactivation of HBV. One of the steps in this 
process was consultation with the FIFRA Scientific Advisory Panel (SAP) 
in September 1997. At that meeting the questions posed to the Panel 
were as follows:
    1. If the Agency decides to replace the chimpanzee test used in 
testing the efficacy of disinfectants against human hepatitis B-type 
virus, what test methodologies could be used as a replacement? Two 
possibilities that have been proposed to the Agency are the duck 
hepatitis B Virus Test (DHVT) and the Morphological Alteration and 
Disintegration Test (MADT). Could one or both of these tests be used to 
test for efficacy against HHVB?
    2. If a surrogate test system (i.e., the DHVT) is found to be 
acceptable for efficacy testing using HVB, would the results be 
sufficient to allow the registrant to make a label claim that the 
product was efficacious against HHBV, even though it was tested against 
a surrogate virus (i.e., duck hepatitis B virus) and not the human 
    Briefly, the SAP's responses to these questions were as follows. 
The Panel concurred with the notion that it is unethical to continue to 
require testing using a species of primates, chimpanzees, where 
alternative methods are available, and observed that there is a long 
history of using surrogate microbes to assess the efficacy of 
disinfection/sterilization technologies against various classes of 
microorganisms. The Panel stated that the duck hepatitis B virus (DHBV) 
constitutes an appropriate HHBV surrogate and added that an advantage 
to this surrogate is that the DHBV can be utilized in both in vivo and 
in vitro settings. In particular, the Panel stated that the DHBV 
approach would allow for sufficient numbers of test samples to be used 
for each set of experimental conditions so that statistically 
significant results can be obtained. The Panel discussed the 
possibility that DHBV may be more resistant to germicidal chemical 
activity but, in essence, felt that even if this were true it was not a 
serious issue, given that hepatitis B-type viruses have been 
demonstrated to be sensitive to the activity of a wide spectrum of 
liquid chemical germicides including low level disinfectants. While the 
panel did not discuss the MADT alternative at great length or exclude 
the possibility of its use, it did observe that the test is only 
subjective. The Panel stated its belief that registrants who use DHBV 
could make a label claim of product efficacy to either the specific 
virus or in the alternative to perhaps the whole virus family as a 
group. The example of claims against Mycobacterium tuberculosis by 
testing against Mycobacterium bovis was cited as precedent for the use 
of a surrogate in disinfectant efficacy testing. If tests validate that 
a surrogate virus is less or equally susceptible to inactivation by 
disinfectants, then logically any product which demonstrates efficacy 
against the surrogate virus should be allowed a label claim against 
    The responses of the SAP to these questions provided invaluable 
guidance to the Agency in its pursuit of scientifically adequate test 
protocols for evaluating the efficacy of disinfectants used to 
inactivate HHBV. The Antimicrobials Division of the Office of Pesticide 
Programs sponsored a workshop in July 1998 to discuss alternative 
models for testing disinfectants against HHBV. The workshop was 
attended by representatives from academia, research centers, testing 
laboratories, and industry. Presentations were given by experts in 
hepatitis on various animal models of HBV infection followed by 
technical presentations on in vitro  and in vivo duck models of 
infection that might be used in testing disinfectants for use against 
HHBV. Presentations were followed by a discussion on criteria to be 
used in decision making about surrogate model(s) and proposed labeling 
claims of registered products. Many participants in the workshop 
proposed that EPA leave the label claim broad, such as ``effective 
against HBV'' or ``hepadnavirucidal'' and not add information about the 
test organism. Submitted protocols were evaluated and discussed by all 
participants. At the end of the workshop an outline was presented, 
showing the Agency's implementation plans for allowing products to be 
registered with HHBV label claims using surrogate animal models. 
Subsequently, the Agency published an FR Notice on December 30, 1998 
(63 FR 71924) (FRL-6051-4) announcing the availability of and 
requesting comments on two protocols for testing the efficacy of 
disinfectants against HHBV. These protocols were for an in vitro assay 
using duck hepatocytes and DHBV and an in vivo assay using ducklings 
and DHBV.
    The Agency received 12 sets of comments in response to that Notice. 
Comments were received from consultants, an animal rights organization, 
university scientists, the regulated industry, the California

