Lead content in superficial deciduous enamel from children residing in areas with different
probabilities of lead exposure and the correlation between caries experience and lead
content
Athayde PAA1, Almeida GRC2 *, Gerlach RF2 , Sousa FB1
UFPB
1Depto.
de Morfologia, CCS, Universidade Federal da Paraíba, João Pessoa (PB), Brasil; 2Depto. De Morfologia, Estomatologia Fisiologia, Faculdade de
Odontologia de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto (SP), Brasil.
1 Introduction
a
Calcified tissue harbor lead. However, there are many practical
problems that preclude the use of bone and dentine for wide
screening for lead contamination. Enamel can be easily collected in
mouth by an in vivo biopsy, and shows higher lead concentrations in
teeth from subjects living in polluted environments in comparison to
subjects living in non-polluted ones.
The aim of this study was: to determine lead content in surface
deciduous enamel from children studying in two Kindergartens, one
located in a probably contaminated area (KG1) and another in a
probably non-contaminated area with respect to environmental lead
(KG2), and to test the effect of caries experience on lead content in
surface deciduous enamel.
b
2 Methodology
24 and 22 children form KG1 and KG2, respectively, aged 4-8
yrs old, were undergone to enamel biopsies in upper incisors.
Material from the enamel biopsies was used to measure lead by ICPMS while phosphorus was measured colorimetrically to establish
biopsy depth. Mann Whitney test was used to compare lead content
between the two Kindergartens. Caries experience was determined
using the decayed missing filled per tooth (dmft) index by one
calibrated examiner (Kappa=0.81).
Fig. 1 a, b, c. Enamel biopsy procedure
3 Results
Children from KG1 presented higher mean dmft index compared
to children from KG2 (p<0.01), but no correlation between dmft and
lead content was found (p>0.05). Median lead levels were not
statistically different between KG1 and KG2 considering either all
biopsies depths (KG1=200.5 μg/g; KG2=163.4 μg/g; p=0.88) or only
biopsies deeper than 3.17 µm (KG1=200.83; KG2=130.65; p=0.62).
4 Conclusion
No correlation between dmft and lead content was found and the
main difference between the two KGs was that the one located in a
probably contaminated area presented the higher median lead
content in surface enamel.
5 References
1) ALMEIDA, G. R. C.; SARAIVA, M.C.P.; BARBOSA, F.; KRUG, F.J.;
CURY, J.A.; SOUSA, M.L.R.; BUZALAF, M.A.R.; GERLACH, R.F.
Lead contents in the surface enamel of deciduous teeth sampled in
vivo from children in uncontaminated and in lead-contaminated
areas. Environ. Res., v.104, p.337-345, 2007.
2) ALMEIDA, G.R.C.; GUERRA, C.S.; TANUS-SANTOS, J.E.;
BARBOSA Jr., F.; GERLACH, R.F. A plateau detected in lead
accumulation in subsurface deciduous enamel from individuals
exposed to lead may be useful to identify children and regions
exposed to higher levels of lead. Environ. Res., v.107, p.264-270,
2008.
3) BRUDEVOLD, F.; AASENDEN, R.; SRINIVASIAN, B.N.; BAKHOS,
Y. Lead in enamel and saliva, dental caries and the use of enamel
biopsies for measuring past exposure to lead. J. Dent. Res., v.56,
p.1165-1171, 1977.
4) BRUDEVOLD, F.; REDA, A.; AASENDEN, R.; BAKHOS, Y.
Determination of trace elements in surface enamel of human teeth by
a new biopsy procedure. Arch. Oral Biol., v.20, p.667, 1975.
5) GOMES, V.E.; SOUSA, M.L.R.; BARBOSA, F.; KRUG, F.J.;
SARAIVA, M.C.P.; CURY, J.A.; GERLACH, R.F. In vivo studies on
lead content of deciduous teeth superficial enamel of pre-school
children. Sci. Total Environ., v.320, p.25, 2004.
6) GOMES, V.E.; WADA, R.S.; CURY, J.A.; SOUSA, M.L.R.
Concentração de chumbo, defeitos de esmalte e cárie em dentes
decíduos. Revista de Saúde Pública, São Paulo,v.38, n.5, out. 2004.
Fig. 2. Plot of lead concentration versus biopsy depth
Fig. 3. Plot of dmf-t versus lead concentration
Tab.1. Lead concentration in superficial deciduous enamel (µg/g)
KG1
KG2
Median
200,5
163,4
Min.
64,6
64,19
Max.
689,0
1604,0
Mean
229,0
329,6
p= 0,88
c