1

Summary Minutes of the

U.S. Environmental Protection Agency

Clean Air Scientific Advisory Committee (CASAC)

Public Teleconference

May 8, 2013

1:00pm – 3:00pm

CASAC Members: Dr. Christopher Frey, Chair

Dr. Ron Wyzga

Dr. Kathleen Weathers

Dr. Helen Suh

Dr. Jack Harkema

Mr. George Allen

Dr. Ana Diez-Roux

Purpose: To review draft letters on EPA’s Integrated Science Assessment for Lead 

(Third External Review Draft – November 2012) and EPA’s Policy Assessment for the 

Review of the Lead National Ambient Air Quality Standards (External Review Draft –

January 2013).

Designated Federal Officer: Dr. Holly Stallworth, Designated Federal Officer

 

Other EPA Staff: Aaron Yeow, Rachel House, Suril Mehta, Meredith Pedde, 

Marion Hoyer, David Orlin, John Vandenberg, Mary Ross, Erin Hines, Lisa VinikoorImler, Meredith Lassiter, David Svendsgaard, Elizabeth Owens, Ellen Kirrane, Molini 

Patel, Dennis Kotchmar, Jennifer Richmond-Bryant, Kevin Cavendar, Diedre Murphy

Public: Linda Wilson (New York Attorney General’s Office), Roger Miksad

(Battery Council International), Chris Knight (Inside EPA), John Howes (Redland 

Energy), Tony Roberts (Nevada Division of Environmental Protection)

Meeting Materials and Meeting Webpage: 

The materials listed below may be found on the meeting webpage at: 

http://yosemite.epa.gov/sab/sabproduct.nsf/bf498bd32a1c7fdf85257242006dd6cb/c8927b

033cbedfdb85257b1d00671864!OpenDocument&Date=2013-05-08

• Agenda

• Federal Register Notice 

• Public Comments from RSR Corporation and Kennecott Utah Copper 

LLC. 

• Draft Reports: 

o 04-22-13 Draft CASAC Review of the EPA’s Integrated Science 

Assessment for Lead (Third External Review Draft – November 2012)
2

o 04-22-13 Draft CASAC Review of the EPA’s Policy Assessment for 

the Review of the Lead National Ambient Air Quality Standards 

(January 2013 Draft)

Meeting Summary

The discussion followed the plan presented in the meeting agenda. 

WEDNESDAY, MAY 8, 2013

Dr. Stallworth convened the meeting and explained that CASAC operates under the 

Federal Advisory Committee Act. She also noted that all CASAC members were in 

compliance with conflict of interest and federal ethics rules. She then asked Dr. Helen 

Suh to chair the review of the draft letters since Dr. Christopher Frey had chaired the 

CASAC Lead Review Panel. There was one public commenter, Mr. Gerard Manley of 

RSR Corporation, who presented oral comments (posted at the meeting webpage at the 

URL above) that stressed the need for greater protection for exposed children than 

provided by the 2008 Lead (Pb) NAAQS.

Dr. Suh asked Dr. Frey to summarize the Integrated Science Assessment (ISA) letter and 

Dr. Frey walked members through the letter. 

With respect to the ISA letter, CASAC members discussed the language for 

acknowledging there will be no further review of the ISA while asking EPA to consider 

the recommendations from CASAC. 

CASAC discussed the causal determination for low level Pb exposure and renal 

dysfunction and Dr. Frey explained that panelists felt strongly enough about that 

recommendation (that the relationship was “suggestive of a causal relationship” rather 

than “likely to be causal”) to put it in the letter to the Administrator. By comparison, 

CASAC had less disagreement with EPA’s causal determination for the relationship 

between Pb exposure and attention-related behavioral problems. In response to a 

question from a CASAC member, Dr. John Vandenberg of EPA’s National Center for 

Environmental Assessment noted that EPA had already “downgraded” the causal 

determination for renal dysfunction from “causal” to “likely causal” in going from the 2nd

draft to the 3rd draft. 

One member asked for a change in the sentence referring to “relative magnitude of risk 

factors” to distinguish between effect modification versus increased exposure. Members 

agreed to revise the language to refer to the extent to which risk factors modify the effect 

of Pb exposure. Members agreed to make this revision in response to Question 6 on 

Potentially At-Risk Populations as well. 

CASAC members turned their attention to the Policy Assessment (PA) letter. Dr. Frey 

summarized the letter and pointed out that CASAC was not expecting to review a 2nd
3

draft PA. One member stressed the need to distinguish between whether there is new 

information or whether new information exists but it is not sufficient to justify changing 

the standard. Dr. Frey explained that there is new literature but it doesn’t make forward 

progress on reducing data gaps and uncertainty on the relationship between air Pb levels 

and blood concentrations. Members agreed to specify the remaining data gaps and 

research needs in the letter.

Dr. Frey explained that the Lead Review Panel wanted EPA to provide more context for 

Pb exposure, specifically that Pb exposure from air emissions were a small fraction of 

human exposure. Moreover, exposure pathways through outdoor soil and indoor dust in 

response to legacy Pb were more important in determining blood Pb levels. 

Again a member asked for a distinction to be made between whether there was no 

information or whether new information exists but was not sufficient to justify lowering 

the standard. Members debated whether it was contradictory to say there is no scientific 

evidence of a threshold on the one hand, while still recommending retention of the 

current Pb standard. Dr. Frey referred to the choice of standard as a policy issue when 

there is no evidence of a threshold. Moreover, he said information was not available to 

assess air to blood level relationships at the current standard, making it difficult to assess 

the adequacy of the current standard. 

Members agreed to delete language referring to risk communication and the setting of a 

standard based on implicit acceptance of a 1 - 2 point loss of IQ.

Mr. Aaron Yeow, Designated Federal Officer for the Lead Review Panel, said he would 

work with Dr. Frey to make final edits to the letters. Since some members expressed a 

desire to review the letters after these revisions, Mr. Yeow said he would send out the 

revised letters to the full CASAC for their final concurrence. 

On Behalf of the Committee, 

Respectfully Submitted, 

Holly Stallworth, Ph.D. /s/

Designated Federal Officer

Certified as True: 

Christopher Frey, Ph.D.. /s/

Chair, Clean Air Scientific Advisory Committee

NOTE AND DISCLAIMER: The minutes of this public meeting reflect diverse ideas and suggestions 

offered by committee members during the course of deliberations within the meeting. Such ideas, 

suggestions, and deliberations do not necessarily reflect definitive consensus advice from the panel 

members. The reader is cautioned to not rely on the minutes represent final, approved, consensus advice 

and recommendations offered to the Agency. Such advice and recommendations may be found in the final 
4

advisories, commentaries, letters, or reports prepared and transmitted to the EPA Administrator following 

the public meetings