Health and Safety ReportVolume 15, Issue 06

On Topic

Pests and Poisonous Plants in Seasonprint this article

It might start with something crawling down the back of your neck or a lingering, painful, burning scratch from a roadside weed that doesn’t go away. These unpleasant encounters with ticks, mosquitoes and giant hogweed can lead to diseases such as Lyme disease and West Nile virus, and lasting painful injuries that can come from exposure to giant hogweed. If you work outdoors this summer, know what to look for and be on the alert for these pests and poisonous plants.

Ticks and Lyme diseaseBlack-legged tick

Ticks have benefitted from a mild winter and their populations are on the rise this summer. Blacklegged ticks, also called deer ticks, can carry Lyme disease and live in forests, overgrown, leafy areas and near wooded areas. However, as their populations spread, it’s possible to be bitten outside of these locations. In 2015, nine provinces reported Lyme disease: British Columbia, Alberta, Manitoba, Ontario, Québec, New Brunswick, Nova Scotia, Prince Edward Island and Newfoundland and Labrador.

Tick bites are usually painless and can easily go unnoticed. Symptoms of Lyme disease vary and may initially resemble the flu – sore throat, fever, headaches, fatigue, congestion and stiffness. They can often include spasms or weakness, numbness or tingling, swollen lymph nodes and a skin rash that sometimes appears as a bull’s eye with reddish rings spreading from the bite site.

Lyme disease is not always easy to recognize so it’s important to consult your doctor if you think that you may have Lyme disease. In most cases antibiotics can effectively treat Lyme disease, especially when treatment begins early. Cases that reach the later stages of the disease, however, can be difficult to treat and some symptoms can persist or recur.

Preventing contact with both ticks and mosquitoes starts with wearing light-coloured clothing: long-sleeved shirts, long pants tucked into socks, and a hat when possible. Employers should provide workers with repellents containing 20-30% DEET or Icaridin to use on their skin and clothing for protection against ticks and mosquitos.

After working outside, check for ticks on and under clothing, especially after being in areas where ticks may live. Shower or bathe within two hours of being outdoors to wash away loose ticks. Wash and dry work clothes in a hot dryer to kill any ticks that may be present.

How to remove a tick

Removing ticks within 24-36 hours reduces your risk of infection with Lyme disease. Using needle-nose tweezers, firmly grasp the tick, as close to your skin as possible and pull the tick away from your skin with a steady motion without squeezing or twisting it as this can cause the harmful bacteria to be released into the body. Clean the area with soap and water. Put the tick in a sealed container or double zip lock bag and bring the tick to your doctor or your local health unit office to be sent for testing for Lyme disease.

Mosquitoes and West Nile Virus

Rain and cooler temperatures across many parts of Canada this spring have created ideal conditions for mosquitoes to breed and thrive. Along with the itch of those pesky mosquito bites comes the risk of infection with the West Nile virus. The key to reducing your risk of West Nile virus infection is to avoid being bitten by mosquitoes.

West Nile virus is a microorganism carried by infected mosquitoes.  The virus has been reported in British Columbia, Alberta, Saskatchewan, Manitoba, Ontario and Quebec, New Brunswick and Nova Scotia.

The symptoms of West Nile virus infection can begin 2 to 15 days following the bite of an infected mosquito. The majority of infections are mild and most people who become infected have no symptoms at all though some people may experience mild flu-like symptoms, such as fever, headache, and rash. In rare cases, symptoms can be much more severe.

Mosquitoes are most active between the hours of dusk and dawn. So if you are outside during these times, cover up and use insect repellent. Removing any stagnant water from work areas will also help to eliminate mosquito breeding grounds.

Giant hogweedGiant hogweed

Originally imported into Canada as an ornamental plant, giant hogweed is an invasive species of plant found in many provinces across Canada and can cause severe skin and eye reactions. It grows along streams and rivers, forming a dense canopy that overtakes native species and can also thrive along roadsides and railways, waste areas, fields, and vacant lots.

Giant hogweed is a very large perennial plant that lives up to its name. It has large leaves up to a metre across, stalks that can reach 6 metres in height, and has white-yellow flowers that are usually in a large cluster up to a metre across.

Although the size is impressive, the hazard giant hogweed poses to human health is just as big. If you come into contact with giant hogweed sap, your skin can become extremely sensitive to sunlight, resulting in severe burns and blisters. Affected skin and eyes will become inflamed and swollen up to two or three days later. Eye contact is painful and may result in temporary or permanent blindness.

When working near these plants, avoid getting sap on your skin. Cover your body from head to toe with protective, non-absorbent clothing made from synthetic, waterproof material: long-sleeved shirts and pants, gloves with long cuffs, boots and protective coveralls. Protect your eyes and your entire face.

