>A UNITED States nuclear-powered submarine could have leaked radioactive water during a Singapore stop last year.
But, the amount leaked was so little that the potential exposure is 100,000 times less than exposure from natural radiation in a year, said Minister of Defence Teo Chee Hean yesterday.
Speaking in Parliament, Mr Teo said the United States had informed Singapore this month that the USS Houston had been leaking trace amounts of radioactive water since June 2006, news agency AFP reported.
"This suggested that the USS Houston could have been leaking during her port call at Changi Naval Base in September 2006," he said in response to a question in Parliament.
He also said that Singapore had asked the US for information, after reports earlier this month said the USS Houston could have been leaking radioactive water during a port call in Japan in March.
US tests showed that the amount of radioactivity that could have leaked from the submarine during its Singapore stop was too small to pose any risk to public health, Mr Teo said in the AFP report.
"To put things into perspective, the US indicated that this was less than the amount of radioactivity found in a common smoke detector, and would not have any adverse effect on human health, marine life or the environment," he said.
The Government has also conducted its own investigations, which showed public safety had not been affected by the leak at Changi Naval Base, Mr Teo said.
The Ministry of Defence's round-the-clock Integrated Environment Monitoring System (IEMS) at Changi Naval Base, in place since February 2003, did not show any abnormal readings during USS Houston's port call.
The IEMS takes readings of air quality, and water and seabed samples to determine the normal background environmental-radiation level, and to detect whether there has been any abnormal level of radiation which may be of safety concern.
The safety limits are set by Singapore's National Environment Agency's Centre of Radiation Protection and Nuclear Science.
