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Nanoparticle Safety. UTSI November 2011. Introduction - Nanoparticles. Nanoparticles have at least one dimension between 1 and 100 nanometers (nm) They have existed in nature since time began Example – fine particles associated with combustion or volcanic eruptions
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Nanoparticle Safety UTSI November 2011
Introduction - Nanoparticles • Nanoparticles have at least one dimension between 1 and 100 nanometers (nm) • They have existed in nature since time began Example – fine particles associated with combustion or volcanic eruptions • Only recently (past 20 years) have they been engineered
Introduction - Examples of Engineered Nanoparticles • Carbons examples - Fullerenes, nanotubes • Oxides examples - Titanium dioxide, silicon dioxide • Metals examples - Gold, zinc, nickel, copper • Semiconductors examples - CdSe, CdS, InAs, InP • Polymers/organics examples- liposomes
Introduction -Nanoparticles • Nano-scale materials may have different properties as compared to the bulk material • For example gold is malleable in the bulk form but is brittle and appears red in color at the nano-scale
Introduction – Monitoring Measurement of most hazardous air contaminants is done on a mass-to-volume ratio Example milligrams/cubic meter of air This type of measurement is not always acceptable when evaluating nano-scale substances with respect to hazard
Introduction-Monitoring • Other nanoparticle characteristics, that can’t be easily measured in the workplace, may be more important in hazard assessment for, such as • Surface area • Number of particles • Electrical charge of the particle • Agglomeration of particles • Particle size • Solubility
Introduction • Nano-scale particles haven’t been fully evaluated with respect to toxicity, especially for chronic exposures. • Therefore, it’s necessary to have an increased level of safety to offset uncertainties with respect to risk
Controls • Traditional controls such as ventilation, respirators, gloves, etc. work well against nanoparticles according to the National Institute for Occupational Safety and Health (NIOSH). • Disposable nitrile gloves are recommended for use with nanoparticles in the UTSI lab
Material Safety Data Sheets • Materials Safety Data Sheets (MSDS) are available for various materials. • However, the MSDS don’t address nano-scale particles of the substance • Therefore, professional judgment must be used when conducting hazard evaluations with nano-scale particles.
Hazard Assessment • Most nano-scale dusts can act as a mechanical irritant to the skin, and mucous membranes (eyes, nose and throat). • Nanoparticles in a liquid are not capable of becoming airborne and therefore present less of a hazard
Hazard Assessment - Dermal • The nanoparticles used at UTSI are sandwiched between transparent adhesive plastic tape. • This should make exposure essentially zero • However, disposable gloves are recommended as a general precaution.
Hazard Assessment - Ingestion • Ingestion is highly unlikely for the nano-scale alloy particles used at UTSI • Steps to prevent ingestion include: • Use gloves while handling the materials • Remove gloves and wash hands following work in the lab • Don’t allow hand-to-mouth contact (e.g. eating, drinking) while working in the lab.
Hazard Assessment - Inhalation • Inhalation can be the most significant route of entry into the body for an airborne material. • Particles less than 5 microns (5000 nm) in size can penetrate deeply into the lungs where some clearance mechanism (cilia) are not present • In addition, smaller particles are likely to stay airborne for a longer period of time
Hazard Assessment - Inhalation • It’s unlike that any of the nano-scale alloys used at UTSI would be inhaled through routine handling • However, it’s prudent to limit unnecessary inhalation
Hazard Assessment – Accidental Release • In the event an accidental release of the nanoparticles occurs: • Avoid breathing the dust • Use gloves to clean up the spilled material • Use wet methods (damp paper towel or other material) to collect the spill • Avoid creating a dust
Hazard Assessment –Accidental Release • Clean up materials, including personal protective equipment, from a spill may be discarded via regular trash • They aren’t considered a hazardous waste. • It’s suggested they be placed in a sealed plastic bag and kept damp if possible
OSHA Compliance • Labeling – Containers of the nano-particles must be labeled • The OSHA HazCom labeled should contain: • Name of the substance (example: iron oxide) • A hazard warning (example: caution, dust may be irritating) • Name of the responsible individual (or company) who is familiar with the substance
OSHA Compliance • Employees who are likely to come in contact with the material should receive training • The information in this PowerPoint presentation should meet the requirements for training. • Results of training must be documented, which can be done by a quiz, sign-in sheet or by other means.
OSHA Compliance • Material Safety Data Sheet should be made available to the workers • Employee’s should know the location of UTSI’s Hazard Communication Plan (also called HazCom or Right to Know Plan)
OSHA Compliance • Individuals who are likely to come in contact with the material should know: • How to detect the presence or release of a the nanoparticles (such as visual appearance) • Methods of self –protection (such as gloves or the use of wet methods for clean up and not eating food or drinking in the lab)
Europium Sulfide • The chemical, physical and toxicological properties of europium have not been thoroughly investigated and recorded.
Europium Sulfide • Unable to find an MSDS for Europium Sulfide on the Internet • However, it should behave similar to Europium chloride. • Information the next two pages regarding europium were taken from: http://www.espirareearth.com/MSDS/Europium%20Chloride.htm
Europium Sulfide • Europium metals are moderately to highly toxic. • Symptoms of toxicity include writhing, ataxia, labored respiration, walking on the toes with arched back and sedation. • Low toxicity by ingestion exposure. • Again, exposure is extremely unlikely in the UTSI lab and none of these symptoms are anticipated.
Europium • Intraperitoneal route is highly toxic • Subcutaneous route is poisonous to moderately toxic. • The production of lung and skin granulomas after exposure to them requires extensive protection to prevent such exposure
Iron Oxide • Iron oxide is fairly innocuous and shouldn’t present a distinct health hazard. The primary hazard would be irritation of skin or mucous membranes upon contact • A copy of the MSDS can be found at: http://fscimage.fishersci.com/msds/09765.htm
Iron-Cobalt Alloy • The primary health effect of an iron-cobalt alloy is irritation of the skin or mucous membranes upon contact • A material safety data sheet for iron-cobalt alloy can be found at: http://www.alloycastproducts.com/docs/MSDS.pdf
Cobalt Alloys • Cobalt can be hazardous by ingestion or inhalation. • An MSDS for cobalt can be found at: http://www.sciencelab.com/msds.php?msdsId=9923518 • It’s unlike that exposure will occur in the UTSI lab.
Summary • The hazards associated with nano-particles have not been fully characterized. • General good lab practice, including the use of gloves, will be enough to control exposure in the UTSI labs • Nanoparticles in a liquid are less hazardous as compared to dry powder forms.