Laser flash photolysis of D 2O 2/RCH 3/N 2 and Cl 2CO/RCH 3/N 2 mixtures (R = CH 3S or H) was coupled with CH 3 detection by time-resolved tunable-diode laser absorption spectroscopy to investigate the importance of CS bond cleavage as an 0 2-independent reaction pathway for the atmospherically interesting reactions of OD radicals and Cl atoms with CH 3SCH 3 at 298 K. Upper limit CH 3 yields derived from the data (95% confidence level) are 0.07 for OD +CH 3SCH 3 and 0.02 for Cl + CH 3SCH 3.