Guidance- Risk Management Approaches
Working with nanoparticles
At the current point in time, there is no single piece of guidance which can provide a step-by-step approach to safe and responsible working with nanoparticles. This is not surprising given the vast range of materials with widely different properties which may be included in the definition, and the generally recognised lack of knowledge about their properties. We have not attempted to develop such a guide here, rather we have tried to map out some general principles which would if properly applied lead towards safe and responsible working. We have also tried toenhance this by providing links to downloads of some useful relevant documents.
1. Do a risk assessment
Just like working with any other chemicals, a risk assessment should be the first step in ensuring that work activities which use nanoparticles are appropriately and effectively controlled. The precautions needed will be identified through a suitable risk assessment. At a basic level, a risk assessment compromises a series of steps and actions to:
1. Identify the hazards
2. Decide who might be harmed and how
3. Evaluate the risks and decide on precautions and
4. Record the findings and implement them.
5. Risk assessments should always be reviewed and updated in light of new information or as necessary, and at regular intervals.
2. Have a structured approach towards control
In the UK, the law relating to use of chemicals or other hazardous substances at work requires employers to control exposure to hazardous substances to prevent ill health. They have to protect both employees and others who may be exposed by complying with the Control of Substances Hazardous to Health Regulations (COSHH) 2002 which are based around this risk assessment approach. COSHH provides a good framework for thinking about and managing the potential risks from nanomaterials. The COSHH framework identifies eight main steps which are:
1. Assess the risks
2. Decide what precautions are needed
3. Prevent or adequately control exposure
4. Ensure that control measures are used and maintained
5. Monitor the exposure
6. Carry out appropriate health surveillance.
7. Prepare plans and procedures to deal with accidents, incidents and emergencies
8. Ensure employees are properly informed trained and supervised
The Principles of Good Practice for the Control of Exposure can also be applied to work with nanoparticles. The principles of good practice for the control of exposure to substances hazardous to health are set out in the COSHH ACOP. A summary of these is given below:
A. Design and operate processes and activities to minimise emission, release and spread of substances
hazardous to health;
B. Take into account all relevant routes of exposure - inhalation, skin absorption and ingestion - when
developing control measures;
C. Control exposure by measures that are proportionate to the health risk;
D. Choose the most effective and reliable control options which minimise the escape and spread of
hazardous substances
E. Where adequate control of exposure cannot be achieved through other mean, provide, in combination
with other control measures, suitable personal protective quipment;
F. Check and review regularly all elements of control measures for their continuing effectiveness;
G. Inform and train all employees on the hazards and risks from the substances with which they may work
and the use of control measures developed to minimise risk;
H. Ensure that the introduction of control measures does not increase the overall risk to health and safety.
More detail about COSHH and the Health and Safety Executive (HSE) approach to risk assessment can be found
here.
3. Be suitably cautious
One of the difficulties in applying a COSHH approach to nanoparticles is that the information available may be incomplete or worse, incorrect. COSHH relies on having good information about the hazardous nature of materials, the effectiveness of control approaches and easy ways to monitor exposure. However, as has been identified in more than 25 major international reviews since 2004, there are significant gaps in knowledge and understanding about just these issues for nanoparticles. In fact, the EC Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) stated in 2005 "there is insufficient knowledge...to allow for satisfactory risk assessments for populations and ecosystems to be performed"
HSE in published their last guidance on nanoparticle risk issues in 2004. Their Horizons Scanning Information Note No HSIN1 can be downloaded
here.
In this note the HSE provide the following advice "Risk assessment should be undertaken using both sound scientific information and past experience. Due to the developmental nature of much of nanotechnology this information may be incomplete. However you should make thorough enquiries to obtain as much information as possible. Where significant gaps in knowledge remain, your risk assessment and risk management decisions should be suitably cautious, providing higher levels of protection as the significance and level of uncertainty about the risk increases." In our view it is inappropriate to assume that a nanoparticle form of a material had the same hazard potential as the macro form.
4. Minimise exposure
For most particulate materials that can become airborne and be breathed in, particularly those that are poorly soluble, the primary health concern is for effects on the lung. This should be the first consideration for any particle that you are using, where there is any potential for inhalation exposure. However, you should also consider other means of exposure, such as skin contact or ingestion. The absence of knowledge about the health hazards of new nanomaterials introduces significant uncertainty into any risk assessment. You should therefore implement stringent controls on exposure when working with them.
5. Consider risks from explosion
There is almost no data relating to the fire and explosion hazards of nanoparticles. While it is unlikely that very small amounts of material will create a risk, larger amounts of combustible powder could. Nanoparticulate products could be raised from a layer into suspension more easily than coarser products, and may remain in suspension for a long time. Dense clouds of nanoparticle powder may be difficult to see, even though a suspension of the same product at the same concentration at a coarser grade is easily visible. If your nanoparticulate is composed of combustible materials it is likely to pose such a hazard.
Further information about the risks of explosion is available from HSE. Safe handling of combustible dusts: Precautions against explosions HSG103 (Second edition) HSE Books 2003 ISBN 0 7176 2726 8.
6. Take steps to address the knowledge gaps
HSIN1 recommends "you should also take steps e.g. initiate further focused research, to address the gaps in information to allow your risk assessment to be refined. Risk assessments should be reviewed on a regular basis and whenever new information becomes available."
The primary objective of SAFENANO is to help to fill in these information gaps with the latest knowledge about nanoparticle risk issues.
7. A life cycle approach for manufacturers
Organisations involved in the manufacture, supply or use of any material carry a duty to understand the risks that the material may pose not just to the health of their workforce but also to their customers and to the environment, and to put in place such measures that are needed to manage these risks. This requires them to address the gaps in knowledge to gain a better understanding of the risks associated with these materials than they currently have, whether it is to comply with regulation, pre-empt potential regulation or demonstrate responsibility.
DuPont and Environmental Defence intend to publish their risk management framework in June 2007, this will be one of the first integrated frameworks to address the risks and responsibilities for manufacturers. The intent of this Framework is to define a systematic and disciplined process for identifying, managing, and reducing potential environmental, health, and safety risks of engineered nanomaterials across all stages of a product's "lifecycle" - i.e. its full life from initial sourcing through manufacture, use, disposal, and ultimate fate. The Framework offers guidance on the key questions an organisation should consider in developing applications of nanomaterials, and on the information needed to make sound risk evaluation and risk management decisions. The Framework allows users flexibility in making such decisions in the presence of knowledge gaps - through the application of reasonable assumptions and appropriate risk management practices. Furthermore, the Framework describes a system for guiding information generation and updating assumptions, decisions, and practices with new information as it becomes available. Finally, it offers guidance on how to communicate information and decisions to key stakeholders.
The utility of this framework has yet to be demonstrated and there are detailed aspects of it which SAFENANO does not necessarily support, however it is an important contribution. A draft version on this Framework is available
here.
Other useful guidance