Use of Unexpired and Expired Blood Alcohol Kits

Potential users of blood alcohol kits have often inquired with NFLS Toxicology Services about the validity of using an expired blood alcohol kit when an unexpired blood alcohol kit is unavailable. This brief outlines the approach recommended by NFLS under such circumstances.

It is highly recommended that Police Agencies maintain a supply of unexpired blood alcohol kits at their location. Use of an unexpired blood alcohol kit will alleviate any legal concerns that may be presented at trial. It will also alleviate any requirement for a forensic toxicologist to attend trial to answer any questions about the reliability of a blood alcohol or blood drug result because of potential issues with the approved container. However, in the unlikely event that a location has not received their order of new and unexpired blood alcohol kits and the only one available is an expired blood alcohol kit, then use of an expired blood alcohol kit is better than using an unspecified blood tube from the hospital. Once the new blood alcohol kits have been received, please dispose of any expired blood alcohol kits to avoid confusion.

If an expired blood alcohol kit is utilized, there is a higher probability that the vacuum in the approved containers has been affected and a full draw of the blood sample to the container's 10 mL capacity cannot be attained. On occasion, it may not be possible to draw a blood sample at all because of the loss of the vacuum. Hence, the recommendation is always use an unexpired blood alcohol kit, if available.

In addition, there may be legal questions relating to the use of an expired approved container, which may require the attendance of a forensic toxicologist to explain. As forensic laboratory capacity continues to be challenged, you may not be able to arrange for a forensic toxicologist to be available to attend at the time and place of the scheduled trial and this may result in dismissal of the case.

From a scientific point of view, use of an expired approved container does not affect the determination of the blood alcohol concentration as the effectiveness of the anti-coagulant and the preservative are maintained.

These chemicals are inorganic salts and do not have expiry dates. NFLS Toxicology Services staff have published a peer reviewed scientific article regarding the validity of blood alcohol results using expired approved containers, and is available here: https://doi.org/10.1080/00085030.2009.10757612

While there is currently no peer-reviewed scientific study examining the effects of expired containers on detection and quantitation of drugs other than alcohol, it is likewise expected that results will not be affected as the effectiveness of the anticoagulant and preservative is still maintained. Nevertheless, these explanations often require the attendance of a qualified forensic toxicologist, and as such, it is recommended to use kits that are within their expiry date, wherever possible.