AW: [ RadSafe ] DNA Damage and Oxydative Processes

[Rainer.Facius at dlr.de]

John:
 

>From BEIR VII-Phase2, Prepublication Copy Uncorrected Proofs, p.294-295:

 

"Lundell and others (1996) reported more specifically on the risk of breast cancer among women from this cohort. The mean absorbed dose to the breast was 0.39 Gy (range <0.01, 35.8 Gy). 75 breast cancer cases were found in the cohort during the follow-up period. A significant linear dose-response relationship was observed, with an ERR of 0.38 per Gy (95% CI 0.09, 0.85) and an EAR of 0.41 per 10^4 PY/Gy. This was not modified by age at exposure or by dose to the ovaries. The ERR increased significantly with time since exposure, however, with an ERR at one Gy of 2.25 (95% CI 0.59, 5.62) 50 years or more after exposure. The EAR was 22.9 per 10^4 PY/Gy." 

 

<...> p.295-296:

"Pooled analyses of the data on breast cancer and the intracranial tumors from the two Swedish hemangioma cohorts were also carried out. In the pooled breast cancer analyses (Lundell and others 1999), 245 breast cancer cases diagnosed between 1958 and 1993 were available. The ERR was estimated to be 0.35 per Gy (95% CI 0.18,0.59) and the EAR 0.72/10^4PY/Gy (95% CI 0.39, 1.14). There was no evidence of an effect of time since exposure on the ERR; the EAR, however, increased with time since exposure. Neither age at exposure, dose-rate, or ovarian dose appeared to have an effect on the ERR." 

 

Given the data - in contrast to the imposed fit parameters - and the focus on exposures say below 1 Gy, I consider this account by BEIR VII a blatant misrepresentation of the hemangioma findings, unless of course you 'know' the LNT postulate to be true.

 

Given the following evaluation on page 331, I am totally at a loss to grasp their later account of the Cardis 1995 findings:

 

"Studies of populations with occupational radiation exposures are of relevance for radiation protection in that most workers have received protracted low-level exposures (a type of exposure of considerable importance for radiation protection of the public and of workers). Further, studies of some occupationally-exposed groups, particularly in the nuclear industry, are well suited for the DIRECT ESTIMATION [my capitals] of the effects of low doses and dose rates of ionizing radiation (Cardis and others 2000)."

 

In table 8-7, p.357, they report - apart from their half-hearted comments on p.356 without any cue what the data(!) really show - an ERR per Gy of 2.2 (0.1,5.7) as a relevant estimate of the leukemia-excluding-CLL risk for low doses and dose rates. It is really hard to belief.

 

If you find pertinent qualifications regarding these studies, please let us know.

 

Regards, Rainer


________________________________

Von: John Jacobus [mailto:crispy_bird at yahoo.com]
Gesendet: Sa 09.07.2005 00:29
An: jjcohen at prodigy.net; Facius, Rainer; goldinem at songs.sce.com; radsafe at radlab.nl
Betreff: Re: [ RadSafe ] DNA Damage and Oxydative Processes



Of course, you have read the BEIR VII report.  Right?

--- jjcohen at prodigy.net wrote:

> This is an excellent demonstration of BEIR's  bias
> --- showing that by
> sufficiently torturing any data set, one can get it
> to yield any desired
> conclusion.
>