Health and Safety ReportVolume 6, Issue 10 - October 2008

Preliminary study says carbon nanotubes look and act like asbestos fibres

Imagine tiny wiry tubes that are about 50,000 times thinner than a single strand of hair, and stronger than steel. These tiny tubes made of rolled up sheets of carbon hexagons are better known as carbon nanotubes. They look and act much like asbestos, according to a recent preliminary study, raising concerns with researchers.

Nanotechnology involves working at the nanometre scale of small numbers of atoms to produce materials and devices. It's at the forefront of research and technology development - and carbon nanotubes are the building blocks. Most carbon nanotubes are made from sheets of graphite about a nanometre, or one billionth of a metre wide, and formed into cylinders. Nanotubes are important in electrical research and the next-generation of computer chips and are also being developed for use in new drugs, batteries and other products. However some scientists and environmentalists are concerned that they could pose hidden dangers.

A recent study showed that inhaling carbon nanotubes in sufficient quantities could be as harmful as breathing in asbestos. During the study, led by the Queen's Medical Research Institute at the University of Edinburgh/MRC Center for Inflammation Research in Scotland, scientists observed that the long, needle-like fibre shape of carbon nanotubes look and behave like asbestos fibres. The researchers reached their conclusions after they introduced the needle-thin nanotubes into the abdominal cavities of lab mice and found that the inside lining of the animals' body cavities became inflamed and formed lesions.

This resemblance raises the concern that the nanotubes may cause illness similar to that linked to asbestos. Asbestos can cause mesothelioma, a deadly cancer of the membrane lining the body's internal organs (especially the lungs) that can appear 30 to 40 years after exposure. Most people who develop mesothelioma have worked on jobs where they inhaled asbestos particles.

Study co-author Ken Donaldson stated, "We still don't know whether carbon nanotubes will become airborne and be inhaled, or whether, if they do reach the lungs, they can work their way to the sensitive outer lining. But if they do get there in sufficient quantity, there is a chance that some people will develop cancer-perhaps decades after breathing the stuff."

Donaldson also commented on what he deemed to be the upside of the findings. "Short or curly carbon nanotubes did not behave like asbestos, and by knowing the possible dangers of long, thin carbon nanotubes, we can work to control them. It's a good news story, not a bad one. It shows that carbon nanotubes and their products could be made to be safe."

But Donaldson added that the present study only tested for fibre-like behaviour and did not discount the potential for carbon nanotubes to damage the lungs in other ways. "More research is still needed if we are to understand how to use these materials as safely as possible," he notes.

It is estimated that the market for carbon nanotubes will continue to grow and could easily reach 1-2 billion dollars annually within the next seven years, according to studies.

Disasters don't always start with chemicals. Even something as sweet as sugar can explode, as the people of Port Wentworth, GA found out when a sugar dust explosion at the Sugar Dixie Crystals plant killed 13 people and left others critically injured with severe burns.

The Oregon branch of the U.S. Occupational Safety and Health Administration (OSHA) has issued an alert to warn industries of the dangers of combustible dust. Injuries and fatalities have occurred in the state of Oregon because of a wood-dust fireball, dust flash from powder-coating filters, and a grain-dust explosion.

Assessing the risk

The Industrial Fire Hazards Handbook from the National Fire Protection Association states that "any industrial process that reduces a combustible material and some normally noncombustible materials to a finely divided state presents a potential for a serious fire or explosion." Industries that are potentially at risk include those that manufacture or handle food (such as candy, starch, flour or feed), plastics, wood, rubber, furniture, textiles, pesticides, pharmaceuticals, dyes, coal, metals (such as aluminum, chromium, iron, magnesium, and zinc), and industrial plants that generate fossil-fuel power.

Any "material that will burn in air" in a solid form can be explosive when in a finely divided form. It is possible for different dusts of the same chemical material to have different ignition and explosive characteristics. These depend on particle size, shape, moisture content, and other variables. If you are not sure whether or not a product produces combustible dust, one possible source of information is the Material Safety Data Sheet (MSDS) for the product, however OSHA recommends checking with the chemical manufacturer for additional information.

For a dust fire to occur, three elements must be present: combustion dust (fuel), an ignition source (heat), and oxygen in the air (oxidizer). When two other elements are added to the mix - dispersion of dust particles in sufficient quantity and concentration, and confinement of the dust cloud - an explosion will occur.

OSHA recommends that facilities assess their potential for dust explosions by looking at the following:

• Materials that can be combustible when finely divided;


• Processes that use, consume or produce combustible dusts;


• Open areas where combustible dusts may build up;


• Means by which dust may be dispersed in the air; and


• Potential ignition sources.

Employees must be trained in safe work practices specific to dust control and ignition source control, which apply to their job tasks and to the entire plant. Canadian employers should review their relevant legislation and ensure the workplace is in compliance.

You use your hands constantly. They're handy for all sorts of tasks, including unwanted ones, such as picking up germs and spreading them around. Thankfully, it's very easy to wash your hands, but there is a right way to do it. Hurrying out of the bathroom stall, rinsing your fingertips quickly under the tap and wiping them on your pants as you rush out the door does not work.

Proper hand washing is the most effective way to prevent the spread of infections and avoid getting sick. The goal is to stop the spread of "germs," which is a general term for microbes such as viruses and bacteria. Germs spread when you touch another person, or when you touch a contaminated object and then touch your own face. Hand-to-hand contact is often responsible for the spread of the common cold, flu, and gastrointestinal disorders.

