What are the symptoms of methane overexposure?

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High concentrations of this gas can cause an oxygendeficient environment. Individuals breathing such an atmosphere may experience
Symptoms which include
headaches, ringing in ears, dizziness, drowsiness, unconsciousness, nausea, vomiting, and depression of all the senses.

Under some circumstances of overexposure, death may occure.

The effects associated with various level of oxygen are as follows:
OTHER POTENTIAL HEALTH EFFECTS:
Contact with cryogenic liquid or rapidly expanding gases (which are released under high pressure) may cause frosbite. Symptoms of
Frostbite include change in skin color to white or grayish -yellow. The pain after contact with the liquid can quickly subside.
HEALTH EFFECTS OR S RISKS FROM EXPOSURE: An explanation in lay Terms. Overexposure to Methane may cause the following
Health effects:

ACUTE: The most significant hazard associated with this gas is inhalation of oxygen deficiency include respiratory difficulty, headeache,
Dizziness, and nausea. At high concentrations, unconsciousness or death may occur. Contact with cryogenic liquid or rapidly expanding
Gasses may cause frostbite.

CHRONIC: There are currently no know adverse health effects associated with chronic exposure to Methane.

TARGET ORGAN: Respiratory system.