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Re: MCLS, VOCs, Child Cancer, and Sustainablilty



Ralph,
Is there any MCL and or MCLGs based on a dose basis and population factor
that specifically is based on a child's weight and consumption patterns?

Children do consume more water then adults, and they are more vulnerable to
carcinogens aren't they?

Cheers,
Donald Sutherland
Member of the Society of Environmental Journalists


-----Original Message-----
From: Ralph Cooper <cooperre@flash.net>
To: Donald Sutherland <donaldsutherland-iso14000@worldnet.att.net>;
p2tech@great-lakes.net <p2tech@great-lakes.net>
Date: Friday, September 10, 1999 1:54 PM
Subject: Re: MCLS, VOCs, Child Cancer, and Sustainablilty


>I think Donald's comment misses entirely the point of the memo to which he
>is responding.  The point is, if there is data of a particular health
effect
>that is sufficiently reliable to use in making a risk assessment, then that
>risk assessment and that health effect is used in setting the MCL and/or
>MCLG.
>
>Once upon a time, long ago and not so far away, the assumptions underlying
>the setting of the MCLs and MCLGs were based on a lifetime consumption of 2
>L per day, and DOSES were estimated based on a 70 kg adult.  We also used
to
>use a 10,000 population factor.  Now we use a different dose basis and a
>higher population factor, at least 1,000,000.  That means that that if the
>risk assessment shows one additional death per 1,000,000 at the
extrapolated
>dose, then the MCL is set at or below that level.
>
>All of the above are based on linear or log-linear extrapolations from data
>based on much higher doses.  The assumptions underlying that kind of
>extrapolation are too numerous and too subject to question to be discussed
>herein.
>
>Ralph
>Ralph E. Cooper, Ph.D., J.D.
>14139 Woodstream
>San Antonio, TX 78231
>210-479-5490 (4)
>cooperre@flash.net
>
>-----Original Message-----
>From: Donald Sutherland <donaldsutherland-iso14000@worldnet.att.net>
>To: p2tech@great-lakes.net <p2tech@great-lakes.net>
>Date: Friday, September 10, 1999 12:40 PM
>Subject: MCLS, VOCs, Child Cancer, and Sustainablilty
>
>
>>
>>9/7/99
>>
>>Robert,
>>If cancer is the number one killer of children in this country,
>>and child cancer is on the rise according to the National Cancer Institute
>>(NCI),
>>and volatile organic compounds (VOCs) in drinking water can cause cancer
in
>>children according to the EPA,
>>then establishing a MCL for VOCs in drinking water to protect children
from
>>cancer risk without using a Risk Estimate modeled on a child's weight and
>>consumption patterns is without regard to the safety of this
subpopulation.
>>
>>Particularly since child cancer is acute and on the rise.
>>
>>
>>Shouldn't protecting children with MCLs for VOCs specifically designed
with
>>the risks associated with that subpopulation be the starting point for
>>protecting the health of the nation?
>>
>>Donald Sutherland
>>Member of the Society of Environmental Journalists
>>donaldsutherland-iso14000@worldnet.att.net
>>
>>
>>-----Original Message-----
>>From: Robert A. Michaels <76517.747@compuserve.com>
>>Date: Wednesday, September 08, 1999 10:16 AM
>>Subject: Re: MCLS, VOCs, and USDW
>>
>>
>>Folks,
>>
>>        As a health risk assessor, I have worked on preparing drinking
>>water criteria documents at a consulting firm under contract to support US
>>EPA promulgation of drinking water standards under the Safe Drinking Water
>>Act.  I can say that the idea that MCLs are promulgated without regard to
>>their safety to sensitive subpopulations, most notably infants and
pregnant
>>women, is unbalanced and incorrect.  A more correct concept is that MCLs
>>may compromise stringency to establish standards attainable in practice in
>>the near term, whereas MCLGs (Maximum Contaminant Level Goals) are more
>>stringent, though they may be attainable only with long-range planning.
>>Indeed, zero MCLGs for carcinogens may be unattainable ever, but
>>approachable.
>>
>>        Concern expressed about MCL protectiveness to infants seems to
have
>>arisen from EPA use of the (once) standard assumption of a 70-kg adult
>>drinking 2 L of water each day.  Consider, however, that infants often are
>>breast-fed.  When not breast-fed, they typically consume commercially
>>prepared formula, which may come ready-to-consume, or may require dilution
>>with local water (or, more to the point, the local water is diluted with
>>formula before consumption).  Finally, although the MCL may be expressed
as
>>a substance concentration in drinking water, that concentration typically
>>was derived based upon internal doses attained in studies involving
animals
>>and/or humans; including studies of reproductive, fetotoxic, and
>>teratogenic effects; as may have been available.  One of these effects may
>>or may not represent the 'critical' effect which formed the reported basis
>>for MCL derivation for a specific substance, but if the reported basis was
>>different, that does not mean that reproductive, fetotoxic, and
teratogenic
>>effects were unconsidered in deriving the MCL.
>>
>>        In my view, the bottom line is that drinking water standards may
be
>>imperfect.  Some individual MCLs might be found to be inadequate, and
>>perhaps should be revisited, especially in light of emerging research.
>>However, in my experience MCLs do not wantonly disregard the need to
>>protect infants, pregnant women, and other sensitive subpopulations.
>>
>>===============================
>>Robert A. Michaels, PhD, CEP
>>President
>>RAM TRAC Corporation
>>3100 Rosendale Road
>>Schenectady, NY  12309-1510
>>(518) 785-0976 (voice)
>>(518) 785-0976 (telecopier)
>>76517.747@compuserve.com
>>===============================
>>
>>
>