The more testing is done, the more contamination is found

Genewatch and Greenpeace have, for about 10 years, run a GM Contamination Register (www.contaminationregister.org). They have now analysed the cases on the Register and a resulting paper has been published in an open access journal.

The GM Contamination Register database contains cases dating back to 1997 (the start of GM crops). It records nearly 400 cases (to the end of 2013). The authors analysed the cases by crop and by country. Finally, they focused on cases of contamination arising from unauthorised GM crops (i.e. those without any authorization for commercial growing anywhere in the world).

The paper makes a useful reference for these GM contamination cases. The main points are:

1) GM contamination happens.
2) GM contamination from field trials/illegal plantings happens – there are 9 cases of GM contamination of unauthorized (non-commercialised) GM crops that haven’t undergone any environmental or food safety analysis.
3) GM rice tops the league table of contamination cases by crop, accounting for about a third of cases. This is despite the fact that there is no GM rice grown anywhere in the world. The authors suggest this figure might be related to the routine testing of imports of GM rice at national borders.
4) Once GM contamination has happened, it can be difficult to contain it, e.g. GM papaya, GM Chinese rice (but US LL rice appears to have stopped – for now at least).
5) From these data, it’s not clear what the main factors affecting contamination rates are. It’s not only the GM contamination itself (cross-pollination, mix-ups etc.) that contributes to the number of cases, but also the the testing regime (both routine and targeted). The highest rates of contamination are in imported foodstuffs to Germany but this is probably because they do a lot of testing. All EU countries have high rates because they report their findings of the RASFF database. The data for contamination exists – but not the factors to analyse what influences contamination.
6) Finally, for most (perhaps all) experimental GMOs there is no protocol for testing available, making detection of any GM contamination difficult, if not impossible.

Reference for the paper:
Price B, Cotter J (2014). The GM Contamination Register: a review of recorded contamination incidents associated with genetically modified organisms (GMOs), 1997–2013. International Journal of Food Contamination 2014, 1:5. http://link.springer.com/article/10.1186/s40550-014-0005-8