Healthcare Access for Adults with Multiple Chemical Sensitivity in Canada: A Descriptive Online Cross-Sectional Survey

Multiple chemical sensitivity (MCS) is a chronic condition characterized by adverse multisystem reactions triggered by chemical exposures, including at low levels. The use of fragranced and disinfectant products within healthcare institutions was frequently reported by individuals with MCS as a challenge to accessing healthcare. This study was conducted during the COVID-19 pandemic, when infection control measures may have intensified the pre-existing chemical-exposure barriers for people with MCS. This study examines healthcare access among adults with MCS in Canada, including access to diagnosis and physicians and satisfaction with in-person and virtual care. A national cross-sectional online survey was conducted between January and February 2021 among adults living with MCS for at least one year prior to the pandemic. Quantitative and open-ended questions captured experiences related to diagnosis, access to physicians, and satisfaction with virtual and in-person healthcare. Of the 119 participants who completed the survey, most reported having a formal diagnosis of MCS (78.2%, n = 93, 95% CI 69.9–84.6). Among those who could not obtain an MCS diagnosis (N = 26), common barriers included obtaining any other diagnosis but MCS (61.5%, n = 16; 42.5–77.6), and the belief among medical professionals that MCS does not exist (57.7%, n = 15; 38.9–74.5). Among participants who gave reasons for dissatisfaction with virtual care (n = 32), 87.5% (71.9–95.0) cited the clinician’s lack of understanding of the condition, whereas technical problems were rarely reported (12.5%, 5.0–28.1). Among participants who reported dissatisfaction with in-person care (n = 41), 85.4% (71.6–93.1) cited the clinician’s lack of understanding of the condition, and 85.4% (71.6–93.1) cited chemical exposures, including scented disinfectants, soaps or sanitizers, while 80.5% (66.0–89.8) cited cleaning products on surfaces. Participants’ responses suggest that pandemic-related public health responses intensified pre-existing barriers to care for people with MCS by increasing chemical exposures and constraining access to knowledgeable providers. These findings highlight the need for healthcare systems and emergency preparedness frameworks that integrate chemical safety, disability inclusion, and provider education to ensure equitable access, including during public health crises.