Reply #8: comments on the other study; also unethical, ridiculous study [View All]

[philb]

Comments on
"Neurological and Renal Effects of Dental Amalgam in Children", D.C. Bellingor et al, JAMA, April 10, 2006

I agree with others that the study design was not a serious effort to determine amalgam safety. But the authors
interpretation of results is also questionable.

It is known from thousands of studies and millions of tests by medical labs that those with amalgam get
significantly higher mercury exposure than those without, that mercury accumulates in the brain and major organs
proportionately to the number of amalgam fillings, and commonly causes chronic degenerative neurological conditions later in life. http://www.home.earthlink.net/~berniew1/indexa.html
Thus the ethics in the exposure to a group of children to higher levels of a very neurotoxic substance such as mercury is highly questionable.

This study was not a serious test of the safety of amalgam since the exposure was to children with no previous amalgam fillings at relatively low levels of exposure for a very limited period of time. The mean number of restored amalgam surfaces in the mouth of the amalgam group at the end of the study was only 4 amalgam surfaces. And while the urine mercury level in the amalgam group was 50% higher than the non-amalgam group, this is a much lower differential than most studies of groups or either children or adults with and without amalgams.

However, even with the low exposure levels, it is not clear from the study results that there were no significant adverse effects of amalgam shown as claimed by the authors.

For example, it is well documented that mercury from amalgam commonly causes chronic neurological conditions in adults. So it might be useful to compare diagnosed neurological conditions between amalgam and non-amalgam group. The comparison is as follows:

Condition amalgam group non-amalgam group percent difference
migraines 18 14 28.5%
neurological illness 4 1 300%
psychological disorders 24 18 33%
sensory disorders 36 28 28.5%
----------------------------------------------------------------------------------------------------
Total 82 51 60%

Amalgam is also known to cause respiratory problems- the study found the following
Asthma 19 17 13%
Respiratory disorders 13 7 86%
--------------------------------------------------------------------------------------------
Total 32 24 33%

Similarly while the authors state that there were no significant renal effects observed, it could be noted that
the unadjusted mean albumin level at year 5 for the amalgam group was 38% higher than for the non-amalgam group. I would be very concerned about the future of some at the high end of the amalgam group albumin levels.


the same comments about the other study also apply to this one