Lydia Wegman/RTP/USEPA/US

05/01/2008 08:41 AM

	

To

"King, Heidi R." <Heidi_R._King@omb.eop.gov>

cc

"Fraas, Arthur G." <Arthur_G._Fraas@omb.eop.gov>, Tricia
Crabtree/RTP/USEPA/US@EPA, Karen Martin/RTP/USEPA/US@EPA, Robert
Meyers/DC/USEPA/US@EPA, Jason Burnett/DC/USEPA/US@EPA

Subject

RE: air-to-blood ratio section









We have talked to Jennifer Seed and Maria Doa at OPPTS.  They agree with
the footnote as written.  They are available to talk with you and us at
any time.  When would you like to talk?

-----"King, Heidi R." <Heidi_R._King@omb.eop.gov> wrote: -----

To: Lydia Wegman/RTP/USEPA/US@EPA, "Fraas, Arthur G."
<Arthur_G._Fraas@omb.eop.gov>

From: "King, Heidi R." <Heidi_R._King@omb.eop.gov>

Date: 05/01/2008 07:33AM

cc: Tricia Crabtree/RTP/USEPA/US@EPA, Karen Martin/RTP/USEPA/US@EPA,
Robert Meyers/DC/USEPA/US@EPA, Jason Burnett/DC/USEPA/US@EPA

Subject: RE: air-to-blood ratio section

 

I haven’t heard from OPPTS yet on the LRRP rule language; I’ll keep
trying, but if someone else has made contact pls let me know. 

 

Thank you, 

 

heidi 

 

From: Wegman.Lydia@epamail.epa.gov [mailto:Wegman.Lydia@epamail.epa.gov]


Sent: Thursday, May 01, 2008 12:46 AM 

To: King, Heidi R.; Fraas, Arthur G. :PersonName

Cc: Crabtree.Tricia@epamail.epa.gov; Martin.Karen@epamail.epa.gov;
Meyers.Robert@epamail.epa.gov; Burnett.Jason@epamail.epa.gov 

Subject: Re: air-to-blood ratio section 

 

We'll plan to discuss this later this morning.   

 ----- Original Message ----- 

  From: "King, Heidi R." [Heidi_R._King@omb.eop.gov] 

  Sent: 05/01/2008 12:16 AM AST 

  To: Lydia Wegman; " Fraas, Arthur G. :PersonName"
<Arthur_G._Fraas@omb.eop.gov> 

  Cc: Tricia Crabtree; Karen Martin; Robert Meyers; Jason Burnett 

  Subject: RE: air-to-blood ratio section 

 

Lydia , 

Thank you for this draft.  Two comments: 

1.  We failed to note additional or clarified support for the higher
ratios.  We remain somewhat uncomfortable with characterizing the
science-based support for a ratio of 1:7 as equivalently robust to the
science-based support for standards ranging up to 1:6.  I believe
we’ll pick up the conversation in the morning. 

2.  Questions regarding “reanalysis” and “potentially” on p 4: 

 

More recently, a study of changes in children’s blood Pb levels
associated with reduced Pb emissions and associated air concentrations
near a Pb smelter in Canada (for children through age six in age)
reports a ratio of 1:6 and reanalysis << Did the Agency mean to say
additional analysis ??  Our conversation had not left me with the
impression that the Hilts dataset has been reanalyzed by the Agency >>
of the data by EPA for the initial time period of the study resulted in
a ratio of 1:7 (CD, pp. 3-23 to 3-24; Hilts, 2003). [1]   Ambient air
and blood Pb levels associated with the Hilts (2003) study range from
1.1 to 0.03 µg/m 3 , and associated population mean blood Pb levels
range from 11.5 to 4.7 µg/dL, which are lower than levels associated
with the older studies cited in the 1986 Criteria Document (USEPA,
1986). 

Sources of uncertainty potentially  << The sentence reads well without
“potentially”.  I believe these uncertainties are not potentially
related; they were identified by the author as related >> related to
air-to-blood ratios obtained from Hilts (2003) study have been
identified.   

 

 

Best regards, 

 

heidi 

 

 

 

From: Wegman.Lydia@epamail.epa.gov [mailto:Wegman.Lydia@epamail.epa.gov]


Sent: Wednesday, April 30, 2008 11:25 PM 

To: King, Heidi R.; Fraas, Arthur G. :PersonName

Cc: Crabtree.Tricia@epamail.epa.gov; Martin.Karen@epamail.epa.gov;
Meyers.Robert@epamail.epa.gov; Burnett.Jason@epamail.epa.gov 

Subject: Fw: air-to-blood ratio section 

 

 

-----Forwarded by Lydia Wegman/RTP/USEPA/US on 04/30/2008 11:24PM ----- 

To: Wegman Lydia@EPA 

From: Karen Martin/RTP/USEPA/US 

Date: 04/30/2008 10:28PM 

Subject: air-to-blood ratio section 

Karen Martin, Ph.D. 

Office of Air Quality Planning and Standards 

U.S. EPA (C504-06) 

Research Triangle Park , NC 27711 

phone:  (919) 541-5274 

fax:  (919) 541-0237 

martin.karen@epa.gov 

 

[1] This study considered changes in ambient air Pb levels and
associated blood Pb levels over a five-year period which included
closure of an older Pb smelter and subsequent opening of a newer
facility in 1997 and a temporary (3 month) shutdown of all smelting
activity in the summer of 2001. The author observed that the
air-to-blood ratio for children in the area over the full period was
approximately 1:6. The author noted limitations in the dataset
associated with exposures in the second time period, after the temporary
shutdown of the facility in 2001, including sampling of a different age
group at that time and a shorter time period (3 months) at these lower
ambient air Pb levels prior to collection of blood Pb levels.
Consequently, EPA calculated an alternate air-to-blood Pb ratio based on
consideration for ambient air Pb and blood Pb reductions in the first
time period (after opening of the new facility in 1997).   

