Low level radiation is cancer-protective

.

Two papers:

1) https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1349-7006.1992.tb02342.x

Cancer Mortality Survey in a Spa Area (Misasa, Japan) with a High Radon Background Masaaki Mifune Tomotaka Sobue Hiroko Arimoto Yoshiaki Komoto Sohei Kondo Hiroshi Tanooka First published: January 1992

2) https://www.birpublications.org/doi/full/10.1259/bjr.75.895.750637

BJR > Previous Issues > Volume 75, Issue 895 > Radiation increased the longevity of British radiologists Correspondence Radiation increased the longevity of British radiologists J R Cameron 2678 SW 14th Drive, Gainesville, FL 32608, USA

Research/Patent on Chloroquine treatment against DNA damage

.

"...exposure to chloroquine prior to irradiation increased cell Survival by 30%." 

  US 2005/0014785 A1 

 Authors: 

Michael B. Kastan, Cordova, TN (US); 

Christopher Bakkenist, Cordova, TN (US);

Mark McCamish, Cupertino, CA (US) 

 Pub. Date: Jan. 20, 2005 

 Note: a Patent is not a proof that the invention works! 

 Quotes:

ABSTRACT The present invention provides methods and compositions for the treatment of DNA damage related disorders. One embodiment is a method for the inhibition of Side effects asSociated with chemotherapeutic and radiotherapeutic agents using chloroquine compounds. Another embodiment is a method for treatment and/or prevention of lethal or Sub-lethal radiation toxicities associated with terrorist acts or war.

BRIEF DESCRIPTION OF THE FIGURES 0007 FIG. 1 shows a Kaplan-Meier survival curve of C57/BL6 mice after exposure to 8 Gy total body irradiation (TBI). Half of the cohort received a dose of chloroquine (dashed line) by either i.p. injection (1.75 mg/kg or 3.5 mg/kg) or in their drinking water (3.5 mg/kg or 7 mg/kg) the day before the TBI. The one mouse which died in the chloroquine-treated group received 1.75 mg/kg by i.p. injection.

0008 FIG. 2 shows that chloroquine treatment enhances survival after TBI by enhancing recovery of hematopoietic progenitor cells. Five mice received 3.5 mg/kg chloroquine (C) by i.p. injection 24 and 4 hours prior to TBI (bars with diagonal Stripes). Five mice received no chloroquine (stippled bars). Fourteen days after irradiation, the cellular ity (open bars) of hematopoietic tissues (spleen, thymus, bone marrow) was assessed by a blinded observer on a scale of 0-3 with 3 being normal cellularity. The bars represent the average cellularity of the tissues from the 5 mice in each group.

0009 FIG.3 shows a Kaplan-Meier survival curve of AT mice after exposure to 8 GyTBI. Half of the cohort received a dose of 3.5 mg/kg chloroquine (CHL; dashed line) by i.p. injection 24 and 4 hours prior to the TBI.

0010 FIG. 4 demonstrates that chloroquine treatment prevents the development of tumors in Eul-myc mice. After weaning, a cohort of transgenic mice expressing the c-myc oncogene were started on chloroquine (CHL) at 7.0 mg/kg in the drinking water ((+), solid line). Within 100 days, all of the mice with no drug in the water had died of leukemia, while none of the cohort of mice on drug had Succumbed. The latter group of mice was then divided into two groups (timing of this event depicted by heavy arrow), one group of which was taken off of chloroquine ((-), dashed line) and the other group of which was started on i.p. injections of 3.5 mg/kg of chloroquine once a week. Within a month, all of the mice taken off of chloroquine had developed malignan cies and all of the mice on the weekly i.p. injections remained tumor-free for months.

0011 FIG. 5 illustrates that chloroquine treatment reduces the development of tumors in mice injected with the potent chemical carcinogen, 3-methylcholanthrene (3-MC). Chloroquine (CHL, 3.5 mg/kg) was given by i.p. injection 24 and 4 hours prior to 3-MC injection in 30 mice and 30 mice received the carcinogen with no chloroquine pretreat ment. The percentage of animals remaining tumor-free is plotted. Statistical significance, log rank test P-0.0001.

0012 FIG. 6 demonstrates that chloroquine treatment reduces the development of tumors in mice exposed to ionizing radiation in a protocol that induces thymic lym phomas. Chloroquine (CHL, 3.5 mg/kg) was given by i.p. injection 24 and 4 hours prior to irradiation in four Successive weeks and animals were subsequently observed for the development of tumors. Statistical Significance, log rank test P=0.0012.

