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

Abstract

Serious problems emerge when evaluating evidence on lead neurotoxcity in children. The extent ofthese problems and ways to control them were expolored in a study of 1291 children from the first class in the schools of Aarhus municipality, Denmark. The lead retention in circumpulpal dentin in shed deciduous teeth was used as an indicator of cumulated lead exposure; it correlated most strongly with traffic density at the residence ofeach family and at the day-care institutions. In a nested case-control group selected on the basis ofdentin lead concentrations, 29 of200 children had encountered obstetrical complications and other medical risks for neurobehavioral dysnction; these children primarily belonged to the low-lead group. As lead-related neurobehaviora effects are nonspecific, inclusion of these children in the data analysis would therefore have distorted the results toward the null hypothesis. Children from the high-lead group who had experienced neonatal jaundice showed impaired performance when compared to other high-lead children; this finding may suggest a synergistic effect. The Bender gestalt test scored by the Gttingen system was the test that was most sensitive to lead exposure. The conclusion that neurobehavioral effects can be caused by the relatively low lead exposures in Denmark may not be surprising, as current exposures to this toxic metal greatly exceed the prepollution levels to which the human body originally adapted.

External costs of atmospheric Pb emissions: valuation of neurotoxic impacts due to inhalation

“…With regard to the IQ loss - Pb blood function, several studies [8,16,18,19,28,29,31] address the topic; most recently Solon [30], with a site study in the Philippines, identifying a relatively high value for the relationship between Pb and IQ (A 3.32 point decline in IQ for each μg/dl increase in Pb blood in children aged 6 months to 3 years). The meta-review of Schwartz [16], however, is widely considered to represent the best global estimate at the present time [1,33].…”

Only one chance: how environmental pollution impairs brain development--and how to protect the brains of the next generation

“…The list is an update of the compilation Grandjean and Professor Philip Landrigan first published in The Lancet in 2006. 1 Moreover, Grandjean has a long association with fluoride research [2][3][4][5][6][7][8][9][10][11][12] including making a keynote presentation at the XIIIth Conference of the International Society for Fluoride Research in New Delhi, India, in 1983. 13 Since 1982, he conducted follow-up studies of the cryolite workers in Copenhagen, Denmark, who were described in a Roholm (1902Roholm ( -1948, whose image appears on the cover of the hard copies of Fluoride.…”