Environmental Health Clinic

The Environmental Health Clinic (EHC) is a unique multidisciplinary clinic and the only one of its kind in Ontario. It was established in 1996 by the Ministry of Health and Long-Term Care to be a provincial resource in promoting environmental health and to improve health care for people with chronic complex environmentally-linked conditions such as Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), Fibromyalgia Syndrome (FMS) and Environmental Sensitivities, including both Multiple Chemical Sensitivity (ES/MCS) and Electromagnetic Hypersensitivity.

The Environmental Health Clinic was established to be the clinical part of a joint clinical and research program of Women’s College Hospital and the University of Toronto.

Contact Info

77 Grenville St.
Main floor, Room 101
Toronto, ON M5S 1B3

Phone: 416-351-3764
Toll-Free: 1-800-417-7092
Fax: 416-323-6130

Monday to Thursday
8:30 a.m. – 4:30 p.m.

The purpose of the clinic is to:

  • Educate our clients, the public and health-care professionals about environmental health issues.
  • Provide a comprehensive assessment for clients with complex chronic multisystem conditions such as ES/MCS, ME/CFS and FMS and to make recommendations to their treating physicians regarding the management of their ongoing health care needs.
  • Gain a better understanding of the health-care needs of those with these chronic complex multisystem conditions through participation in clinical research.

Care has been taken to ensure that the clinic does not contain substances that give off odorous gases, such as fresh paint, carpeting, tobacco smoke and scented cleaning products.

In consideration of others, please do not wear colognes, perfumes or use scented products on your appointment day.

Smokers must abstain from smoking for 24 hours and wear thoroughly washed clothes prior to their appointment

We are currently trying to gather information that will help improve quality of care at the EHC. We would appreciate you completing this anonymous survey. Individuals will have the opportunity to have their voices heard to shape future care for those with environmental illness. Please see the survey link below:

Women’s College Hospital Environmental Health Clinic Quality and Impact of Care Survey

ES-MCS Sensitivities Status Report
For a more in-depth analysis of knowledge advancement and the identification of service gaps in Environmental-Multiple Chemical Sensitivites, read this 2011 Status Report (.pdf) developed by the Environmental Health Clinic.


Physician referral is required. Blood work is required as part of the referral process. Learn more about the Referral Process below.

We provide a comprehensive assessment, by a nurse and doctor, and offer suggestions and information to help improve the health of patients referred to our program. The initial assessment takes approximately three hours. One to two shorter follow-up virtual appointments are offered to complete the assessment. We may refer you to medical specialists or to other health care professionals for consultation.

We send a comprehensive written report, outlining our assessment findings and suggestions for care, to the referring physician, usually the family doctor, who is responsible for management of ongoing health care needs.

Please fax your referral to the Environmental Health Clinic at 416-323-6130

We require a written referral from your primary care provider before we make a clinic appointment for you. If you do not have a primary care provider, please make an appointment with a family doctor of your choice to establish ongoing care and obtain a referral. The Environmental Health Clinic does not provide ongoing care to clients. Blood work is required as part of the referral process.

Your primary care provider will receive a written report outlining our assessment findings and suggestions for your care. Your primary care provider is responsible for follow-up on the suggestions made by the Environmental Health Clinic for managing your health care.

Pre-visit Questionnaire

We will ask you to complete and return a pre-visit questionnaire before a clinic appointment is made for you. The questionnaire provides the opportunity for you to describe your medical history in a complete, organized way and to assist the clinic staff in planning for your visit.

If you have questions or difficulties when completing the questionnaire, the clinic nurse will be pleased to help you.

Laboratory Tests

According to the evidence-based scientific literature, in agreement with the Environmental Health Clinic’s physicians, laboratory screening to rule out other conditions is advisable before you are seen at the clinic.


You will be notified when an appointment is made for you. Appointments will bein person or conducted virtually via telephone or video visits. Expect your initial appointment to take several hours. One to two shorter follow-up appointments will be offered to complete your assessment. Our waiting list for new referral appointments is approximately one year.


For your initial appointment please have a list of prescription and non-prescription medications and vitamin/mineral supplements you are currently taking (or an updated list).


The cost of all visits to the clinic is covered by OHIP.

Here is some additional information from our experts at Women’s College Hospital that can help provide answers to many questions you may have about Environmental Health.

