Prince of Wales Hospital on alert over laughing gas
Levels of the painkiller used in childbirth are nothing to laugh about as staff found to have been exposed to 12 times the safety limit
A hospital has stopped using laughing gas as a painkiller for mothers in labour after staff were found to have been exposed to up to 12 times the safety limit.
One obstetrician claimed the high levels present in the air could even cause some women to miscarry.
Tests at the Prince of Wales Hospital confirmed suspicions voiced by staff in its obstetrics and gynaecology department that levels of laughing gas - nitrous oxide - in the labour wards were excessive.
Pronouncing itself "very concerned", the Hospital Authority said the airborne concentration of the gas in all public hospital wards was now being assessed, although no similar problems had been found in any other labour wards.
The Prince of Wales Hospital decided to carry out the tests after staff complained in early June about tiredness and headaches at work.
The results showed that 42 out of 48 staff members were exposed to levels of the gas that exceeded the occupational exposure limit of 50ppm (parts per million of inhaled air) set by the Labour Department. The levels ranged from slightly above the limit to 12 times above the limit.
Medical experts, including Chinese University medical professor Raymond Wong Siu-ming and former Medical Association president Dr Choi Kin downplayed the health risks.
