Dentine lead levels

An analysis of eight cross-sectional and/or prospective studies which reported tooth lead and PbB levels of the same children found considerable consistency among the studies (Rabinowitz 1995). The mean tooth lead levels ranged from under 3 to over 12 pg/g. In a study of 63 subjects, dentin lead was found to be predictive of concentrations of lead in the tibia, patella, and mean bone lead 13 years after tooth lead assessment in half of them (Kim et al. 1996b). The authors estimated that a 10 pg/g increase in dentin lead levels in childhood was predictive of a 1 pg/g increase in tibia lead levels, a 5 pg/g in patella lead levels and a 3 pg/g increase in mean bone lead among the young adults. 

Fergusson DM, Fergusson JE. Horwood LJ, et al. 1988a. A longitudinal study of dentine lead levels, intelligence, school performance and behavior. Part I. Dentine lead levels and exposure to environmental risk factors. J Child Psychol Psychiatry 29 781-792. 

Hansen ON, Trillingsgaard A, Beese I, et al. 1989. A neuropsychological study of children with elevated dentine lead level Assessment of the effect of lead in different socioeconomic groups. Neurotoxicol Teratol 11 205-213. 

Kim R, Hu H, Rotnitzky A, et al. 1996b. Longitudinal relationship between dentin lead levels in childhood and bone lead levels in young adulthood. Arch Environ Health 51(5) 375-382. 

Needleman HL, Gunnoe C, Leviton A, et al. 1979. Deficits in psychologic and classroom performance of children with elevated dentine lead levels. N Engl J Med 300 689-695. 

Needleman HL, Shapiro IM. 1974. Dentine lead levels in asymptomatic Philadelphia school children Subclinical exposure in high and low risk groups. Environ Health Perspect 7 27-31. 

Rabinowitz MB, Leviton A, Bellinger D. 1993. Relationships between serial blood lead levels and exfoliated tooth dentin lead levels models of tooth lead kinetics. Calcif Tissue Int 53(5) 338-41. 

Current opinion comes from the intellectual functioning observed in case reports or large groups of children with varying levels of exposure measured with blood or dentine lead levels. Several reports link mental retardation or autism to higher blood lead levels, but few can determine whether higher lead levels cause the impairment or result from increased pica often observed in mentally impaired children. 

Bellinger D, Needleman HL, Bromfield R, et al A followup study of the academic attainment and classroom behavior of children with elevated dentine lead levels. Biol Trace Elem Res 6 207-223, 1984... 

Hansen ON, Trillingsgaard A, Beese I, et al A neuropsychological study of children with elevated dentine lead level assessment of the effect of lead in different socio-economic groups. Neurotoxicol Teratol 11 205-213, 1989 Haritos NP Chronic lead intoxication a report of 21 treated cases at Children s Hospital. Clinical Proceedings of the Children s Hospital 17 110-115,1961 Harvey PC, Hamlin MW, Kumar R Blood lead, behaviour and intelligence test performance in preschool children. Sci Total Environ 40 45-60, 1984 Hawk BA, Schroeder SR, Robinson G, et al Relation of lead and social factors to IQ of low-SES children a partial replication. American Journal of Mental Deficiency 91 178-183, 1986... 

Fergusson, D.L., Horwood and M. Lynskey. (1997) Early dentine lead levels and educational outcomes at 18 years. J. Child Psychol. Psychiatr. 38 471 78 Finkelstein, Y., M.E. Markowitz and J.F. Rosen. (1998) Low-level lead-induced neurotoxicity in children An update on central nervous system effects. Brain Res. Rev. 27 168-176... 

Needleman, H. L., Gunnoe, C., Leviton, A., Reed, R., Peresie, H., Maher, C. and Barrett, P. (1979). Deficits in psychologic and classroom performance of children with elevated dentine lead levels. N, Engl, J, Med, 300, 689 Neuchay, B. R. and Saunders, J. P. (1978). Inhibitory characteristics of lead chloride in sodium and potassium ATP preparations derived from kidney, brain and heart of several species. Toxicol, Env, Health, 4, 147 Nicander, (2nd Century BC). Theriaca and Alexipharmaca. (Translated into Latin by Euricius Cordus, Frankfurt, 1532). See Major, R. H. (1965)... 

Needleman, H. L., Gunnoe, C., Leviton, A., Reed, R., Peresie, H., Maher, C. and Barrett, P. (1979), Deficits in Psychologic and Classroom Performance of Children with Elevated Dentine Lead Levels, New England J. Med., 300, 689-695. 

Fergusson, D.M., Horwood, L.J., Lynsky, M.T., 1993. Early dentine lead levels and subsequent cognitive and behavioral development. J. Child. Psychol. Psychiatry 34, 215—227. 

Hansen, O.N., Trillingsgaard, A., Beese, I., Lyngbye, T., Grandjean, P., 1989. Neuropsychological profile of children in relation to dentine lead level and socioeconomic group. In Smith, M.A., Grant, L.D., Sors, A.l. (Eds.). Lead Exposure and Child Development An International Assessment. Kluwer Academic, Dordrecht, The Netherlands, pp. 240-250. 

Deficits in psychologic and classroom performance of children with elevated dentine lead levels. 

In some ways, even more important were the results of teachers evaluations, again conducted blind, of 92% of all the children who submitted teeth. Figure 2 illustrates the findings. It can readily be seen that for all the various aspects of classroom functioning there is a tendency for the incidence of dysfunction to increase progressively and in a dose-related manner as the dentine-lead levels increase. For most aspects there is no sign of a threshold of effect, nor even any sign that the differences tend to diminish at lower lead levels. It seems virtually inconceivable that such a consistent pattern of results could... 

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