Experience Sharing of an Evolving Nanosafety Program at a Research University. Dr Samuel Yu, DEnv,, CIH Dr Joseph Kwan, DEnv,, CIH SEPO HKUST

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1 Experience Sharing of an Evolving Nanosafety Program at a Research University Dr Samuel Yu, DEnv,, CIH Dr Joseph Kwan, DEnv,, CIH SEPO HKUST

2 Hong Kong University of Science and Technology (HKUST) started in schools, 9000 students, 453 faculty members 05/06 research funding 31M USD (not including faculty salary) EHS Office established Day 1, now 22 staff including an AIHA accredited IH Lab

3 Outlines Potential hazard Nanoresearch at HKUST Elements of nanosafety program at HKUST Assessment of exposure potential Destruction experiment Lessons learned Challenges and opportunities

4 Potential Hazards

5 Different Nano-Related Materials Nanoparticles (d<100 nm) & nanomaterials with one extended dimension, e.g. nanotube, nanowire, nanofiber Nanocomposite,, e.g. CaCO 3 /PP composite Materials with engineered nanostructure, e.g. zeolite with designed nano-size pores Silicon-based nanostructure, nanoelectronics Nano-enabled products Nano-stuff

6 Different Forms of Hazards Nanoparticles Agglomerates Aerosolized suspension (slurry, solution) Comminution (crushing, grinding, machining of nanomaterials) Degradation or failure Unintentional use

7 Origins of Nanoparticles Naturally occurring, e.g.volcanic activities, wild fires Anthropogenic incidental nanoparticles, e.g. engines, incinerators Also known as ultrafine particles, <100 nm in AED Engineered nanoparticles At least one dimension <100 nm Relatively uniform in size, monodispersed

8 Unique Properties of Engineered Nanoparticles Novel physicochemical properties not found in parent materials Much higher reactivity, both chemical and biological Precisely designed molecules for specific purposes

9 Risk Assessment Precautions Nanomaterials should be considered potentially hazardous until proven otherwise Nanomaterials possess unique physical chemical properties, should be treated as new chemicals MSDS of raw material can only be viewed as a starting point at best Example: Carbon practically non-toxic, buckyballs (C 60 ) oral LD 50 = 300 mg/kg

10 Main Concerns Airborne particles considered most crucial for worker protection Liquid phase may present skin hazard Suspended fine powder can become a fire and explosion hazard Natural agglomeration of nanoparticles, but researchers and users trying to disperse nanoparticles for various applications Both phases may impact the environment

11 Nanoresearch at HKUST

12 Carbon-based based Nanomaterials-- Fullerenes The 3 rd form of pure carbon other than - diamond and graphite Repeating hexagonal and pentagonal rings of carbon atoms Include Buckyballs (C 60 ) and other spherical structures, single wall and multi- wall nanotubes (SWNT, MWNT)

13 Fullerenes Source:

14 Fullerene Generation by Arc Discharge Reaction Chamber Graphite Rods and Powder

15 Purification of Fullerenes

16 Derivatization of Nanofiber

17 Carbon Nanotube by Chemical Vapor Deposition

18 Nanosized Metal and Metal Oxides TiO 2 for photochemical oxidation, self- cleaning paints, etc ZnO in cosmetics, sunblock Fe for oxidation of contaminants in groundwater CuO for antimicrobial agent Fe 2 O 3 as contrast agent for MRI CdSe as quantum dots

19 Nano-sized Zinc Oxide

20 Iron Platinum Nanoparticles

21 Quantum Dots (Q-Dots) Nanoparticles of semiconducting materials, such as CdSe core with ZnS Shell Size so small it interfere with quantum behavior of atoms Display tunable absorption and emission spectrum over visible wavelength Strong potential for medical imaging

22 overview.html

23 Quantum Dots Conjugate Used as Fluorescence Label Xenopus muscle cells grown on circular coverslip Procedures Dilution of conjugate (1:400) Labeling at room temp, 20 µl L per coverslip Contact 3 to 30 minutes on a shaker Washing with buffer Observation with fluorescent microscope Advantage: Qdot does not bleach over time like traditional fluorescence

24 Synthetic Zeolite Hydrated alumino-silicate, porous material Both natural and synthetic Porous structure allow interesting chemistry Synthesis can be fine-tuned to produced desired nanostructure Potential applications as catalyst, fuel cell etc

25 Synthetic Zeolite

26 Elements of Nanosafety Program at HKUST

27 Nano, or Otherwise

28 Scope of Nanosafety Program Nanoparticles (d<100 nm) & nanomaterials with one extended dimension, e.g. nanotube, nanowire, nanofiber Nanocomposite,, e.g. CaCO 3 /PP composite Materials with engineered nanostructure, e.g. zeolite with designed nano-size pores Silicon-based nanostructure, nanoelectronics Nano-enabled products Nano-stuff

