Transcript Powerpoint Presentation

Safe Work Australia’s
Nanotechnology Work Health & Safety
Program
New Reports
Howard Morris
Nanotechnology Work Health & Safety Program Manager
March 2013
Safe Work Australia’s
Nanotechnology Work Health & Safety Program
• Safe Work Australia - Australian Government agency
• Australian government funding under National
Enabling Technologies Strategy
• Focus areas
– Nanotechnologies & work health and safety regulatory framework
– Understanding hazardous properties of engineered nanomaterials
– Evaluating effectiveness of workplace controls
– Emissions and exposure measurement capability
– Information & guidance for nanotechnology organisations
– Participating in international initiatives & ensuring consistency with
international approaches
ISO TC229 Working Group 3, March
2013
Published Research Reports
www.safeworkaustralia.gov.au
Plus
• Durability of carbon nanotubes and their potential to cause inflammation
• Nanoparticles from printer emissions in workplace environments
• Health effects of laser printer emissions measured as particles
• Human health hazard assessment and classification of carbon nanotubes
ISO TC229 Working Group 3, March
2013
Measurements of particle emissions from
nanotechnology processes
Queensland University of Technology/Workplace Health & Safety Queensland
• 6 processes examined, different engineered nanomaterials
• Measurement approaches & equipment examined
•
OECD WPMN Emission Assessment guidance/NEAT
• Use of particle control values considered
•
•
Workplace exposure standards & limits
Other reference values
• Use of excursion guidance criteria
•
8hr & 15 minutes TWA, peak emissions
Report building on this research provided to OECD WPMN SG8 – currently
under review
ISO TC229 Working Group 3, March
2013
Approach for Workplace Measurement
Recommends 3-tiered assessment approach
• Tier 1 - occupational hygiene survey of process
area & measurements to identify likely points of
particle emission
• Tier 2 - measuring particle number and mass
concentration to evaluate emission sources &
workers’ breathing zone exposures
– Comparison with background levels
– Use of CPC, OPC & photometer
• Tier 3 - repeat Tier 2 measurements & simultaneous
collection of particles for off-line analysis
In practice, all 3 Tiers may not be needed
(P.McGarry et al, QUT/WHSQ, 2012)
ISO TC229 Working Group 3, March
2013
Effectiveness of LEV confirmed
Process 2 - C
7.00E+04
6.00E+04
Particle Number Concentration (p cm-3)
opened
extruder
plate
release
artificial
smoke
extrusion
machine
started polyurethane
additive only
5.00E+04
extraction
turned off
extraction turned
back on
clay
added to
hopper
extrusion
stopped
4.00E+04
local
extraction
ventilation
turned on
3.00E+04
2.00E+04
1.00E+04
13:12
12:57
12:43
12:28
12:14
12:00
11:45
11:31
11:16
11:02
0.00E+00
Time
CPC3781 background
•
CPC3781 at source
Advice on LEV use provided
(P.McGarry et al, QUT/WHSQ, 2012)
6
Health hazard assessment and classification of carbon
nanotubes (NICNAS)
• Classification criteria used
•
•
3rd Revised Edition of the GHS
Australian Approved Criteria
– being replaced by the GHS criteria but may still be used
during the regulatory transition period
• Classification for each health endpoint
•
•
•
Not classified as hazardous - data acceptable for regulatory
decision making available and do not meet criteria for
classification
Cannot be classified – No guideline studies or other suitable
scientific data acceptable for regulatory decision making, or
available data not sufficient to make classification decision.
