Tests for Japanese food imports could be stepped up after Tokyo decided to flush contaminated water from the Fukushima nuclear plant into the sea, food and health chief Sophia Chan Siu-chee said yesterday.

Also under consideration is tighter criteria for food imports from Fukushima and nearby areas, she told lawmakers.

Chan said the SAR has expressed "grave concern" and requested Tokyo provide data and information on control and surveillance, including the method and actual location of the nuclear wastewater discharges, a list of the radionuclides involved and their concentrations, the frequency and volume of discharges and the monitoring programs for wastewater treatment and the surrounding environment.

Japan should not, she said, carry out such discharges unilaterally.

"Depending on the circumstances, we will not rule out increasing tests on Japanese food imports and tightening import controls on food products, including fishery and agricultural products, from Fukushima and its neighboring areas," she added.

China's foreign ministry has urged Japan to handle the issue of nuclear wastewater disposal prudently and responsibly.

Chan said the SAR supports the ministry's stance and relayed its trade concerns to the Office of the Commissioner of the Ministry of Foreign Affairs in Hong Kong.

Currently, Hong Kong does not allow vegetable, fruit, milk, milk beverage and dried milk imports from Fukushima, and radiation certificates are required for imports from four neighboring prefectures.

The Centre for Food Safety has also tested more than 750,000 samples of food imports from Japan since 2011, after the government implemented additional control and surveillance measures. None were found to have exceeded radiation levels, she said.

Chan said it will continue to adopt a risk-based approach in conducting radiation tests on Japanese food products.

Last month, Japan said it will release more than one million tonnes of contaminated water into the sea from the nuclear plant, which was damaged by an earthquake and tsunami in 2011. The first release of water will take place in about two years.

Sophia Chan

Nuke fears may spur stricter tests