Engineered Nanoparticle Exposures in Construction: Presentation to the ACCSH

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CPWR - The Center for Construction Research and Training

Summary Statement

This PowerPoint was presented to the OSHA Advisory Committee for Construction Safety and Health on November 27, 2012 by Dr. Bruce Lippy, Director of Safety Research for CPWR. The presentation was given in conjunction with one by Dr. Kristen Kulinowski of the Science and Technology Policy Institute to provide the committee with a background on the potential risks posed to construction workers by applications containing nanoparticles.
November 2012

I would like to address four questions:

  1. What nanomaterials are found in construction?
  2. What do we know about exposure to nanoparticles in construction?
  3. How are the hazards being communicated to workers?
  4. What is CPWR planning to do about nanomaterials as the NIOSH-funded National Construction Center?

Question One

What nanomaterials are found in construction?

Illustration of nanomaterial

A recent study found carbon nanotubes in the airborne particles at Ground Zero

Debris at Ground Zero

This presentation is focused on engineered nanoparticles

There are many promising applications in construction, but limited commercialization at this point

Table of benefits from Engineered Nanoparticles, by type of construction material

Lee, Mahendra & Alvarez (2010)

“Cost and the relatively small number of practical applications, for now, hold back much of the prospects for nanotechnology.” -Nanoforum Report: Nanotechnology and Construction, November 2006

There is more activity in Europe, mostly in coatings, cement and concrete

  • 94 available products identified
  • reduced weight of concrete with silica fume*
  • increased strength and elasticity of concrete
  • improved weathering of exterior surfaces
  • biocidal surfaces for walls of surgery rooms

*Aggregate of amorphous SiO2 nanoparticles

Broekhuizen et al. 2011

These tiles contain nano-titanium dioxide

Image of BoralPure Tiles, which contain nano-titanium dioxide

We would like to test exposures

One roof can oxidize NO2 from 10,800 miles of driving, according to the manufacturer

Illustration of roof tiles oxidizing NO2

Emaco NanoCrete patching compounds does not contain nanoparticles.

From the manufacturer: “Nanotechnology does NOT mean nano-sized particles: We do not use any nano-particles in our cement formulations.”

These hydrated silicates are nano-structured; they have nano-sized holes

Nano-structured hydrated silicates

NIOSH has begun an HHE looking at Aspen Aerogel insulation, another nanostructured product

Mark Methner of NIOSH

Mark Methner, NIOSH

Question Two

What do we know about exposure to engineered nanoparticles in construction?

Not much!

We know construction workers may be at risk

“Inhalation of manufactured nanomaterials during coating, molding, compounding, and incorporation can pose a respiratory health risk to workers.” - Lee, J., Mahendra, S. & Alvarez P.J. (2010, July).

We do have corroborating data on ultrafine exposures showing respiratory issues

Photograph of trade school apprentice at risk of ultrafine exposures

Apprentice from UA Mechanical Trades School in Landover, MD, 9/12 
Photo courtesy eLCOSH

Sampling was conducted onsite for several real processes in 2009
(Broekhuizen et al, 2011)

  • Mixing Nanocrete mortar
  • Applying spray-on TiO2 coating onto glass

Particle sampling during mixing of 6 bags of Nanocrete mortar (Broekhuizen et al, 2011)

Graph of particle sampling during mixing of six bags of Nanocrete mortar, measured over time in seconds

"Workplace measurements suggest a modest exposure of construction workers to nanoparticles (NPs) associated with the use of nanoproducts."

NIOSH chose mass-based REL over counting with electron microscopy

Front Cover of the NIOSH Current Intelligence Bulletin: Occupational Exposure to Carbon Nanotubes and Nanofibers

  • NIOSH Method 5040
  • Counting protocols haven’t been developed, although ASTM committee is close

REL of 7 µg/m3

elemental carbon (EC) as an 8-hr TWA

37-mm quartz-fiber filter

37 millimeter quartz-fiber filter

Nanoparticles Have Almost No Mass

Illustration of the size of a 10 micron particle in relation to the size of 10 nanometer particles

Courtesy Larry Gibbs

Large particles bias mass measurements

If you’re carrying a grocery bag full of cantaloupes, you’re not going to notice a handful of grapes.
Courtesy L. Gibbs

Transmission electron microscopy is the gold standard and will be used in CPWR’s work

Transmission electron microscopy in action

TEM allows several measurements

Graph of Transmission electron microscopy measurements

  • Shape
  • Chemical composition
  • Particle count
  • Particle length and diameter

Image of MWCNT, courtesy of NIOSH

NIOSH image of MWCNT

You do the analysis:

Do these particles appear similar?

