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What is meant by 'risk'?
In general, risk is defined as the product of the chance of an undesirable event and the frequency (estimated or actual) of that event. This results in an estimate of the scope of the effect that can be used to determine whether, and how, the risks should be taken into consideration during discussions about risk management. For example the production of a vaccine, consisting of dead bacteria, that can protect children of whooping cough. An undesirable effect during culturing would be the spread of living bacteria. This could result in the infection of someone in the vicinity, who may then fall ill. Measures to prevent spread during the production phase are one example of risk management. In this example, the risk depends on the following factors.
a) The possibility of the bacteria being released from culture flasks.
b) The numbers released.
c) The possibility of survival of the bacteria.
d) The possibility that a child or adult may be infected.
The definition of the risk is the first stage, followed by estimation of the possibilities to take precautionary measures to limit the risk. The risk can be thought of as the product of the individual possibilities a, b, c and d. By taking proper security precautions, the possibilities under a and b can be kept to a minimum, resulting in a considerable reduction of the risk. The risk is not eliminated completely, even though there have been no accidents in recent decades while producing the vaccine in question. Theoretically, the risk will never be eliminated completely. This is a basic principle of every risk analysis, irrespective of the area covered by the risk assessment.
Limiting risk, increasing safety
In general, when handling living organisms, risk-limitation precautions are taken on two different levels. These precautions are based on the physical and biological confinement of the organisms.
Physical containment
The physical confinement of living organisms is based on a reduction of the possibility of undisered contact between organisms. This is done by "containing " the organism. The possibility of release can be reduced by cutting off the escape routes. A range of measures is possible and the list below includes only some examples.
a) Culturing bacteria in closed flasks.
b) Working in a sealed area, possibly using filters to purify outgoing air.
c) Wearing special clothing that is left behind in the room.
d) Sterilising all materials that may be contaminated.
Not all bacteria are equally dangerous when they are released from the confined area. Our environment contains an enormous variety of harmless bacteria not dangerous for people or the environment. Only a limited number of bacteria are harmful for people or the environment. These bacteria can cause illness or even death when people, animals or plants become infected. That is why there are different levels of confinement. The more dangerous the type of bacteria, the stricter the requirements for the area where handling of these bacteria take place.
In the Netherlands, we distinguish between four levels with increasing physical containment: ML-I, ML-II, ML-III and ML-IV. The requirements become progressively more stringent, as shown in the table below.
| Containment regulations | ML-I | ML-II | ML-III | ML-IV |
| Permanent working area | + | + | + | + |
| Work surface, floors, walls and doors should be made from non-absorbent material and be easy to clean. | + | + | + | + |
| Enough space between workbenches | + | + | + | + |
| Equipment in good condition | + | + | + | + |
| Sink present in the working area | + | + | ||
| A sink present in the airlock | + | |||
| Complete change of clothes and shower obligatory | + | |||
| Access to the working area via a closable door | + | + | + | |
| Biohazard sign on access door | + | + | + | |
| Names and telephone numbers of at least one responsible person and the biological safety officer should be on access door | + | + | + | |
| Windows cannot be opened | + | + | + | |
| Autoclave present in the same building as the working area | + | + | ||
| Autoclave present in the working area | + | |||
| A class II or III safety cabinet is present in the working area | + | + | + | |
| The floor covering, including the corners and skirting sections, is seamless | + | + | ||
| The air in the working area is removed through a separate air duct | + | + | ||
| Vacuum lines have a hydrophobic absolute filter | + | + | ||
| The working area must not be located in the vicinity of areas where there is a danger of fire, explosions or flooding | + |
Table 1: Overview of a number of containment regulations for various working areas. The containment regulations stated here are listed in the Dutch Ministerial Order GMO. It should be pointed out that the table above only shows a selection of regulations from the Order. For full information, it will therefore be necessary to consult the Order.