Prior to your appointment, please complete the Exposure History

Women are affected by environmentally linked illnesses far more than men are. Eighty to ninety percent of those afflicted with environmental sensitivities, chronic fatigue syndrome/myalgic encephalomyelitis and fibromyalgia, also pegged as “21st century illnesses,” are women.

The causes of these conditions are unknown. However, researchers suspect that there are a number of factors at work.

Learn More

Chronic fatigue syndrome (CFS), also known as myalgic encephalomyelitis (ME), is a chronic condition characterized by debilitating fatigue and an array of other symptoms. It is estimated by the Canadian Community Health Survey (2005) that at least three percent of Canadians have been diagnosed with the condition and many more cases likely go undiagnosed. CFS/ME is far more prevalent among women, and usually affects people in their 40s and 50s but can affect a person of any age.

Learn More

Fibromyalgia is a chronic condition characterized by fatigue and widespread musculoskeletal pain that is present above and below the waist especially in “tender points.” Symptoms can also include mental processing problems, for example, problems with short-term memory and concentration, headaches, sleep disorders, heat/cold intolerance, anxiety or emotional numbness, heart problems, including rhythm abnormalities, and marked weight change.

Learn More

Environmental sensitivities (ES) describes a chronic condition whereby a person has symptoms when exposed to certain chemicals or other environmental agents at low levels tolerated by most people. The symptoms may range in severity from mild to debilitating.

Learn More

On May 31st, 2019 a symposium was hosted by the Environmental Health Clinic at Women’s College Hospital entitled: Impacts of Wireless Technology on Health: A symposium for Ontario’s medical community.

Preliminary Clinical Practice Guidelines for EHS (.pdf)

Proceedings from a Symposium on the Impacts of Wireless Technology on Health (.pdf)

The symposium consisted of presentations and interactive group discussion about the impact of wireless technology on health. Speakers included clinicians, medical researchers, patient advocates and technicians discussing the demographics, toxicology, epidemiology and pathophysiology or wireless technology, current best practices for management of illness, up-to-date research and the lived experiences of patients.

Here is the link to view the talks presented on that day:

On a typical day, most of us are exposed to a wide variety of potentially toxic substances while simply going about our regular routines at home, at school, at work and in our communities. For example, we can breathe in chemicals that “off-gas” from our furnishings, from dry-cleaned clothes, scented personal care products and harsh cleaning products. We can eat pesticide residues on foods. We can encounter biological agents like bacteria, viruses, dust mites and mould in indoor air, as well as electromagnetic radiation from computer monitors, cell phones and microwaves. We can come into contact with toxins by breathing, touching, eating or drinking them.

Learn More

Allergen – a substance that causes an allergic reaction. Allergens stimulate the body’s immune system to produce antibody proteins, to counteract the allergen. Examples of common allergens include dust, pollen, pet dander and mould.

Allergy – an exaggerated immune response to allergens, such as insect venom, dust mites, pollen, pet dander, drugs or some foods.

Analgesic – a medication that relieves pain.

Arthritis – there are more than 100 different kinds of arthritis. These diseases affect not only the joints but also other connective tissues of the body, including muscles, tendons and ligaments, as well as the protective covering of internal organs.

Autoimmune Disease – a disease in which the immune system destroys or attacks the patient’s own body tissue.

Autonomic Nervous System – the part of the nervous system that regulates key automatic bodily functions, including the activity of the heart muscle and smooth muscles such as the gut.

Bioaccumulation – the accumulation of substances from the environment by animals and plants over time. A number of pollutants (see persistent organic pollutants) can be stored for years in human body fat and can be discharged in a woman’s breast milk.

Biofeedback – a technique that uses electronic monitoring equipment to train people to control bodily functions which are normally automatic, for example, their blood pressure, heart rate or muscle tension.

Birth defect – any structural, functional or biochemical abnormality (genetically determined or acquired during pregnancy) not due to injuries suffered during birth.

Body Burden – the total amount of toxins that have built up over time in a person’s body.

Brain Fatigue – also referred to as “brain fog.” This term is sometimes used by patients with chronic fatigue syndrome, fibromyalgia and environmental sensitivities, to describe difficulty concentrating, thinking and remembering, and a dull, groggy or “spacey” feeling.

Chronic Disease – an illness that lasts for a long time.