So take a moment to learn this technique:

How to wash your hands

Remove rings or other jewellery. Use plenty of warm water and soap to form a lather. Rub the hands, wrists and forearms to create friction, making sure to get under the nails and between the fingers. Do this for at least 20 seconds. If you don't feel like counting, sing "Happy Birthday To You" in your head - twice. Then rinse your hands under running water and dry your hands with a single use towel or air dryer. Turn off the tap with a paper towel or tissue - then throw it in the garbage. Be careful not to touch dirty surfaces (taps, door handles etc) with your bare hands as you leave the bathroom.

Soap does not generally kill microorganisms, but it creates a slippery surface that allows these contaminants to "slide off" the skin. Experts agree, however, that antibacterial soaps are generally "overkill" except in hospitals and should be used with caution.

When you don't have access to soap and water, waterless hand scrubs (lotions or towelettes made with ethyl alcohol and skin softeners) can be an effective alternative. Hands that are heavily contaminated with dirt, blood, or other organic materials, however, should be scrubbed in soap and warm water.

When to wash up

You cannot see germs, but it is wise to wash your hands in these situations:

• When hands are visibly soiled.


• After contact with body fluids - using the washroom, changing a diaper, blowing your nose, or sneezing in your hands.


• Before and after eating or drinking or handling food, especially raw meat, poultry or fish.


• After contact with animals or animal waste. Wash up after playing with your pet or changing the kitty litter.


• After contact with garbage.


• Before and after contact with sick people.

Help prevent the spread of infectious illnesses. Wash your hands!

New guide from Quebec helps prevent unwanted exposure to dangerous drugs

Sometimes medication impacts the health of someone for whom it was not prescribed. Unintended exposure to harmful drugs, such as the antineoplastic drugs used in the treatment of cancer, can happen throughout the drug's life cycle in the hospital or at home.

Someone can be accidentally exposed to a drug while it is being:

• Prepared in a lab or pharmacy;


• Transported to a receiving dock or storage facility;


• Administered to the patient
;

• Eliminated through feces, urine or other excretions;


• Discarded in the garbage.

When the US National Institute for Occupational Safety and Health (NIOSH) published an alert in September 2004, it warned that any number of workers might be exposed to hazardous drugs. "These workers include shipping and receiving personnel, pharmacists and pharmacy technicians, nursing personnel, physicians, operating room personnel, environmental services personnel, and workers in veterinary practices where hazardous drugs are used."

Quebec institutions paid attention. The NIOSH document prompted a number of health care providers, associations and pharmacies in the province to question their preventive measures for the preparation and handling of hazardous drugs.

Meanwhile, the Association paritaire pour la santé et le securite du travail du secteur affaires sociales (ASSTSAS) - whose mission is to promote occupational health and safety in health and social services institutions - formed a Working Committee on the Safe Handling of Hazardous Drugs, which included professionals and stakeholders from the health care network, including the Institut de recherche Robert-Sauvé en santé et en sécurité du travail (IRSST).

The Prevention Guide - Safe Handling of Hazardous Drugs sets out the Committee's recommendations regarding how to safely handle hazardous drugs. While mostly intended for health care workers, the guide includes recommendations that also apply to users of the health care network and their families. Its creators have included sample procedures with illustrations, forms and checklists, as well as photos and charts.

The guide refers to practices that may present a risk of exposure to people who work closely with, or at a distance from these drugs. Its recommendations are consistent with those in most guides published in North America, Europe and Australia. The ASSTSAS may publish updates in future to supplement or clarify issues that might require further research.

The majority of Canadian workplaces have some form of health and safety committee, which is required by law in many jurisdictions. Even in workplaces where it is not mandatory, voluntary committees have been established, as workers and employers alike recognize the benefits in addressing workplace health and safety needs.

A health and safety committee serves in an advisory capacity, representing the interests of both management and workers, and is not a body responsible for enforcing legislation. With the right support and commitment, and when run efficiently, a committee can have a positive impact on a company's safety record and culture.

To help both new and established committees operate efficiently and function effectively, CCOHS has developed a recorded webinar series, Learning by Committee.

The first webinars in the series focus on two core responsibilities of health and safety committees: holding regular meetings, and addressing workplace hazards.

Success of a committee depends heavily on the conduct and procedures of its meetings. In Effective Committees, members will understand their roles and responsibilities, learn how to structure a meeting, and receive tips for making health and safety recommendations and responding to concerns.

Certain workplace conditions and work practices have the potential to cause accidents and injuries or increase the risk of illness. The second installment of the series, Workplace Hazards, focuses on a committee's responsibilities with respect to activities and processes that could potentially result in accidents, injuries and harmful exposure at the workplace. Members will learn how to identify types of hazards, review methods of hazard recognition, and understand the importance of reporting hazards.

Each 35-minute session is designed to inform and inspire committee members into action and be used as educational sessions at their health and safety meetings. Because they are recorded, members can pause to review key information, or to discuss concepts as they apply to their organization.

When you register for a webinar you get unlimited 30-day access to view the presentation, plus a downloadable toolkit with presentation slide handouts, sample templates, and forms that you can customize for your own use. To play the webinars in the meeting, committees will need a computer with speakers or a sound card, and Windows Media Player 9, plus a projector or large display screen. No additional software is required.

Watch for additions to the series coming soon.