Seed contamination

Since the advent of genetic engineering in the 1970s, concerns have been raised about the dangers of the technology. Laws, regulations, and treaties were created in the years following to contain genetically modified organisms and prevent their escape. Nevertheless, there are several examples of failure to keep GM crops separate from conventional ones. Since the advent of genetic engineering in the 1970s, concerns have been raised about the dangers of the technology. Laws, regulations, and treaties were created in the years following to contain genetically modified organisms and prevent their escape. Nevertheless, there are several examples of failure to keep GM crops separate from conventional ones. In the context of agriculture and food and feed production, co-existence means using cropping systems with and without genetically modified crops in parallel. In some countries, such as the United States, co-existence is not governed by any single law but instead is managed by regulatory agencies and tort law. In other regions, such as Europe, regulations require that the separation and the identity of the respective food and feed products must be maintained at all stages of the production process. Many consumers are critical of genetically modified plants and their products, while, conversely, most experts in charge of GMO approvals do not perceive concrete threats to health or the environment. The compromise chosen by some countries - notably the European Union - has been to implement regulations specifically governing co-existence and traceability. Traceability has become commonplace in the food and feed supply chains of most countries in the world, but the traceability of GMOs is made more challenging by the addition of very strict legal thresholds for unwanted mixing. Within the European Union, since 2001, conventional and organic food and feedstuffs can contain up to 0.9% of authorised GM material without being labelled GM (any trace of non-authorised GM products and would cause shipments to be rejected.). In the United States there is no legislation governing the co-existence of neighboring farms growing organic and GM crops; instead the US relies on a 'complex but relaxed' combination of three federal agencies (FDA, EPA, and USDA/APHIS) and the common law tort system, governed by state law, to manage risks of co-existence.:44 To limit mixing in the first stages of production, researchers and politicians are developing codes of good agricultural practice for GM crops. In addition to the thorough cleaning of machinery, recommended measures include the establishment of 'isolation distances' and 'pollen barriers'. Isolation distances are the minimum distances required between GM and non-GM cultivations for most of the GM pollen to fall to the ground before reaching non-GM plants. Pollen barriers attempt actively catch pollen, and can consist of hedges and trees which physically hinder pollen movement. Pollen barriers consisting of conventional crops of the same species as the GM crop have a special advantage, as the conventional plants not only physically limit the GM pollen flow, but also produce competitive, conventional pollen. During harvest, the buffer strip of conventional crops is considered part of the GM crop yield. In addition to agricultural measures, there may be also biological tools to prevent the genetically modified crop from fertilising conventional fields. Researchers are investigating methods either to prevent GM crops from producing pollen at all (for example male-sterile plants), or to develop GM crops with pollen that nonetheless does not contain the additional, genetically engineered material. In an example of the latter, transplastomic plants can be generated in which the genetic modification has been integrated in the DNA of chloroplasts. As the chloroplasts of plants are maternally inherited, the transgenes are not spread by pollen thus achieving biological containment. In other words, the cell nucleus contains no transgenes, and the pollen contains no chloroplasts and thus no transgenes. Two important research projects on co-existence are and Co-Extra. With the end of the de facto moratorium on genetically modified plants in Europe, several research programmes (e.g. SIGMEA, Co-Extra, and Transcontainer) have begun investigating biological containment strategies for GMOs. While SIGMEA was focused on co-existence at the farm level, Co-Extra studies co-existence along the whole production chain, and has a second focus on the traceability of GMOs, since co-existence cannot work without traceability. To be able to monitor and enforce compliance with co-existence regulations, authorities require the ability to trace, detect and identify GMOs. The development of a regulatory framework concerning genetic engineering began in 1975, at Asilomar, California. The first use of Recombinant DNA (rDNA) technology had just been successfully accomplished by Stanley Cohen and Herbert Boyer two years previously and the scientific community recognized that as well as benefits this technology could also pose some risks. The Asilomar meeting recommended a set of guidelines regarding the cautious use of recombinant technology and any products resulting from that technology. The Asilomar recommendations were voluntary, but in 1976 the US National Institute of Health (NIH) formed a rDNA advisory committee. This was followed by other regulatory offices (the United States Department of Agriculture (USDA), Environmental Protection Agency (EPA) and Food and Drug Administration (FDA)), effectively making all rDNA research tightly regulated in the USA. In 1982 the Organisation for Economic Co-operation and Development (OECD) released a report into the potential hazards of releasing genetically modified organisms into the environment as the first transgenic plants were being developed. As the technology improved and genetically organisms moved from model organisms to potential commercial products the USA established a committee at the Office of Science and Technology (OSTP) to develop mechanisms to regulate the developing technology. In 1986 the OSTP assigned regulatory approval of genetically modified plants in the US to the USDA, FDA and EPA.