NANOPARTICLES: A PRIMER FOR GENERAL PRACTITIONERS Updated in 2016 by: www.skcinc.com

JUST WHEN YOU THOUGHT YOU KNEW EVERYTHING ABOUT PARTICULATES… WAIT THERE’S MORE. A totally new type of particle in a new state of matter….NANOPARTICLE.

NANOPARTICLES: A NEW STATE OF MATTER Even though they are a particle, they behave like a vapor. Mode of deposition in the body is not like a dust particle or fiber that deposits in the respiratory system. They diffuse like a gas/vapor. Nano-sized particles cannot be regarded as a liquid or solid. NANOPHASE

NANOPARTICLES DEFINED Nano-sized particles have at least one dimension between 1 and 100 nanometers (0.001-0.1 microns). Found in a variety of shapes including quantum dots, nanofibers, nanotubes, and nanobelts.

NANOPARTICLES: AN INDUSTRIAL REVOLUTION Many industry sectors are using nano-enabled materials in paints, coatings, electronics, solar panels, medical devices and drugs, consumer products, and more.

NANOPARTICLES: HEALTH CONCERNS GREATER BIOREACTIVITY due to larger surface area GREATER MOBILITY IN THE BODY due to smaller size The potential RELEASE of nano-particles from nano-enabled products is a subject of active research. CONSIDER: Silver nanoparticles are used in toys for the anti-bacterial properties.

HEADLINE: OCTOBER 2014 AIHA SYNERGIST ARTICLE Unknown Risks: Nanomaterials in Construction Engineered nanomaterials may have a much longer life cycle, but will change over their expected life. Safety Data Sheets/Hazard Communication should inform workers whether nanoparticles have been added to the products they may install, disturb, or demolish at construction sites. (similar to asbestos) ISO produced guidance in 2012 on preparing SDS’s for nanomaterials.

NANOPARTICLES vs. ULTRAFINES Incidental nanoparticles in air produced unintentionally by combustion engines, welding, etc. Have properties similar to the engineered nanoparticles. Nanoparticles Particles intentionally engineered for specific applications and products.

NIOSH UPATE ON SAMPLING OF NANOMATERIALS In March 2016, NIOSH published a refinement to their 2009 publication of the NANOMATERIAL EXPOSURE ASSESSMENT TECHNIQUE (NEAT).

Why is this important TO ALL HEALTH & SAFETY PROFESSIONALS? Engineered nanomaterials (ENMs) are being used in many products across all industry sectors. NIOSH noted that “increasingly, workers are involved not only in production of the ENMs, but in use, recycling, and disposal of ENMs or products containing ENMs.” There is intense study to ensure that fibrous nanomaterials don’t become the next asbestos. This is a particular concern for workers involved in demolitions of buildings containing ENMs.

Why is this important TO ALL HEALTH & SAFETY PROFESSIONALS? Nano-sized particles are present in many workplaces. A recent journal article reports desktop 3D printers are “high emitters” of ultra-fine i.e. nano-sized particles (Atmospheric Environment, 79, 2013). Further, ink or base materials for larger scale 3D printers are frequently metal and polymer systems based on engineered nanomaterials.

A quick overview WHAT’S CHANGED IN NIOSH NEAT 2.0 NIOSH NEAT 1.0 was focused on EMISSIONS that could lead to workplace exposures. Therefore, the original approach was to identify processes or job tasks where the release of nanomaterials could possibly occur. NIOSH NEAT 2.0 focuses on quantitative measurements of occupational exposures using personal breathing zone and area filter samples. Particle counters are also used to evaluate peak emissions.

Exposure assessment strategy in the original niosh neat 1.0 When particle counts were significantly above background, short-term filter samples were taken typically for the duration of the work task. Higher flowrates of 7 L/min were used to enhance detection using open-face 37-mm filter cassettes. particle counters were used first to: Determine levels of nanoparticles emitted during various work processes and tasks. Determine background levels for comparison.

Problems encountered with the neat 1.0 approach PARTICLE COUNTERS were not used in data-logging mode which made it difficult to capture meaningful data over the entire shift. Short-term measurements did not capture transient changes in particle count from incidental sources or from worker tasks. HIGH FLOWRATE of 7 L/min created issues with pressure drop for sampling pumps and raised concerns over sampling outside the parameters specified in validated methods.

