1、PD 6699-2:2007 Nanotechnologies Part 2: Guide to safe handling and disposal of manufactured nanomaterials ICS 13.100; 71.100.99 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW PUBLISHED DOCUMENTPublishing and copyright information The BSI copyright notice displayed in this doc
2、ument indicates when the document was last issued. BSI 2007 ISBN 978 0 580 60832 2 The following BSI references relate to the work on this Published Document: Committee reference NTI/1 Publication history First published December 2007 Amendments issued since publication Amd. no. Date Text affected P
3、D 6699-2:2007 BSI 2007 i PD 6699-2:2007 Contents Foreword ii 1 Scope 1 2 Manufactured nanomaterial types and characteristics 1 3 Nanoparticle exposure and risk 3 4 General approach to managing risks from nanoparticles 6 5 Identification and competence of person conducting risk assessment 7 6 Informa
4、tion collection 8 7 Risk evaluation 8 8 Control of exposure 11 9 Health surveillance 16 10 Measurement methods for evaluating controls 17 11 Spillages and accidental releases 20 12 Disposal procedures 21 13 Prevention of fire and explosion 23 Bibliography 24 List of figures Figure 1 Approach to mana
5、ging risks from nanoparticles 7 Figure 2 Hierarchy of control 11 Figure 3 Suggested control approaches for various generic tasks 15 List of tables Table 1 Devices for direct measurement of number, mass and surface area concentration (adapted from PD/ISO TR 27628) 18 Table 2 Devices for indirect meas
6、urement of number, mass and surface area concentration (adapted from ISO 2007) 18 Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages 1 to 26, an inside back cover and a back cover.PD 6699-2:2007 ii BSI 2007 Foreword Publishing information This Publis
7、hed Document is published by BSI and came into effect on 31 December 2007. BSI Committee NTI/1, Nanotechnologies, takes collective responsibility for its preparation. The Committee wishes to acknowledge the contribution of SAFENANO at the Institute of Occupational Medicine in preparing this Publishe
8、d Document. A list of organizations represented on the Committee can be obtained on request to its secretary. This Published Document was commissioned by the UK Department for Innovation, Universities and Skills (DIUS) to provide guidance for manufacturers and users of nanoparticles on their proper
9、handling and disposal in order to minimize the risk from known, and as yet unknown, health and environmental hazards associated with such materials. Use of this document As a guide, this Published Document takes the form of guidance and recommendations. It should not be quoted as if it were a specif
10、ication and particular care should be taken to ensure that claims of compliance are not misleading. It has been assumed in the preparation of this Published Document that the execution of its provisions will be entrusted to appropriately qualified and experienced people, for whose use it has been pr
11、oduced. Presentational conventions The provisions in this Published Document are presented in roman (i.e. upright) type. Its recommendations are expressed in sentences in which the principal auxiliary verb is “should”. The word “may” is used in the text to express permissibility, e.g. as an alternat
12、ive to the primary recommendation of the clause. The word “can” is used to express possibility, e.g. a consequence of an action or an event. Contractual and legal considerations This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its cor
13、rect application. This Published Document is not to be regarded as a British Standard. BSI 2007 1 PD 6699-2:2007 1 Scope This Published Document gives guidance on assessing risks and recognizing uncertainties in the development, manufacture and use of nanomaterials, and on developing and implementin
14、g an effective strategy to address and control the risks. It is applicable to a wide range of nanomaterials and nanostructured materials as defined in PAS 136, including nanoparticles, nanofibres, nanopowders, nanotubes and nanowires, generically referred to as nano-objects, as well as aggregates an
15、d agglomerates of these materials. It also covers any material or preparation in which such nanomaterials comprise a significant proportion. This guide is not applicable to incidentally produced nanoparticles, such as diesel exhaust and welding fumes. NOTE For the purposes of this guide the terms na
16、noparticle and nanomaterial are used interchangeably to refer to all of the nanomaterial types listed above. This Published Document recognizes that there is considerable uncertainty about many aspects of effective risk assessment of nanomaterials, including the hazardous potential of many types of
17、nanoparticles and the levels below which individuals might be exposed with minimal likelihood of adverse health effects. The guide therefore recommends a cautious strategy for handling and disposing of nanomaterials. 2 Manufactured nanomaterial types and characteristics 2.1 General This clause descr
