How to estimate risk of stochastic effects mainly cancer for a given population exposed to low doses (5-10) mGy per year prevalent in High Background Radiation Areas without using the concept of collective dose as well as ICRP's accepted risk factor of ~5%/Sv?
Calculation of risk requires an information triad of scenario, consequence, and probability. Your scenario is High Background Radiation (HBG) and the consequence is cancer. What you need is the probability of cancer with a good description of the scenario. A necessary piece of the scenario is the expected cancer rate under similar conditions except HBG.
The probability of cancer under your scenario cannot be assessed without data or a working hypothesis. The hypothesis is subject to verification. There are proposed alternatives to the ICRP risk probabilities: threshold, linear-quadratic, DDRF, hormedic, ...
Data can be used from one or more HBG to propose a chronic low-dose rate risk.
Collective dose has been largely discounted. You might try an approach as in the attached.
If you want to use the ICRP risk coefficient you'll need the doses to be in the form of effective dose. Is the 5-10 mGy for a specific organ or body part, or an average whole body absorbed dose?
@Alvarez, Thanks-Sir, get back in case of additional query after reading the attached article.
@Harbron; the doses prescribed in question are average whole body absorbed doses from photons, so all organ doses are also practically equal to whole body dose. Please note that calculations are to be made without using ICRP's number.
For residents in several high background radiation areas, there have been reports with risk estimates.
For instance, the following paper has reported excess relative risk/Gy (ERR/Gy) for solid cancer (-0.13 Gy-1). Then, how to use this number for 5-10 mGy depends on your model, but given a linear dose response relationship, it becomes -0.0013 at 5 mGy.
https://www.ncbi.nlm.nih.gov/pubmed/19066487
If you wish to estimate risks based on data from various populations in different high background radiation areas, you may conduct its meta-analysis.
Even if you do not wish to use ICRP's detriment adjusted nominal risk coefficients of 5.5%/Sv for whole population and 4.1% for adults, the approaches used by ICRP to calculate such risks will be useful. To this end, you may look at A.4.4 of ICRP Publication 103, and section 4 of the attached paper.
Article Quantitative assessment of provability of radiation-related ...
@Hamada Sir
Thanks for excellent references and reply. Get back to you after in depth study of the literature.
Remember that these different populations have different life styles that contribute differently to the probability of cancer, aside from radiation exposure.
Different lifestyles in different populations would indeed be important.
ERR in each study is obtained after consideration of various lifestyle factors and other confounders, but the background incidence of disease varies among countries and also within the country.
You may be interested in the ongoing work of ICRP Task Group 102 "Detriment Calculation Methodology".
http://www.icrp.org/icrp_group.asp?id=95
This is a new task group established in March 2016 and had the first face to face meeting in October 2016.
The process of detriment calculation is under review, and will be documented in a reproducible manner, considering ways in which different approaches might be applied when new data become available.
For this, discussion is ongoing, and an update will be posted here on ResearchGate timely.
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