Exposure assessment strategy in niosh neat 2.0 Instead of starting with particle counters and then doing just task-based filter sampling, NIOSH NEAT 2.0 utilizes a more standard hygiene approach of: Task-based and full-shift area and personal filter samples COMBINED WITH Particle counters in data-logging mode to supplement the data

Of particular note IN NIOSH NEAT 2.0 -FULL-SHIFT SAMPLING is done not only for the personal breathing zone samples on workers. -FULL-SHIFT BACKGROUND DATA is also collected to better understand fluctuations of nanos in ambient air and in the general work area that are not related to the specific ENM work activity under review. SKC NOTE: Sounds similar to the approach for a mold investigation.

Filter-based samples: the specifics TWO SIMULTANEOUS OPEN-FACE 25-MM FILTER samples are collected for both area or on-worker assessments. One is for analysis elemental mass and the other is for microscopic determination of particle size, shape, identification. To reach the LOQ for short-term task monitorinG, NIOSH recommends higher flows typically up to 5 L/min. Filter and cassette type will depend on the target compound and analysis technique following standard NIOSH methods.

Filter-based samples: the specifics A THIRD FILTER SAMPLE is often collected with a size-selective particulate sampler such as the IOM for the inhalable fraction or a cyclone for the respirable fraction. Since nanos tend to agglomerate, the IOM will prove useful in collecting larger particles. Respirable dust samplers will allow for the separation and collection of the smaller particles for comparison to exposure limits.

NIOSH RECOMMENDED EXPOSURE LIMITS (RELs) AND SAMPLING METHODS FOR NANO-SIZED MATERIALS REL of 300 ug/m3 for nanosized titanium dioxide A respirable dust sampler is used with a 25-mm PVC filter for gravimetric analysis by NIOSH Method 0600. If levels warrant, a 25-mm MCE filter is used for elemental analysis by NIOSH Method 7300. REL of 1 ug/m3 for carbon nanotubes and nanofibers A respirable dust sampler is used with a 25-mm quartz filter for analysis of elemental carbon by NIOSH Method 5040. A second sample using an open-face 25-mm MCE filter is used for electron microscopy.

FILTER SAMPLING: TECHNICAL NOTE Concern has been raised that nanoparticles will go through the pores of typical filters used for microscopic/chemical analysis. NIOSH says this will NOT happen. The activity of nanoparticles is so intense that the particles constantly collide and DO NOT go through the pores like a sieve.

PARTICLE COUNTERS USED TO MEASURE NANOPARTICLES Condensation Particle Counters (CPC) Particles are passed through an alcohol bath at an elevated temperature, cooled in a condenser block, and detected by a light-scattering device. The CPC technology allows for the measurement of particles down to 10 to15 nm. But, you only get one particle count with this instrument 1.0 um is the largest particle size detected.

PARTICLE COUNTERS USED TO MEASURE NANOPARTICLES Optical Particle Counters (OPC) The principle of laser light scattering is used to simultaneously measure particles in various size ranges. The OPC technology allows for the measurement of total number of particles per liter of air within 3 to 6 defined size ranges. It can only detect particle sizes down to 300 nm, but can detect larger particles (agglomerates) up to 5 um.

CONDENSATION PARTICLE COUNTERS Detects particles as small as 15 nm and as large as 1um Concentration range up to 100,000 particles/cm3 Datalogging Data management software SKC 745-3800

OPTICAL PARTICLE COUNTERS 3-channel Model: Economical option Size ranges: 0.3, 0.5, and 5.0 m User-selectable sampling time and frequency Internal datalogger Includes data management software SKC 745-3887

OPTICAL PARTICLE COUNTERS 5-channel Model: Flexible option Size ranges: 0.3, 0.5, 1.0, 3.0, and 5.0 m Optional probe for RH/temp and air velocity Internal datalogger Includes data management software SKC 745-3886

SIOUTAS IMPACTOR The Sioutas Personal Cascade Impactor is also being used to evaluate concentration and size distribution of nanoparticle exposures. The Sioutas impactor will collect particles from <250 nm to >2500 nm into 5 size fractions. SKC 225-370

WIPE SAMPLES FOR NANOMATERIALS Standard wipes such as Ghost Wipes™ can be used to analyze metal compounds on common surfaces touched by workers including doorknobs, computer keyboards, and telephones. Wipe samples can also be collected on ledges or shelves to evaluate ventilation or other engineering controls. Wipe samples followed by elemental analysis can provide valuable information on the potential for dermal exposure to the nanomaterial.

See the NIOSH Nanotechnology Topic Page at FOR MORE INFORMATION See the NIOSH Nanotechnology Topic Page at www.cdc.gov/niosh/topics/nanotech