Indicator biotechnology

Presence of genetically modified rapeseed in the environment

Due to a moratorium, Switzerland has banned the release of genetically modified organisms (GMOs) into the environment for other than scientific purposes. However, some agricultural exporting countries such as the U.S. and Canada are now cultivating them on a large scale. As a result, genetically modified plants can end up contaminating goods that are imported into Switzerland and eventually enter the environment. This risk must be curbed as much as possible to prevent the contamination of conventional agricultural crops and any damage to biodiversity.

Assessment of the state
impossible to evaluate impossible to evaluate
Assessment of the trend
impossible to evaluate impossible to evaluate
Legend for 2014: 0 of all 620 sampled plants were GM-positive.

Data for the graph: Excel
Source: FOEN
Legend for 2014 : At 57 hotspots, 38 of a total of 3,042 sampled plants were GM-positive.

Data for the graph: Excel
Source: FOEN

Environmental monitoring results show that the percentage of plants that test positively is low (less than 2% on average), although the possibility that genetically modified rapeseed plants could accidentally end up in the environment cannot be entirely ruled out. The high value for 2017 (cf. graph "Hotspots") can be explained by the fact that several samples were collected during that year from an unknown site at which geneticallly modified rapeseed is frequently found. One major reason for the presence of genetically modified organisms in the environment is that contaminated agricultural products are imported from countries where genetically modified plants are grown. Consequently, the presence of genetically modified plants in Switzerland cannot be prevented entirely. Hence, the cantons continuously apply control measures against genetically modified plants wherever positive test results are found and, in doing so, continue to ensure that no new and lasting populations of plants can be created by genetically modified seeds present in the soil.

The current results show that the developed methods provide reliable figures on the presence of genetically modified rapeseed in the environment and form a solid basis for analysing longer-term developments.

The state of this indicator is not assessed. The data primarily depend on external factors such as the volume of GMO-contaminated products imported into Switzerland.


To ensure early recognition of any damages caused by the presence of GMOs in the environment, the FOEN developed an annual monitoring system for genetically modified rapeseed along the interoperable SBB railway network (1,340 km). For this purpose, 30 randomly selected 1-km-long sections of railway across Switzerland are surveyed for the presence of GM rapeseed. Hot spots, which are sites where GM rapeseed is much likelier to be found (i.e. places where goods are handled, such as warehouses and rail freight stations or transport hubs and access routes for food and feed companies), are also surveyed for the presence of GM rapeseed.

The Cantonal Laboratory of Basel-Stadt (KLBS), various authorised agents and cantonal authorities take samples following the concept developed by the FOEN. The samples are analysed in the reference laboratory (Cantonal Laboratory of Basel-Stadt, KLBS) for the presence of genetic modifications (e.g. resistance to herbicides or antibiotics) using real-time PCR.

Last updated on: 04.07.2019

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