International prevalence of chemical sensitivity, co-prevalences with asthma and autism, and effects from fragranced consumer products

Chemical sensitivity is a medical condition characterized by adverse health effects from exposure to common chemical pollutants and products. This study investigated the prevalence of chemical sensitivity in four countriesthe United States (US), Australia (AU), Sweden (SE), and the United Kingdom (UK). In addition, it investigated the co-prevalence of chemical sensitivity with medically diagnosed multiple chemical sensitivities (MCS), fragrance sensitivity (health problems from fragranced products), asthma/asthma-like conditions, and autism/autism spectrum disorders (ASDs). Using nationally representative population samples in each country, data were collected in June 2016 and June 2017 through on-line cross-sectional surveys of adults (n=4435). Results found that, across the four countries, 19.9% of the population report chemical sensitivity, 7.4% report medically diagnosed MCS, 21.2% report either or both, and 32.2% report fragrance sensitivity. In addition, 26.0% of the population report asthma/asthma-like conditions, of which 42.6% report chemical sensitivity and 57.8% fragrance sensitivity. Also, 4.5% of the population report autism/ASDs, of which 60.6% report chemical sensitivity and 75.8% fragrance sensitivity. Among individuals with chemical sensitivity, 55.4% also report asthma/asthma-like conditions, 13.5% autism/ASDs, and 82.0% fragrance sensitivity. Although the prevalence of chemical sensitivity across the countries is statistically different, its co-prevalences with other conditions are statistically similar. Results also found that, for 44.1% of individuals with chemical sensitivity, the severity of health effects from fragranced products can be potentially disabling. Further, 28.6% of those with chemical sensitivity have lost workdays or a job, in the past year, due to exposure to fragranced products in the workplace. Results indicate that chemical sensitivity is widespread across the four countries, affecting over 61 million people, that vulnerable individuals such as those with asthma and autism are especially affected, and that fragranced consumer products can contribute to the adverse health, economic, and societal effects.