Mercury Toxicity Archives

Neuropsychological assessment of a practicing dentist

Neuropsychological assessment of a practicing dentist with elevated urinary mercury. Fundamental and Applied Toxicology, Supplement:The Toxicologist, 15, 1, March, 1995.

Website: www.neurotox.com
E-mail: raysinger@aol.com

NEUROPSYCHOLOGICAL ASSESSMENT OF A PRACTICING DENTIST WITH ELEVATED URINARY MERCURY. R. Singer. Santa Fe, New Mexico, USA

Dentists are exposed to mercury from amalgam (composed of 52% mercury, 8% copper, 37% silver) used as implants for dental restoration. A recent study of 32% of Singapore's dentists found mercury dose-related neuropsychological deficits when compared with controls.

The current subject, a dentist practicing for 14 years in the USA, was referred by his physician for neurobehavioral examination. The subject presented with symptoms including fatigue, GI problems, sweats, tremors, rashes, bowel dyscontrol, and heart arrhythmia. Tremors of the hand and eyelid affect the subject's hand stability while working.

Results of the Neurotoxicity Screening Survey showed a profile of symptoms consistent with neurotoxicity. Urine sampling (24 h) over the past year found 2.1 - 99 ppb mercury, averaging 35 ppb (expected range < 2 ppb; atomic fluorescence spectrometry). High readings may be related with chelation therapy.

Current IQ was at the 87% (% = percentile; 91-96% or greater estimated pre-morbidly), consistent with his presentation as an intelligent, competent dentist. In contrast to a relatively high IQ, appropriate neuropsychological testing revealed that the subject has deficits in immediate memory (16%); visuospatial perception (50%); visual memory; visual figure-ground perception (50%); verbal learning (2-5%); mental flexibility (12%); attentional processes (19%); logical memory (p < .004); and non-verbal recognition memory (50%). Neuropsychological testing helped confirm mercury toxicity affecting multiple organ systems. Such deficits impact the subject's ability to practice dentistry, and raises questions as to effects of mercury in other dentists, as well as possible subclinical or clinical effects among the estimated 80-90% of Americans with mercury amalgam implants.

Re: Neuropsychological assessment of a practicing dentist (Archive in mercury.)