0013 FIG. 7 shows tumor incidence in wildtype mice receiving either placebo or CHQ before 3-MC injection. CHQ markedly protects from tumor development.

0014 FIG. 8 shows tumor incidence in ATM-null mice receiving either placebo or CHQ before 3 MC injection. CHQ does not protect from tumor development.

0015 FIG. 9 shows tumor incidence in p53-null mice receiving either placebo or CHQ before 3 MC injection. CHQ does not protect from tumor development.

0016 FIG. 10 demonstrates the efficacy of two chloroquine compounds in preventing, in Varying degree, the change in coat color in mice treated with 8 GY radiation.

------------ Update 14-Aug-2020 -----------------

"Hydroxychloroquine-loaded hollow mesoporous silica nanoparticles for enhanced autophagy inhibition and radiation therapy",by Yan Li et al., 25-June-2020

Dangerous radiation?

.
Interesting article about Manhattan Project scientists contaminated by Plutonium.

The Scientists Who Pee Plutonium

Government conducted live-long study of the 26 contaminated people. Results, quote: "the mortality rate for the group is about 50 per cent lower than the national average."

It appears that up to a certain level of radiation, its effects don't seem to be harmful and it is possible (though not proven) that it may even be beneficial. See also the other posts on the subject.


More quotes:

It may be a surprise to learn that the members of the UPPU club have all done well, especially when compared to national averages. “They’ve fared pretty well as a group,” George Volez and expert on plutonium exposure told Los Alamos Science in 1995. “Of the original 26, only seven have died, and the last death was in 1990.

Update (20/07/2018, thanks @Hokushinsai )

Updated 31/07/2018 (thanks @TuckerGoodrich)

This Giant X-Ray Generator Helped Set Safe Doses for Radiation,
Physicist Lauriston Taylor also found X-rays effective against athlete’s foot and bursitis. By By Evan Ackerman, 28-April-2017

Quote:

“The only single documented whole body exposure that I know that I’ve had was in 1929, and it was measured to be 150 [Roentgen]…. I sat in an X-ray beam for 20 minutes or half an hour or something…. I was just sitting right smack in the beam…. [With that much radiation] you’re supposed to get nauseated, but we didn’t know that in 1929, so I wasn’t.”

For the record, 150 Roentgen is equivalent to 1.4 sievert, which according to this chart starts to put you in the realm of “severe radiation poisoning, in some cases fatal.” But since the chart wasn’t around in 1929, Taylor was just fine. Indeed, he told the interviewer in 1995, “I also used to treat [my] athlete’s foot.... I don’t remember what the dose was, but it was probably four or five hundred R [3.7 to 4.7 Sv].”

“That exposure in addition to medical radiation treatment for bursitis and other benign conditions and from radiation experiments resulted in an estimated whole-body dose-equivalent in excess of a thousand rem [10 Sv],” Taylor’s obituary for the Health Physics Society stated. “He experienced no discernible adverse effect.”

Taylor continued working until the age of 97, and having published over 160 scientific papers and writing or contributing to 24 books, he died in 2004 at the age of 102.

Born during Solar minum - longer lifespan

.
by 5.2 years, on average!  Quite a strong effect and many of the results are statistically significant (p less than 0.05), according to a Norwegian study [1] that analyzed 202 years of data over a population of 8662 people.  See also this article.
A Solar cycle takes 11 years on average, thus the period of the study (1676-1878) spans about 18 cycles.  Interestingly, intensity of cosmic radiation goes down during solar maximum, due to the shielding effect of the active solar wind against Galactic cosmic rays.  Could the lower level of ionizing radiation background present during Solar Maxima [2] have had a detrimental effect, and the higher level during the Solar Minima - may have had a beneficial effect on the newborn babies?  This is my purely speculative interpretation of course - but see my other articles on ionizing radiation!

 Results are shown in the Figures 1,2 and 3, from the referenced paper:

References:

1. "Solar activity at birth predicted infant survival and women's fertility in historical Norway",
Gine Roll Skjærvø, Frode Fossøy, Eivin Røskaft, 
DOI: 10.1098/rspb.2014.2032, Proceedings B of The Royal Society, Published 7 January 2015

2. Cosmic radiation background is strongly and inversely dependent on the Solar activity.  Cosmic radiation is the highest and the Sun is the least active, the Sunspot number is the lowest at Solar Minimum, for example, see the following graph:

The effect is stronger at high latitudes, like in Norway, where the magnetospheric shielding is lower.  Incidentally higher level of Cosmic Radiation during low Solar activity results in high global cloud cover due to cloud seeding, which in turn lowers the global temperature.  This is a stronger effect than due to CO2 variation, according to some studies [to be quoted]. 

