Latest cyanide(HCN) concentration in the Hong Kong Polytechnic University: 28.6 ppm
Source: 香城教育電視 HKG ETV
According to the International Cyanide Management Code, cyanide is acutely toxic to humans. Liquid or gaseous hydrogen cyanide and alkali salts of cyanide can enter the body through inhalation, ingestion or absorption through the eyes and skin. The rate of skin absorption is enhanced when the skin is cut, abraded or moist; inhaled salts of cyanide are readily dissolved and absorbed upon contact with moist mucous membranes.
The LC50 (concentration that is lethal to 50% of the exposed population)for gaseous hydrogen cyanide is 100-300 ppm. Inhalation of cyanide in this range results in death within 10-60 minutes, with death coming more quickly as the concentration increases.
The National Institute for Occupational Safety and Health (NIOSH) has recommended that workplace exposures to hydrogen cyanide not exceed 4.7 ppm as a 10-minute ceiling.
The government did nothing to remove the toxic chemicals released from their weapons in the past five months.












