Science-based Decisions on Use of Living Modified Organisms

Science-based Decisions on Use of Living Modified Organisms!

There have been many arguments that decisions on the use of these living modified organisms must be based on science; Policy may be defined when designing the system that is applied to individual applications, but that the applications should only be considered in the light of this policy.

Decisions are usually made by Government based on advice received from a number of sources. The risk assessment procedure, at the very least, should be science based. This is made very clear in the Cartagena Protocol. Article 15 states that .Risk-assessments undertaken pursuant to this Protocol shall be carried out in a scientifically sound manner.

The Parties, in reaching a decision on import under this Protocol or under its domestic measures implementing the Protocol, may take into account, consistent with their international obligations, socio-economic considerations arising from the impact of living modified organisms on the conservation and sustainable use of biological diversity, especially with regard to the value of biological diversity to indigenous and local communities.

Unlike the European Union, the US and Canada, the vast majority of developing countries may not have expertise directly employed by government in the vast array of disciplines needed to perform a complete risk assessment for transgenic organisms. The data needed to assess likely environmental degradation or impact may not be available in many countries.

A different approach may be needed, where an applicant requesting a permit for the use of a transgenic organism must perform a detailed risk assessment possibly even performing field tests in an appropriate environment and submit this for audit to a government, rather than the government performing the risk assessment.

Most scientists may feel more confident at auditing a detailed assessment than attempting the assessment themselves. Applicants could also be expected to design their own risk management, consultation and monitoring procedures, with input from government appointed assessors where appropriate. There is an obvious danger in this approach, however, for lack of trust in those applying to release organisms to provide all the necessary information may mitigate against the acceptance of the risk assessment.

Can applicants be trusted to provide all the necessary information? Where a decision is made to use audit rather than direct risk assessment by government, it is important that the scientists involved in the audit are able to ask for further information and are able to identify gaps in the approach taken by the applicant.

Risk assessment of genetically modified organism is largely based on the concept of familiarity, or of substantial equivalence.. It is actually difficult to identify other ways of approaching the problem of identifying risk. It assumes that the characteristics of the modified organism except for the specific characteristics introduced are those of the host organism. It is not easy to see any other approach, but the Royal Society of Canada and the Royal Society in the UK have both indicated dissatisfaction with substantial equivalence, which is arguably substantially equivalent to familiarity.

Crop varieties developed through conventional plant breeding techniques not involving modem biotechnologies are not generally tested for their safety. Rather they have to meet plant variety registration requirements that identify whether they are distinct from those currently on the market, uniform and stable.

These traditional methods use (primarily) crossing selection and back-crossing processes to select a desired characteristic and remove inadvertently introduced extra characteristics that initially accompany the introduced trait. These mechanisms introduce new and numerous gene combinations.

If there are toxins known to occur in these crops (e.g. glucosinolates in canola, glycol-alkaloid accumulation in potatoes), the new variety is normally tested to ensure that the level of toxin (or allergen) is no greater than the range that is normally observed for that substance.

Interactions of traits introduced by traditional methods with other characteristics of the plant are normally ignored until they prove to make the variety unusable. The implicit assumption behind this methodology is that, even where a breeding-derived novel trait is involved, new combinations of existing genes operating within highly selected germplasm are not expected to generate harmful outcomes. For transgenic crops, the concept of substantial equivalence was introduced. If a new food or food component is found to be substantially equivalent to an existing food or food component, it can be treated in the same manner with respect to safety.

In 1995, the World Health Organisation published a report in which the concept of substantial equivalence as a decision threshold was promoted as the basis for safety assessment decisions concerning GMOs.

Substantial equivalence can be considered in three ways:

1. The GM foodstuff might be regarded as substantially equivalent to its conventional counterpart both toxicologically and nutritionally. When a product has been shown to be substantially equivalent, no further safety assessment is required.

2. It might be substantially equivalent apart from certain defined differences. Sometimes the GM food product includes the components deliberately introduced by genetic modification. In this case the GM food product might be regarded as substantially equivalent to its conventional counterpart except for a small number of clearly defined differences. Assessment is then limited to examining the implications of the difference(s), perhaps by testing the novel components of the GM plant in isolation.

3. The GM product might be regarded as not substantially equivalent to its conventional counterpart, or there might not be a suitable reference available for comparison. The product will then need a highly detailed safety assessment, taking all the properties of the modified foodstuff and determining by direct measurement where necessary the impact on human health and the environment.

Many countries are deciding that the use of the term substantial equivalence is misleading. It suggests that if substantial equivalence is demonstrated, no further assessment need be done. There is a mistaken perception that the determination of substantial equivalence was the end point of a safety assessment rather than the starting point.