### process | breath:

Inhalation
* Can cause headaches and dizziness, convulsions and unconsciousness.
* Causes respiratory tract irritation.
* Get medical attention if irritation or discomfort develops.
* Most inhalation affects perceptions
  - increases membrane permeability
  - is part of hyperventilations
  - produces sound
* Remove too fresh air and administer oxygen if person has difficulty breathing.
* Some inhalation causes diseases
  - lung diseases
  - involves ingestion
* appears to be the most significant route of human exposure.
* avoids the digestive tract, which destroys many medications.
* can cause brain and speech damage, as well as liver, heart and renal problems
  - bronchitis or pulmonary edema
  - chronic respiratory irritation
  - coughing, sneezing, nausea, headache and weakness
  - death
  - erosion of the respiratory tract
  - fatal respiratory damage
  - headache and nausea
  - increased respiration followed by depression and convulsions
* can cause irritation of nasal and respiratory passages
  - the nose and throat
  - nose, throat, and respiratory tract irritation, coughing and headache
  - temporary irritation of the eyes and upper respiratory tract
  - upper respiratory irritation
  - help productive coughs by reducing phlegm viscosity
  - inflame the lungs and cause coughing, shortness of breath, and fluid accumulation
  - irritate the upper respiratory system
  - lead to death by asphyxiation
  - result in respiratory irritation or in pulmonary or systemic effects
* causes irritation of mucous membranes
* causes irritation to respiratory passages
  - opportunistic infections in immune deficient people
  - severe lung injury, the full effects appearing several hours after exposure
* direct route into the human body.
* energizes the olfactory nerves which in turn stimulates the limbic system.
* happens when the rib cage opens up and the diaphragm flattens and moves downward.
* has effects.
* irritates nose and throat.
* is aided by use of external intercostals , scalenes and sternocleidomastoid muscles
  - essential for nicotine absorption from a cigarette
  - faster absorption than oral or dermal
  - more of a problem than ingestion
  - one of the most common ways for allergens to enter the body
* is part of breathing
  - the major source of plutonium exposure
* is the most common form of ingestion among humans
  - source of occupational lead exposure
* is the most important route of absorption for many volatile substances
  - exposure in the workplace
* is the other major route for molecules of an active substance to enter the blood stream
  - potentially hazardous route of exposure to depleted uranium dust
  - passive stage of negative pressure breathing
  - process of breathing air through the mouth and nose into our lungs
  - quickest and most direct route to the circulatory system
  - simplest form of diffusion
  - therefore the most direct route between our brains and the outside world
* leads to disease
  - irreversible lung damage
  - pulmonary edema, in which fluid floods the lungs, causing suffocation
* natural, unconscious state.
* occurs by suction as the lungs are expanded by contraction of inspiratory muscles
  - when the diaphragm contracts
* passes through windpipes.
* poses a risk of cancer because of possible asbestos contamination.
* produces damaging effects on the mucous membranes and upper respiratory tract
  - gurgle sound
* provides life force nourishment and lung expansion, while exhalation removes toxins.
* reduces anxiety.
* represents by far the most significant route of entry for hydrogen sulphide.
+ Butane, Dangers: Fuel
  * Butane is dangerous. Inhalation can lead to death by asphyxiation. Contact with the skin can lead to frostbite. If the liquid comes in contact with the air, it will explode.