For the sake of future generations, we need much closer scrutiny of the possible effects of genetically modified foods, writes Dr Elizabeth Cullen
The Irish Doctors' Environmental Association has long-standing concerns in relation to the health impacts of genetically engineered food, and in particular, the decision to grant permission for the planting of genetically engineered potatoes in Ireland. We believe there are good scientific grounds for the opinion that genetic engineering of plants may be both harmful to health and also to our planet.
As background, and simply put, the science of genetics investigates hereditary characteristics. We know that inherited characteristics are passed from generation to generation through genes. Genes are segments of DNA, some of which organise the production of a specific protein. Other genes enable these proteins to interact with one another, and to regulate when, where, by how much and for how long each gene is expressed.
Current genetic engineering technologies do not reflect these interactive processes. Indeed, genetic engineering techniques do not resemble conventional breeding in any way. Instead, the piece of DNA is generally inserted into a virus, which then infects the targeted cell.
This involves the random insertion of selected genes in the absence of the normal regulatory genes. Indeed, it has been argued that gene transfer via current techniques resembles the process of viral infection far more closely than it resembles traditional breeding. There is worldwide concern in relation to the avian flu virus recombining with human influenza virus, but viruses that are used in the genetic engineering process have been found to be able to recombine with natural viruses, and research is ongoing in this area.
A second cause for concern is that the new genes in plants will cause the creation of new proteins, most often alien to the species of the recipient, and in many cases, not normally found in food. These new proteins may, in the worst case, be toxic, allergenic or otherwise detrimental to health. The characteristics of a protein that predispose to it causing an allergy are not always known.
It is difficult to believe there are no peer-reviewed publications of clinical studies on the human health effects of genetically engineered food, despite animal tests giving rise for serious concern. In fact, safety testing of genetically engineered plants is not required if the new plant is deemed to be "substantially equivalent". This term has no scientific meaning; in fact, the very concept itself is profoundly flawed and scientifically unsupportable. It is designed to facilitate rapid commercialisation of genetically engineered crops.
The concept itself does not make sense, for if a genetically engineered plant was the same as its original counterpart, there would be no need to develop it in the first place. The lack of safety testing is disturbing.
US researchers at the National Institute of Health in Bethesda, Maryland, have stated that "there is growing concern among the general public and the scientific community regarding the potential toxicity of genetically engineered organisms". As recently as 2005, researchers at Cornell University expressed concern that little research has been conducted on unintended compositional changes from genetic engineering.
Acknowledging concerns that much of the research into possible adverse health effects from genetically engineered foods had been undertaken by the same companies that promote these products, the state government in Western Australia announced in 2005 that it would fund laboratory testing on rats to determine the safety of genetically modified food crops.
Such research is urgently needed. Results of research to date on animals indicated immune system damage and proliferation of the gastric mucosa in rats fed genetically engineered potatoes, reductions in cellular metabolism and changes in the liver and pancreas in rats fed genetically engineered soya, and lung damage in mice fed genetically engineered peas. Preliminary reports indicate low-birth weight and fatalities in rats fed genetically engineered soya. We note the possibility raised that an outbreak of illness in the Philippines, including respiratory problems and skin reactions, may have been caused by contamination by genetically engineered maize.
The accuracy of testing of existing foodstuffs for the presence of genetically engineered products has also been questioned. It is not possible to determine the extent of uncertainty that a consignment of food or seed is free or not free of genetically engineered products. The justifiable fears generated when StarLink maize intended for animals was found in the human food chain are well documented.
To accurately assess any adverse health impacts in humans, it is necessary to have baseline data collected prior to the introduction of the food under surveillance. We do not have such information in Ireland and health surveillance systems at present in Ireland are not adequate to detect adverse health effects should they arise from this planting.
Foods that contain genetically engineered ingredients need not be labelled if the proportion they contain is less than 1 per cent. However, we know that allergies may be caused by the presence of allergens in much smaller amounts. Have we an increase in allergies to soya products in Ireland? The answer is that we do not know.
We do not deem it acceptable that statutory health agencies, both Irish and internationally, use EU guidelines, which do not reflect current health concerns.
Containment of genetically engineered seed is not possible and seeds will spread by wind, and by people and animals. Children are the most vulnerable as they will have the longest exposure to genetically engineered food.
If this planting is allowed, we will be leaving an irreversible legacy to future generations and we will be guilty of a deliberate betrayal of their interests. The precautionary principle must be invoked in the light of the serious concerns which we have outlined in relation to the impact of genetically engineered food on health. The Irish Doctors' Environmental Association, in the interest of health of present and future generations, requests that a moratorium be declared on the growing and sale of genetically engineered food in Ireland.
When we asked the current EU health commissioner to comment on possible safety aspects of genetically engineered food, he replied that the "EU introduced specific legislation on GMOs to protect its citizens' health and the environment while simultaneously creating a unified market for biotechnology". Genetic engineering has been referred to as "an unholy alliance of bad science and big business". We, and our children, are guinea pigs in a giant global experiment in which nobody is monitoring the results.
• Dr Elizabeth Cullen is a committee member and co-founder of the Irish Doctors' Environmental Association (www.ideaireland.org)