Respiratory physiology definition

A disease or illness is nontraumatic physiological harm or loss of capacity produced by systemic, continued, or repeated stress or strain exposure to toxins, poisons, fumes, and so on or other continued and repeated exposures to conditions of the environment over a long period of time. For practical purposes, an occupational illness or disease is any reported condition that does not meet the definition of injury (from a mishap). Illness includes both acute and chronic illnesses, such as, but not limited to, a skin disease, respiratory disorder, or poisoning. 

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