Cytotoxicity of dental composite components and mercury compounds in lung cells.
OBJECTIVE
The effect of dental composite components triethyleneglycoldimethacrylate (TEGDMA) and hydroxyethylmethacrylate (HEMA), as well as mercuric chloride (HgCl2) and methylmercury chloride (MeHgCl) was investigated on the release of lactatedehydrogenase (LDH) from alveolar epithelial lung cell lines in vitro.


METHODS
The confluent cell layers from the A549 (human, malignant) and the L2 cells (rat) were incubated with various concentrations of HEMA, TEGDMA, MeHgCl and HgCl2 at 37 degrees C in 2% (v/v) CO2 atmosphere for 8h. In further experiments the L2 cells were incubated with the same compounds for 6-48 h. LDH release was measured and the values were expressed as percentage of the LDH content. The values were plotted on a concentration log-scale and the substance concentration at the maximum slope was assessed as effective concentration (EC50).


RESULTS
A significant (p<0.05) increase in the LDH release was found in the L2 cells after 8-h incubation with HEMA (4 mmol/l), TEGDMA (2 mmol/l), MeHgCl (0.01 mmol/l) and HgCl2 (0.015 mmol/l), and in A549 cells with HEMA (14 mmol/l), TEGDMA (15 mmol/l), MeHgCl (0.15 mmol/l) and HgCl2 (0.05 mmol/l), compared to controls. The EC50 values from compounds in the L2 cells are shown in the following table (mean; sem in parentheses; n=3-6; #n=1): [see text].


CONCLUSIONS
The toxic effect of HgCl2 and MeHgCl from the L2 cells was about 100-700-fold higher than of the dental composite components. A significant (p<0.05) time dependent increase of toxicity was observed with TEGDMA, HEMA and MeHgCl.
Reichl
F X
FX
Walther-Straub-Institute of Pharmacology and Toxicology, Ludwig-Maximilians-University of Munich, Nussbaumstr. 26, 80336, Munich, Germany. f.x.reichl@lrz.uni-muenchen.de
Walther
U I
UI
Durner
J
J
Kehe
K
K
Hickel
R
R
Kunzelmann
K H
KH
Spahl
W
W
Hume
W R
WR
Benschop
H
H
Forth
W
W
D000818:Animals; D000891:Anti-Infective Agents, Local / Q000633:toxicity; D001672:Biocompatible Materials / Q000633:toxicity*; D002460:Cell Line; D003188:Composite Resins / Q000633:toxicity*; D003764:Dental Materials / Q000633:toxicity*; D004847:Epithelial Cells / Q000187:drug effects; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000187:drug effects; D016014:Linear Models; D008168:Lung / Q000166:cytology / Q000187:drug effects*; D008175:Lung Neoplasms / Q000473:pathology; D008627:Mercuric Chloride / Q000633:toxicity; D017669:Mercury Compounds / Q000633:toxicity*; D008689:Methacrylates / Q000633:toxicity; D008767:Methylmercury Compounds / Q000633:toxicity; D011092:Polyethylene Glycols / Q000633:toxicity; D011109:Polymethacrylic Acids / Q000633:toxicity; D011650:Pulmonary Alveoli / Q000166:cytology / Q000187:drug effects; D051381:Rats; D013223:Statistics as Topic; D013696:Temperature; D013997:Time Factors; D014407:Tumor Cells, Cultured
D000891:Anti-Infective Agents, Local; D001672:Biocompatible Materials; D003188:Composite Resins; D003764:Dental Materials; D017669:Mercury Compounds; D008689:Methacrylates; D008767:Methylmercury Compounds; D011109:Polymethacrylic Acids; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; D008627:Mercuric Chloride; C005044:hydroxyethyl methacrylate; D007770:L-Lactate Dehydrogenase; C004925:methylmercuric chloride