Document ID: EPA-HQ-OPP-2007-0388-0030
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2007-08-13T04:00Z

Additional Information/Clarification  

on the August 14/15 Scientific Advisory Panel Dietary Session’s Charge
Question 3

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Charge Question 3: Bayer Drinking Water Consumption Survey Data

The CSFII data does not contain information on the time and amounts of

direct drinking water consumption. Bayer CropScience sponsored a study,

Drinking Water Consumption Survey (DWCS) that was designed to obtain

a distribution of water intake for a 24-hour time period from a

representative sample of the US population. Participants recorded their

water consumption (time of day and amount consumed) over a one-week

(7 consecutive day) period. The authors, Barraj et.al. (2004), suggested

that it may be possible to “allocate the total daily water consumption

amount reported in the CSFII into various drinking occasions” using

information from the DWCS. In addition to offering a fixed option for

allocating direct drinking water throughout the day, the Agency is
planning

to include in SHEDS-Multimedia v. 4 the option to allocate direct
drinking

water consumption throughout the day through empirical use of the Bayer

DWCS data.

Please comment on the advantages and disadvantages of providing

an option to use the Bayer DWCS data in SHEDS-Multimedia v. 4.

Please include in your comments any statistical concerns or issues

associated with the design and conduct of the DWCS study.

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EPA considers the dietary session of this SAP meeting to be a
consultation on a variety of disparate topics rather than a formal
review. We have not provided the Panel with working dietary software,
nor have asked the Panel for a formal review of the dietary code.  As
such, we offer the following clarification to Charge Question 3:  

EPA Clarification of Charge Question 3:   EPA recognizes that it has
provided each of the Panel members with only background information on
the Bayer DWCS as part of the document “An Update on the Development
of the SHEDS-Dietary Model”  and has not provided Panel members with
the Bayer submission itself.  The intended purpose of the above charge
question was less to receive specific comments on the conduct and
analysis of the Bayer DWCS, but rather to introduce this as a possible
source of data  and obtain the Panel’s thoughts and ideas on the
conceptual utility of this kind of study, in principle.    More
specifically, we are looking for advice from the Panel on ways studies
conducted in this way could be interpreted and potentially used and any
suggestions the Panel might have on ways data collected in this manner
should be examined and interpreted. EPA has, to date, only performed
exploratory analysis of the data provided by Bayer and has not yet
formally reviewed this submission or used it as part of a regulatory
decision.  EPA will use the thoughts and ideas presented by the Panel in
its discussion of this topic and, if warranted at a later date, may
present the study and our analysis to the Panel, along with our proposed
use of the study as an available option in the SHEDS model.