Radical news - free radicals are good for us!

Researchers found that free radicals can actually make our cells live longer - read here:

Think antioxidants...

Quote:

... When free radicals interact with the cells, proteins and DNA in the body, they can cause damage by interfering with their chemical structure. Until now, it has been believed that, as a result, we inevitably suffer the ravages of ageing, from normal physical ageing to diseases such as cancer.
But the Canadian study, published in the respected journal Cell, says the opposite. Researchers found that free radicals can make our cells live longer.
This happens by altering a mechanism called apoptosis. This is a process by which damaged cells are instructed to commit suicide in a variety of situations, such as to avoid becoming cancerous when their DNA has mutated dangerously, or to kill off viruses that have invaded the cell.


The scientists have found that free radicals can stimulate this 'suicide mechanism' to do something completely different in healthy cells - bolstering their defences and increasing their lifespan.
Siegfried Hekimi, professor of biology at McGill University, who led the study, says: 'The so-called free-radical theory of ageing is incorrect. We have turned this theory on its head.'
Professor Hekimi says that when he raised levels of free radicals in nematode worms (these simple roundworms are used because their nervous system performs many of the same functions as higher organisms), he got the creatures to live 'a substantially longer life'.
His study reinforces suspicions raised by other scientists. Last year, for example, researchers at the Multimedica Cardiovascular Research Institute in Italy warned that our bodies need the stress caused by free radicals to stimulate them to fight infectious disease and to properly regulate vital bodily functions such as our cardiovascular system.

The Milan-based researchers had surveyed all previous research evidence and concluded in The International Journal of Biochemistry and Cell Biology: 'Increasing the levels of antioxidants in our bodies may harm our health. Balanced levels of antioxidants are important for our cardiovascular system and for healthy ageing.'

The theory behind this idea is called hormesis - which may be more described as 'what doesn't kill you, makes you stronger'.

Scientists believe our bodies have evolved an array of defence mechanisms for surviving tough environments, but that these systems are not switched on unless we are challenged. And that is where free radicals come in.

The problem with antioxidants is that they may neutralise this 'protective' effect. It may also help explain why antioxidant pills have been found to produce some unexpectedly harmful results.
For instance, laboratory studies have shown how high doses of antioxidants such as N-acetyl cysteine - a popular antioxidant supplement - may promote the spread of breast cancer cells.
Meanwhile, the antioxidants beta carotene and vitamin A have been linked to an increased risk of death from lung cancer and lung disease. ...

If supplements make us age faster, then perhaps excessive consumption of vegetables and fruit would make people age faster as well?

Apparently yes!...

Low dose radiation is healthy!

What has cholesterol-heart disease theory and anti nuclear power environmentalism got in common?  It turns out - a lot!      8-:)

I came across a fascinating conference presentation by Philippe Duport on low level radiation in Ottawa University, January 2002.

Basically, turns out that radiation level between 10 to 1000 times stronger than the typical sea level natural background,  reduces the risk of cancer and extends the lifespan!   Some slides:

Note: 0.2Gy (Gray) is 20rad which is a rather high dosage (lethal dose for humans is 100rad), see also Wiki.

30% lung cancer reduction after 0.15Gy dose.

28% longer lifespan in mice at 35 and 70 times the natural background radiation!

Human cancer studies show a similar risk reduction, for example British radiologists have a lesser risk (by about 30%) than their non-radiologist colleagues.  Similar situation with Canadian radiation workers, 12% and 26% lower SIR (Standardized Incidence Ratio) of cancer in women and men, respectively,  28 and 35% lower cancer mortality rate (SMR=Standardized Mortality Rate) in women and men, respectively,  38 and 41% lower all causes mortality rate (SMR=Standardized Mortality Rate) in women and men, respectively (see slides 36,37).  It is interesting to note that the total mortality rate decreases more with (low level) radiation exposure than the cancer mortality, indicating that the protective effect of low level ionizing radiation against many other causes of death (cardiovascular?)  may be even stronger than against cancer!

The next slides illustrates the effect of rising natural radiation level with altitude above the sea level (due to cosmic ray effect).

High elevation = higher radiation = less cancer!

Similar map appears when plotting cancer incidence maps versus natural radiation map due to radon emission from the ground.

More Radon = more radiation = less cancer!