18、ibes some of the more common types of manufactured nanomaterials to which this guide may be applied. It is not intended to be a full and comprehensive guide to nanoparticle types. 2.2 Fullerenes Fullerenes comprise one of four types of naturally occurring forms of carbon, first identified in the 198
19、0s 1. Their molecules are composed entirely of carbon and take the form of a hollow sphere or a tube. Fullerenes are similar in structure to graphite which comprises a sheet of hexagonal carbon rings, but contain pentagonal or heptagonal rings which enable 3D structures to be formed. The best known
20、fullerene is C 60 , often referred to as a buckminsterfullerene or a buckyball. Fullerenes are chemically stable materials and insoluble in aqueous solutions. Potential applications include drug delivery, coatings, lubrication and hydrogen storage (PAS 136).PD 6699-2:2007 2 BSI 2007 2.3 Carbon nanot
21、ubes Carbon nanotubes (CNTs) are a specific form of fullerenes, first reported by Iijima 2. They are similar in structure to C 60but are elongated to form tubular structures a few nm in diameter. They can be produced with very large aspect ratios and can be more than 1 mm in length. In their simples
22、t form, CNTs comprise a single layer of carbon atoms arranged in a cylinder, known as single-wall carbon nanotubes (SWCNTs). They can also be formed as multiple concentric tubes (multi-wall carbon nanotubes, MWCNTs) with diameters up to 20 nm, and length greater than 1 mm. CNTs have great tensile st
23、rength and are considered to be 100 times stronger than steel, whilst being only one sixth of its weight. They also exhibit high conductivity, high surface area, unique electronic properties, and potentially high molecular adsorption capacity 3. They are chemically stable materials and insoluble in
24、aqueous solutions. Potential applications include coatings, composites, electronics, water purification and construction materials. 2.4 Nanowires Nanowires are small conducting or semiconducting nanoparticles with a single crystal structure, a typical diameter of a few 10s of nm and a large aspect r
25、atio. Various metals have been used to fabricate nanowires, including cobalt, gold and copper. Silicon nanowires have also been produced. Potential applications include inter-connectors in nano-electronic devices, photovoltaics and sensors. 2.5 Quantum dots Quantum dots are small (2 nm to 10 nm) ass
26、emblies of semiconductor materials with novel electronic, optical, magnetic and catalytic properties. Typically containing 1 000 to 100 000 atoms, quantum dots are considered to be something between an extended solid structure and a single molecular entity. Semiconductor quantum dots exhibit distinc
27、t photo-electronic properties which relate directly to their size. For example, by altering the particle size the light emitted by the particle on excitation can be tuned to a specific desired wavelength. Applications include catalysis, medical imaging, optical devices and sensors. 2.6 Other nanopar
28、ticles This category includes a wide range of spherical, aggregated or agglomerated forms of nanoparticles, including ultrafine carbon black and fumed silica, which are synthesized in bulk form through flame pyrolysis methods. Such nanoparticles can be formed from many materials, including metals, o
29、xides, ceramics, semiconductors and organic materials. They can be composites having, for example, a metal core with an oxide shell, or alloys in which mixtures of metals are present. This group of nanoparticles is generally less well defined in terms of size and shape, and likely to be produced in
30、larger bulk quantities than other forms of nanoparticles. Applications include coatings and pigments, catalysis, personal care products, cosmetics and composites. BSI 2007 3 PD 6699-2:2007 3 Nanoparticle exposure and risk 3.1 General It has been established for many years that exposure to particles,
31、 including nanoparticles, can cause ill health in individuals or exposed populations. There are many instances of this relating to exposure from industrial activity and environmental pollution. For example, in an occupational setting, exposure to coal dust is clearly linked to the onset of lung dise
32、ases, such as pneumoconiosis and chronic obstructive pulmonary disease (COPD), and exposure to asbestos is clearly linked with asbestosis, mesothelioma and lung cancer. In an environmental context, recent evidence has suggested that exposure to the particulate component of atmospheric pollution, mig
33、ht be associated with increased hospitalization rates and cardio-vascular disease. However, many millions of the population are exposed to particles in environmental pollution on a daily basis without any apparent ill effects. For any material, the risk, or likelihood, of illness increases with incr
