Objectives: In this study we investigated the cytotoxicity of chloroform on human gingival fibroblasts (HGF) in an established in vitro model.
Methods: HGF cells were isolated and cultured from healthy patients' freshly extracted teeth. The cells were maintained in BioWhittaker UltrCULTURE medium containing 10% fetal bovine serum and antibiotics. The concentrations of chloroform used to treat
HGF were 0 mM(control group), 5 mM, 20 mM and 40 mM, exposed for 30 min or 60 min per day. Cells were stained with crystal violet on day 1, 2 and 4, then dissolved in 10% acetic acid solution and the absorbance was read at 560 nm spectrophotometrically.
Results: On day 1, the bioavailability of HGF treated with 5, 20 and 40 mM for 30 min was 98%, 97% and 86%, respectively; treated for 60 min was 109%, 106% and 97%. On day 2, the bioavailability treated for 30 min was 124%, 91% and 18%; treated for 60 min, 110%, 97% and 18%. On day 4, treated for 30 min were 119%, 19% and 21%; treated for 60 min was 122%, 24% and 13%.
Conclusions: These results suggest that at 5 mM chloroform may enhance some growth of HGF from day1 to day 4. At 20 mM, on day 1 and 2, the bioavailability was not different from the control group, while on day 4 it decreased significantly. At 40 mM, on days 2 and 4, chloroform demonstrated a highly significant toxic effect on HGF.