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See the following reference. It reports the amount of mercury released from dental amalgam is minimal; a person would have to have 490 amalgam surfaces for there to be enough mercury vapour and ionic mercury given off from amalgam fillings to meet the maximum exposure guidelines. Exposure or absorption and the crucial question of limits for mercury. ARTICLE SOURCE: J Can Dent Assoc (Canada), Jan 1999, 65(1) p42-6 ABSTRACT: Health Canada recently lowered the recommended maximum daily exposure of mercury from all sources for women of child-bearing age and for children less than 10 years. This new exposure guideline does not seem to be based on any new scientific finding of human toxicity. The average daily intake of methylmercury (mainly from fish) that may cause demonstrable health effects in the most sensitive individual is 300 micrograms/day, or 4.3 micrograms Hg/day/kg body weight. The new, lower Health Canada limit is 95% below the level that may cause health effects. A number of studies have looked at methylmercury in human breast milk (where maternal consumption of fish is high), but no strong evidence of toxicity has been reported. The amount of mercury released from dental amalgam is minimal; a person would have to have 490 amalgam surfaces for there to be enough mercury vapour and ionic mercury given off from amalgam fillings to meet the maximum exposure guidelines. The uptake of food-related organic mercury is six times higher than the uptake of mercury from amalgam; moreover, food-related mercury is significantly more toxic. Many studies of amalgam-related mercury are flawed by confusion between exposure and absorption for the various forms of mercury, a limited selection of data, the ignoring of confounding variables or the misclassification of data. Uttam Garg, PhD, DABCC Associate Professor Director of Clinical Chem & Tox Labs Children's Mercy Hospital Kansas City, MO 64108 Phone: 816-234-3803 Fax: 816-234-3794 > -----Original Message----- > From: Les Culank [SMTP:[log in to unmask]] > Sent: Wednesday, May 28, 2003 5:18 AM > To: [log in to unmask] > Subject: Re: Mercury Level and dental amalgam > > Dear Nick, > > Thanks for the references. With Pubmed, I've tried to get my teeth (& > fillings) further into this literature. > > But I must apologise that in spite of your kind help, I still don't > empathise with a mercury-amalgam aetiology for a claimed clinical > toxicity. > > Seeking up-to-date human Hg stuff, plus ready access to full papers, I > note > for work by the first 3 groups you quoted (I can't find the 4th paper): > Jones MM nearly all non-human rat studies > Daunderer M lots of papers on toxicology but nearly all non-Hg > Aposhian HV Many human studies on metals toxicity, ± chelation > > You may also be interested to see two recent human/Hg references by Vamnes > et al (the first I got in full PDF): > Vamnes JS, Eide R, Isrenn R, Hol PJ, Gjerdet NR Blood mercury following > DMPS administration to subjects with and without dental amalgam. > Sci Total Environ 2003 Jun 1;308(1-3):63-71 > > Vamnes JS, Eide R, Isrenn R, Hol PJ, Gjerdet NR. Diagnostic value of a > chelating agent in patients with symptoms allegedly caused by amalgam > fillings. J Dent Res 2000;79:868 874. > > > Sorry about my perseveration that the "quackwatch" url (a long way below) > really is well worth a quiet read in full. > > Best wishes, > les > > > > > From: "Nick Miller" <[log in to unmask]> > > > > > Les, > > > > No, I don't think you are going to find any prospective double-blinded > > control trials to support my assertions. People are either happy with > their > > mercury fillings or want to get rid of them, and you can't ethically > select > > half of the people who may be suffering from leaking dental amalgam and > > mercury sensitivity and say "we are not going to treat you". > > > > The "black propaganda" put about on this topic doesn't help either. Many > > people have mercury amalgam fillings and suffer no apparent ill effect, > but > > a certain number (in my non-double blinded uncontrolled > experience)suffer > > very serious consequences. They obviously don't go for help to > practitioners > > who tell them they are delusional (or that there isn't enough in the > > literature on this). Perhaps labs don't have the expertise, > instrumentation, > > or indeed time, to do urine mercury measurements before and after a > > challenge test but I don't think that justifies a hectoring and > aggressive > > approach to what is a very real problem. > > > > Sooner or later dentists will