A neuropsychological study of children with elevated dentine lead level: Assessment of the effect of lead in different socio-economic groups

Lessons from a Danish Study on Neuropsychological Impairment Related to Lead Exposure

“…In this regard, the situation in Aarhus municipality may differ in a fortunate way from other settings, e.g., the U.S., where increased lead exposure is likely to occur in delapidated inner-city neighborhoods (18). In addition, we found that the effects of lead on neurobehavioral performance were similar in all socioeconomic strata of the case-control group (4).…”

“…Not surprisingly, the lead concentration in the tooth as a whole correlates poorly with the level in circumpulpal dentin, the average lead concentration ofthe latter being about five times greater (6). That the lead concentration in dentin is an important predictor is stressed by the fact that two ofthe studies that showed the most marked lead-related decreases in neurobehavioral performance (4,13) were based on dentin measurements.…”

“…Several neurobehavioral tests were employed to determine the character and extent ofpossible neurobehavioral dysfunction (4). The verbal Wechster Intelligence Scale for Children (WISC) and the Bender gestalt test, as scored by the Gottingen system, showed significantly decreased performance in the children in the high dentin-lead group ( Table 2).…”

“…Within this cohort, we selected a nested case-referent group of 200 children who were examined in detail (4 Accordingiy, epidemiological studies in lead neurotoxicity have used parameters indicating lead absorption, primarily the lead concentration in blood and/or teeth (1-3). We chose to determine the lead content ofcircumpulpal (or secondary) dentin from shed deciduous incisors (5,6).…”

Behavioral effects of lead: commonalities between experimental and epidemiologic data.

“…In contrast to the result of IQ measures, performance on the Wisconsin Card Sort Test was associated with blood levels at 57 months and 10 years but not earlier (48). In the Danish study, Hansen et al (39) reported that tooth lead was a better predictor of intellectual function, while concurrent blood lead levels were a better predictor of psychomotor speed in firstgrade children. Since tooth lead levels reveal average past exposure but not the detailed pattern, more precise statements cannot be made regarding the pattern of lead body burden and its relation to performance on various tests.…”