Re: New Multiple Myeloma Study

["Ron L. Kathren" <rkathren@tricity.wsu.edu>]

Jer --

Good question.   The answer depends on many factors, including one's own
tolerance for risk, and the specific conditions.  For example, if you need
heart surgery to survive and/or enjoy a good quality of life, you may be
willing to undertake a surgical risk of death of several per cent (and I can
speak from experience here).  On the other hand, this level of risk is
clearly unacceptable if one is taking a vacation trip to an exotic location.

What is an 'appropriate level of risk' for many human endeavors is
established by governmental bodies; thus government mandates air bags in
automobiles, has an extensive drug testing and approval via the FDA, has
immunization clinics in local health departments, restricts access to areas
considered dangerous in National Parks, and so on.  Many times a formal risk
analysis is not done.

Now presumably your question was referenced to radiation risks.  Both ICRP
and NCRP have answered it, as have the various Federal regulatory bodies.
My own choice of an 'appropriate level of risk' from radiation (nonmedical)
would again depend on the circumstances.  However, I have published as de
minimis values 10E-6 per year for members of the general public and 10E-4
for radiation workers.  Note that these are de minimis values, and therefore
imply that a higher level of risk may be warranted depending on
circumstances.

Hope all is well with you, good friend; if you will be in Denver we can
discuss this in much more depth over a latte and I'll even let you buy!

Warm regards,

Ron
----- Original Message -----
From: Jerry Cohen <jjcohen@prodigy.net>
To: Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
Sent: Tuesday, April 11, 2000 8:26 AM
Subject: Re: New Multiple Myeloma Study


