Nanomaterials

Nanomaterials are extremely small and have dimensions roughly between 1-100 nanometres (nm). A nanometre is 1 billionth of a metre.

• Piece of paper - 100,000 nm thick
• Human hair - 70,000 - 80,000 nm
• Red blood cell - 7,000 nm
• Virus - 10 - 100 nm

Nanomaterials are in the workplace and in the home:

• Windows – titanium dioxide coating (repels dirt)
• Batteries and computer components – silicon dioxide, zinc oxide (optimizes functionality)
• Car - carbon nanotubes in the frame (adds strength without weight)
• Cutting board - silver (controls bacteria growth)
• Makeup – silver (antibacterial and promotes penetration)
• Clothing – silver (stain resistant and antimicrobial)
• Paint – silver, silicon dioxide, titanium dioxide, carbon nanotubes (water/dirt repellant, scratch resistant, extends life)
• Cleaners – silver, silicon dioxide, fullerenes (antimicrobial)
• Sunscreen – titanium or zinc oxide (keeps it clear while keeping UV protection)
• Cement mixtures – silicon dioxide, titanium dioxide, graphene (increases flow and stiffness

Are nanomaterials hazardous? The best approach is the precautionary principle - the need to take prudent action in the face of potentially serious risk, without waiting for the completion of further scientific research.

What workplaces can do

• Implement nanomaterials management plans similar to that for substances such as asbestos and hazardous chemicals
• Screen materials before they enter the workplace
• Monitor for nanomaterials as part of workplace inspections
• Provide worker education and training
• Use elimination or substitution, where possible
• Use appropriate engineering controls, use and maintain personal protective equipment, and promote good hygiene practices

Health effects

• Can enter the body through inhalation, ingestion or absorption through the skin
• Health effects are influenced by chemical composition, shape, size, surface texture, surface charge and other factors, and their retention in tissues may be relatively short or long
• Latency period (time between exposure and manifestation of health effects) is unknown
• Have been found in the lungs, liver, kidneys, heart, reproductive organs, brain, spleen, skeleton, soft tissues and fetuses
  • Airborne nanoparticles can be deposited in the deepest part of the respiratory tract
  • Inhaled nanoparticles may enter the bloodstream and migrate to other organs
  • Some nanomaterials can cause rapid and persistent pulmonary inflammation and fibrosis, lung tumors and cardiovascular dysfunction
• Occupational exposure limits for nanomaterials could be much lower than that for related chemicals or materials

Rsources on controlling exposures

• CSA Z12885, Nanotechnologies – Exposure control program for engineered nanomaterials in occupational settings
• CAN/CSA-Z12901-2:15, Nanotechnologies – Occupational risk management applied to engineered nanomaterials - Part 2: Use of the control banding approach
• Controlling Health Hazards When Working with Nanomaterials: Questions to Ask Before You Start, NIOSH

Source: Nanotechnology and Health Network