Understanding multiple chemical sensitivities
Multiple chemical sensitivity (MCS) is a term proposed by Cullen (1987), and described as an “acquired disorder characterised by recurrent symptoms, referable to multiple organ systems”. These adverse reactions occur in association with exposure to diverse environmental triggers such as food, inhalants, or industrial chemical additives, at concentrations far below those established in the general population as harmful.
People living with chemical hypersensitivity experience a range of symptoms in different body systems. The resulting health problems lower quality of life, and can result in loss of bodily or mental functions. Triggers include a variety of food (such as gluten, spices, pork, tomatoes), inhalants (such as essential oils, synthetic perfumes, mould or pollen spores), and industrial chemical additives (such as preservatives and colours used in food, cosmetics, and drugs).
Any body system may react from any manner of exposure. For example, inhalation of toxicants can lead to muscle aches. Reactions to triggers range from mild (such as slight headache, sneezing, minor heartburn) to severe (such as panic attack, chronic diarrhoea, incapacitating fibromyalgia). Reactions may occur within minutes to an hour, or be delayed and develop over time from initial exposure.
Health problems from exposure to triggers
Neurological — dizziness, seizures, migraines, fainting, and loss of coordination
Respiratory — asthma, difficulty breathing, coughing, and shortness of breath
Dermal — rashes, hives, red skin, tingling skin, dermatitis
Cognitive — difficulties thinking, concentration and memory difficulties
Mucosal — sneezing, nasal congestion, red eyes
Immune — swollen lymph glands, fever, fatigue
Gastrointestinal — nausea, bloating, diarrhoea
Cardiovascular — fast or irregular heartbeat, jitteriness, chest discomfort
Musculoskeletal — joint pain, cramps, muscle weakness
…researchers recommend identification and avoidance of triggers specific to the individual, in order to effectively reduce the toxic burden and thus improve tolerance over time.
The level of intolerance is thought to parallel the total burden of bioaccumulated toxins. Once an individually variable threshold for toxicants is reached, tolerance is diminished and continues to weaken with prolonged exposure to toxicants. When the toxic burden is high, individuals can lose tolerance of even recently tolerable foods. Treatments in sensitivity-related illness commonly control symptoms, such as medications that relieve heartburn or headaches, and psychological interventions that aim to cognitively retrain responses. Other researchers and clinicians recommend identification and avoidance of triggers specific to the individual, in order to effectively reduce the toxic burden and thus improve tolerance over time.
Those who believe chemical exposure resulted in their illness often feel disbelieved and dismissed when medical practitioners conclude that their triggers do not exist.
Despite decades of discussion in the scientific literature and recent laboratory and animal evidence, the medical and scientific community remains resistant to the existence of sensitivity-related illness. As yet, no consensus has been reached in understanding the underlying cause of hypersensitivity, nor is there diagnostic testing for all sensitivities. Those who believe chemical exposure resulted in their illness often feel disbelieved and dismissed when medical practitioners conclude that their triggers do not exist. Although such varied and dissimilar responses to diverse groups of triggers are difficult to study and treat, the undoubtedly profound experiences of hypersensitive people is increasingly prevalent in adults and children in many countries. In Australia, 3 million adults are diagnosed with MCS or report chemical sensitivity. In America, 3–4% of the population suffers from severe symptoms and about 15–30% exhibit milder symptoms. Cases of sensitivity-related illness is similarly increasing in Canada and the European countries.
Dr. Stephen Genius, a clinician and researcher in environmental medicine suggests that sensitivity-related illness is associated with the bioaccumulation of toxins, a result of modern society’s widespread exposure to chemical pollutants in our environment.
Evidence for sensitivity-related illness
Scientific literature details clinical presentations of individuals hyper-responding to a diverse group of environmental triggers, and importantly, improving when the trigger is eliminated. In a case study of a 10 year old with worsening arthritis in multiple joints and years of specialty paediatric therapies, elimination of common chemical and food triggers had nearly extinguished all joint pain, swelling, and gastrointestinal problems within 4 weeks. However, inconsistency in the elimination of common triggers was observed overtime. Upon investigation for a primary toxicant, researchers identified mould in the child’s bedroom, and elimination of the mould finally allowed the child to play pain-free for the next 18 months until the study ended. Research on the effects of widely used additives on humans and animals evidenced their pro-inflammatory and carcinogenic effects. An experiment published in 2019, reported evidence of anxiety and reduced social behaviour in rats that ingested dietary emulsifiers for 12 weeks compared to the water-drinking controls. Bioaccumulation of widely used additives, such as titanium dioxide, have been measured in the increased sensitivity of the offspring of fleas whose parents were exposed to titanium dioxide compared with the offspring of unexposed adults. Dr. Stephen Genius, a clinician and researcher in environmental medicine suggests that sensitivity-related illness is associated with the bioaccumulation of toxins, associated with modern society’s widespread exposure to chemical pollutants in our environment.
Management of MCS-related symptoms has mostly focused on symptom control through pharmaceutical or psychological interventions. For example, pain relieving medications, or mindfulness therapy to alleviate the stress of living with a chronic condition. However, given the growing body of evidence, it appears negligent to not explore treatments that identify environmental toxins and their effects, so as to methodically eliminate triggers and over time, reduce the toxic burden and improve health.