To obtain a representative sample of a lot of non-viable cannabis seed, for submission to a laboratory for viability testing
Sampling for viability testing is to be conducted on all lots of non-viable cannabis seed.
A sample is obtained from the seed lot by taking small portions at random from different positions in the lot and combining them. This sample is thoroughly mixed and a smaller sample is drawn for submission to the testing laboratory. The method described here is extracted from the International Rules for Seed Testing (ISTA, 1996).
ISTA, 1996. International Rules for Seed Testing. Seed Science and Technology, Volume 24, Supplement, Rules, 1996.
A small portion taken from one point in the lot. 5.2 Composite sample The combined and mixed primary samples taken from the lot.
The sample submitted to the testing laboratory. The submitted sample may be either a subsample of or the whole composite sample.
Sealed means that the containers in which the seed is held are closed in such a way that they cannot be opened to gain access to the seed and closed again without either destroying the seal or leaving evidence of tampering.
For the purpose of this document, 'seed' refers to the achene of Cannabis sativa L., irrespective of its intended end use, and whether or not it is viable.
A seed testing laboratory that is accredited by the Canadian Food Inspection Agency (CFIA), or a laboratory accredited by the International Seed Testing Association (ISTA) to issue International Seed Lot Certificates.
Stick or sleeve type trier: A hollow brass tube inside a closely fitting outer shell or sleeve which has a solid pointed end. The tube and sleeve have open slots in their walls so that when the tube is turned until the slots in the tube and sleeve are in line, seeds can flow into the cavity of the tube, and when the tube is given a half turn the openings are closed. Exact dimensions are not critical, but for bag sampling a trier 762 mm in length with an outside diameter of approximately 13 mm should be suitable. A bin sampler is of similar construction but much larger, ranging up to 1600 mm in length and 38 mm in diameter.
Nobbe trier for bag sampling: A pointed tube long enough to reach the centre of the bag, with an oval hole near the pointed end. The total length is approximately 500 mm, including a handle of about 100 mm and a point of about 60 mm. An internal diameter of about 10 mm should be sufficient. This trier is not suitable for bin sampling.
Sampling should be carried out by persons trained and experienced in seed sampling. The sampler shall be independent of any commercial interest which might influence the sampling duties being carried out. The national, provincial or state department of agriculture may be able to advise on who can provide this service.
The lot shall not exceed 10,000 kg, subject to a tolerance of 5%. Larger lots shall be subdivided into lots not larger than 10,000 kg, each of which shall be identified by a separate lot designation.
The lot shall be in containers which are self-sealing, sealed (or capable of being sealed) and labelled or marked for identification by a unique lot designation.
At the time of sampling, all containers must be labelled or marked to show a unique lot identification corresponding to the lot identification which will appear on the Certificate of Analysis. The container shall be sealed, or seen to be sealed by the sampler, or be of a self-sealing type. A container shall be regarded as sealed if it is apparently impossible to open without either destroying the seal or leaving evidence of tampering. No sampled lot, or part of a lot, may be left unsealed.
Each stage of sampling the lot shall be performed using appropriate equipment. Such equipment is described in Section 8.
Stick or sleeve type trier: The trier may be used vertically or horizontally. However, when used vertically it must have partitions dividing the instrument into a number of compartments to ensure representative sampling. Using it either vertically or horizontally, the trier in the closed position is inserted diagonally into the bag or container, then opened and turned or agitated to allow it to fill completely. Thereafter it is closed, withdrawn and emptied into a suitable container. If the trier has been inserted through sack walls of coarsely woven jute or similar material, after removal the point of the trier should be run across the hole a couple of times to pull the threads together and close the hole. Holes in paper bags which have been punctured can be closed with an adhesive patch.
Nobbe trier: This trier is not suitable for bin sampling. The trier is inserted gently into the bag, pointing upwards at an angle of about 30° to the horizontal, with the hole facing downwards until it reaches the centre of the bag. The trier is then revolved through 180°, bringing the hole to face upwards, and is withdrawn with decreasing speed so that the quantity of seed obtained from successive locations increases progressively from centre to side of the bag.
Hand sampling: Use of a trier is the preferred method, but if none is available hand sampling may be used. It is difficult by this method to sample deeper than about 400 mm, so it may be necessary for the sampler to request that some bags be fully or partially emptied to facilitate sampling, and then refilled.
For seed lots in bags (or other containers of similar capacity that are uniform in size):
Sample each container and always take at least 5 primary samples.
Sample five containers or at least one in every three containers, whichever is the greater.
Sample 10 containers or at least one in every five containers, whichever is the greater. 401 or more containers: Sample 80 containers or at least one in every seven containers, whichever is the greater.
When sampling seed from any other kind of container or from streams of seed entering containers the following sampling intensity should be used:
|Lot size||Number of primary samples to be taken|
|Up to 500 kg||At least 5|
|501-3,000 kg||One for each 300 kg, but not less than five.|
|3,001-10,000 kg||One for each 500 kg, but not less than 10|
Primary samples of approximately equal size shall be taken from each container sampled, or from each place sampled in the container. The containers shall be selected at random throughout the lot and primary samples drawn from top, middle and bottom of containers, but not necessarily from more than one position in any container. When the seed is in bulk or in large containers, the primary samples shall be drawn from random positions and depths. Seed may be sampled as it enters the containers, provided that the instrument uniformly samples the cross section of the seed stream. It may be operated either under manual or automatic control.
If the primary samples appear uniform they shall be combined to form the composite sample. If they are not uniform, the sampling operation shall be terminated.
The submitted sample shall be obtained by thoroughly mixing the composite sample and drawing off sufficient seed (100g minimum) to submit to the laboratory.
Each submitted sample shall be marked with the same identification mark as the lot. The sample shall be sealed. The sample should ordinarily be packed in bags of jute, other cloth material or paper; they shall not be packed in a moisture proof container. Samples shall be dispatched by the sampler to the seed testing laboratory without delay and shall never be left unattended in the owners's premises or with unauthorized persons. If dispatch of the sample is unavoidably delayed, the sample shall be stored in a cool well-ventilated room in such a way that changes in the quality of the seed are minimized. The testing laboratory must be a recognized laboratory.
Office of Controlled Substances
Document Code : HECS-OCS-005
Revision Number: 002