Collecting and Labeling Specimens from People with Possible Exposure to Chemical Agents

Required specimens to collect

Collect the following specimens from each person who may have been exposed, unless otherwise directed.

Whole blood

• Collect blood specimens from adults only unless you receive specific instruction from CDC to collect blood from pediatric patients.
• Collect a minimum of 12 mL of blood.
• Use three 4-mL or larger vacuum–fill only (unopened), non-gel, purple-top (EDTA) tubes; use four tubes if using 3-mL tubes.
• Using indelible ink, mark each purple-top tube of blood in the order collected (e.g., # 1, # 2, # 3, # 4 [if using 3-mL tubes]).
• In addition, collect another specimen using one 3-mL or larger, vacuum-fill only (unopened), non-gel, green- or gray-top tube. Allow the tube to fill to its stated capacity.
• Store samples at 1°C–10°C.

Urine

• Collect at least 40–60 mL from potentially exposed adults and children.
• Use a screw-cap plastic container; do not overfill.
• Freeze specimen as soon as possible (−70 °C or dry ice preferred).
• If other than "clean catch", note method of collection on the specimen cup (e.g., obtained by catheterization).

Blanks

For each lot number of tubes and urine cups used for collection, provide the following to be used as blanks for measuring background contamination:

• Two (2) empty, unopened purple-top tubes.
• Two (2) empty, unopened green- or gray-top tubes.
• Two (2) empty, unopened urine cups.

Labeling specimens

• Label specimens with labels generated by your facility and follow your facility's procedures for proper specimen labeling.
• In addition to unique patient identifiers (e.g., medical records number, specimen identification number) labels should convey the collector's initials, date and time of collection so that law enforcement officials may trace the specimen to the collector should investigations lead to legal action and the collector has to testify that he or she collected the specimen.
• If you use bar-coded labels, place the labels on blood tubes and urine cups so that when these containers are upright, the bar code looks like a ladder.
• Maintain a list of names with corresponding specimen identification numbers at the collection site so that results can be reported to patients. It is recommended that you record additional data for use in the interpretation of results. Additional data may include: time of potential exposure, method of urine collection if other than "clean-catch", indication if sample was collected post-mortem, and antidotes administered prior to sample collection.
• Information provided on labels and lists may prove helpful in correlating the results obtained from CDC's Rapid Toxic Screen and subsequent analysis with the people from whom the specimens were collected.