"No" box is checked, indicating that these particles do not appear similar

Image of Bulk product sample particle

Bulk product sample

Image of Air sample particle

Air sample

Question Three

How are the hazards being communicated to workers?

Construction worker using a level and wearing safety goggles

Photo courtesy eLCOSH

"80% of the workers’ reps and 71% of the employers’ representatives were not aware of the availability of nanomaterials and were ignorant as to whether they actually use nanomaterials at their workplace."

- 2009 Survey response from 28 construction workers and employers in Europe (N = 144) Broekhuizen et al. 2011

We haven’t been doing a great job communicating the hazards of standard industrial chemicals

- Hazard Communication: A Review of the Science Underpinning the Art of Communication for Health and Safety Sattler, Lippy & Jordan, May, 1997

Sattler, Lippy & Jordan 1997 review of hazcom literature for OSHA was the only one for a decade

  • University of Maryland contract with OSHA. Report at:
  • Accuracy of technical information was a problem
  • Most studies were based on reported preferences, not behaviors
  • Populations studied were students not workers

Comprehensibility of MSDSs was not good

Literate workers only understood 60% of the health and safety information on sample MSDSs in three different comprehensibility studies:

  • Printing Industries of America, 1990
  • Kolp, Sattler, Blayney, Sherwood, 1993. Am. J. Ind. Med
  • Phillips, 1998

Findings from a newer review of the literature did not show improvements

Chart showing the lack in improvements that were gained from safety literature

Nicol et al. 2008, Am. J. Ind Medicine

Lippy Group reviewed NIOSH collection of nano MSDSs

  • N = 49 MSDSs
  • Reviewed all of the MSDSs
  • 33% did NOT identify the nano component
  • 52% did NOT have any cautionary language

Large surface area in relation to particle size enhance physical and chemical properties (nanosilver)

Most (62%) just referenced PELs and TLVs for the macro size

  • 32% percent indicated nothing
  • Only 6% used cautionary language about using PELs/TLVs

MSDS for Carbon Nanotube

Chart identifying the nuisance dust standard for Carbon Fullerene

The GHS changes will be a big improvement, but OSHA can do more using the existing SDS format

  • ANSI Section 16 “Other Information” is the key.
  • Useful risk information about nanoparticles can be included in Section 16.
  • OSHA could create an eTool helping SDS developers with the appropriate language

Question Four

What is CPWR planning to do about nanomaterials as the NIOSH-funded National Construction Center?


Two CPWR Initiatives

1. Identify specific construction-related products and create an inventory

Nano-phase silica-filled epoxy adhesive SEM

Nano-phase silica-filled epoxy adhesive SEM image (scale bar = 100 nm)

Wilson Center has 1317 products, produced by 587 companies located in 30 countries (03-10-11)

Some of the Wilson Center's Products

The Europeans have created an inventory of construction products

  • FIEC represents construction employer organizations in 29 countries
  • EFBWW represents 75 affiliated construction unions in 31 countries and represents a total of 2,350,000 members

Broekhuizen et all. 2011

Newly revised site for nano!

Screen shot of the newly revised eLCOSH Nano site

Second CPWR Initiative

1. Identify specific construction-related products and create a registry

2. Identify applicable control technologies currently in the CPWR Construction Solutions database and measure their effectiveness with nanoparticles

Will these control nanoparticles in construction?

Image of Airtec Jet-Rotary Hand-Held Conrete Milling Machine

Airtec Jet-Rotary Hand-Held Concrete Milling Machines

Image of Pentek Air-Powered COMPACT-VAC High Performance HEPA Vacuum

Pentek Air-Powered COMPACT-VAC High Performance HEPA Vacuum

Conventional controls should work with nano

Illustration of exhaust ventilation depending on particle size

Courtesy NIOSH

CPWR will be working with a firm called EPI Services that has a test chamber

EPI Service's Test Chamber

Controlled area where construction products will be tested.
Photo courtesy EPI Services, Inc.

Along with its own website and distribution system, CPWR will work with other organizations including yours

Screen shot of


for more info contact:
Bruce Lippy, Ph.D., CIH, CSP
Director of Safety Research
410-916-0359 cell