On
8/8/2004, Gerald Cairnes posted:
am amazed that mercury should be in any systemic medicine these days.
Apparently used as a preservative in 5 in 1 vaccine for
infants??????????????????????
http://news.bbc.co.uk/go/em/-/1/hi/health/3544674.stm
Peter
Macinnis replied:
My recollection is that the amount
of mercury used is very small indeed, and that this is a very old claim.
John Winckle responded:
It was compared to the amount of mercury in half a tuna sandwich, (that
is in all the child vaccinations combined) but you have to eat the half
sandwich over five years.
Gerald
cairnes answered:
I did not check the quantities or
the story, however I don't believe it to be an appropriate material to
be used in such a fashion - there are some things you just don't do
whatever the background levels and they are a bloody sight higher than
they ought to be by our own hand.
Jim Edwards added:
I would never even feed tuna to my cat since I was told by a vet that
most tuna comes from Thailand where there is mercury pollution in the
ocean and that it accumulates as it goes up the marine food chain to
the tuna at the
top.
Paul
Williams commented:
Thought that these sites may be of
interest:
"Vaccines listed in the Australian
Vaccination Schedule for Children have not contained thiomersal [an
orgonomercurial] since 2000. All childhood vaccine stock in circulation
is thiomersal free."
http://www.vaccination.org.au/questions/question2111.html
There doesn't appear to be any
conclusive evidence that trace amounts of thiomersal are harmful.
Nevertheless, it appears that possible neurological damage is plausible
and a general movement away from this preservative is now being
actively encouraged:
Daya Papalkar responded:
I am not sure why thiomersal is being used in this vaccine in the UK.
As a preservative in vaccines, it has been used for many years, but as
Paul has stated, there is a trend to removing it. This is apparently on
the basis of minimising exposure to mercury rather than there being
known adverse outcomes due to thiomersal levels used in vaccines. Not
using thiomersal is obviously a good thing in terms of preventing
*potential* for adverse
outcomes.
In Western countries, a very important issue is the perception of
safety of the vaccine, not just the actual safety. Even though the
mercury levels used in vaccines were below the accepted exposure
limits, it is ammunition for
the anti-vaccination lobby. So removing thiomersal may be an important
public health issue more in terms of vaccination rates/acceptibility
rather than mercury toxicity (in Western countries).
As I have previously stated, IMO, in general, people are not good at
calculating & comparing risks when the odds of the adverse events
are very low. This is particularly true with vaccination, because many
parents have no experience of the actual disease that is being
vaccinated against.
In developing countries, thiomersal is used in multiple use vaccine
vials. The risk/benefit/cost analysis there is very different.
Removing thiomersal may be prohibitively expensive for these countries
(changing to single use
vials), and if that means lower vaccination rates, then that is a
potentially far more hazardous outcome than giving small amounts of
mercury with the vaccine.
The BBC article that Gerald referenced was alarmist & somewhat
unbalanced. I think it is actually important for the media to remind
people of the success of vaccination in preventing disease - it is too
often portrayed as an
impost of government. The article did not mention that the live
attenuated polio vaccine is far more effective at preventing polio than
the killed vaccine. We can't assume that changing back to the old
vaccine will not result in more cases of polio.
Gerald
Cairnes replied to Daya:
I
was not being alarmist when I referred to this article, not that you
suggested I was being alarmist, but the mere use of metals like mercury
and cadmium in what I suspect is an unnecessary application is not good
policy. I can't offer any alternative preservative suggestions in this
area - I have been too long away from matters biological. If it is not
necessary then don't use it these things have a habit of coming back to
bite you.
I
see unnecessary applications of these metals all around us and must
question why it is we still persist in spite of all of the so called
proscriptions against them. Some time ago car manufacturers switched
from brass welch plugs to cadmium plated steel plugs. I presume on a
basis of cost. The result was that the cadmium was electrolytically
removed in service or at the first time the engine was flushed with the
cadmium trapped between the plug and the block setting up a
differential current that rapidly corroded through the plugs. Brass or
copper has none of these problems as they are far more easily corrosion
protected chemically and do not represent a real problem in terms of
pollution so why change, they can last a lifetime? They have ceased
this practise I understand but it is a decision that should never have
been made in the first place.
Another
such application of cadmium is the plating on screws and bolts that
again could be just as easily plated with passivated copper and present
a risk many orders of magnitude lower than cadmium. I received a
request from a client through an agent to comment on why fungal growth
was occurring all over the Colourbond roofing except directly above the
underlying purlins. Looking at the image it appears to be associated
with a zone of inhibition around each roofing screw and the
adjacent zones have merged to produce the longitudinal zone
illustrated. The longitudinal effect is well defined and there may be
another explanation or compounding process at work here. Regardless if
this is the correct interpretation it is an interesting effect and if I
am correct then it is a good visual demonstration of why cadmium should
not be used in these applications as it is dispersing into the
environment in significant amounts over large areas to accumulate in
the food chain. So many of these inappropriate substances are used
because they happen to be low cost waste products from other processes.
and
to Paul:
It
is not only a question of the toxicity of mercury per se, now where did
I put my course of BAL, it is also the question of the toxicity of
thiomersal (50% mercury approx) itself ending with the residual effects
of mercury accumulation. I am not being alarmist simply making the
point that although I do not have any immediate alternative suggestions
I feel sure we can do better than this. As someone has already noted
background levels may be low but this varies wisely from place to place
bio- accumulation is an issue.
A
quick Google will bring up some PDF's on the subject.
It
is the same type of situation that we encountered recently with a
certain government department who did not want to know so they shot the
messenger and claimed I had a conflict of interest. Bullshit, they had
not done the most fundamental of tests before choosing their material
and the hands over arse syndrome took over at various levels. In this
case there is a very serious public safety issue that could have been
resolved quietly and sensibly in the public interest practically and
financially, so now instead they have the publicity they did not want.
It's called a whitewash!
Will
the person who has nicked my BAL please return it quick, now I know why
I have only two neurones left and I need them, so who do I sue. :-)
