1. Sulfur 35

2. S35-2 Characteristics Radioactive half-life: 87.4 days Decay mechanism: Beta emission Energy:Emax = 167 keV Eavg = 49 keV Contamination monitoring: Thin window Geiger- Mueller detector, liquid scintillation counter for wipe surveys Dosimetry: Urinalysis

3. S35-3 Decay Table Days0123456 7 1000992984976969961954 14 946939931924916909902 21 895888881874867860863 28 847840833827820814807 35 801795788782776770764 42 717711705700694689683 49 678373667662657652646 56 941636631626621616612

4. S35-4 Volatility Radiolysis of S-35 labelled amino acids may lead to the release of S-35 labelled volatile impurities. Delivery vials should therefore be opened in a fume hood

5. S35-5 Stabilizers The addition of stabilizers (buffers) will reduce, but not eliminate, the evolution of S-35 volatiles from tissue culture media. Incubators should be checked for contamination after using S-35 methionine or other volatile compounds.

6. S35-6 Differentiation Difficulty S-35 may be difficult to distinguish from C-14. If both nuclides are being used in the same laboratory, establish controls to ensure they are kept separate. If "unknown" contamination is found, treat it as C-14.