Objectives: The aim of the present study was to quantify salivary concentrations of BPA and assess if presence of dental composite fillings is associated with higher BPA levels in saliva.
Methods: The design of the study comprised measurement and comparison of the BPA concentration in saliva from 40 voluntary, healthy participants, between 20-35 years of age. Twenty individuals without any dental composite surfaces (control group) and twenty individuals with six or more dental composite surfaces were recruited from two public dental clinics. Saliva was sampled in polypropylene tubes and stored at -80°C before analysis. Concentration of free and conjugated bisphenol A was determined by liquid chromatography/ mass spectrometry (LC/MS). Values below detection limit of the method (0.1 ng/mL) were set to one half of the detection limit.
Results: Almost all bisphenol A in the saliva samples was free bisphenol A and the concentration was very low. For both groups the median value was below the detection limit. Statistical analysis using Mann-Whitney U-test (one sided; using the Exact Tests Option in IBM-SPSS version 21) indicated that the concentration of free bisphenol A was slightly higher in the exposed group (p=0.044) than in the control group.
Conclusions: This study suggests that presence of dental composites may be associated with slightly higher concentration of free BPA in saliva. However, since the levels of BPA in saliva were very low and the difference between the groups was small, additional studies using sensitive analytical methods are needed before firm conclusions can be drawn.