Migration test methods

The electrochemical migration test requires that any degradation in insulation resistance value be less than a decade. The Telcordia Electrochemical Migration test method has also become an IPC test method (TM 2.6.14.1). Table 1 compares the variation in SIR and electrochemical migration test conditions for telecommunications test versus the non-telecommunication applications. 

A migration test was developed to simulate human exposure patterns. 5 g of rubber material was cut into 1-2 mm stripes and then immersed in 20 ml of standard test solution of artificial saliva (4.2 g NaHC03, 0.2 g K2CO3, 0.5 g NaCl, 0.03 g NaNO, ad 1000 ml with aqua dest.j. After 24 h incubation at 40 C volatile nitrosamines were determined in an aliquot and determined after destination with a standard technique (GC-TEA-method). 

Applications Radiotracer measurements, which combine high sensitivity and specificity with poor spatial resolution, have been used for migration testing. For example, studies have been made on HDPE, PP and HIPS to determine effects of manufacturing conditions on migration of AOs from plastic products into a test fat [443]. Labelled antioxidant was determined radio-analytically after 10 days at 40 °C. Acosta and Sas-tre [444] have used radioactive tracer methods for the determination of styrene ethyl acrylate in a styrene ethyl acrylate copolymer. 

Guide to test methods for the specific migration of substances from plastics... 

Europe s controversy over soft PVC toys looks set to continue after EU health experts rejected the best available method for assessing the dangers to children. The so-called Dutch migration test was designed to mimic the way phthalate softeners leak out of PVC when it is sucked or chewed. Manufacturers had hoped the EU s Scientific Committee for Toxicity, Ecotoxicity and the Environment would accept the method as a standard test for phthalate migration, allowing it to be used across the EU, but the committee ruled that the Dutch test was unreliable. It also rejected a similar test developed in the UK, and issued a list of changes that would have to be made before either... 

The European Commission has mandated the European Committee for Standardization to establish a validated method of analysis for the determination of OMLs and SMLs. If a product complies with the compositional requirements of the directives, i.e., it is produced from authorized monomers and additives, then it may be tested for any desired application. If it meets the migration requirements, it is acceptable for use in cases covered by that test method. Typical food simulants used in the tests are hot water, acetic acid, ethyl alcohol and olive oil. The choice of an appropriate simulant depends on the type of food expected to come into contact with the packaging. 

The gravimetric determination of the residue from overall migration tests or extraction tests is at the milligram scale. As mentioned above, the EU limit for overall migration is 60 mg/kg. With some caveats, measuring at these levels is relatively simple in even the most basic laboratory and official methods are well described. 

During method development and validation, a number of practical difficulties may occur and need control. An already well-known major phenomenon which can cause problems to the analyst is for instance insufficient or even zero recovery of analytes from the migration test solution. Possible reasons for that may be ... 

An important conclusion from these findings was that even though this analytical method works in principle with olive oil as a food simulant, the migration test using olive oil or another fat simulant can provide false-negative results. Therefore, the method should only be applied in the case of short exposure periods with olive oil. If the method is carried out with olive oil, a recovery check with spiked olive oil applying the same time/temperature migration test conditions is necessary. In the case that such a recovery check indicates loss" of HMDA and/or EDA, then alternatively 95 % ethanol or iso-octane should be used as substitute fatty food simulants. 

Tice P, 1997, European Committee for standardization (CEN) - Progress with standard test methods. In R. Ashby, I. Cooper, S. Harvey and P. Tice Food Packaging Migration and Legislation. Pira International, Leatherhead 1997 (Appendix to Chapter 2, p 37). 

Figge, K. 1980, Migration of Components from Plastics-Packaging Materials Into Packed Goods - Test methods and Diffusion Models. Progress Polymer Science, 6, 187-252. 

Figge, K., 1980, Migration of components from plastics-packaging materials into packed goods - test methods and diffusion models. Prog. Polym. Sci., 6,187-252. 

This article briefly describes new Dutch and UK test methods for measuring the migration of phthalate plasticisers in PVC toys. Companies Hasbro and Mattel have already adopted these methods. The Toy Industries of Europe organisation hopes that the new test methods will eventually lead to a common method within the EU to ensure the safety of toys and child care items to reassure consumers, and hopes that their use will spread to other member states. 

Debeaufort, F., Quezada-Gallo, J.A., and Voilley, A. (2000). Edible barriers A solution to control water migration in foods. In Food Packaging Testing Methods and Applications. American Chemical Society, Washington, DC, pp. 9-16. 

Materials and articles in contact with foodsmffs - Plastics - Part 1 Guide to the selection of conditions and test methods for overall migration... 

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