34、easing dose. Dose broadly refers to “how much” gets to an organ where disease occurs and “how long” it stays there. Toxicity, specifically for relatively insoluble particles, appears to relate to the total surface area of the particles. 3.2 Potential risks to health from inhalation of nanoparticles
35、More than 30 major reviews and position papers have discussed the potential risks to health and to the environment from exposure to nanoparticles 4. The potential risks to health from inhalation of nanoparticles may be summarized as follows. a) Due to their small size, nanoparticles can reach parts
36、of biological systems which are not normally accessible by larger particles. This includes the increased possibility of crossing cell boundaries or of passing directly from the lungs into the blood stream and so on to all of the organs in the body, or even through deposition in the nose, directly to
37、 the brain. This process is known as translocation and, in general, nanoparticles can translocate much more easily than other, larger particles. b) Due to their small size, nanoparticles have a much higher surface area than the same mass of larger particles. If surface area is a driver for toxicity
38、this clearly implies potentially increased toxic effects. c) For some nanomaterials, reduction in size has been shown to relate to increased solubility. This effect might lead to increased bioavailability of materials which are considered to be insoluble at larger particle sizes. d) An important rat
39、ionale for developing nanomaterials and nanoparticles is that they will have new and different properties to larger particles of the same material. Altered chemical and/or physical properties might be expected to be accompanied by altered biological properties, some of which could imply increased to
40、xicity. PD 6699-2:2007 4 BSI 2007 e) A specific issue relates to comparisons between high aspect ratio nanoparticles (e.g. some forms of carbon nanotubes or nanowires) and asbestos. Asbestos has a fibrous nature with high aspect ratio (the ratio of length to diameter). Some fibrous particles cause d
41、isease because they can be inhaled and enter the alveolar region of the lung and are not easily removed because (i) their physical dimensions mean they cannot be removed by lung clearance mechanisms and (ii) they are highly durable and do not dissolve in the lung lining fluids. Hence they remain in
42、the lung for a long period of time, causing inflammation and ultimately disease. Some high aspect ratio nanoparticles can have similar morphology (shape) and durability and are therefore likely to persist in the lungs, if inhaled. Along with increasing production volumes, lower costs and an increase
43、d general prevalence of these materials in industry and commerce, these issues indicate that more needs to be done to assess the potential risks associated with these nanomaterials and that a suitably cautious approach should be taken in their handling and disposal. The likelihood (or risk) of disea
44、se occurring depends on the dose of the particles in the organ where disease can occur, and the toxicity of nanoparticles. Dose cannot be assessed directly, but can be inferred from the exposure to nanoparticles, which is a combination of the concentration of particles in the air which a person brea
45、thes in and the length of time the exposure lasts. If there is no exposure (i.e. no nanoparticles in the air), no dose will accumulate and, despite the potential toxicity of the particles, there will be no risk to health. It therefore follows that an appropriate response to the risks from nanomateri
46、als is to understand the potential exposures which could arise from the manufacture and use of nanomaterials and to put in place measures to mitigate, manage or reduce exposure. In this way the risks can be controlled. 3.3 Potential nanoparticle risks to health from dermal exposure or ingestion Conc
47、erns have also been raised about the potential risks to health arising from dermal exposure to some types of nanoparticles, based on the possibility of these materials penetrating the skin and entering the bloodstream. To date, though, there have been very few studies of this effect 5, 6 and these h
48、ave not demonstrated skin penetration by nanoparticles to any extent. However, the studies are preliminary and have not considered, for example, the effect of damaged skin. Other studies are currently under way but, until consensus emerges, a prudent approach would be to limit exposure to the skin.
49、Potential heath effects due to ingestion have also been postulated based on the possibility of nanoparticle transfer across the gastro-intestinal wall. Again, however, there is presently no direct evidence that any occupational ill heath is caused by this effect, but it would be prudent to minimize exposure by this route. BSI 2007 5 PD 6699-2:2007 3.4 Nanoparticles as hazardous materials Current guidance indicates that a hazardous material may be identified as follows 7. a) It may be listed in publications, such as the UK Health and Safety E