If your skin or eyes react, see a doctor as soon as possible. If you do get sap on your skin, remove it as quickly as possible without rubbing and spreading it, by blotting with absorbent cloth or paper. Wash the affected area with dishwashing or other degreasing soap and lots of cool water.  For eye contact with hogweed sap, flush eyes immediately with water for at least 15 minutes and use ultraviolet (UV) protective sunglasses.

Toolbox talks and safety meetings are good opportunities to discuss Lyme disease, West Nile Virus, and giant hogweed with employees and coworkers. The very important first step is to be on alert for these summertime pests and poisonous plants.

You can find additional information and resources using CCOHS OSH Answers fact sheets.

CCOHS Fact Sheets:


Heat Illness: Prevention is Keyprint this article

June has already seen some regional heat warnings issued and there are predictions that parts of Canada will reach record temperatures over the summer. Heat is a serious occupational hazard for some workers particularly in the summer. Here are some tips for keeping cool and preventing heat illness.

Risks and Prevention

Did you know that an increase in body temperature of just a couple of degrees could affect your mental functioning? An increase of body temperature by a few more degrees can result in serious injury or death. Heat may also be the underlying cause of a workplace accident, a fall, or a heart attack.

Heat stress is a buildup of body heat generated either internally (by muscle use) or externally (by the environment) that affects your body's natural cooling system. Without proper precautions, this heat buildup can develop into heat exhaustion or heat stroke, a potentially fatal condition. As the internal heat increases, the worker's body temperature and heart rate rise and the body becomes overwhelmed. When it comes to heat illness - prevention is key.

Tips for Employers

Provide training. Take time to train your workers on the serious health risks of heat illness, how to avoid it, how to recognize the symptoms and what to do if it happens. 

Keep workers cool. Demonstrate your commitment to workers' health by allowing some flexibility in work arrangements during hot conditions. If possible, schedule heavy tasks, and work that requires personal protective equipment (PPE), for cooler times such as early mornings or evenings. Keep the work area cool, or provide air-conditioned rest areas. For workers on duty in the heat, provide plenty of water and encourage them to drink even if they don't feel thirsty, and to take frequent rest breaks.

Tips for Workers

Do not expect to tolerate the heat right away. It can take up to two weeks for a person to build up a tolerance for working in hot conditions. Adapt your work and pace to the temperature and how you feel.

Take breaks. A simple but potentially life-saving practice, taking a break to cool off in the shade helps prevent your body from overheating. Try for shade or take breaks in an air-conditioned building or vehicle. If you don't have a shady or cool place, reduce your physical efforts.

Keep cool. Stay out of the sun as much as possible. If your job includes some physically demanding tasks, try to save those for the early morning or late afternoon hours when the sun is less intense. Wear lightweight clothing. The risk of heat illness can be greater if you wear certain types of personal protective equipment. If necessary, consider also wearing a cooling vest to help keep your body temperature down.

Stay hydrated. This is essential. As a general guideline, drink one cup of water every 15 to 20 minutes.

Avoid alcohol and drugs. The effects of heat illness may be worse if you ingest drugs or alcohol. If you are on medication, read the label or talk to your doctor to understand how it might cause your body to react to the sun and heat.

Recognize the symptoms of heat stress in yourself and your co-workers. These symptoms include rash, cramping, fainting, excessive sweating, headache and dizziness. You may not see or feel the effects so always use the buddy system to monitor one another.

Heat Exhaustion and First Aid

The warning signs of heat exhaustion include heavy sweating, moist, clammy skin, dizziness, nausea, vomiting, headache, muscle cramps, extreme weakness or tiredness, fainting, and pale or flushed complexion.

Anyone with these symptoms should be moved to a cool place to rest. Get medical aid. Remove or loosen excess clothing (hard hat, boots, shirt, coveralls, etc.) and cool the victim with cold packs or wet cloths such as towels or sheets. If they are conscious, give them half a cup of cold water to drink every fifteen minutes. 

Heat Stroke and First Aid

Heat stroke is one of the most serious types of heat illness. Unless the victim receives quick and appropriate treatment, they can die as a result of heart failure, kidney failure or brain damage caused by excess body heat. 

Warning signs may vary but may include red, dry, hot skin (no sweating), a very high body temperature (above 41°C), dizziness or confusion, breathlessness and complete or partial loss of consciousness. Any person with signs or symptoms of heat stroke is in danger and needs to be hospitalized. Get immediate medical help. Meanwhile, move the victim to a cool place. Remove heavy clothing, and apply ice packs or cold, wet cloths to the neck, armpits, wrists and ankles and vigorously fan the body to increase cooling and reduce body temperature.

