Liquid oxygen has a pale blue colour and is a cryogenic liquid. Cryogenic liquids are liquefied gases that have a normal boiling point below -238 degrees Fahrenheit (-150 degrees Celsius). 

Hazards of Liquid Oxygen: 

• Contact with liquid oxygen can cause severe skin and eye irritation and burns as well as frostbite. 
• Similarly, Inhalation of 80 per cent oxygen at one atmospheric pressure for more than 12 hours can cause irritation of the respiratory tract, nausea, dizziness, vision loss, coughing, chest pain etc. 
• A characteristic neurological syndrome can be observed when pure oxygen is inhaled at pressures greater than two or three atmospheres. 
• Characteristic epilepsy-like convulsions, which may be preceded by visual disturbances such as loss of peripheral vision, also occur. Continued exposure can cause severe convulsions, leading to death. 
• Some common materials like asphalt, kerosene, cloth, wood, paint, tar and dirt containing oil or grease can react violently with liquid oxygen at certain pressures and temperatures 

But these effects are reversible after reduction of oxygen pressure. 

Source:  Down to Earth