Mexico city has a very high pollution index. Based on the view 'that s
alivary monitoring can be extended to environmental pollutants', we pe
rformed this study in order to determine not only the concentrations o
f lead and cadmium in human saliva, but also to establish their possib
le association with some socio-demographic factors. One hundred dental
students from the National Autonomous University of Mexico living in
Mexico city participated in the study. Stimulated human whole saliva s
amples were analyzed by atomic absorption spectroscopy. The results sh
ow that Pb ((x) over bar=3.10 mu g/dl(-1); maximum (x) over bar=16.8 m
u g/dl(-1) and minimum, (x) over bar=0.04 mu g/dl(-1)) and Cd ((x) ove
r bar=0.25 mu g/dl(-1); maximum (x) over bar=2.04 mu g/dl(-1) and mini
mum (x) over bar=0.004 mu g/dl(-1)) concentrations were higher than th
ose reported elsewhere, and that there was no association between seve
ral variables studied (age, gender, geographic area and consumption of
canned food) and salivary Pb. However, an inverse association was fou
nd between Cd and age (chi(2)=5.9012; P less than or equal to 10.05; g
amma=-0.5224, P less than or equal to 0.05). From this study it can be
concluded that saliva has potential as a technique for monitoring amb
ient pollutants recent exposure, since circulating levels of certain p
olluting chemicals can be transported into salivary glands and secreti
ons. (C) 1997 Elsevier Science Ireland Ltd.