Lead Concentrations of Enamel and Dentine of Deciduous Teeth of Children from Two Finnish Towns

Abstract

The proton-induced x-ray emission method was used to analyze lead concentrations in enamel and dentine of deciduous teeth of 105 6- and 9-yr-old children living in two Finnish towns. Helsinki, the capital city, was assumed to represent high lead exposure and Kuopio, a country town in the middle of Finland, low or moderate lead exposure. In all but two teeth the enamel contained higher lead concentrations than dentine. The individual enamel-dentine lead concentration ratio was not stable but varied greatly. The median dentine lead concentration for 9-yr-old children in Helsinki and Kuopio was 2.0 ppm and 2.9 ppm, respectively, and for 6-yr-old children was 2.5 ppm and 2.7 ppm, respectively. The enamel lead concentrations found in 9-yr-olds in Helsinki and Kuopio were 4.2 and 4.5 ppm, and in 6-yr-olds were 9.1 and 4.4 ppm, respectively. The results reveal low or moderate lead concentrations. Nevertheless, a twofold and statistically significant (P less than .01) increase was found in the enamel of Helsinki children born in 1974 compared with those born in 1971.

Lead content of deciduous molar enamel in Finland, as measured by proton-induced X-ray emission.

“…For instance, permanent tooth enamel in urban samples from the city of Kuopio contained 5.8 ppm, and rural samples 4.9 pprn of lead, when measured with atomic absorption spectrometry (9). With the PIXE technique the lead content of deciduous tooth enamel was 4.5 pprn in Kuopio and 4.2 pprn in Helsinki (7). Even these values are slightly higher than those measured in the present study, but the difference is probably explained by the type of teeth analyzed.…”

“…Other recent studies have also detected relatively low levels of tooth lead in Finland (7,9). For instance, permanent tooth enamel in urban samples from the city of Kuopio contained 5.8 ppm, and rural samples 4.9 pprn of lead, when measured with atomic absorption spectrometry (9).…”

“…Tooth lead content in Finland (7,9), Norway (3,6), and Sweden (13) is lower than in the United States (14, 18). This difference is clearly not a result of methodological factors because the same measuring technique (PIXE) showed (13) that the lead content in permanent tooth enamel was three times higher in samples collected in New York than in samples collected in Stockholm.…”

Concentração de chumbo em dentes de crianças com alterações neurológicas

“…A ______________________________________________________________Introdução 37 concentração deste metal no sangue dura em média 30-40 dias, podendo ocorrer um declínio se o indivíduo não for exposto a novas fontes de contaminação (Altshuller et al, 1962;Attramadal e Jonsen, 1976;Brudevold et al, 1977;Needleman et al, 1979;Haavikko et al, 1984;Rabinowitz, 1990, Ericson, 2001). Isso se deve ao fato do chumbo ser distribuído para os diferentes tecidos do organismo, principalmente os mineralizados, pois o chumbo se comporta de forma muito semelhante ao cálcio (Stewart, 1974).…”

“…Ao longo dos últimos anos, houve um aumento no interesse do acúmulo de metais pesados no corpo humano e em seus efeitos danosos, causados por um crescimento da contaminação ambiental (Haavikko et al,1984). Metais como o zinco e cobre são conhecidos por elementos essenciais, pois participam de funções metabólicas específicas e fazem parte da constituição de várias enzimas; já o chumbo e cádmio são elementos não essenciais e exercem efeitos tóxicos no sistema biológico (Attramadal e Jonsen, 1976).…”