SPINOSAD AQUEOUS SUSPENSION CONCENTRATE
WHO specification 636/SC (February 2007 )
This specification, which is PART ONE of this publication, is based on an evaluation
of data submitted by the manufacturer whose name is listed in the evaluation report (636/2005). It should be applicable to relevant products of this manufacturer, and those of any other formulators who use only TC from the evaluated source. The specification is not an endorsement of those products, nor a guarantee that they comply with the specification. The specification may not be appropriate for the products of other manufacturers who use TC from other sources. The evaluation report (636/2005), as PART TWO, forms an integral part of this publication.
1 Description
The material shall consist of a suspension of fine particles of technical spinosad complying with the requirements of WHO specification 636/TC (February 2007), in an aqueous phase together with suitable formulants. After gentle agitation the material shall be homogeneous (Note 1) and suitable for further dilution in water.
2 Active ingredient
2.1 Identity tests (636/SC/M/2, CIPAC Handbook L, p.121, 2006) The active ingredient shall comply with an identity test and, where the identity remains in doubt, shall comply with at least one additional test. 2.2 Spinosad content (636/SC/M/3, CIPAC Handbook L, p.121, 2006) The spinosad (spinosyn A + spinosyn D) content shall be declared (g/kg or g/l at 20 ± 2oC, Note 2) and, when determined, the average content measured shall not differ from that declared by more than the following
tolerance:
Declared content, g/kg or g/l at 20 ± 2oC Tolerance above 100 up to 250 ± 6% of the declared content above 250 up to 500 ± 5% of the declared content Note: the upper limit is included in each range
3 Physical properties
3.1 pH range (MT 75.3, CIPAC Handbook J, p.131, 2000)
pH range: 6.5 to 8.5.
3.2 Pourability (MT 148.1, CIPAC Handbook J, p.133, 2000)
Maximum "residue": 5%.
3.3 Spontaneity of dispersion (MT 160, CIPAC Handbook F, p.391, 1995) (Note 3)
A minimum of 75% of the spinosad content found under 2.2 shall be in suspension after 5 min in CIPAC Standard Water D at 30 ± 2°C.
3.4 Suspensibility (MT 184, CIPAC Handbook K, p.142, 2003) (Note 3) A minimum of 70% of the spinosad content found under 2.2 shall be in suspension after 30 min in CIPAC Standard Water D at 30 ± 2°C.
3.5 Wet sieve test (MT 185, CIPAC Handbook K, p.148, 2003) (Note 4) Maximum: 0.5% of the formulation shall be retained on a 75 Nm test sieve.
3.6 Persistent foam (MT 47.2, CIPAC Handbook F, p.152, 1995) (Note 5)
Maximum: 20 ml after 1 min.
4 Storage stability
4.1 Stability at 0°C (MT 39.3, CIPAC Handbook J, p.126, 2000)
After storage at 0 ± 2°C for 7 days, the formulation shall continue to comply
with the clauses for:
– suspensibility (3.4);
– wet sieve test (3.5).
4.2 Stability at elevated temperature (MT 46.3, CIPAC Handbook J, p.128,
2000)
After storage at 54 ± 2°C for 14 days, the determined average active
ingredient content must not be lower than 95% relative to the determined
average content found before storage (Note 6) and the formulation shall
continue to comply with the clauses for:
– pH range (3.1),
– pourability (3.2),
– spontaneity of dispersion (3.3),
– suspensibility (3.4),
– wet sieve test (3.5).
Note 1 Before sampling to verify the formulation quality, inspect the commercial container carefully.
On standing, suspension concentrates usually develop a concentration gradient from the top to the bottom of the container. This may even result in the appearance of a clear liquid on the top and/or of sediment on the bottom. Therefore, before sampling, homogenize the formulation according to the instructions given by the manufacturer or, in the absence of such instructions, by gentle shaking of the commercial container (for example by inverting the closed container several times). Large containers must be opened and stirred adequately. After this procedure, the container should not contain a sticky layer of non-dispersed matter at the bottom. A suitable and simple method of checking for a non-dispersed sticky layer "cake" is by probing with a glass rod or similar device adapted to the size and shape of the container. All the physical and chemical tests must be carried out on a laboratory sample taken after the recommended homogenization procedure.
Note 2 Unless homogenization is carried out carefully, it is possible for the sample to become aerated. This can lead to errors in the determination of the mass per millilitre and in calculation of the active ingredient content (in g/l) if methods other than CIPAC MT 3.3 are used. If the buyer requires both g/kg and g/l at 20°C, then in case of dispute the analytical results shall be calculated as g/kg.
Note 3 Chemical assay is the only fully reliable method to measure the mass of active ingredient still in suspension. However, simpler methods such as gravimetric and solvent extraction determination may be used on a routine basis provided that these methods have been
shown to give equal results to those of the chemical assay method. In case of dispute, the chemical method shall be the referee method.
Note 4 This test detects coarse particles (e.g. caused by crystal growth) or agglomerates (crust
formation) or extraneous materials which could cause blockage of spray nozzles or filters in the spray tank.
Note 5 The mass of sample to be used in the test should be specified at the application rate of use recommended by the supplier.
Note 6 Samples of the formulation taken before and after the storage stability
analyzed concurrently after the test in order to reduce the analytical error. test should be
中文
