Hello,

please see here: http://www.sciencedirect.com/science/article/pii/S1438463916301109

Thanks a lot Dr. Amal for your comment. But I am asking about the safety levels of uranium in blood not for the Canadian subjects only.

Best Regards   

 Your question is confusing. Are you looking for safe levels, reference levels, or standard values? You intend to compare uranium levels in smokers and non-smokers. What you need is the level in your control group of non-smokers. The level of uranium in blood or urine varies within a population. You cannot predict the range in any given population. The uranium concentration within a population from a given region can show a very broad range. The variation is from diet and water source. A worker population at a USA laboratory had two distinct background ranges. The ranges were traced to two different water supplies.

Thanks a lot Dr. Joseph for your comment my question is about the reference value of uranium content in the blood. International Commission on Radiological Protection (ICRP), reported that the reference value of uranium in urine is 0.5 μg/l. Therefore we need to know the reference value of uranium content in blood.  

Best Regards  

The ICRP reference level is for emergency or unexpected exposure. None is given for blood. It is unclear how you plan to use a reference level. Your project is Uranium Concentrations in Biological Samples of Smokers. You do not appear to need a reference level. 

Note: The fraction of uranium in blood that is excrete in urine is 0.67. See internal dosimetry models.

The level of uranium in blood varies within a population and region. You cannot predict the range in any given population.I think there is no save level of U in blood.

Variability of Uranium content in normal whole human blood is large ( two order of magnitude ) and is attributed to age, sex, diet and environmental influence on the investigated population as well as to the analitical method.

You may find in the attached refferences some results dealing with uranium concentrations in human blood in different countries (including your country)  

http://www.tandfonline.com/doi/abs/10.1080/01422448408209683?journalCode=grad19

http://www.sciencedirect.com/science/article/pii/004896979190256E

https://link.springer.com/article/10.1007%2Fs10967-012-2114-2?LI=true

http://journals.lww.com/health-physics/Abstract/1993/09000/Normal_Concentration_and_Excretion_Ratio_of.9.aspx

Thank you Dr. Florian Glodeanu for your comment and good notes.