The following items require special handling as indicated below:
Blood and/or Human Tissue for DNA analysis
All whole blood samples for DNA analysis must be collected by authorized medical personnel and deposited in a vacuum collection tube containing the anticoagulant and preservative Ethylenediamine - tetraacetic Acid (EDTA).
EDTA vials can be recognized by their lavender-colored rubber stoppers and are available at the Coroner's Office and all hospitals. The vial should be completely filled with blood and shaken thoroughly to mix the preservative with the blood. The investigator should observe the drawing of blood to maintain the chain of custody.
Whole blood and human tissue samples collected for DNA reference purposes shall be submitted to Scientific Services Bureau (SSB), Hertzberg-Davis Forensic Science Center, at the earliest opportunity. If the submission must occur after business hours, the submitter should contact a Biology Section supervisor for proper handling and subsequent storage procedures. After hours, a biology supervisor may be contacted through the SSB dispatch desk (213-989-2163 or 800-974-4LAB) at Scientific Services Bureau, Beverly facility. If it is necessary to delay the delivery of the blood sample to the laboratory for more than 24 hours, the sample should be refrigerated BUT NOT FROZEN.
Blood for Toxicology (Drugs or Alcohol) analysis
All whole blood samples for toxicology (drugs or alcohol) analysis must be collected by authorized medical personnel and deposited in a vacuum collection tube containing potassium oxalate (an anticoagulant) and sodium fluoride (a preservative).
These vials can be recognized by their grey-colored rubber stoppers and are available at all hospitals or in the Department-provided blood collection kits. The vial should be completely filled with blood and shaken thoroughly to mix the preservative with the blood. The investigator should observe the drawing of blood to maintain the chain of custody.
Whole blood samples collected for toxicology (drugs or alcohol) purposes can be submitted to Scientific Services Bureau (SSB) through SSB Evidence Couriers or over the counter at the Century, Lancaster, and West Covina regional laboratories, or at the Downey or Hertzberg-Davis Forensic Science Center facilities. The Toxicology or Blood Alcohol section supervisor can be reached at the Downey Facility (562-940-0248). These blood samples do not need to be refrigerated; they should NOT BE FROZEN.
Explosives
Explosives, other than fixed ammunition, are not to be stored at a station/unit except in an emergency and with the approval of the Arson/Explosives Detail. Procedures for handling and storing of explosives are detailed in the Emergency and Disaster chapter.
Footprints - Tire Tracks - Tool Marks
Footprints, tire tracks, tool marks, or other items of potential impression evidence that are observed on surfaces which cannot be readily collected shall be preserved by covering them in a manner which will not disturb them pending arrival of Scientific Services Bureau staff.
Gunpowder /Gunshot Residue Patterns
Clothing containing gunpowder or gunshot residue patterns should be neatly folded and protected from excessive friction on the patterned area. If wet with blood or water, the clothing must be air dried prior to folding and packaging.
In order for the distance from which the firearm was fired to be determined from the clothing, the firearm and ammunition used must be submitted to Scientific Services Bureau.
Narcotics
All narcotics, with the exception of suspected plant materials, shall be packaged in transparent evidence bags. This packaging takes the place of the pre-printed manila envelopes previously used. Plant materials shall be packaged in manila envelopes or paper bags.
Scientific Services Bureau may repackage narcotics seized in bindles, envelopes, pouches, boxes, etc., so that the analyzed narcotics with the original packaging material and the unexamined narcotics in the original packaging material can be viewed without re-opening the transparent narcotic evidence bag.
Nitrous Oxide (N2O) Tanks
Nitrous oxide is commonly found in compressed gas tanks, and the collection and handling of compressed gas tanks presents the potential for significant safety issues. Although not a flammable gas, nitrous oxide is a compressed gas and may present a safety hazard if it is improperly stored. Compressed gas tanks shall be initially inspected for damage prior to transport to Scientific Services Bureau (SSB) for sampling. If the tank appears to be unaltered, visually inspect the valve areas for damage and/or corrosion. If the tank appears altered in any way or appears unsafe, contact either the fire department or Arson/Explosives Detail.
Scientific Services Bureau, Controlled Substances (Narcotics) supervisors shall be contacted before tanks are submitted to the laboratory.
Removable Articles
Articles of evidence which can be removed from the scene shall be handled with utmost caution to prevent any damage, alteration, or contamination.
Sexual Assault Cases
The clothing of the victim and the suspect should be dried and packaged separately. Clothing may have particles of debris from the scene; therefore, it is imperative that neither the victim nor the suspect be allowed to return to the scene of the crime wearing the same clothing.
Clothing may be extremely valuable as evidence. With the victim's consent and when a change of clothing is available, the victim’s clothing should be collected, air dried (if wet), and placed in paper bags. Each piece of clothing should be packaged separately. The hospital should attempt to arrange for clothing for the victim.
Sexual assault evidence shall be collected by an expert during the medical examination of sexual assault victims, utilizing the sexual assault evidence collection kits provided by Scientific Services Bureau.
A specialized evidence collection package to be used in sexual assault cases has been provided to stations, units and hospitals. It contains the necessary specimen swabs and slides, bags for clothing, and other items to facilitate collection of physical evidence.
Wet or Damp Items
Wet or damp items such as those to be examined for blood, seminal fluid, DNA (e.g., wet buccal swabs), handwriting, or latent fingerprints must be allowed to air dry thoroughly prior to packaging for transfer to Scientific Services Bureau. Alternatively, upon approval from laboratory staff, wet or damp items may be hand carried directly to either the Beverly or Hertzberg-Davis Forensic Science Center Crime Laboratory facilities to be dried in the laboratory’s drying cabinets.