MON810 is a Bt maize event owned by Monsanto that produces a modified form of the Bt toxin Cry1Ab. It was developed by using two transgenic constructs for the Bt toxin, a herbicide tolerance, antibiotic resistance markers and start and stop codons. Using a shot gun method, the DNA sequences were only introduced partially so that MON810 produces only the Bt toxin, while the DNA sequences of the inserts are still not completely identified.
In the last years, a growing number of studies have shown adverse effects of the Bt toxin on non-target organisms, including effects that were only discovered after the the initial cultivation approvals were given. However, research about MON810 is hindered because research and publications about MON810 effects need the approval of Monsanto as the patent holder.
MON810 has been cultivated in the US since 1995. It got cultivation approval in the EU under 90/220 in 1998, but was only introduced to the seed catalogue in 2004. MON810 cultivation is banned in the EU memberstates Austria, Poland, France and Greece. In April 2008 Romania also announced that it would ban its cultivation. In Germany, the sale of MON810 was stopped in 2007 because the authorities did not consider the monitoring plan as sufficient, and even though a new monitoring plan has now be accepted, it has been widely criticized.