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From the international Amalgam Mailing list :

IV. Health Effects from Dental Personnel Exposure to Mercury Vapor 1. Dentists and dental personnel who work with amalgam are chronically exposed to mercuryvapor. (1,6-12,32,34,36,72,122,123,124,171,172,173,240,249] Studies note that carpeting in dental offices should be avoided as it is a major repository of mercury[188]. Mercury levels in urine of dental personnel average about 2 times that of controls(123,124,171,249) and was 43 nmol/liter for a population surveyed in Sweden(171), which is above the Swedish occupational exposure guideline. 2. Drilling old amalgam fillings with only a saliva extractor and no other precautions produces mercury vapor levels 2 to 15 times occupational threshold limit values(30 micrograms/cubic meter)[120,219]. 3. The average dental office exposure affects the body mercury level approximately the same as having 19 amalgam fillings[123,124,173]. Dentists were found to score significantly worse than a comparable control group on neurobevaioral tests of motor speed, visual scanning, visuomotor coordination, concentration, verbal memory, visual memory, and visuomotor coordination speed(249). 4. Both dental hygienists and patients get high doses of mercury vapor when dental hygienists polish or use ultrasonic scalers on amalgam surfaces(240). Pregnant women or pregnant hygienist especially should avoid these practices during pregnancy or while nursing since maternal mercury exposure has been shown to affect the fetus and to be related to birth defects, SIDS, etc. (38,61) and breast milk contains up to 6 times higher mercury than in the mother's blood(20). 5. Body burden increases with time and older dentists have median mercury urine levels about 4 times those of controls, as well as higher brain and body burdens(13,34, 70-74,122]. Some older dentists have mercury levels in some parts of the brain as much as 80 times higher than normal levels(14,34). 6. Dentists and dental personnel experience significantly higher levels of neurological, memory, musculoskeletal, mood, and behavioral problems, which increase with years of exposure(13,34,49, 69-74,88,122,188,246,247,248,249]. 7. Female dental technicians who work with amalgam have significantly reduced fertility and lowered probability of conception(3,24,38, 121], and their children have significantly lower average IQ compared to the general population(13). The level of mercury excreted in urine is significantly higher for female dental assistants than dentists(171,172,173,247). Several dental assistants have been diagnosed with mercury toxicity and some have died of related health effects(245,246,247,248). 8. Many homes of dentists have been found to have high levels of mercury contamination used by dentists bringing it home on shoes and clothes[187]. 9. Some studies have found increased risk of lung, kidney, brain, and CNS system cancers among dental workers(14,34, 143]. 10. Autopsies of former dental staff found levels of mercury in the pituitary gland averaged over 10 times that of controls(99), as well as higher levels in the occipital cortex and renal cortex and thyroid. References 1. Sandra Denton MD; Proceedings of the First International Conference on Biocompatibility, 1988 3. Gordon - Pregnancy in Female Dentists- a Mercury Hazard. Proceedings of Intl conference on Mercury Hazards in Dental Practice Sept. 2-4 Glasgow 1981 6 Schulein,T.M.; Reinhardt, J.W. and Chan K.C. Survey of Des Moines area dental offices for Mercury vapour. Iowa Dent. J. 70(1):35-36 1984 7 JonesDW, Sutton EJ, and Milner EL Survey of Mercury vapour in dental offices in Atlantic Canada.Can. Dent. Assoc. J. 4906:378-395, 1983 8.Miller RW and Ochua;. Report on independant survey taken of Austin dental offices for mercury contamination. Texas Dent. J. 100(1):6-9, 1983 9 Kantor,L. and Woodcock C, Mercury vapour in the dental office- does carpeting make a difference? JADA103(9):402-407,1981 10 Skuba, A. Survey for Mercury vapour in Manitoba dental offices J Can. Dent.Assoc. 50(7):517-522, 1984 11 Chop GF. and Kaufman EG. Mercury vapour related to manipulation of amalgam and to floor surfaces.Oper. Dent. 8(1):23-27,1983 12 RoydhouseRH. FergMR . and Knox RP. Mercury in dental offices J Can Dent Assoc 51(2):156-158, 1985 13 Butler J. Proceedings from the First International Conference of Biocompatibility. 1988 14 Magnus Nylander, Mercury Concentrations in the human brain and kidneys in relaton to exposure from dental amalgam fillings ICBM 1988 20 Vimy,MJ,Takahashi,Y, Lorscheider,FL Maternal -Fetal Distribution of Mercury Released From Dental Amalgam Fillings. Dept of Medicine and Medical Physiology , faculty of Medicine, Univ of Calgary, Calgary Alberta Cannada 24 BrodskyJB. Occupational exposure to Mercury in dentistry and pregnancy outcome. JADA111(11):779-780., 1985 32 Jonnes, Suttow and Milner. Survey of Mercury vapour in dental offices in Atlantic Canada, Canadian Dental Association Journal ., 49(6):378-395.,1983 34. Patrick Störtebecker, Associate Professor of Neurology, Karolinska Institute , Stockholm.. Mercury Poisoning from Dental amalgam- a hazard to the human brain. Bio-Probe, Inc. ISBN: 0-941011001-1 & Neurology for Barefoot Doctors, Stortebecker Foundation for Research, 1988. 35 Hal Huggins. Its All in Your Head, 1994. 36 Sam Queen; Chronic Mercury Toxicity: New Hope Against an Endemic Disease. Bio-Probe Books 38 Ziff S. and Ziff M. Infertility and Birth Defects: Is Mercury from Dental Fillings a Hidden Cause?, Bio-Probe, Inc. ISBN: 0-941011-03-8.1987 49 Amalgam Hazards - an assesment of research By Irwin Mandel DDS Assoc. Dean for Research School of dental and Oral Surgery Columbia University New York Published JADA Vol. 122 August 1991 61 Dr Gustav Drasch, Institute of Forensic Medicine, University of Munich. Public anouncement, 25 January 1994 Bio Probe March 1994; & "Mercury burden of human fetal and infant tissues", Euro.J. Pediatrics,153(8): Spring 1994, p607-610. (69)D Gonzalez-Ramirez et al; "Uninary mercury, porphyrins, and neurobehavioral changes of dental workers in Monterrey, Mexico", J Pharmocology and Experimental Therapeutics,, 272(1): 264-274,1995 (70) N.J. Heyer et al, "Behavioral Effects of Low Level Exposure to HgO Among Dentists", Neurotoxicology & Teratology; 17(2):161-168(1995). (71)S.C.Foo et al, "Neurobehavioral effects in Occupational Chemical Exposure",Environmental Research, 60(2): 267-273, 1993. (72)D.L.Smith,"Mental effects of mercury poisoning",South Med J 71:904-5,1978. (73)RT McNerney et al, "Mercury Contamination in the Dental Office: A Review", NYS Dental Journal, Nov 1979, p457-458. (74) D.G. Mantyla et al, "Mercury toxicity in the dental office: a neglected problem", JADA, 92:1189-1194, 1976. 88) M.Godfrey et al, Confirmation of mercury retention and toxicity using DMPS", J Advance Med 7(1):19-30, 1994. (99) M.Nylander et al, Mercury accumulation in tissues drom dental staff and controls", Swedish Dental Journal, 13:235-243, 1989. (120) L.Pohl, "The dentist's exposure to elemental mercury during clinical work", Acta Odontol Scand,v53,n1,p44-48,1995. (121)A.S.Rowland et al,"The Effect of Occupational Exposure to mercury vapor on the fertility of female dental assistants",Occup Environ Med, v55,n1,1994