Nanotechnology describes a wide range of technologies and materials that create, manipulate, or use particles of the same minute size. The materials used, known as nanoparticles, have dimensions roughly between 1 and 100 nanometers (nm), each nanometer being only 1 billionth of a meter.
It is difficult to determine the health and safety concerns associated with the use of nanotechnology because each type of nanomaterial is different. Since they are characterized by their size rather than their material composition, different sets of nanoparticles will have unique effects.
Additionally, research on the potential applications of nanotechnology is rapidly expanding worldwide and, according to the National Institute for Occupational Health and Safety (NIOSH), new consumer products using nanotechnology are emerging at a rate of three to four per week. Furthermore, NIOSH estimates that within the next decade, two million workers will be employed in the nanotechnology industry, making health and safety research even more crucial than it was before.
What Are Nanoparticles?
Nanoparticles occur naturally, but can also be man-made. Man-made sources of nanoparticles include combustion by-products from, for example, welding, cooking, and diesel exhaust. Naturally occurring nanoparticles can be found in viruses and volcanic ash, as well as be produced by algae and plants.
How Is Nanotechnology Used?
Nanotechnology is now a feature of many industries. Some common commercially available uses include:
- Computer hard drives which use the magnetic properties of nanoparticles to store data
- Water filtration systems
- Medical applications, such as dental bonding agents, as well as for dressing burns and wounds
- Protective and glare-reducing coatings for eyeglasses and cars
- Cosmetics and sunscreens (find out more about UV Risk in the Workplace)
- Sports equipment, such as longer-lasting tennis balls
Risk to Workers: Health Concerns
Nanomaterials pose an occupational health hazard due to their potential to enter the body. Since most nanomaterials are airborne nanoparticles, the most common route of entry into the body is through the respiratory system. Additionally, nanoparticles may also be ingested or come into direct contact with the skin. The main health concerns associated with nanomaterials, then, are that they can be easily inhaled and deposited in the respiratory tract and can enter the blood stream and translocate to other organs.
Furthermore, research have shown that:
- Nanoparticles can cause pulmonary inflammation and lung tumors
- The chemical composition, crystal structure, and size of nanoparticles can influence their oxidant generation properties, becoming toxic to cells
- Workers exposed to airborne nanomaterials reported adverse lung effects including obstructive lung diseases (e.g., asthma, bronchitis, and chronic obstructive pulmonary disease [COPD]), fibrotic lung disease, as well as lung function decrements (learn more about Work-related Asthma)
Risk to Workers: Safety Concerns
At present, not much research has been done regarding the physical and chemical characteristics of nanoparticles. So, we have insufficient information to allow us to get a clear picture of the safety concerns. However, when compared to materials with similar mass concentrations, as well as the unique chemical compositions of nanomaterials, it can be assumed that nanoparticles can be highly combustible, posing a serious fire and explosion risk.
Factors Affecting Workers’ Exposure to Nanomaterials
In addition to the amount of material being used, the degree of containment and the duration of exposure, there are several other factors that influence workers’ exposure to nanomaterials. According to the Centers for Disease Control and Prevention (CDC), some workplace factors that can increase the potential for exposure include:
- Working with nanomaterials in liquid media without adequate protection (e.g. gloves)
- Generating nanomaterials in the gas phase in non-enclosed systems
- Cleaning up waste materials or dust collection systems used to capture nano-aerosols
- Handling powders of nanostructured materials
- Maintaining equipment and processes used to produce nanomaterials
Due to the limited amount of information available regarding the health and safety concerns associated with the exposure to nanomaterials, it is crucial that both employers and employees take measures to minimize potential risks. Some precautionary measures may include:
1. Engineering control techniques
Engineering control techniques can be used to control airborne exposure to nano-aerosols, such as:
- Isolating the generation source from the employee or source enclosure
- Using local exhaust ventilation systems to capture airborne nanoparticles, for example, one with a high-efficiency particulate air (HEPA) filter
2. Administrative control techniques
This may involve the implementation of a risk management program to help minimize the potential for exposure to nanoparticles. A successful program should:
- Evaluate the hazard posed by nanomaterials—this can be done by reviewing information that exists on the physical, chemical, and toxicology data of the materials
- Assess the employee’s job task to determine the level of exposure to nanomaterials, as well as frequency and duration
- Education and training for employees regarding the best practices for working safety with nanomaterials, for example: (i) properly handling nano materials; (ii) cleaning up work areas using a HEPA vacuum; (iii) avoiding eating or drinking in work areas where nanomaterials are being handled; and (iv) washing hands in hand-washing facilities provided
- Establish procedures for installing, monitoring, and evaluating engineering controls
- Establish procedures for providing employees with the appropriate personal protective equipment (PPE)
3. Personal protective equipment
Although there are currently no guidelines regarding the selection of PPE for the prevention of exposure to nanoparticles, it is recommended that employers provide their employees with gloves and coveralls to protect them from dermal exposure to nano-aerosols.
Additionally, respirators may be provided based on toxicity information, frequency and duration of employee’s exposure, as well as exposure measurement data. Furthermore, employers should mandate that when selecting their respirators that employees do a fit test to ensure the efficient and effective use of the respirator.
Nanotechnology and Workplace Health and Safety
Due to the broad range of possible nanotechnology applications, combined with the fact that there are currently no national or international standards on workplace exposure limits to nanoparticles, there is an important need for the continued evaluation of the potential health risks associated with the exposure to nanomaterials. These evaluations can be conducted via occupational health surveillance, which is an integral part of occupational health and safety programs and manage the risks associated with working with nanotechnology.