What is Multiple Chemical Sensitivity or MCS

According to the Ontario Centre of Excellence in Environmental Health, Multiple Chemical Sensitivity is a central nervous system disorder and detoxification dysfunction that can range from mild to severe, and can affect any organ systems.

What does that mean exactly? Think back to the last time you battled a nasty virus. You may remember experiencing normal immune system reactions: extreme fatigue, head and body aches, runny nose, an uncontrollable cough.

Now imagine that you had a reoccurrence of these physical symptoms whenever you came in contact with a person wearing perfume. Or when walking by the bathroom being sanitized at your workplace. Or visiting a home that uses plug-in fragrance.

People who suffer from the chronic condition, Multiple Chemical Sensitivity or MCS are dealing with these situations regularly.

Other Names for MCS

MCS has been called many different names around the world over the course of history. This makes researching the condition difficult. Here are some alternate names for MCS:

• Environmental Sensitivity (ES)
• Idiopathic Environmental Intolerance (IEI)
• Chemical Sensitivities
• Chemical Intolerance
• Sick Building Syndrome
• 20th Century Disease
• Total Allergy Syndrome
• Chemical Sensitivity Syndrome
• Toxicant Loss of Tolerance (TILT)

It also shares many commonalities with other conditions such as Electromagnetic Hypersensitivity, Chronic Fatigue Syndrome, Lyme Disease, Irritable Bowel Syndrome and Mast Cell Activation Syndrome.

Who Suffers from MCS

According to a 2018 study by Dr Anne Steinemann in the Journal of Occupational and Environmental Medicine, 25.6 million adults were diagnosed with MCS in the US. Another 51.8 million Americans reported a sensitivity to chemicals.

In Canada, over 1 million have been diagnosed with MCS as of 2021. Due to limited information available in the mainstream medical community and access to doctors specializing in this debilitating condition, the prevalence rates are estimated to be quite higher.

Symptoms of MCS

Unlike an allergy which can be diagnosed through medical testing, MCS is diagnosed through documenting the triggering of recurrent symptoms. These triggers, often referred to as “irritants” cause many of the same reactions as environmental allergies. Runny nose, sneezing, sore throat, coughing, is common but irritants can also produce other debilitating symptoms as well:

• headaches
• loss of mental clarity
• memory loss
• nerve pain
• nausea
• vomiting
• joint pain
• dermatological symptoms like rashes and hives
• respiratory distress like asthma attacks and anaphylaxis

Studies show that approximately 70% of MCS sufferers also have asthma or display asthmatic-like symptoms upon exposure to an irritant.

Irritants That Cause Reactions

Irritants include a wide range of things in the environment from wood or tobacco smoke, gas and diesel fumes, organic solvents, mold toxins and chemical exposure.

Synthetic fragrances contain chemical irritants that cause severe reactions in MCS sufferers. Because fragrance is used in just about everything from personal care to cleaning products, it is very difficult to avoid.

Causes of MCS

There has been a lack of research into the causes of MCS in patients. There has yet to be an identified underlying cause. It is thought that there is a combination of factors that lead to a person becoming chemically sensitive. Some of these risk factors are:

• genetic predisposition
• strong initial exposure to petrochemical products
• continued exposure to lower levels of chemicals at home or the workplace
• environmental exposure to pesticides
• mold exposure
• chronic oxidative stress
• history of allergies, food sensitivity and food intolerances

What is the Toxic Load

The healthy human body is very efficient at ridding itself of toxins in the air, water and food. When the body is presented with a bombardment of toxins over a period of time, it has difficulty keeping up.

Picture toxic load being like a large barrel of water. Imagine carrying this barrel on your back. At the start, it is empty and very light. You are able to carry on with life quite normally.

But then you are exposed to a harsh chemical. Your body is trying to deal with flushing it out and so the barrel on your back begins to fill with water, say, 1/4 full. The barrel feels heavy but you are still able to carry it and do many of the things that you did before albeit with a little strain.

A while later, you catch a virus and fall ill. Your body is still trying to flush from the first exposure but now has to fight an invader. The barrel is now half full and getting heavy and you are tired carrying it.

Then you experience a loss in your life (marriage, job, loved one) and the stress from that event poured more water into the barrel. It’s now at 3/4 capacity. You are more tired, more restricted in what you were once able to do. But you keep going and trying to cope.

Finally, you walk into a public washroom where someone has sprayed fragrance and your barrel fills to capacity and spills over causing an acute asthma attack and a cascade of symptoms that are debilitating and long lasting.

This analogy shows that no one event or exposure caused the person’s state of health, rather a culmination of various factors took a toll on the person’s body to the point that it wasn’t able to cope. This also highlights why using the rationale: “this chemical never caused any problems in the past, then surely it cannot be a culprit causing symptoms now!” is problematic.

Reducing the Toxic Load

There are many things you can do to reduce the toxicity load on your body from everyday chemicals. Making these changes will benefit the body overall and help protect it from damaging effects of hazardous chemicals.

