Newly Available Data to be
Incorporated into Pyrethroid Proposed Interim Decisions
Based on a thorough review of recent
data, EPA concluded that there are reliable data to support reducing the
current threefold (3X) Food Quality Protection Act (FQPA) safety factor for pyrethroids to 1X, and
that margin will be safe for infants and children. This reduced safety
factor will be incorporated into the upcoming pyrethroid proposed interim
decisions for registration review.
EPA is required to apply a 10X margin
of safety, or safety factor, to human health risk assessments to account
for potential prenatal and postnatal toxicity of infants, children and
pregnant women when exposed to pesticides. The law allows a different
margin of safety only if the Agency has reliable data supporting a
conclusion that the revised safety factor would protect infants and
children.
The Agency considers the FQPA safety
factor to have two components: one assigned to pharmacokinetic (PK)
differences and another for pharmacodynamic (PD) differences. The PK
component refers to the process of chemicals being absorbed, distributed,
metabolized and excreted from and in the body. The PD component refers to
how a chemical affects the body’s tissue.
In 2010, EPA reviewed the data relevant
to assessing the health risks of pyrethroid exposure to infants and
children and found that they supported the removal of the safety factor
for PD. However, the data were insufficient to change the PK portion of
the uncertainty factor, thus leaving a 3X safety factor
More recently, EPA has performed a new
evaluation of available guideline and literature studies, as well as data
generated by the Council for the Advancement of Pyrethroid Human Risk
Assessment. The Agency concluded that the FQPA safety factor for
pyrethroids should be reduced to 1X for all populations (1X for PD and 1X
for PK) because the data indicate that there is no increased sensitivity,
or in other words, there are no PK differences between adults and
children.
Pyrethrins and pyrethroids are
insecticides widely used in and around households, including on pets.
They are also used in treated clothing, mosquito control, and
agriculture.
We invite stakeholders to review the
methodology and EPA’s conclusion to lower the FQPA Safety factor. EPA
will be accepting comments on the white paper once the Federal Register
notice announcing availability of the pyrethroid Proposed Interim
Registration Review Decisions is published later this year. Once the
Proposed Interim Decisions are published, comments should be submitted to
www.regulations.gov under docket # EPA-HQ-OPP-2008-0331.
|
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.