Classified as hazardous – At least one guideline toxicity study or
other suitable data available where outcomes meet the criteria for
classification
ISO TC229 Working Group 3, March
2013
Recommended classification of carbon nanotubes
• Summary of NICNAS’ recommended GHS classifications
Classification
recommended
Health Hazard Endpoint
Classified as
hazardous
Carcinogenicity: Category 2
Specific target organ toxicity - repeated exposure: Category 2
Not classified as
hazardous
Acute toxicity: Oral, Dermal
Serious eye irritation
Skin irritation
Skin sensitisation
Specific target organ toxicity - single exposure
Cannot be
classified
Acute toxicity: Inhalation
Respiratory sensitisation
Germ cell mutagenicity
Reproductive toxicity
ISO TC229 Working Group 3, March
2013
Evaluation of potential safety (physicochemical)
hazards associated with the use of engineered
nanomaterials (Draft Report, Toxikos)
Review of published data
• Accidental explosions involving metal nanopowders
have resulted in deaths of workers
– during production of aluminium nanopowder by mechanical attrition
milling
– in premix plant of a slurry explosive factory when loading a batch
mixer with very fine aluminium flake
• Dust clouds of a number of types of engineered
nanomaterials can result in very strong explosions if
– concentrations of engineered nanomaterials in air are sufficiently
high, and
– dusts can be ignited
• Severity of explosion for engineered nanomaterials
no higher than for micron-sized counterparts
ISO TC229 Working Group 3, March
2013
Evaluation of potential safety hazards
•
Minimum explosive concentration (MEC) is significantly higher
(30-70g/m3) than found in a well-managed workplace as a result
of fugitive emissions from nanotechnology processes
•
In some situations where production is not designed and/or
controlled effectively, air concentrations in localised areas may
be sufficiently high to result in explosions
•
Minimum ignition energy (MIE) varies with material type
– Nanoscale metal powders are easily ignited (low MIE, <10mJ)
– Carbon nanomaterials are not easily ignited (high MIE, >1000mJ)
Evaluation of potential safety (physicochemical) hazards associated with
the use of engineered nanomaterials (Draft Report, Toxikos 2013)
ISO TC229 Working Group 3, March
2013
Investigating the emissions of nanomaterials from
composites and other solid articles during machining
processes (Draft Report, CSIRO)
Review of published data
• Examines:
–
–
–
–
–
how particle release was measured
workplace controls
levels of releases
types of particles emitted
potential risk to workers’ health.
• Machining processes examined:
– wet and dry cutting, drilling, grinding, sanding, abrasion
• Informed contribution to NanoRelease
ISO TC229 Working Group 3, March
2013
Emissions from solid articles during machining
• Quantity of emissions not significantly different from
machining of composites without nano-objects
• High energy machining processes
– emit significantly higher numbers of particles
– produce higher airborne mass concentrations
• Lower emissions can be achieved using wet
machining in place of dry machining
• Mixture of particles is released from composites
– Most particles emitted come from the matrix or are particles of
matrix with nano-objects embedded
– Some free engineered nano-objects are released
• 2 studies reported emission of free carbon nanotubes
& nanofibres, a number of other machining studies
did not detect the emission of free carbon nanotubes
(Draft Report, CSIRO 2013)
ISO TC229 Working Group 3, March
2013
Emissions from solid articles during machining
Potential risk to workers’ health:
• Unless reinforcing particles are of high toxicity,
similar health risk from machining of composites
with/without reinforcing nano-objects
• Potential health risk from high energy machining
processes
• Levels of emissions from low energy process should
not present a significant health risk, unless emitted
particles have high toxicity
Engineering controls can significantly reduce worker
exposure
– if designed appropriately and maintained adequately
(Draft Report, CSIRO 2013)
ISO TC229 Working Group 3, March
2013
Current Projects
Training course on nanotechnology work health
and safety (RMIT University)
Development of methodology for high throughput
nanotoxicity studies (University of South
Australia)
Update to review of toxicology & health hazards of
nanomaterials (ToxConsult)
ISO TC229 Working Group 3, March
2013
Further Information
• My contact details
Phone: +61 2 6121 9127
Email: [email protected]
• Website: www.safeworkaustralia.gov.au
ISO TC229 Working Group 3, March
2013