Biological containment
For research purposes, organisms are generally used that depend for growth on specific laboratory conditions. As a result, these organisms cannot survive outside the laboratory. This factor is of major importance for the protection of people and the environment.A few examples:
Escherichia coli is an intestinal bacteria that can cause illnesses such as diarrhoea. Despite this, a particular strain of this bacteria, E. coli K12, has now been used for many decades in laboratories in large quantities without any incidents. This laboratory strain has lost the ability to establish itself in the intestine, the sine qua non of the disease process. The same defect in the strain is also the reason why the bacteria can no longer compete with other bacteria in the intestine. The strain has therefore lost its pathological properties and it will be virtually incapable of reproducing in its normal niche (the intestine).
Bacillus subtilis is, just like E. coli, used extensively in the laboratory. It is a soil organism that is capable of forming spores that can survive under extreme conditions like shortage of nutrients. The spores can germinate when the conditions are suitable, for instance when food supplies return. The Bacillus subtilis strains generally used in the laboratory are not capable of forming spores so that the possibility of these strains surviving outside the laboratory is slim.
Many organisms used in day-to-day practice in the laboratory have properties that preclude survival outside the laboratory. They have only a limited possibility of survival and dissemination after release.
Risk assessment
The COGEM's task is to advise on the risks for people and the environment associated with all activities with genetically modified organisms, and on the safety precautions required.
The COGEM has identified the factors that play a role in the process of risk assessment. The general process of risk analysis consists of the following stages:
1-The identification and characterisation of possible risks
This involves the identification of the properties of the genetically modified organism that may have a negative impact on the environment and on human and animal health. The estimate is based on the properties of the host and the modified DNA. The aim is a qualitative and quantitative evaluation of the nature of the negative effect.
2-Evaluation of the scope of the effect
This involves making estimates of the exposure of people, animals and the environment. Some of the factors taken into consideration are: i) survival in the environment, ii) occupation of an ecologic niche iii) interaction with other organisms and iv) frequency of transfer of genetic material. These factors are examples of aspects that may play a role in the assessment of the exposure or degree of dissemination of a genetically modified organism (GMO) in the environment. Factors of this kind can have an effect on the scope of any possible impact.
3-Risk evaluation
This involves a qualitative and, where possible, a quantitative estimate of the possibility that negative effects may occur in a population, sub-population or ecosystem.
4-Risk management
Risk management is the process in which, on the basis of the results of the risk assessment, the desired control measures are selected.
The COGEM makes an assessment of the risks associated with work using genetically modified organisms on the basis of scientific technical recommendations. This assessment is submitted to the Minister of Housing, Spatial Planning and the Environment in the form of an advisory report. Using this system, the control measures were gradually established on the basis of the risk assessment for the purposes of confined use and included in the classification sections of the Ministerial Order GMO (the Ministerial Order). The control measures for applications for deliberate release into the environment can be found in the recommendations produced for each case. All these control measures have, over the years, been adapted on the basis of new scientific understanding. The systematic risk analysis is therefore still under development.
5-Communication about risks
Communication about risks between risk assessors, the people involved in the work requiring risk management and outsiders who are sometimes confronted directly with the consequences of the work like local residents, consumers and other stakeholders, is of major importance. That is why a constant exchange of information is a pre-condition for sound decisions. Therefore, representatives of the COGEM have frequent contacts with the GMO Office and the Ministry of Housing, Spatial Planning and the Environment.
The COGEM can, where necessary, provide advice about the risk management and monitoring measures needed during work with GMOs. However, there are policy issues involved in the question of whether, and in what conditions, work of this kind can or should take place. It is most definitely not the task of the commission to deal with policy issues of this kind. The Minister of Housing, Spatial Planning and the Environment takes the ultimate decisions.
The COGEM has not a leading role in informing the public about risks (information activities). It plays a supporting role in this respect, as a supplier of information, facilitating from a scientific background the discussion about genetically modified organisms.