Toxicant-induced loss of tolerance for chemicals, foods, and drugs: assessing patterns of exposure behind a global phenomenon

Abstract

Background Despite 15–36% of the U.S. population reporting Chemical Intolerances (CI) or sensitivity, the condition has been overlooked in medicine and public health. CI is characterized by multisystem symptoms and new-onset intolerances that develop in a subset of individuals following a major chemical exposure event or repeated low-level exposures. While Toxicant-Induced Loss of Tolerance (TILT) is a two-stage disease mechanism proposed to explain CI, less is known about the exposures that initiate the disease, than about the intolerances that have been documented. Methods We reviewed eight major exposure events that preceded onset of chemical intolerance in groups of individuals sharing the same exposure. Our goal was to identify the chemicals and/or groups of chemicals that were most pervasive during each exposure event as well as identify the concentrations of key chemicals involved in each exposure event and the proportions of exposed individuals who ultimately developed TILT following exposure. Case studies we selected for review included (1) workers at U.S. Environmental Protection Agency (EPA) headquarters during renovations; (2) Gulf War veterans; (3) pesticide exposure among casino workers; (4) exposure to aircraft oil fumes; (5) the World Trade Center tragedy; (6) surgical implants; (7) moldy environments; and (8) tunnel workers exposed to solvents. Results Mixed volatile and semi-volatile organic compounds (VOCs and SVOCs), followed by pesticides and combustion products were most prevalent across TILT initiation events. As a broader category, synthetic organic chemicals and their combustion products were the primary exposures associated with chemical intolerance. Such chemicals included pesticides, peroxides, nerve agents, anti-nerve agent drugs, lubricants and additives, xylene, benzene, and acetone. Conclusion A select group of exposures were predominant in several major initiating events, suggesting their potential role in TILT initiation. Such insights are useful to public health scientists, physicians, and policymakers seeking to minimize harmful exposures and prevent future disease.

Mast cell activation may explain many cases of chemical intolerance

“…Chemical, food, and drug intolerances are growing international concerns [1][2][3][4][5]. These intolerances may arise following exposures to building construction or remodeling, pesticides, military environments (e.g., Gulf War), combustion products (e.g., World Trade Center disaster, burn pits, wildfires), chemical spills or releases, surgical implants, mold, and many other sources [6,7]. The exposures may be a one-time acute event; a series of exposures; or long-term, low-level exposures.…”

“…Many patients attribute onset of their illness and intolerances to a well-defined exposure event [7,8]. (Readers are directed to this study's companion paper addressing CI initiating events [7]).…”

Chemical Composition, Antibacterial, Antioxidant and Enzyme Inhibitory Activities of the Essential Oil from Leaves of Psidium guajava L.

“…However, the more severe problems caused by the use of pesticides are plant resistance, pesticide Supporting information for this article is available on the WWW under https://doi.org/10.1002/cbdv.202100951 doi.org/10.1002/cbdv.202100951 residues, and environmental pollution. [11] The most considerable disadvantage of biological control is that it is slow, unstable, and unable to cope with the sudden increases in diseases. [12] Therefore, it is essential to find natural bioactive substances that have visible antibacterial effects and are environmentally friendly.…”

“…Studies also reported that biological control shows evident resistance to diseases. However, the more severe problems caused by the use of pesticides are plant resistance, pesticide residues, and environmental pollution [11] . The most considerable disadvantage of biological control is that it is slow, unstable, and unable to cope with the sudden increases in diseases [12] .…”

Antibacterial activity of essential oils extracted from the unique Chinese spices cassia bark, bay fruits and cloves

“…Many minimally processed foods are added with preservatives to extend their shelf lives, but consumers have questioned the safety of chemical additives and demanded for the removal of chemical additives from foods (Masri et al, 2021). This has resulted in an increasing interest in searching for preservatives from natural sources that can be used in foods to improve quality and safety (Calvo et Vibrio parahaemolyticus is a Gram-negative bacterium which causes acute gastroenteritis in humans consuming contaminated seafoods (Yang et al, 2019).…”