MCS= Mast Cell Activation Syndrome TILT

Mast cell activation syndrome and mediator release (MCAS) as an underlying mechanism for chemical intolerance.

Mast cells are considered the immune system’s “first responders.” They originate in the bone marrow and migrate to the interface between tissues and the external environment where they then reside. When exposed to “xenobiotics,” foreign substances like chemicals and viruses, they can release thousands of inflammatory molecules called mediators. This response results in allergic-like reactions, some very severe.

These cells can be sensitized by a single acute exposure to xenobiotics such as pesticides or solvents, or by repeated lower-level exposures, such as breathing volatile organic compounds (VOCs) associated with remodeling or new construction. Thereafter, even low levels of those and other unrelated substances can cause the mast cells to release the mediators that can lead to inflammation and illness.