Bt in the water

April 2011

Aquatic wildlife

In 2007, a US study looked at the potential for Bt corn by-products to poison waterways.

It found that GM plant detritus and pollen make their way into streams. Once there, they can be sequestered, consumed or carried considerable distances.

Insect life in the streams which consumed such GM plant debris had reduced growth and increased mortality. Other animals which feed on algae contaminated with Bt pollen were also noted to be at risk.

Sources:

• Adapted from 'Bt is a TOXIN' which first appeared on GM-free Scotland in September 2008
• E. J. Rosi-Marshall et al., Toxins in transgenic crop byproducts may affect headwater stream ecosystems, http://www.pnas.org//, received for review 5.03.07

Farmed fish

It's well-known that a large proportion of non-organic dairy, meat, eggs and poultry in the EU comes from animals raised on GM feed. Green groups have been campaigning long and hard to get this hidden source of GM out of our food-chain.

Less well-known is that fish reared in fish farms, are likely to have been fed GM soya and maize.

Studies have revealed that Atlantic salmon fed on a diet of Bt maize, MON810, have increased levels of stress-marker proteins and have altered proportions of white blood cell types indicative of an immune system reaction.

Like all intensively farmed animals, fish can often only be kept free from disease by treatment with chemicals, and are slaughtered long before they get old. Chronic health problems will not, therefore, be obvious in them.

Eating the flesh of stressed or unhealthy animals is not a healthy option.

Sources

• Adapted from 'FISH TOO' which first appeared on GM-free Scotland in December 2008
• Sagstad, et al., Evaluation of stress- and immune-response biomarkers in Atlantic salmon, Salmo salar L., fed different levels of genetically modified maize Bt maize, compared with its near-isogenic parental line and a commercial suprex maize, Bull Acad Natl Med., April-May 2007