Dangerous Years

For years researchers have attempted to show that television is dangerous to children.

多年来，研究人员一直试图证明电视对儿童的危害。

Much of this remains dangerous for thousands of years, and a proportion of it can be used to produce weapons-grade plutonium.

废弃物的放射性危险会延续数千年，而且部分还可以用来生产武器级放射性元素钚。

Cesium-137, with a half-life of 30 years, is another dangerous substance emitted in a full-scale nuclear meltdown.

核反应堆完全熔解后，会释放出另一种危险物质铯- 137。铯- 137的半衰期为30年。