29 Preliminary Nanosafety Program at HKUST Safety input to Nanolab facility Nanosafety in research proposal review Precautionary measures Nanomaterial database Assessment of exposure potentials Nanosafety training Monitoring of nano-ehs development

30 Inputs to NanoLabs New research facility safety review in place Institute of Nanomaterial and Nanotechnology operation from 2003 Small facility ~300 m 2 Typical wet chemistry lab with fumehoods Recommendation from EHS to consider fumehood with HEPA or BSC for handling nanomaterial with airborne potential

31 Research Proposal Review Part of Ethics Review, required for all proposals before sending to funding sources PI to declare use conditions of human subjects, animals, hazardous agents and applicable controls Safety review panel includes EHS staff and faculty members EHS notified to follow up once project is funded

32 Nanosafety Section Added New section on Nanosafety added to Research Proposal Review Form in late 2005 PI to declare use of nanomaterials Chemical nature Known toxicity Use conditions (e.g. airborne, skin contact) Control measures Environmental release and justification Disposal and verification

33 Precautionary Measures Issued in Mar 2007, mainly for engineered nanoparticles Main references Approaches to Safe Nanotechnology: An Information Exchange with NIOSH. National Institute for Occupational Safety and Health, July dfs/approaches_to_safe_nanotechnology_28novemb er2006_updated.pdf Nanoscience and nanotechnologies: opportunities and uncertainties.. The Royal Society & Royal Academy of Engineering, July

34 Precautionary Measures Risk Assessment & Practice (1) Reiterate risk assessment precautions Treat as potentially hazardous Consider as new chemical Airborne particles Avoid aerosol generation Use local exhaust ventilation Use HEPA for protection

35 Precautionary Measures Risk Assessment & Practice (2) Liquid solution/suspension Avoid aerosol generation Avoid skin contact Use gloves at least protective against carrier solvent Waste disposal Treat as chemical waste as a minimum Seek to remove from waste stream or destruct nanofeature

36 An Applied Study of Destructing Nanofeature of Quantum Dots

37 Quantum Dots Toxicity We have not investigated the toxicity of the Qdot streptavidin conjugate. The materials are provided in a solution which is ~2 mm total Cd concentration; however, the CdSe core is encapsulated in a shell of ZnS and the polymer shell, which may prevent dissolution of free Cd. We have demonstrated the utility of these materials in a variety of live-cell in vitro labeling experiments, but do not have systematic data investigating the toxicity of the materials to humans, to animals, or to cells in culture. Source: Qdot Streptavidin Conjugates User Manual, Intrivogen

38 Quantum Dots Disposal The Qdot conjugate contains cadmium and selenium in an inorganic crystalline form. Please dispose of the material in compliance with all applicable local, state, and federal regulations for disposal of these classes of material. For more information on the composition of these materials, consult the Material Safety Data Sheet. Source: Qdot Streptavidin Conjugates User Manual, Intrivogen

39 Qdot Destruction Experiment Tried different concentrations of HCl and HNO 3 to dissolve Qdots Use fluorescence wavelength under microscope to verify destruction May need to use TEM as confirmation Disposed as waste metal solutions may not destruct nano-feature

40 Acid-Treated QDot Solution

41 Nanomaterial Database Systematic information gathering Capture new items at proposal review and field visits Record novel & commercial materials Contain nature of nanomaterial and usage procedures Record preliminary hazard assessment and control measures

42 Assessment of Exposure Potential

43 Field Instruments P-Trak 0 5x10 5 particle/cm 3 20 nm 1 µm Dust-Trak mg/m µm

44 Check by BSC A properly functioning Class II biological safety cabinet Double check zeroing of meters Outside: 1200 pt/cc, mg/m 3 Inside: 0 pt/cc, mg/m 3

45 Weighing of Halloysite for Nanocomposite work Halloysite nanotube, a natural clay mineral, alumino-silicate Dia <100 nm, µm m long Open top balance Bkgd: : 3400 pt/cc, mg/m 3 Process: 3420 pt/cc, mg/m 3

46 Weighing of Carbon Nanofiber for Derivatization Work Carbon nanofiber, dia nm Top-loading electronic balance Bkgd: : 1870 pt/cc, mg/m 3 Process: 1720 pt/cc, mg/m 3

47 Copper Nanowire by Chemical Vapor Deposition Grow Cu nanowire on wafer in tube furnace, under H 2 Inside fumehood Bkgd: : 1970 pt/cc, mg/m 3 Process: 2020 pt/cc, mg/m 3

48 Mechano-chemical chemical Synthesis of Nanosize Zinc Oxide (1) Using an enclosed ball milling machine Nanosize ZnO formed in paste form Bkgd (1): 411 pt/cc, mg/m 3 Running of machine: 415 pt/cc, mg/m 3

49 Mechano-chemical chemical Synthesis of Nanosize Zinc Oxide (2) Bkgd (1): 411 pt/cc, mg/m 3 Reaction chamber opened: 473 pt/cc, mg/m 3 Bkgd (2): 1050 pt/cc, mg/m 3 Process end: 1060 pt/cc, mg/m 3

