Storage: Toxicological Biological Evidence

(1) Evidence containing toxicological biological material (antemortem or postmortem) shall be stored under conditions that reduce the rate of decomposition and bacterial growth. Ideal conditions for toxicological biological evidence shall be maintained at 0ºC to -30º C (32ºF to -22ºF) (frozen). (2) At no time shall toxicological biological evidence be stored in environments where the potential for large temperature and humidity fluctuations outside of the ideal range exists. Conditions of toxicological biological evidence storage shall include protection from moisture, excessive heat, and protection from sunlight. (4) Tissue samples, liquid urine, or liquid blood shall be stored in impermeable, nonporous, airtight containers such as a metal can or plastic vial and frozen. Glass containers should not be used for long-term storage packaging, as freezing can cause the vial to explode or crack Custodial entities shall avoid employing preservation agents such as formalin or formaldehyde.