Gordon Campbell | Parliament TV | Parliament Today | News Video | Crime | Employers | Housing | Immigration | Legal | Local Govt. | Maori | Welfare | Unions | Youth | Search


Genetically engineered corn - is it safe?

Genetically engineered corn - is it safe?

New studies run over several years each confirmed concerns about the commercialisation of corn genetically engineered with Cry toxins.1,2,3

One study monitored the quantity of Cry toxins in a variety of genetically engineered corn developed by Monsanto (MON 810).1 This corn variety produces an artificial, truncated version of a Cry toxin derived from the bacterium, Bacillus thuringiensis, and was developed to control Lepidopteron insects.

What this study found was that instead of the Cry toxins acting as they would if sprayed on corn plants - releasing a small quantity of the toxin at a single or several occasions - the engineered plant produced the toxin protein during the whole period of its growth. It was also found that the toxin remained biologically active for several years in a dry plant under moderate temperatures. After harvest, the corn stubble was shown to contain a significant quantity of Cry toxin, which could still be detected in plant residues more than a year later. Traces of the toxin were also found in the soil where it could affect essential soil microorganisms.

The researchers looked at doses of Cry-toxins permitted for use in commercial bio-pesticides, including DIPEL. When they compared these with MON 810 Bt-corn, they found that the engineered corn produced 1500-3000 times more Cry1Ab toxin than the dose in a single treatment using DIPEL.

A second study2 analysed the spread of pollen from the MON 810 corn, choosing an area for the trials where no other corn was grown. It established that a conventional variety of corn grown closer than 800 metres was liable to cross-pollination by the MON 810 transgene/s. It also revealed that MON 810 pollen that settled on nearby weeds affected insects, potentially causing species to recede. The researchers established, for example, that the caterpillars of the Peacock and Comma butterflies were extremely sensitive to Cry toxins, and that the dose permitted for use against European corn borer, Ostrinia nubilalis, is 50-times larger than the sensitivity level of these butterflies.

A third study3 revealed that insects have developed resistance against Cry-toxin and that Bt-corn varieties (incorporating a Cry toxin) could have a relatively short 'viability' time. The extrapolation of this is that it will generate a growth in the number of insect populations on which Bacillus thuringiensis products would no longer work. This would pose a severe problem for organic farming, which relies on it almost exclusively.


1. 'Production and decomposition of DK-440 BTY corn,' András Székács, Erik Maloschik, Éva Lauber, László A. Polgár & Béla Darvas, Hungarian Academy of Sciences, Plant Protection Institute, Department of Ecotoxicology and Environmental Analysis, Budapest; Székács, A. et al. (2005) FEBS Journal, 272 Suppl. 1: 508;

Székács, A. et al. (2006) Abs. 52th Hungarian Plant Protection Days,
52: 32;

Granted by Hungarian Ministries of Education (BIO-00042/2000);
Environment & Water (K-36-01-00017/2002, NTE-725/2005).

2. 'Conflicts of DK-440 BTY corn pollen,' Béla Darvas, Éva Lauber &
László A. Polgár Hungarian Academy of Sciences, Plant Protection Institute, Department of Ecotoxicology and Environmental Analysis, Budapest.

Darvas, B. et al. (2004) Növényvédelem, 40: 441-449.

Lauber, É. et al. (2006) Abs. 52th Plant Protection Days, 52: 36;

Bálint, A. (1980) A vetomagtermesztés genetikai alapjai. Mezogazdasági
Kiadó, Budapest. 1-171.

Granted by Hungarian Ministries of Education (BIO-00042/2000);
Environment &
Water (K-36-01-00017/2002, NTE-725/2005).

3. Béla Darvas & Éva Lauber, Hungarian Academy of Sciences, Plant
Protection Institute, Department of Ecotoxicology and Environmental
Analysis, Budapest

Darvas, B. et al. (2005) Abs. 51. Növényvédelmi Tudományos Napok, 51:
9; http://www.omgk.hu/ntn2005.pdf

Darvas, B. et al. (2006) Abs. 52. Növényvédelmi Tudományos Napok, 52:

Granted by Hungarian Ministries of Education (BIO-00042/2000);
Environment & Water (K-36-01-00017/2002, NTE-725/2005).

© Scoop Media

Parliament Headlines | Politics Headlines | Regional Headlines


Minister of Finance: Plan Shows $100 Billion Infrastructure Projects

Finance Minister Bill English has today launched the Government’s Ten Year Capital Intentions Plan (CIP) which shows a pipeline of $100.9 billion worth of infrastructure projects over the next decade. More>>


Werewolf: Safe Landings Gordon Campbell on the safety challenge to the Wellington runway extension.

The safety-related legal challenge revolves around the size of the 90 metre long Runway End Safety Area (RESA) being proposed for the runway extension. More>>


Environment Commissioner: We Need To Work Together On Climate Change And Farming

“The debate around agricultural emissions and the ETS has been polarised for too long,” said the Commissioner. “But the ETS is not the only way forward – there are other things that can be done.” More>>


NZ Super Fund: Seeking To Put A Market Price On Climate Change

Oct. 19 (BusinessDesk) - The New Zealand Superannuation Fund says it will devise a set of rules to assess investment winners and losers under climate change, a strategy that could rule out fossil fuels or producers such as current portfolio member Exxon ... More>>


Rejuvenation: Parata Will Not Contest 2017 Election

Education Minister and National List MP Hekia Parata has today announced that she will not be contesting the next election. She advised the Prime Minister of her decision earlier this year. More>>

Prisons Grow: Government Approves Plans For Increased Prison Capacity

Despite significant progress in reducing crime the number of prisoners has increased faster than projected. This is because the proportion of offenders charged with serious crimes has risen, meaning more people are being remanded in custody and serving more of their sentences in prison. More>>


Gordon Campbell: On Plastic Bag Activism, And Street Harassment

Amusing to see the Act Party experiencing another outbreak of young fogey-ism. What has aroused the ire of Act Leader David Seymour this time is the introduction of a Greens private members bill to the ballot process, calling for a 15 cents levy on plastic bags to reduce pollution. More>>


Unclear Weapons: US Navy Ship Cleared To Visit NZ For Navy's 75th

United States Navy ship, the USS Sampson, has been given clearance to visit New Zealand next month by Prime Minister John Key... “The process for considering the visit by the USS Sampson is the same as that used for all ships attending the International Naval Review." More>>


Get More From Scoop



Search Scoop  
Powered by Vodafone
NZ independent news