Conclusions (slides 45,46):

• Ionizing radiation is part of life.
• Sources of ionizing radiation are naturally everywhere, in food, air, water and our body.
• Life appeared and evolved in a radioactive environment.
• At environmental levels, there is no evidence of increased risk with increased dose, even when annual doses exceed current dose limits for radiation workers
• In fact, there are indications of decreased risk of cancer and non-malignant diseases at doses and dose rates well above current regulatory limits for the public and the workers.
• Populations in high background areas tend to have less cancers than those in low background areas.
• Low dose radiation is used in medicine: radon spas, cancer treatment and prevention.

This is supported by many other sources, studies and statistics, for example, see Figure 3 at  http://radiation-hormesis.com/

Optimum health = 100 times higher radiation than typ background!

------
Refs:

http://radiation-hormesis.com/

http://www.lowdose.uottawa.ca/projects.htm

http://www.lowdose.uottawa.ca/publications_files/Facts%20about%20low-dose%20radiation%20effects.ppt

http://stan-heretic.blogspot.ca/search?q=hormesis

Low-level ionising radiation protects against cancer!

.

Quote:

The projections of thousands of late cancer deaths based on LNT, are in conflict with observations that in comparison with general population of Russia, a 15% to 30% deficit of solid cancer mortality was found among the Russian emergency workers, and a 5% deficit solid cancer incidence among the population of most contaminated areas.

Paper :   
Observations on the Chernobyl Disaster and LNT. (thanks Peter for pointing it out)

LNT stands for "Linear Non-Threshold" hypothesis that postulates that no matter how low level of radiation, its harmful effects accumulate and add up over time.

This and other papers posted in this blog ( Gamma radiation protects against cancer, in low doses seems to indicate that this theory is dead.
.

Gamma radiation protects against cancer, in low doses?

.
Cancer mortality reduction by 97% - huge!  Is it true?  Hormesis?

Paper:
  "Effects of Cobalt-60 Exposure on Health of Taiwan Residents Suggest New Approach Needed in Radiation Protection",   W.L. Chen et al.,   Dose Response. 2007; 5(1): 63–75, 

Quote:

... serendipitous contamination of 1700 apartments in Taiwan with cobalt-60 (T_1/2 = 5.3 y). This experience indicates that chronic exposure of the whole body to low-dose-rate radiation, even accumulated to a high annual dose, may be beneficial to human health. Approximately 10,000 people occupied these buildings and received an average radiation dose of 0.4 Sv, unknowingly, during a 9-20 year period. They did not suffer a higher incidence of cancer mortality, as the LNT theory would predict. On the contrary, the incidence of cancer deaths in this population was greatly reduced-to about 3 per cent of the incidence of spontaneous cancer death in the general Taiwan public. In addition, the incidence of congenital malformations was also reduced - to about 7 per cent of the incidence in the general public. These observations appear to be compatible with the radiation hormesis model.

   Figure 1 from the same paper.  Click to magnify and hires.

More readings:

1. by D.W.Miller, MD:  Afraid of Radiation

2.  Keeping the Lights On

3. by William R. Ware, Ph.D.:  Low-Dose Radiation Exposure and Risk of Cancer

4. Caroline Hadley: "What doesn’t kill you makes you stronger", Nature, EMBO reports   VOL 4 | NO 10 | 2003

5. Bernard L. Cohen: "Test of linear no threshold theory of radiation carcinogenesis for inhaled radon decay products", University of Pittsburgh 1994

Fig 1a from Cohen's paper 

To annoy anti-nuclear environuts:    Letter... 

More refs added (02-Mar-2011):

6.  Rheumatology 2000;39:894–902;
"Long-term efficacy of radon spa therapy in rheumatoid arthritis—a randomized, sham-controlled study and follow-up"

7. Int.J.Low Radiation,Vol.1,No.4,2005; "Nuclear shipyard worker study (1980–1988): a large cohort exposed to low-dose-rate gamma radiation"

see also John Cameron's (one of the study author) write-up here

Quote:

In 1980, the US Department of Energy (DOE) gave a contract to the School of Public Health at Johns Hopkins University to study radiation risks to nuclear shipyard workers. This study, which extended for more than a decade, cost the taxpayers $10 million. This was the World's best epidemiological study of nuclear workers. The study has yet to be published more than 12 years after its completion in early 1988.
...
The reader may think that the nuclear shipyard study is contradicted by other human studies. I know of no contradictory studies. One other radiation worker study--the British radiologists study. (Smith and Doll 1981)-- also looked at the death rate from all causes. It gives results consistent with NSWS. (Table 2.)

.