Chronic Fatigue Syndrome – a chronic condition characterized by fatigue, post-exertional malaise and/or fatigue; can also cause headaches, sore muscles, joint pain and fever; not directly caused by other conditions. People with chronic fatigue syndrome are not able to fully participate in their ordinary activities.

Cognitive – relating to conscious intellectual activity (such as thinking, reasoning, remembering, imagining or learning words).

Cognitive Behavioural Therapy – a form of psychotherapy that emphasizes the importance of finding new ways of thinking and behaving to deal with current problems, such as depression or anxiety.

CPAP (continuous positive airway pressure) – a device used to treat moderate to severe sleep apnea. The machine sends air at a constant, continuous pressure to help keep a person’s airway open, allowing the patient to breathe normally.

Cumulative Toxic Effects – the result of a build-up of a toxin or a number of toxins over time in the body, as a person is repeatedly or continuously exposed.

Dioxins – highly toxic chemicals which are by-products of incineration or chlorine bleaching. More than 90 percent of human intake of dioxins is from food, especially animal fats, herbicides and pesticides. Acute health effects include headaches and nausea. Cancers, diabetes, liver disease, heart disease, fatigue and nerve and reproductive damage have been reported in humans exposed to high levels.

Endocrine Disrupters – chemicals that affect the endocrine system and prevent hormones from performing their usual functions in the body. Exposure to endocrine disrupters during critical stages of development can result in permanent effects on overall health, intelligence and the ability to reproduce. Examples of endocrine disrupters include PCBs, some pesticides, dioxins and phthalates.

Endocrine System – the system of glands that regulates a person’s mood, growth, sexual function, reproductive processes and metabolic activity. The endocrine system includes the pituitary gland, thyroid, parathyroids, adrenal glands, pancreas, ovaries (in women) and testes (in men).

Environmental Contaminants – potentially harmful substances that have been released into the environment and have entered our food, water, air and soil.

Fibromyalgia – a chronic condition that causes pain and stiffness throughout the tissues that support and move the bones and joints. Pain and localized tender points occur in the muscles, particularly those that support the neck, spine, shoulders and hips. The disorder includes widespread pain, fatigue and sleep disturbances.

Flare-up – a period in which the symptoms of a disease reappear or worsen.

Heavy Metals – dense metals of high relative atomic mass, such as lead, cadmium and mercury. Heavy metals can accumulate in the tissues and are toxic beyond certain levels, which vary from person to person.

Hidden Exposures – exposures to toxins or environmental contaminants that people are unaware of. Exposures occur by breathing in, eating, drinking, touching or injecting a substance.

Immune Response – the reaction of the immune system against foreign substances. When this reaction occurs against substances or tissues within the body, it is called an autoimmune reaction.

Immune System – a complex system that normally protects the body from infections and environmental contaminants. It is comprised of groups of cells, the chemicals that control them, and the chemicals they release.

Inflammation – a reaction of tissues to injury or disease, marked by swelling, redness, heat and pain.

Ligaments – bands of cord-like tissue that connect bone to bone.

Malaise – a general feeling of unease or lack of health, often accompanying the onset of an illness. Post-exertional malaise follows either physical or mental activity.

Musculoskeletal – referring to the muscles, tendons, ligaments, cartilage, bones, joints and spinal discs.

Myalgic Encephalomyelitis – the British term for chronic fatigue syndrome.

Neural Tube Defect – abnormal development of the neural tube in utero, resulting in a birth defect, such as spina bifida or anencephaly. Between two and four of every 1000 babies born in Canada have neural tube defects. When a woman takes vitamins with folic acid before and during pregnancy, she reduces her chance of having a baby born with a neural tube defect.

Neuroendocrine – relating to the interactions between the nervous and endocrine systems.

Neurologic – referring to the brain and central nervous system. The “central” nervous system is comprised of the brain and spinal cord. The “peripheral” nervous system is the nerve tissue that transmits sensation and motor information back and forth between the body and the central nervous system.

Nonsteroidal Anti-inflammatory Drugs (NSAIDs) – a group of drugs, such as aspirin and ibuprofen, used to reduce inflammation.

Obstructive Sleep Apnea – a sleep disorder with symptoms of loud snoring and periodic pauses in breathing, which last for at least 10 seconds, after which breathing is resumed again with a snort.

