Answer: Radioactive material falling from the air or carried in rain water or snow, can deposit on the surface of foods like fruits and vegetables or animal feed.

答：从空气中或者通过雨水落下来的放射性物质可以沉积到诸如水果和蔬菜等食物的表面或动物饲料中。

youdao

Many parents were worried about exposing children to "radioactive rain."

很多家长担心孩子淋到含有放射性物质的雨水。

youdao

Radioactive particles travel in the wind and get absorbed into soil with the help of rain and snow.

放射性颗粒随风飘散，在雨雪的作用下被土壤吸收。

youdao

Radioactive particles travel in the wind and get absorbed into soil with the help of rain and snow.

VOA: special.2011.03.29

Airborne contamination continues to cross the western states, the new data shows, and Boise has seen the highest concentrations of radioactive isotopes in rain so far.

FORBES: Radiation Detected In Drinking Water In 13 More US Cities, Cesium-137 In Vermont Milk

But the Korea Institute of Nuclear Safety said that although small levels of radioactive iodine and caesium particles had been found in rain falling in part of the country, they were not enough to cause concern over public health.

BBC: Japan quake: Nitrogen pumped into nuclear reactor

Radioactive isotopes accumulate in milk after they spread through the atmosphere, fall to earth in rain or dust, and settle on vegetation, where they are ingested by grazing cattle.

FORBES: Radiation Detected In Drinking Water In 13 More US Cities, Cesium-137 In Vermont Milk