In the 50’s and 60’s there was a campaign to collect baby teeth from people around the St. Louis area driven by local doctors, scientists and teachers:
“The idea for the study was hatched in the mid-1950s during the build up of the Cold War. By then, the U.S. and Soviet Union had tested hundreds of nuclear weapons. Prevailing winds carried the radioactive debris from the U.S. tests, many of which were conducted in the desert regions of the West, to St. Louis and farther east.” [stl today article]
Using Grant Money these scientists decided to do the science:
“Funded by the U.S. Public Health Service and Leukemia Society of Missouri and Illinois, it entailed volunteers visiting schools, churches and PTA meetings, churches, libraries and dental clinics distributing registration forms. Parents mailed in their children’s baby teeth and information cards with names, addresses, birthdates and other information.” [stl today article]
The St. Louis study collected baby teeth from locals in the St. Louis area. Based on the results of sampling those teeth authorities and some of the general public realized that strontium, cesium and other contaminates were falling from the sky and getting into our food supply. People were drinking contaminated milk. What the study found was frightening:
“The study found that children born in St. Louis at the height of the Cold War in 1963 had 50 times as much strontium 90, a radioactive isotope found in bomb fallout and at nuclear reactors, in their teeth as children born in 1950 — before most of the atomic tests. Results ultimately contributed to the signing of an international treaty to ban atmospheric nuclear weapons testing.” [stl today article]
The concern that contributed to the Nuclear Test Ban Treaty should have led to efforts to end the use of nuclear energy worldwide. What the study showed was frightening,…
but the news was contained. The teeth had been sampled, but many remained in boxes. They wound up in a storage room. To be rediscovered later.
“85,000 baby teeth in shoeboxes in an ammunition bunker at Washington University’s Tyson Research Center. The teeth, packaged in small envelopes, were among those collected in the 1950s and ’60s but never analyzed for radioactive strontium.”
This has led to a follow up, epidemiological study found even more frightening data about the results of exposure to radiation.
“They were given to the Radiation and Public Health Project, which set out to advance the findings of the original study by looking at health effects on people who had elevated strontium 90 levels in their teeth as children.” [stl today article]
What they found was a correlation between baby tooth radiation levels and later cancers and mortality.
“In 2010, Mangano and Janette Sherman published a study in the International Journal of Health Services. It concluded men who grew up in the St. Louis area in the early 1960s and died of cancer by middle age had more than twice as much strontium 90 in their baby teeth as men born in the same time and area who were still living.”
Dealing with objections to the study
Of course people working in the nuclear industry jumped to defend themselves. When mainstream media published this story they usually interview Nuclear Power spokespersons who will say things like the study “confuses correlation with causation.” But we already have evidence that radioactive substances cause mutations. That mutations cause cancers. We have that from the lab. Simple deduction shows that If a person is exposed to radiation (even small amounts) there will be mutations. Given there are mutations there will be cancers.
Correlation establishes Evidence of Causation
The next objection is that a healthy immune system will deal with most mutated cells and incipient cancers. The body normally uses Killer T Cells to “order” the mutated cells to self destruct. It takes an accumulation of mutations and specific cancer generating processes for cancer to develop. So merely being exposed to cancer causing substances doesn’t mean that a particular mutagen caused a particular cancer. But laboratory evidence also shows that radiation impacts the immune system too. In severely radiated people they don’t die directly from radiation in some cases but from leukemias, cancers and Radiation induced Acquired Immune Deficiency (AIDS). So again the causation can be deduced from laboratory evidence and simple logic.
Now whether these effects are non-linear or linear is a matter for argument. I personally believe that the numbers will suggest non-linearity (Chaotic rather than purely random or simply determined). Non linearity suggests that there are probably thresholds beyond which odds start rising exponentially, but also suggests that normal curves don’t apply and that risk never falls to zero. In any case most of the arguments you hear from the officials are deceptive, simplistic and deliberately misleading. So I don’t believe the authors really believe what they are saying themselves. And the results of the Survey described in the book “Radioactive Baby Teeth Cancer Link” support that theory.
Therefore in this case correlation verifies causation.
Most of these scientists and technicians base their arguments on the notion that there is a threshold below which mutagen exposure is harmless. This is based on a much criticized study from the 1950’s, but it still gets cited. Anyway, the book “Radioactive Baby Teeth the Cancer Link” goes into detail on this:
- Book At Amazon:
- Radioactive Baby Teeth, Book
- Further reading:
- Example of arguments on the “linear no threshold” argument.