LEAD - PETROL LEAD IN THE ENVIRONMENT AND ITS CONTRIBUTION TO HUMAN-BLOOD LEAD LEVELS

Since the 1960s it appears that overall lead exposure, as measured by lead in blood, is decreasing in many countries. A number of factors are responsible, such as: increased awareness of the toxic effects of lead and its widespread occurrence in the environment; phasing out the lead in solder; care in the removal of lead paint; replacement of lead water pipes; and, in some countries, reduction of the amount of lead in petrol. While these useful gains have been made, two debates have raged on. The first is on the significance of the contribution that petrol lead makes to lead exposure, and the second is on the level of lead exposure that produces 'sub-clinical' impairment of neuropsychologic functioning in children. The first debate is the subject of this review. But the discussion also comments first on the natural levels of lead, and on the routes by which humans are exposed to lead. Refs.