> Ron,
>     What is  "an appropriate level of safety."?
>
> JJcohen@ prodigy.net
>
> -----Original Message-----
> From: Ron L. Kathren <rkathren@tricity.wsu.edu>
> To: Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
> Date: Monday, April 10, 2000 10:58 PM
> Subject: New Multiple Myeloma Study
>
>
> >While I make no brief for or against the "new" multiple myeloma study by
> >Wing et al., since I have not read it, it might be instructive to look at
> >the already published literature with respect to radiation and multiple
> >myeloma.   Gilbert was not the only one who saw an apparent association
> >between multiple myeloma and low level irradiation.  BEIR V (pp. 327
ff.),
> >citing Cuzik, notes that such an increase in multiple myeloma was
observed
> >in 12 of 17 irradiated populations, with an overall O/E of 2.25 (50 cases
> >observed to 22.2 expected).  NCRP Report 121, published 5 years after
BEIR
> >V, tabulates no less than 42 studies (Table 3.4, pp. 35-36) with various
> >populations and exposures (including those cited by Cuzik, except where
> >later analyses were available for the same populations) coming up with an
> >observed:expected ratio of 1.17 for the combined studies (503 cases
> >observed; 431 expected).  Somewhat more than half of the studies showed
an
> >O/E ratio > 1, with by far the largest ratios (5.2, 5.7, 6.2) occurring
in
> >the three studies of Thorotrast patients.  If these three relatively
small
> >Thorotrast studies are excluded, the O/E ratio changes only slightly, to
> >1.14, 491:429.   Interestingly, the 42 studies tabulated in NCRP 121 did
> not
> >include the 1979 paper by Gilbert cited by Otto Raabe but instead
included
> a
> >later (1993) publication regarding the Hanford cohort which showed no
> excess
> >of multiple myeloma (O/E = 0.9, 25 cases observed vs. 27.4 expected) but
> did
> >show a marginally positive slope dose -response.
> >
> >While the Wing et al. study may (and likely does) have its problems, I
> think
> >there are enough data from earlier studies to reasonably conclude (or at
> >least strongly suggest) that there is likely an association between low
> dose
> >irradiation and multiple myeloma.  Whether this is age dependent remains
to
> >be seen.  But in any case, my first impression is that the Wing et al.
> study
> >does not appear to be too far afield from what has been observed in a
> number
> >of other studies.  According to the local newspaper reporter who just
> >called, Wing et al. have apparently indicated that based on their study
the
> >exposure limits should be reduced.   Whether or not the recommended
> exposure
> >limits should be lowered on the basis of the study by Wing et al. is at
> this
> >point an interesting speculation, but it is just that -- speculation that
> >begs additional study to verify that the existing limits provide an
> >appropriate level of safety.
> >
> >Ron Kathren
> >
> >
> >
> >
> >
> >
> >----- Original Message -----
> >From: Otto G. Raabe <ograabe@ucdavis.edu>
> >To: Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
> >Sent: Monday, April 10, 2000 3:33 PM
> >Subject: Re: New Multiple Myeloma Study
> >
> >
> >> April 10, 2000
> >> Davis, CA
> >>
> >> Steve Wing's UNC study of 4 labs was discussed in RadSafe in detail in
> >> 1998. Here is a copy of one of the messages I sent in February, 1998:
> >> *****************************************
> >>
> >> February 3, 1998
> >> Davis, CA
> >>
> >> Dear All:
> >>
> >> Yesterday Steve Epperson posted the abstract of a new study by Steve
Wing
> >> about risks to radiation workers. Dr. Wing is an epidemiologist at
North
> >> Carolina who personally believes that the nuclear industry is evil.
> >>
> >> In the 1970's it was noted by Gilbert et al. (Rad. Res. 79:122-128,
1979)
> >> that there was an apparent association of some extra cases of multiple
> >> myeloma among radiation workers at Hanford. This was considered a
random
> >> observation, since it was not found in other studies. Also, remember
that
> >> if you look at every possible type of cancer, ignore those that are
lower
> >> in exposed groups, and look only for those that are elevated, it is
> >> possible that you will find at least one type of cancer that seems to
be
> >> associated with radiation exposure. That observation is expected by
pure
> >> chance. Then if you ignore everything else, you could claim that this
> >> random observation proves that radiation is responsible even at the low
> >> levels of exposure received by radiation workers. This the the method
> used
> >> by some epidemilogists who really want something to report.
> >>
> >> Okay. What Wing did was get money from NIOSH to study myeloma cases at
> >> Hanford but incorporating data from other laboratories including LANL,
> >ORNL
> >> and SRS. In his abstract he notes that there also were confounding
> >> exposures of the radiation workers to many other agents "including
> >> solvents, metals, welding fumes, asbestos,....and non-ionizing
> radiation."
> >> However, only exposures to ionizing radiation were quantified well
enough
> >> for him to include in his analysis!
> >>
> >> This was a case control study where all the cases of myeloma deaths
were
> >> matched with control persons who lived to the same age, but did not
> >develop
> >> myeloma. When radiation exposure was considered he found: "Total
> >cumulative
> >> radiation doses were similar between cases and controls." NO RADIATION
> >> EFFECT! Well, that wasn't the right answer, so now he started
subdividing
> >> the data and found that if he only considered people whose exposures
> >> occurred at ages 45 or older, there was a significant association of
risk
> >> of myeloma with radiation exposure after age 45 "adjusted for age,
race,
> >> sex, facility, period of hire, birth cohort, monitoring for internal
> >> radionuclide contamination, and external radiation received prior to
age
> >> 45." This observation is the whole basis of his report. He reports an
> >> increased incidence of a factor of 4.3 for workers receiving doses
> greater
> >> than 5 rem. [Review of the A-bomb survivor data shows a dose of above
100
> >> rem delivered instantaneously was required to yield this large an
> increase
> >> in multiple myeloma cases and simultaneously yielded about a seven-fold
> >> increase in leukemia cases (BEIR V).]
> >>
> >> Wing claims that increased cancer sensitivity in older workers is
> expected
> >> theoretically and found in some other studies. Actually, my reading of
> >BEIR
> >> V shows a consistent reduction in risk of radiation induced cancer of
all
> >> types with increased age at exposure! Also, if this is a radiation
effect
> >> rather than a chance observation, we would expect that other cancer
types
> >> would be more readily observed, such as leukemia and lung cancer, but
> >> apparently not.
> >>
> >> Wing's results show no overall effect until selectively grouped to
> achieve
> >> an observed level of significance. You can guess that he tried every
> >> conceivable combination of age grouping to harvest a significant
> >> observation from the study so that he could declare that his "findings
> and
> >> other studies of nuclear workers have implications for radiation
> >protection
> >> standards for workers and the general public."
> >>
> >> Finally, the observations by Wing that there is no overall effect, but
> one
> >> remarkably appears when considering exposures of people older than 45,
> >> suggests that there must be a protective effect for exposures that
occur
> >at
> >> ages younger than 45. This is because overall he found that: "Total
> >> cumulative radiation doses were similar between cases and controls." NO
> >NET
> >> EFFECT!
> >>
> >> Otto
> >>
> >> *****************************************************
> >> Prof. Otto G. Raabe, Ph.D., CHP
> >>               Institute of Toxicology & Environmental Health (ITEH)
> >>    (Street address: Building 3792, Old Davis Road)
> >> University of California, Davis, CA 95616
> >> Phone: 530-752-7754  FAX: 530-758-6140
> >> E-mail ograabe@ucdavis.edu
> >>               *****************************************************
> >>
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> >
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