Document ID: EPA-HQ-OPP-2003-0248-0036
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2008-04-16T04:00Z

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

	WASHINGTON, D.C. 20460

							                                               OFFICE OF

				PREVENTION, PESTICIDES

	AND TOXIC SUBSTANCES

MEMORANDUM

Date:		April 9, 2008

Subject:	Issues to Consider in Commenting on the Revised Risk
Assessments for the Wood Preservative Uses of Creosote (Case 0139)

From:		Jacqueline Campbell-McFarlane, Chemical Review Manager

Registration Management Branch I

Antimicrobials Division

To:		Creosote Docket (EPA-HQ-OPP-2003-0248)

The Environmental Protection Agency’s (EPA or “the Agency”) Office
of Pesticide Programs (OPP) has completed its revised risk assessments
in support of the reregistration eligibility decision (RED) for the wood
preservative uses of creosote.  This document was prepared to help
identify for potential respondents the kind of information that the
Agency believes would be useful in making its reregistration decision. 
The revised risk assessments and other support documents are available
for public comment in public docket # EPA-HQ-OPP-2003-0248 at  
HYPERLINK "http://www.regulations.gov/"  http://www.regulations.gov/ .

SECTION I: BACKGROUND

EPA is releasing for public comment its revised risk assessments to
support the reregistration eligibility decisions for the three heavy
duty chemical wood preservatives: chromated arsenicals,
pentachlorophenol, and creosote.  Case 0139, Creosote, a restricted use
pesticide, was first registered in the United States in 1948 to protect
wood from rotting due to insect and microbial attack.  Presently, 13
products are registered as industrial wood preservatives for above and
ground wood protection treatments, as well as treating wood in marine
environments.    

Publishing revised risk assessments and risk mitigation/exposure
reduction options for public comment is part of EPA’s Six-Phase public
participation process.  The Agency uses this process to involve the
public in developing pesticide reregistration decisions.  After the
60-day public comment period closes, EPA will evaluate the responses
received, update its revised risk assessments as appropriate, and issue
its final risk assessments and reregistration eligibility decision.  The
RED document is currently scheduled to be released in September 2008 and
will present the Agency’s determination on which wood preservative
uses of creosote meet the “no unreasonable adverse effects” standard
of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA).  

The preliminary risk assessment does not assess non-pressure treatment
uses since EPA issued cancellation orders in August 2004 accepting the
voluntary use termination/ product cancellation requests to either amend
current label language to delete non-pressure treatment uses of creosote
or to cancel the affected products (69 FR 55623).  This action canceled
three pesticide registrations and terminated certain uses of seven
pesticide registrations as of December 31, 2004. EPA’s risk assessment
for previously registered non-pressure treatment uses is available in
docket # EPA-HQ-OPP-2003-0248.

SECTION II: CHANGES TO THE RISK ASSESSMENTS

EPA has reviewed new information since the previous risk assessments
were released including submissions received during the Phase 3 public
comment period that ended on December 26, 2003.  Based on this new
information, in addition to making numerous clarifications and minor
changes throughout the documents, EPA has incorporated the following
significant revisions:

The 2003 human health risk assessment relied on benzo(a)pyrene as an
indicator of creosote cancer risk because creosote-specific data were
not available.  Data are now available for creosote to assess cancer
risk.  In conjunction with Health Canada’s Pest Management Regulatory
Agency (PMRA), a quantitative risk assessment on carcinogenicity of
creosote has been performed, changing the cancer slope factor from 7.3
(mg/kg/day)-1 to   6.28 x10-3 (mg/kg/day)-1.

The 2003 risk assessment estimated a dermal absorption value of 50%. 
Newly available data indicate that the dermal absorption is 5%.  

All scenarios pertaining to non-pressure treatment uses have been
deleted in this assessment based on the voluntary cancellation of all
non pressure treatment uses of creosote in 2004.

The Ecological Effects Risk Assessment was updated to address concerns
regarding polycyclic aromatic hydrocarbons (PAHs) raised by the U.S.
National Oceanic and Atmospheric Administration (NOAA) and the Fish and
Wildlife Service (FWS).  In addition, the Sookie Basin field study data
were evaluated.

SECTION III: QUESTIONS

This section provides questions to elicit and guide comments on EPA’s
revised risk assessments.  Note that these questions are offered for
comment and are not meant to imply that EPA intends to complete or
require any of the measures herein.  When submitting comments, please
identify the question(s) you are addressing and include discussions,
explanations, and references where possible.

1. Occupational Risks

Cancer and non-cancer risks posed to treatment plant workers exceed the
Agency’s level of concern.  To reduce similar risks for other
chemicals, EPA has historically required implementation of risk
reduction measures.  These measures are chemical- and risk-specific, and
might include limiting the ways in which or products to which the
chemical may be applied, additional personal protective equipment (PPE),
and/or restricted entry/re-entry intervals.  Risk reduction measures
might also include pressure treatment plant “engineering controls”
such as hydraulic doors, hydraulic bridge rails, and/or a ventilation
system.  

What practical and effective measures might EPA implement to reduce
worker exposure during treatment (i.e., pressure treatment workers)?

If the measures identified in 1.a. were to be implemented, what are the
potential economic and/or other impacts to small-, medium-, and
large-sized treatment plants?

If the measures identified in 1.a. were to be implemented, approximately
how much time would it take to implement each measure at a small-,
medium-, and large-sized treatment plant?

What air monitoring data are available in and around plants that
currently use creosote as wood preservatives?

2. Ecological Risks

The ecological risk assessment for creosote indicates a potential for
exposure of listed fish and aquatic invertebrate species.  The aquatic
exposure modeling has been refined and additional data from field,
microcosm, mesocosm, and laboratory studies included to assess the
potential for acute and sublethal risks to fish and aquatic
invertebrates exposed in the water column or in aquatic sediment. 
Because guideline toxicity studies are not available for these PAHs, the
Agency used the best available information to evaluate the risks
associated with creosote use.  

a.	What practical and effective measures might EPA implement to reduce
ecological exposure associated with the use of creosote-treated wood?

b.	What air monitoring data are available in and around plants that
currently use creosote as a wood preservative?

c.	What data are available to evaluate the effects of PAHs on fish, or
aquatic invertebrate species?

  

3. Benefits and Alternatives

EPA has reviewed submissions received during the Phase 3 public comment
period that ended on December 26, 2003, as well as Creosote Council’s
December, 2007 presentation on “Creosote Benefits” (available in
docket # EPA-HQ-OPP-2003-0248).  EPA is also in the process of
finalizing its own benefits, alternatives, and economic analyses for the
three heavy duty chemical wood preservatives.  These documents will also
be posted in docket # EPA-HQ-OPP-2003-0248.

Are there unique uses and benefits of creosote that are not already
captured in the existing documents?

What alternatives, either chemical or non-chemical, exist for heavy duty
wood preservative uses of creosote that are not already captured in the
existing documents?

What information is available on best management practices for using
creosote to pressure treat wood (recommended application methods/times,
storage/disposal instructions, etc.)?  

Page   PAGE  1  of   NUMPAGES  4 

 US EPA. Human Health Risk Assessment for the Reregistration Eligibility
Decision Document (RED)  of Creosote. March 31, 2008.