Cytotoxicity of dental composite components and mercury compounds in pulmonary cells

The cytotoxic potentials of the dental composite components triethyleneglyc oldimethacrylate (TEGDMA) and 2-hydroxy-ethylmethacrylate (HEMA) as well as mercuric chloride (HgCl2) and methyl mercury chloride (MeHgCl) were invest igated. Proliferating A549 and L2 cell monolayers were cultured in the abse nce or presence of composite components or mercurials. Twenty-four hours la ter the tetrazolium salt XTT (sodium 3'- [1-phenyl-aminocarbonyl) -3,4-tetr azolium] bis(4-methoxy-6-nitro)benzenesulphonic acid) was added. Formazan f ormation was quantified using a microtiter plate reader. EC,, values were o btained as half-maximum-effect concentrations from fitted curves. EC50 valu es were in A549 cells (mean values +/- standard deviation; n = 12; mu mol/I ): HEMA 8854 +/- 1882; TEGDMA 1821 +/- 529; HgCl2, 41 +/- 7 and MeHgCl 27 /- 3. EC50 values in L2 cells were: HEMA 191 +/- 28; TEGDMA 112 +/- 16; HgC l2 25 +/- 6 and MeHgCl 8 +/- 6. All tested substances induced a dose-depend ent loss of viability in A549 and L2 cells after 24 h. The EC,, values of b oth mercurials were significantly (p < 0.05) lower compared to the values o f both composite components. TEGDMA was about 5-fold (A549 cells) and about 2-fold (L2 cells) more toxic compared to HEMA. It is to be assumed that th e risk of lung cell damage by dental composite components is even more unli kely. (C) 2001 Elsevier Science Ltd. All rights reserved.