They were exposed to radioactive fallout during nuclear weapons tests.

他们在核武器试验过程中暴露于放射性核辐射。

《柯林斯英汉双解大词典》

These 85, 000 baby teeth were collected in the late 1950s and early 1960s from children in the st Louis area to study the effects of radioactive fallout in the environment.

这85,000个婴儿的牙齿是在1950年后期和1960年代初期从圣路易斯的孩子们那里采集到的，用来研究一定的环境下放射性坠尘的影响。

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The phenomenon is called radioactive fallout.

这一现象即称之为放射性尘降。

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The biggest hazard of atmospheric tests was that radioactive fallout would get into the human food chain.

CNN: ASIANOW - Asiaweek

The UK charity Chernobyl Children's Life Line helps families in Ukraine and neighbouring Belarus affected by harmful radioactive fallout.

BBC: Inverness and Nairn charities host Chernobyl events

Meanwhile, fears over radioactive fallout here in the United States, which led to panic buying of an anti-radiation medicine and survival gear in the West, have been allayed for the time being by EPA findings that almost no radiation has survived the 5, 000 mile journey across the Pacific Ocean.

FORBES: Radiation Found in Food and Water in Japan [Updated]