Adventitious Presence

Adventitious Presence

Thresholds, Coexistence and ‘Zero Tolerance’

“Zero tolerance” – claim and reality

Many debates on GMOs focus on whether or not biotech and non-biotech farming models can be run in parallel, can “co-exist” next to each other, and what measures may be needed to assure such co-existence.

As farming (and this is similarly true for plant breeding and seed production) takes place in the open environment, it has always been acknowledged that a certain level of ‘impurities’ of different produce needs to be accepted. This is true for example for the level of soil or other matter that may be picked up during harvest or transport and that may still be present even after several stages of cleaning. Or the number of other species present in a batch of a specific crop, e.g. of barley kernels in a wheat batch or vice versa. Depending on the biology of the crops and taking into account practical, economic and environmental or industrial considerations, these ‘tolerance levels’ vary.

For GM crops and specifically for GM seed, however, the EU claims to apply a ‘zero tolerance policy’, suggesting that European products (or products imported into the EU) may not contain any traces of a GM product not yet specifically authorized for the EU. With Europe chronically lagging behind in its GM authorisation process in comparison to the main producing and exporting countries and in view of its dependency on commodity imports, this claim, however, is just another myth rather than a reality.

The EU and the presence of GMOs in seed

This becomes specifically evident in the discussion of possible tolerance levels (or “thresholds”) for the presence of GMOs in non-GM, conventional seed.

Like commodity crop production, breeding and seed production are carried out in the open environment. With more and more GM crop production worldwide - and constantly increasing GM seed production for these increasing acreages - a complete segregation of the GM and non-GM production lines becomes not only economically unsustainable but also practically impossible.

Consequently, breeders and seed producing farmers asked the European Commission already in the years 1999/2000 to establish some tolerance levels (or “thresholds”). Today, a good 15 years later, the seed sector is still waiting…

See also

Documents & Publications