In 2009, the CORESTA Smokeless Tobacco Sub-Group (now called Tobacco and Tobacco Products Analytes Sub-Group) coordinated the manufacture of a series of smokeless tobacco reference products for use in scientific studies. The reference products are referred to as CORESTA Reference Products or CRPs. The 2009 CRPs include the following:
- CRP1 - Swedish style snus pouch
- CRP2 - American-style loose moist snuff
- CRP3 - American-style loose dry snuff powder
- CRP4 - American-style loose-leaf chewing tobacco
Due to high demand for the 2009 CRPs the Sub-Group coordinated the manufacture of a second batch CRPs in 2016. The 2016 CRPs were produced in the same style as the 2009 CRPs except the loose-leaf chewing tobacco was produced in a chopped format. The 2016 CRPs include the following:
- CRP1.1 - Swedish style snus pouch
- CRP2.1 - American-style loose moist snuff
- CRP3.1 - American-style loose dry snuff powder
- CRP4.1 - American-style chopped loose-leaf chewing tobacco
North Carolina State University Tobacco Analytical Services Laboratory (TASL) (https://strp.wordpress.ncsu.edu) serves as the central repository for the 2009 and 2016 CRPs where the reference products are stored at -20 °C. The 2009 CRPs have been shown to be stable through 2015 when stored at these conditions. Investigators should be aware that depending upon how these products are transported and stored, moisture content and chemical constituents may change over time.
Basic information on these products is available by clicking on the relevant CRP products link (in blue in the list above). The CORESTA Tobacco and Tobacco Products Analytes (formerly Smokeless Tobacco) Sub-Group routinely conducts collaborative studies, including stability studies, with the CRPs. Study reports and analytical methods for the analysis of smokeless tobacco products can be found on this website on the Tobacco and Tobacco Products Analytes Sub-Group webpage or by searching the Documents section.
Sample Storage, Handling, and Analysis
Upon receipt, investigators should immediately place the sealed CRPs at approximately -20 °C until analyses can be performed. The CRPs may be refrigerated for short term storage of approximately 1 week or less.
Prior to analysis, the CRPs should be removed from -20 °C and placed in a refrigerator for a minimum of 24 hours. This will allow water to become thoroughly re-equilibrated throughout the CRPs. After removal from the refrigerator, the CRPs should be allowed to equilibrate to ambient conditions before opening. After opening, the samples can be placed in a sealed container for short term storage in the refrigerator. Individual researches must determine the stability of the reference products after removal from -20 °C. Stability will be dependent upon the analyses that will be conducted.
The CORESTA Tobacco and Tobacco Products Analytes Sub-Group recommends the following procedure for subsequent handling of the CORESTA Reference Products (CRPs):
- Snus pouches (CRP1 & CRP1.1) should be cut into two halves and the tobacco and pouch material be added directly to the extraction vessel for chemical analyses. Unit pouches should be analysed to mitigate the difficulty in preparing a homogenous tobacco and pouch mixture.
- Moist Snuff reference products (CRP2 & CRP2.1) and Dry Snuff reference products (CRP3 & CRP3.1) do not require sample grinding prior to analysis.
- The 2009 CRP4 is typical of a loose leaf chewing tobacco consisting of large pieces of the tobacco blend components. Reproducible analysis of this product requires grinding an entire pouch to ensure within-pouch sample homogeneity. It is recommended that CRP4 be frozen in liquid nitrogen before being ground in a standard laboratory mill. Cryogrinding will ensure the sample does not degrade due to the generation of heat during the grinding process. The 2016 CRP4.1 was produced with the product characteristics of a loose leaf chewing tobacco; however, it was produced in a chopped format. For this reason, CRP4.1 does not require grinding prior to analysis. This product is similar in appearance to moist snuff.