[[Page 51830]]

Department of Pesticide Regulation, and private organizations. These 
comments in their entirety are available in the public docket (OPP-
00673). Many of the comments were similar in content, and pertained to 
general issues concerning Agency policy or specific sections within the 
protocols themselves. To facilitate review and consideration of the 
comments, the Agency has grouped comments addressing similar issues 
    After the Agency reviewed the comments, it reached three 
     1. It is the Agency's position that duck HBV serves as an adequate 
surrogate for human HBV and that the in vitro assay is sufficiently 
sensitive to preclude the need for any in vivo testing. The Agency is 
adopting, where possible, policies and data requirements that minimize 
animal testing, and when animal testing must be conducted, EPA is 
committed to reducing the number of animals needed for testing, 
reducing the pain and suffering of the test animals, and whenever 
scientifically-defensible, replacing animals with validated non-animal 
test systems. Therefore, relying heavily on the recommendations of the 
SAP, the Agency expects to rely on the use of the in vitro duck 
protocol as the method for evaluating the efficacy of disinfectants 
used to inactivate HHBV. Notwithstanding its commitment to maximize the 
reduction or elimination ofanimal testing where feasible, the Agency 
recognizes that some testing may already have been initiated or 
completed using the duck in vivo methodology as of the date of this 
Notice. On a case-by-case basis, the Agency will generally accept these 
data, if deemed valid, to support a registration.
     2. Label claims against either the Hepadnavirus family or, more 
specifically, HHBV will be permitted when supported by adequate 
efficacy claims as described below. In addition, the following label 
claim language will be deemed acceptable: ``effective against HBV.'' 
The Agency believes that these label claims can be supported by 
appropriate DHBV efficacy tests, since the surrogate DHBV has been 
shown to be a reliable predictor of resistence to chemical disinfection 
for the Hepadnavirus family as a whole.
     3. To ensure that the  in vitro duck method has been adequately 
validated, data should be provided from at least two independent 
laboratories for each product tested (two batches per product per 
laboratory). The validation of a protocol requires the use of a common 
positive control disinfectant to be tested concurrently with all new 
products. The recommended control is alkyldimethylammonium chloride 
(BTC-835, Onyx Chemical Co.) (AOAC Official Methods of Analysis, 
Chapter 6, p. 136, 15th Edition, 1990). This agent should serve as both 
an intra-laboratory and an inter-laboratory control and will be used 
for analyzing the reproducibility of the efficacy data results for that 
particular protocol. In order to obtain the necessary inter-laboratory 
data, all submissions must additionally be subjected to confirmatory 
testing, with the common positive control, at a second laboratory test 
facility. It is critical for the Agency to know that a test method is 
repeatable; i.e., that there is an appropriately small standard 
deviation of log reduction (LR) values found when the test is repeated 
on different occasions in the same laboratory as well as when the test 
is conducted in different laboratories. The use of the common positive 
control and the generation of confirmatory data in a second testing 
facility will achieve these goals. A more detailed document outlining 
the criteria for validation is available electronically under the 
section titled ``Related Documents'' section of the electronic version 
of this Notice (``Protocol for Testing the Efficacy of Disinfectants 
Used to Inactivate Hepatitis B Virus''). This document may also be 
requested by mail directly from the Agency (refer to FOR FURTHER 
INFORMATION CONTACT section of this Notice).

B. Guidance Documents

    The guidance discussed in this notice is intended to provide 
guidance to EPA personnel and to pesticide applicants and registrants. 
This notice is not binding on EPA, applicants and registrants, and EPA 
may depart from the guidance where circumstances warrant and without 
prior notice. Registrants and applicants may propose altenatives to the 
protocols described in this notice and the Agency will assess them on a 
case-by-case basis.

List of Subjects

    Environmental protection, Administrative practice and procedure, 
Agricultural commodities, Pesticides and pests.

    Dated: August 17, 2000.

Marcia E. Mulkey,
Director, Office of Pesticide Programs.

[FR Doc. 00-21784 Filed 8-24-00]