Introduction - Nanoparticles
Nanoparticles have at least one dimension between 1 and 100 nanometers (nm)They have existed in nature since time beganExample – fine particles associated with combustion or volcanic eruptionsOnly recently (past 20 years) have they been engineered
Introduction - Examples of Engineered Nanoparticles
Carbonsexamples -Fullerenes, nanotubesOxidesexamples - Titanium dioxide, silicon dioxideMetalsexamples - Gold, zinc, nickel, copperSemiconductorsexamples - CdSe, CdS, InAs, InPPolymers/organicsexamples- liposomes
Nano-scale materials may have different properties as compared to the bulk materialFor 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 ratioExample milligrams/cubic meter of airThis type of measurement is not always acceptable when evaluating nano-scale substances with respect to hazard
Other nanoparticle characteristics, that can’t be easily measured in the workplace, may be more important in hazard assessment for, such asSurface areaNumber of particlesElectrical charge of the particleAgglomeration of particlesParticle sizeSolubility
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
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 substanceTherefore, professional judgment must be used when conducting hazard evaluations with nano-scale particles.
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 sandwichedbetween transparent adhesive plastictape.This should make exposure essentially zeroHowever, disposable gloves are recommended as a general precaution.
Hazard Assessment - Ingestion
Ingestion is highly unlikely for the nano-scale alloy particles used at UTSISteps to prevent ingestion include:Use gloves while handling the materialsRemove gloves and wash hands following work in the labDon’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 presentIn 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 handlingHowever, it’s prudent to limit unnecessary inhalation
Hazard Assessment – Accidental Release
In the event an accidental release of the nanoparticles occurs:Avoid breathing the dustUse gloves to clean up the spilled materialUse wet methods (damp paper towel or other material) to collect the spillAvoid creating a dust
Hazard Assessment –Accidental Release
Clean up materials, including personal protective equipment, from a spill may be discarded via regular trashThey aren’t considered a hazardous waste.It’s suggested they be placed in a sealed plastic bag and kept damp if possible
Labeling – Containers of the nano-particles must be labeledThe 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
Employees who are likely to come in contact with the material should receive trainingThe 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.
Material Safety Data Sheet should be made available to the workersEmployee’s should know the location of UTSI’s Hazard Communication Plan (also called HazCom or Right to Know Plan)
Individuals who are likely to come in contact with the material should know:How to detectthe presence or release of athe nanoparticles(such asvisualappearance)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)
The chemical, physical and toxicological properties of europium have not been thoroughly investigated and recorded.
Unable to find an MSDS for Europium Sulfide on the InternetHowever, 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
Europiummetalsare moderately to highly toxic.Symptomsof toxicityincludewrithing, ataxia, labored respiration, walking on the toes with arched back and sedation.Lowtoxicity by ingestion exposure.Again, exposure is extremely unlikely in the UTSI lab and none of these symptoms are anticipated.
Intraperitoneal route is highly toxicSubcutaneous 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 is fairly innocuous and shouldn’t present a distinct health hazard. The primary hazard would be irritation of skin or mucous membranes upon contactA copy of the MSDS can be found at:http://fscimage.fishersci.com/msds/09765.htm
The primary health effect of an iron-cobalt alloy is irritation of the skin or mucous membranes upon contactA material safety data sheet for iron-cobalt alloy can be found at:http://www.alloycastproducts.com/docs/MSDS.pdf
Cobalt can be hazardous by ingestion or inhalation.An MSDS for cobalt can be found at:http://www.sciencelab.com/msds.php?msdsId=9923518It’s unlike that exposure will occur in the UTSI lab.
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 labsNanoparticles in a liquid are less hazardous as compared to dry powder forms.