Vegetative function diagnosis for early detection of lead intoxication.

In the search for the early effects of neurotoxic lead poisoning, vegetative function diagnosis is a potential approach, focusing on the behaviour of the cardiac rhythm. Four groups of male subjects (109 copper workers exhibiting mean lead levels in blood of 31.2 micrograms/dl after long-term lead exposure; 27 control subjects having a similar job in the iron and steel industry without neurotoxic exposure; 35 reference subjects from Magdeburg University Hospital without neurotoxic exposure, and 5 subjects to whom benefits have been awarded for disability resulting from lead intoxication) were studied. All subjects underwent the same psychometric test battery. Special attention was paid to the restoration of vegetative tone after exposure. The more extensive the exposure to lead, the longer was the delay in restoration. This effect seems to be reversible, as workers heavily exposed to lead, but otherwise healthy, were more affected than the patients included in this investigation. Simply comparing the cardiac rhythm of exposed and non-exposed subjects at rest is not sufficient for early detection of lead intoxication. The behaviour of cardiac rhythm in humans at rest is the result of long-term influence by a wide range of factors, of which lead exposure is only one.