This sequence pertains to exposures to chemicals such as cyanide, solvents, pesticides and any other chemical capable of entering the body. At this point, a chemical exposure that appeared to be well tolerated previously is no longer tolerated, and is now encroaching on vital capacity. It is a common observation that individuals who become sensitive to one chemical often begin to react to others. This is because the body has a limited number of detoxification mechanisms. When the mechanism has been damaged, all chemicals that are eliminated through that mechanism will not be well handled and will provoke symptoms.
Individuals vary greatly in their abilities to resist the damaging effects of chemicals.
It is always the individuals with the least capacity to tolerate chemicals who are the first to become sick. Others in the group might tolerate the same chemical exposure indefinitely without apparent illness. Nobody in the world today is free from some degree of chemical body burden. Individual tolerances and exposures may vary greatly, but we are all somewhere on the spectrum between minimal burden and having taken on that last bit of chemical that pushes us over the brink into a state of chronic illness.