Mercury concentration in unstimulated whole saliva in high school students in Tehran

Mercury is a natural-occurring metallic substance. There are quantities of mercury found in air, water, soil, and all living matters. It is considered as one of the harmful metals to human being. Study of normal mercury content in human internal organs, blood, urine and saliva can be useful in assessing the level of environmental exposure. Such information may be useful and contributes to medico-legal expert opinions. The present study was conducted to determine the un-stimulated whole saliva mercury content in high school students in Tehran.

This cross sectional study recruited 130 volunteer high school students (65 male, 65 female). They were selected randomly from 5 different geographical sites in Tehran. All examinations conducted in this study were undertaken during the day from 9AM to 12PM, at least 2 hours after last intake of food and drink. By using spilling method, about 5CC of saliva was collected in a specially prepared test tube. Mercury was measured by Cold Vapor Atomic Absorption Spectrometry (CVAAS). SPSS software and Man-Whitney U test were used for data analysis.

The average student age was 16.5 and the average saliva mercury concentration was 0.17 µ g/dl, with 0.20 µ g/dl in males and 0.16 µ g/dl in females. No significant difference was detected between males and females saliva mercury levels.

This study showed that a trace of mercury is detectable in saliva of people who have no amalgam fillings. Such information may be useful for relevant studies conducted in future.