Off-gas – to give off fumes. Substances such as solvents, paints, certain cleaning products, plastic materials (e.g., shower curtains) and pesticides “off-gas.”

PCBs (polychlorinated biphenyls) – a class of highly toxic synthetic chemicals that were used from 1929 to 1979 in North America, in industrial materials, and in transformers and other electrical equipment. The manufacture and importing of PCBs were banned in 1979, in North America, due to their environmental persistence, bioaccumulation in fatty tissues and potential health risks. They are still found in foods and the environment (water systems, landfills and hazardous waste sites). PCBs can be toxic to the liver and skin, and can cause cancer.

Periodic Limb Movement Disorder – a sleep disorder characterized by periodic episodes of repetitive jerking and kicking during sleep. The movements are often associated with a partial arousal or awakening; however, the person is usually unaware of the limb movements or frequent sleep disruption. Also known as nocturnal myoclonus.

Persistent Organic Pollutants – pollutants that remain in the environment for a long period of time, are stored in fat, and are toxic. Examples of POPs include dioxins, PCBs, lead, arsenic, cadmium, mercury and chlorinated pesticides.

Precautionary Principle – a moral principle used to guide decisionmaking and prevent harm: When there is an activity or product that could threaten human health or the environment, precaution should be taken, even before there is scientific proof that the activity or product is harmful. The precautionary principle advises caution in the context of uncertainty. It is often applied, for example, in the realms of environmental policy and health care.

RAST test – the RAST (radioallergosorbent test) is an allergy test done with a blood sample. It tests for the amount of specific antibodies in the blood to specific substances.

Referred Pain – pain that arises in one part of the body but is felt in another.

Remission – a period during which the symptoms of a disease are reduced (partial remission) or disappear (complete remission).

Restless Leg Syndrome – a sleep disorder characterized by numbness, tingling, restlessness and a creeping feeling in the legs. Restless leg syndrome is relieved by stretching or walking.

Skin or Scratch or Prick Test – an allergy skin test used to identify the substances that are provoking an allergic reaction. It is performed by applying an extract of an allergen to the skin, scratching or pricking the skin to allow exposure, and then evaluating the skin’s reaction.

Sleep Disorders – a broad range of difficulties related to sleeping. A person may have difficulty falling asleep (insomnia), difficulty staying asleep, difficulty staying awake (narcolepsy) or other disruptive sleep patterns. Sleep disorders have many causes, such as stress, physical illness, abnormalities of the biological clock, drugs and medications, and sleep disturbances that contribute to difficulty achieving restful, restorative sleep.

SSRIs (selective serotonin reuptake inhibitors) – a class of drugs used to treat depression. SSRIs block the reuptake of the neurotransmitter serotonin by neurons. Examples include fluoxetine (Prozac), sertraline (Zoloft), paroxetine (Paxil) and fluvoxamine (Luvox). These medications seem to have fewer side effects and may be more effective for women than many of the older antidepressants.

Synergistic Effects – effects of a combination of two or more substances that are greater than the sum of the effects of the individual substances. Very little is known about the synergistic effects of our exposures to common chemicals.

Tender Points – specific locations on the body that are exceptionally sensitive when pressed.

Tendons – fibrous cords that connect muscle to bone.

TENS (transcutaneous electrical nerve stimulator) – A TENS unit is a small electronic device that can be used to relieve pain. Electrodes are placed on the skin and used to deliver painless low-voltage electrical impulses to the nerves nearby.

Toxin – a poison produced by a living organism, such as a plant, animal or micro-organism.

Tricyclic Antidepressants – an older class of drugs used to treat depression. Examples include amitriptyline (Elavil), nortriptyline (Pamelor), imipramine (Tofranil) and desipramine (Norpramine). These medications may have more side effects than newer antidepressants (see SSRIs), but have advantages for some people. They can also relieve chronic pain. Tricyclic antidepressants are sometimes used, in low doses, to induce sleep.

Volatile Organic Compounds (VOCs) – gasses emitted from certain solids and liquids, which can have adverse short- and long-term effects on human health. The thousands of chemicals that are considered VOCs are emitted from products such as paints, paint strippers, varnishes, glues, pesticides, furnishings, building materials, carpet, plastics, gasoline, cigarettes, air fresheners, dry-cleaned clothing, and office equipment, such as photocopiers and printers. VOC levels are generally several times higher indoors than outdoors.