stop using mercury (as many already have) > and > > the problem will resolve itself. > > > > > > References are: > > > > 1. Jones MM New developments in therapeutic chelating agents as > antidotes > > for metal poisoning. Crit Revs in Toxicol 1991;21:209-233. > > > > 2. Daunderer M. Moblisation test for environmental metal poisoning. > Forum > > des Praktischen und Allgemenden-Arztes 1989;28:88. > > > > 3. Aposhian HV, Bruce DC, Alter W, Dart RC, Hurlbut KM, Aposhian MM. > > Urinary mercury after administration of DMPS: correlation with dental > > amalgam score. FASEB J 1992;6:2472-2476. > > > > 4. Hibberd AR, Howard MA, Hunnisett AG. Mercury from dental amalgam > > fillings: studies on oral chelating agents for assessing and reducing > > mercury burdens in humans. J Nutr Environ Med 1998;8:219-231. > > > > > > Nick Miller, > > > > London > > > > > Dear Nick, > > > > What is your evaluation of the "Evidence" for this? Any chance of such > a > > thing as a prospective double-blind CT? I would very much appreciate a > > reference to anything helpful, if you have one handy. > > > > Many thanks, > > > > Les > > > >> From: Nicholas Miller <[log in to unmask]> > m > >> > >> Yes, belief in the non-toxicity of dental amalgam is strictly for those > >> without much knowledge of physical chemistry - even if dentists have > been > >> using it for many years. > >> > >> The finding that there is no hazard is based on not looking for mercury > in > >> body fluids in an appropriate way. Blood mercury is usually normal, > except > >> where you have industrial exposure. But excess mercury can often be > >> demonstrated from leaking fillings by means of a challenge test with a > >> chelating agent, measuring the rise in urine mercury. > >> > >> Nick Miller, > >> > >> London > >> > > >> From: Gareth Morgan <[log in to unmask]> > > >> > >>> "There is also DoH advice that there is no evidence of harm" > >>> > >>> I seem to remember that once upon a time there was no problem with BSE > in > >>> meat from British cattle.................................. > >>> > >>> > >>> At 16:40 2003-05-22 +0100, Les Culank wrote: > >>>> Try this: > http://www.quackwatch.org/01QuackeryRelatedTopics/mercury.html > >>>> > >>>> There is also DoH advice that there is no evidence of harm, but to be > >>>> ultra-cautious they suggest it is only during Pregnancy to go easy on > > the > >>>> dental work. > >>>> > >>>> Best wishes, > >>>> > >>>> Les > >>>> > >>>> > >>>> > >>>> > >>>> > >>>> > >>>>> From: Peter Auld <[log in to unmask]> > > >>>>> > >>>>> Hi all > >>>>> > >>>>> Can anyone help with a query from one of our GPs who has a patient > > anxious > >>>>> about mercury poisoning from her dental fillings to the point of > > arranging > >>>>> to have her amalgam fillings removed. Prior to this she wants her > > mercury > >>>>> levels documented. Is this possible or worthwhile? > >>>>> > >>>>> Any ideas would be appreciated. > >>>>> > >>>>> Regards > >>>>> > >>>>> Peter Auld > >>>> > > > >>> Med vänliga hälsningar/With best regards > >>> > >>> Gareth > >>> > >>> Take a look at http://www.vardforbundet.se/ifbls2004 > >>> > >>> http://www.ki.se/biomedlab > >>> e-mail [log in to unmask] > >>> > >>> Tel +46 8 5858 1038 > >>> Fax +46 8 5858 7730 > >>> > >>> Gareth Morgan MPhil MSc FIBMS, > >>> Department of Laboratory Medicine (Labmed), > >>> Karolinska Institutet, > >>> Huddinge Universitetssjukhus, F46 > >>> SE 141 86 Stockholm > >>> Sweden > >>> > >>> OBS! Besöksadress: F-Huset, Forskningsgatan 2 F52, Rum 2.10. > Laboratoriet > >>> för klinisk patologi och cytologi. > >>> > >>> NB! Visiting address: Building F, Research Corridor 2 F52, Room 2.10. > >>> Clinical Histo- and Cytopathology Laboratory. > > ------ACB discussion List Information-------- > This is an open discussion list for the academic and clinical > community working in clinical biochemistry. > Please note, archived messages are public and can be viewed > via the internet. Views expressed are those of the individual and > they are responsible for all message content. > > ACB Web Site > http://www.acb.org.uk > List Archives > http://www.jiscmail.ac.uk/lists/ACB-CLIN-CHEM-GEN.html > List Instructions (How to leave etc.) > http://www.jiscmail.ac.uk/ ------ACB discussion List Information-------- This is an open discussion list for the academic and clinical community working in clinical biochemistry. Please note, archived messages are public and can be viewed via the internet. Views expressed are those of the individual and they are responsible for all message content. 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