50 Chemical Vapor Deposition Synthesis of Nanosize ZnO (1) Process in tube furnace Bkgd: : 2310 pt/cc, mg/m 3 Opening of furnace after cooling: 2290 pt/cc, mg/m 3

51 Chemical Vapor Deposition Sythesis of Nanosize ZnO (2) Bkgd: : 2310 pt/cc, mg/m 3 Removal of metal foil with ZnO: : 2250 pt/cc, mg/m 3 Transfer ZnO to filter paper in Petri dish: 2180 pt/cc, mg/m 3

52 Synthesis of Fullerene by Arc- Discharge (1) Custom-made made reactor Use graphite powder as stock Arc-discharge under nitrogen

53 Synthesis of Fullerene by Arc- Discharge (2) Bkgd: : 2100 pt/cc, mg/m 3 Opening reactor & collecting product in bag: 2410 pt/cc, mg/m 3 (1 min), 2.53 mg/m 3 (max) Transferring from bag to filter paper: 2370 pt/cc, 1.56 mg/m 3 (1 min), 6.10 mg/m 3 (max)

54 Previous Exposure Monitoring In 2001 for fullerene generation Personal <0.01 mg/m 3 (60 mins) Area 0.16 mg/m 3 (60 mins) In 2002 for opening and cleaning of reactor Personal 2.3 mg/m 3 (60 mins) Area 0.91 mg/m 3 (60 mins) In 2006 for fullerene generation Personal 0.11 mg/m 3 (300 mins) Area (x2) 0.12 and 0.09 mg/m 3 (300 mins) Particulate TLV used as reference Recommended particulate respirator

55 Forming Nanosize CaCO 3 /PE Composite by Extruder (1) Lab scale extruding machine Nanosize CaCO 3 (10nm 1 µm) added as filler to polypropylene (PP) 10g of CaCO 3 in 200g PP

56 Forming Nanosize CaCO 3 /PE Composite by Extruder (2) Bkgd (1): 2100 pt/cc, mg/m 3 Weighing of nanosize CaCO 3 by electronic balance: 1949 pt/cc, mg/m 3 Bkgd (2): 2800 pt/cc, mg/m 3 Feeding nanosize CaCO 3 and PP into extruder: 2572 pt/cc, mg/m 3

57 Forming Nanosize CaCO 3 /PE Composite by Extruder (3) Bkgd (2): 2800 pt/cc, mg/m 3 Extruding composite, inside canopy hood: 2150 (ave( ave), 5110 (max) pt/cc (ave( ave), (max) mg/m 3 Outside canopy hood: 1985 (ave( ave), 2400 (max) pt/cc (ave( ave), (max) mg/m 3

58 Forming Nanosize CaCO 3 /PE Composite by Extruder (4) Bkgd (2): 2800 pt/cc, mg/m 3 Cleaning extruder by air gun, outside canopy hood: 3455 (ave( ave), 7270 (max) pt/cc (ave( ave), (max) mg/m 3

59 Nanosafety Training & Monitoring Nano-EHS Development Nanosafety integrated into new Chemical Safety Training curriculum Refresher for existing chemical users New nanosafety chapter added to Safety Manual Continuous monitoring of Nano-EHS development Revise and disseminate update information

60 Lessons Learned

61 Lessons Learned Managing Nanoresearch Capture information at proposal stage Take part in facility design Involve PI in assessing hazard and devising control Laboratory visits Useful to monitor press releases

62 Lessons Learned Managing Use of Nanomaterials in Research Nano-enabled research tools now commercially available Users may not know potential hazards (minimal MSDS) Use of such tools may be difficult to spot Nanomaterials as consumables, i.e. more waste issues

63 Lessons Learned-- --Managing Nanosafety Establish nanomaterial database to track and document hazards and controls Assess exposure potential with information and instruments on hand Tap into faculty resources for field measurement (nanomaterial( & aerosol) Develop training, new and refresher, to disseminate nanosafety information Monitor development & update program

64 Lessons Learned Nanomaterials in Research Labs Generation of nanomaterials does not have to be hi-tech (characterization, measurement usually do) Some generation in liquid phase Gas phase generation usually sealed Samples tend to be small, some air- sensitive Nanoparticles agglomerate in air and liquid but certain procedures do increase airborne concentration

65 Challenges and Opportunities

66 Safety Management Challenges Rapid development hard to keep track Capturing nano-research information Sharing Nano-EHS info to researchers Managing ahead of regulations Managing ahead of EHS development Balancing uncertainties, practicalities, resources

67 Opportunities Obvious interest in commercial applications and ensuring product / consumer safety Ensure integration of manufacturing & research safety Example: when yield is low, increasing yield = reducing waste / fugitive Opportunity to integrate EHS development from beginning

68 Responsible Nanotechnology Many promising applications Uncertainties in potential health and environmental effects Concurrent development of technology and precautions against adverse EHS effects

69 The End Thank you