In the first two samples that we sent to the lab in the fall of 2011, no Strontium 90 was detected. The lab could only tell us the levels were below their relatively high detection levels of 0.2 Bq/l.
It is possible that in the fall of 2011, the cows had not started eating the post Fukushima 2011 hay crop. As well, it takes a while for the Strontium 90 to bio-accumulate up the food chain.
It is unfortunate that the detection level for the lab was so high at 0.2 Bq/l. As noted earlier, Health Canada’s lab was able to detect Strontium 90 at lower levels of detection (0.0176 Bq/l). Their equipment is clearly much more sensitive than the equipment at the lab we hired – a whopping 1,136% more sensitive!
Our testing lab’s equipment was not sensitive enough to detect the very small amounts of some radioactive fallout isotopes that can present a health issue, particularly in regards to children, and pregnant women.
If we had had a lab that was able to detect Strontium 90 at the levels possible in the Health Canada lab, we may have detected Strontium 90 in our milk earlier.
Nevertheless, by January 2012 our lab detected Strontium 90 at 0.3 Bq/l. By February 2012 the level detected had risen to 0.4 Bq/l.
In September 2012, we sent another sample of our milk to the same lab that had previously tested for and detected the Strontium 90. We received a call from the lab telling us that they had had an “explosion” because of the processing – get this – of our milk samples. They would no longer test our milk for Strontium 90.
We had to search for a different lab. We tried two other labs, not happy that their standards may be different or that we probably would not be able to compare results with those already obtained. Subsequent results from milk samples sent to the new labs in May 2012 and October 2012 showed that they were not able to detect Strontium 90 in our milk even though their detection levels were lower than those of our first lab.
We are not sure if the new labs are as good as the old one. Strontium 90 is difficult to detect. Possibly the new labs didn’t have the same ability to detect the Strontium as our original lab. Possibly the last two milk samples were from milk of a different dairy that may not have had any localized fallout. Six samples in 12 months is not enough to definitely say anything other than we know Strontium 90 was detected in the milk and we need to encourage the government to do regular testing.
It costs $400 to test each milk sample. Only the government has the kind of money needed to test our milk weekly.
Standards and “Acceptable Limits”
Canadian and American Standards for what levels of radionuclides are considered safe are quite different. The EPA Maximum Contamination level for Strontium 90 is 8 pCi/l which converts to 0.29 Bq/l The Canadian Standard is much much higher at 5 Bq/l.
Canada has an even higher level of “action” following a nuclear emergency. According to the “Canadian Guidelines for the Restriction of Radioactively Contaminated Food and Water Following a Nuclear Emergency”, the action level from Strontium 90 is 30 Bq/l.
Thirty becquerels is the same as 810 pCi/l – over 100 times higher than the EPA Maximum Contamination Level. Does the Canadian government think that human beings can handle more radiation just because there has been an nuclear emergency?
But government standards of what is “acceptable” really have nothing to do with the issue. We always ask ourselves “acceptable” to whom”?
No matter what standard the governments use, it’s important to know that there is NO safe level of radioactivity. In 2006, the National Academy of Sciences’ National Research Council’s Committee to assess Health Risks from Exposure to Low Levels of Ionizing Radiation approved the Linear No-Threshold (LNT) model says that radiation is always considered harmful and has no “safety threshold.”
This means that when there is no radiation, there is no health risk. As soon as there is any radiation at all, no matter how small, there becomes a risk to health. There is no level low enough that will not increase the risk of cancer. As the level of radiation increases, so does the risk.
As well, the sum of several very small exposures are considered to have the same effect as one larger exposure.
It is clear that by January 2012, the level of Stronium 90 in our local milk, 0.3 Bq/l or 8.1 pCi/l had surpassed the U.S.’s EPA Maximum Contamination Level (MCL).
By February 2012, the level was even higher at 0.4 Bq/l (10.8 pCi/l) which meant it was 35 % over the EPA MCL.
In an email communication with the head of the National Monitoring Bureau of the Radiation Protection Bureau at Health Canada, when he was asked if Health Canada indeed stopped testing British Columbia milk for Strontium 90 on May 22, 2012 or had there been more tests, he replied:
“No more tests have been done or are planned. We are ready to resume testing if we have any reasons to believe Sr-90 might be a problem in BC milks.”
We believe our test results will give Health Canada a reason to restart testing British Columbia milk. We have sent them our results and we are awaiting their reply.
We have written to them with our results and asked them if these results are enough reason for them to resume testing. We can only hope that a future article by Team EnviroReporter will announce a resumption of government testing.
To be sure, though, we are not holding our breath.
What Strontium 90 does to the body
Strontium 90 never occurs naturally. It is man-made by the nuclear fission reaction. Strontium 90 is a “bone seeker.” It mimics calcium and if a bone is deficient in calcium, it will take up Strontium 90 in place of the calcium.
But whereas calcium will make your bones strong, Strontium 90 gets deposited in the bones and bone marrow and causes bone cancer and cancer of the tissues nearby. It can also get into the blood and cause leukemia.
Strontium 90 decays by practically pure beta radiation. When beta particles are ingested, they penetrate cells at the molecular level and are so strong that they can actually change the structure of the molecules they strike. If the molecule it strikes is a DNA molecule, then it can cause a spontaneous mutation.
Babies and pregnant women are the most sensitive to the effects of radiation. If a pregnant woman is drinking milk that has radioactive Strontium 90 in it, the fetus will concentrate that radioactivity. If a woman who is breastfeeding is drinking radioactive milk, the Strontium 90 will concentrate in her breast milk and thus get transferred to her baby.
Young children are the next most affected. Young girls are more affected than young boys. Women are more susceptible to the effects of radiation than men.
Strontium 90 has a half life of 28.79 years so it will be around for about 290 years before it completely decays away to a nonradioactive and risk-free form. That is, any Strontium 90 you ingest and lodges in your bones will remain in your body, decaying away, for your entire life.
There is no question about it – Strontium 90 is a man-made poison that we should never have to consume.
What do the levels mean?
The highest level we found in our lab tests post-Fukushima was 0.4 Bq/l .
0.4 Bq/l sounds like such a small number doesn’t it? Consider for a minute that one becquerel (bq) is one disintegration every second. One becquerel is defined as the activity of a quantity of radioactive material in which one nucleus decays every second.
Thus, when we say that radioactive Strontium 90 decays, we mean that its nucleus decays or disintegrates. As mentioned earlier, Strontium 90 decays by beta radiation and you have already read how damaging this type of decay is.