The Effects of Sulphur Dioxide Upon Established Cell Lines Cultivated in Vitro

Studies have been made on the effects of SO 2 and its salts on strain L, mouse liver, and HeLa cells. Of the cell lines tested, the HeLa cells seemed to be more sensitive to SO 2 and its salts than the cells of mouse origin.Cells cultivated in "biological" medium grow in concentrations of gaseous SO 2 up to 2000 p.p.m., although somewhat inhibited. Cells subjected to a concentration of 500 p.p.m. in this medium are not affected greatly and their growth is comparable to those cells in control cultures.The addition of various salts of SO 2 (Na 2 SO 4 , Na 2 SO 3 , and NaHSO 3 ) in concentrations from 10 to 200 mg% produced responses ranging from complete inhibition of growth (by 200 mg% NaHSO 3 ) to apparent stimulation of growth by some concentrations of Na 2 SO 4 . Toxicity of these salts was in the order of NaHSO 3 > Na 2 SO 3 > Na 2 SO 4 .When cells in vitro are directly exposed to SO 2 in specially designed culture flasks, strain L cells are apparently able to tolerate 5 p.p.m. SO 2 for five 8-hour exposure intervals, provided a "recovery" period follows each exposure.Certain components of serum seem to play a very important role as protective agents in modifying the effect of gaseous SO 2 , possibly by combination.