Risk assessment and risk management of specific receiving environments

As Dr. Amanda Gálvez Mariscal briefly mentioned in her introduction, water also needs to be considered.

Even though LM plants are grown on land, surface waters can play a role either as a transport medium or as a medium where parts of the plant degraded and persist in a different way then on land, and where transgenic products get in contact with different organisms then on land.

Tree branches regularly get swept along by streams and get deposited along the banks where – depending on species - they can set root again.

In addition some plants rely on surface water or the sea to transport their seeds (hydrochy, drift seeds). Especially Mucuna and Dioclea species rely on rivers to disperse their seeds towards oceans and distant beaches.

Even in agricultural landscapes plant material gets deposited in surface waters (Rosi-Marshall et al. 2008). For plants producing transgenic proteins, this results possibly in a different rate of degradation and persistence in water or the aerobic and anaerobic areas of the sediment, as well as exposure of different organisms to the transgenic protein (Douville et al. 2008).

Douville et al. not only found Bt toxins from transgenic crop plants in surface water and sediment, but also observed an accumulation of transgenic Cry proteins in mussels.

First studies with the effects of Cry toxins on caddis flies (Rosi-Marshall et al. 2007) and Daphnia show that adverse effects can occur in water organisms.

Surface waters therefore need to be taken into account as a specific receiving environment.


Bøhn T, Primicerio R, Hessen DO & Traavik T (2008): Reduced Fitness of Daphnia magna Fed a Bt-Transgenic Maize Variety. Archives of Environmental Contamination and Toxicology, DOI 10.1007/s00244-008-9150-5.
Douville M., Gagné F., Andre C. & Blaise C. (2008): Occurrence of the transgenic corn cry1Ab gene in freshwater mussels (Elliptio complanata). Ecotoxicology and Environmental Safety: doi:10.1016/j.ecoenv.2008.02.006.
Rosi-Marshall et al. (2007): Toxins in transgenic crop byproducts may affect headwater stream ecosystems. PNAS 104(41): 16204-16208.