Remove Chemicals From the Home and Workplace

Replacing commercial cleaning products with safer cleaning alternatives makes a huge difference in reducing the daily exposure to harmful chemicals. If you want to research commercial cleaners and their ingredients, check out the Environmental Working Group website. They have excellent consumer databases available that rates the safety of many popular household products on the market.

Get Rid of Fragranced Consumer Products

Remove scented air fresheners, deodorizers, candles, wax melts, diffusers from your home and workspaces. Many people don’t realize that their favourite fragranced products are formulated with harmful chemicals. Chemical ingredients in these fragrances are protected by trade secret and as such, they are not required to be listed on a product.

Products marketed as “natural” or using essential oils in their formulas are not as safe as they appear. Often a host of chemicals have been added to bind or stabilize the scent.

Chemicals in fragranced products are not only problematic for people with asthma and MCS. They have been linked to breathing difficulties, migraines, hormone disruption, and infertility in the general population.

Examine Ingredients in Laundry Products

Replace scented detergents with fragrance-free and more natural products. Choose safer alternatives such as switching from dryer sheets to dryer balls. Any product that makes claims of long-lasting scent or “scent booster” should be discontinued.

Stop Using Fragranced Personal Care Products

Perfumes, aftershaves, scented lotions, soaps and hand sanitizers are some of the strongest fragranced products on the market. The scented product that you have built up a tolerance to could still be adding to your body’s toxic load.

Any product that lists “fragrance” as an ingredient has hidden chemical components that could be making you sick. Read this article from the NY Times about the dangers of harmful chemicals in personal care products.

There are plenty of safer alternatives on the market. EWG has a verified list of products that meet a high standard of safety. Read this post if you want some safer choices.

Improve Indoor Air Quality

Air quality at home and in your workplace can be improved greatly with HEPA air purifiers. You can also achieve this naturally by adding some live plants. Species like the Peace Lily, Boston Fern, Spider Plant, and Snake Plant have been proven to remove toxic air pollutants.

Choose Safer Building and Home Furnishing Materials

Hazardous elements such as formaldehyde and volatile organic compounds (VOCs) are present in construction materials, carpets and upholstery.

Products like paint, caulking, adhesives, epoxys, etc can be very problematic for people with MCS. Check out Building Biologist, Corinne Segura from My Chemical-Free House. She has built an extensive resource of home renovation materials on her site that are suitable for the environmentally sensitive.

Eat Organic Whole Foods

It is common for MCS sufferers to develop sensitivities to certain foods. It is difficult to discern whether it is the actual food or the pesticides used to grow the food that is the culprit. Eating thoroughly washed organic produce will help reduce the risk of chemical contamination and narrow down true sensitivities to the triggering food.

How to Get a MCS Diagnosis and Treatment

Finding a doctor that has expertise in diagnosing and treating Multiple Chemical Sensitivity is often the hardest part of having the illness. There is a lack of understanding and research in MCS. General practitioners are often not aware of resources available to refer the patient for diagnosis and care.

While there is no definitive diagnostic test for MCS, the QUEESI questionnaire helps provide a chemical sensitivity scale. It contains diagnostic criteria to help define the adverse effects of triggers as well as the severity of symptoms and the impact on a patients life and state of wellbeing.

Getting an MCS diagnosis is often necessary to avail of school and workplace accommodations. No-Scent policies and the implementation of healthy air quality equipment often require documentation. Residents of Canada and the US can find support in the following clinics:

The Integrated Chronic Care Service – Canada

Nova Scotia has one of the few clinics in Canada that diagnose and offer treatment in the area of MCS. The ICCS team help patients manage their MCS symptoms with a holistic and interdisciplinary approach.

This team comprised of physicians, nurses, nurse practitioners, occupational therapists, clinical dieticians, psychologists and psychotherapists. Together they help MCS patients navigate and self-manage their illness.

The Environmental Health Clinic – Canada

The Environmental Health Clinic (EHC) is a multidisciplinary clinic located in Toronto, Ontario that helps people with chronic environmentally-linked conditions.

University of Texas Health Centre – United States

The University of Texas Health Centre in San Antonio Texas has developed a program to help MCS sufferers. They don’t use the term MCS however but have rebranded the disorder to TILT: “Toxic-Induced Loss of Tolerance.

Environmental Health Centre – United States

The Environmental Health Centre – Dallas in Texas, USA is another facility that offers diagnosis and treatment of chronic health conditions such as chemical sensitivity along with food allergy, food sensitivity and food intolerance testing and management.

Important MCS Resources:

“Putting the Chemicals Back in Multiple Chemical Sensitivity” by lead author Varda Burstyn and collaborating author Maureen MacQuarrie for the Ontario Environmental Health Advocates Group

The Chemical Sensitivity Podcast

Dispatches from the Chemical Edge