Heat illness is a serious but easily preventable health risk. By following these basic rules you can enjoy a safe, healthy summer.

More information:

Partner News

WHMIS 2015 Compliance Initiative Starts This Summerprint this article

The federal government updated WHMIS rules in 2015. WHMIS 2015 includes new definitions, new harmonized criteria for hazard classification, and new rules for supplier labels and safety data sheets (SDSs). Suppliers and employers importing hazardous products for use at their workplace and/or selling (including distributing) hazardous products are required to keep “specific purchasing and/or sales information” for six years after the end of the year to which they relate. Those who manufacture and sell hazardous products must keep “specific sales information”.

To increase WHMIS 2015 awareness, Health Canada is planning a WHMIS 2015 compliance and enforcement initiative for the 2017-2018 fiscal year (April - March). 

From July-September 2017, select employers and suppliers in federal, provincial and territorial jurisdictions will receive a compliance promotion package, which contains information helpful to understanding the new WHMIS 2015 requirements. Some of these resources are listed below.

From October 1, 2017 to December 31, 2017 specially designated Hazardous Products Act (HPA) inspectors may visit your workplace to inspect and promote compliance. Inspectors may request a copy of your “specific purchasing information” and/or your “specific sales information,” and up to five SDSs/labels for your hazardous products. Inspectors may not provide advance notice of the inspection.

Contact CCOHS or for inquiries.

For WHMIS updates visit


Free WHMIS 2015 Training and Resources from CCOHS:


Podcasts: Brain Injury Awareness: An Interview with Dr. Angela Colantonio and Staying Afloat with Lifejackets and Personal Flotation Devicesprint this article

This month’s podcasts feature an interview with Dr. Angela Colantonio about brain injury awareness and an encore presentation of Staying Afloat with Lifejackets and Personal Flotation Devices.

Feature Podcast: Brain Injury Awareness: An Interview with Dr. Angela Colantonio

June is Brain Injury Awareness Month. In conversation with the Canadian Centre for Occupational Health and Safety (CCOHS), Dr. Angela Colantonio, Director of the Rehabilitation Sciences Institute at the University of Toronto, discusses brain injuries common in the workplace, how they affect men and women differently, workplace accommodation, and factors to consider for people returning to work after suffering a brain injury.

The podcast runs 7:30 minutes. Listen to the podcast now.


Encore Podcast: Staying Afloat with Lifejackets and Personal Flotation Devices

According to the Canadian Red Cross, wearing a lifejacket could eliminate up to 90% of all boating-related drownings. CCOHS discusses the difference between lifejackets and personal flotation devices, and how to use them safely.

The podcast runs 6:07 minutes. Listen to the podcast now.


CCOHS produces free monthly podcasts on a wide variety of topics designed to keep you current with information, tips, and insights into the health, safety, and well-being of working Canadians. You can download the audio segment to your computer or MP3 player and listen to it at your own convenience... or on the go!

See the complete list of podcast topics. Better yet, subscribe to the series on iTunes and don't miss a single episode


CCOHS Releases White Paper on Risk of Impairment from Cannabisprint this article

When workers are impaired on the job, it can have serious consequences. There are many sources of impairment such as fatigue, use of drugs (over the counter, prescription, illicit), and consumption of alcohol.  With the sale and use of recreational cannabis set to become legal in Canada by July 1, 2018, there are questions about how this could potentially impact the workplace. This is also an opportunity for employers to review their current workplace policies and programs and identify areas of improvement.

CCOHS has published a new white paper, Workplace Strategies: Risk of Impairment from Cannabis, that discusses the implications associated with the use of cannabis for both therapeutic and recreational purposes. It suggests that the key steps to reducing the impact of impairment on the workplace are to have appropriate mechanisms in place, to provide clear guidance to all workplace parties, and to apply workplace policies and programs using a fair and consistent approach.

This white paper presents information and recommendations for employers, employees, and others interested in workplace health and safety including how to:

  • address the potential for impairment as part of a hazard assessment,
  • establish a concise policy and program on the use of any substance that can cause impairment,
  • determine the actions the workplace will take regarding impairment,
  • implement accommodation practices where necessary (including for therapeutic needs and substance dependence), and
  • create a supportive healthy and safe workplace. 

The white paper was authored by CCOHS and underwent a tripartite review by representatives from government, employers and labour. It is available in English and French.

Download the white paper: Workplace Strategies: Risk of Impairment from Cannabis.


Additional CCOHS resources:

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