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。
2
Monitoring stations in many cities were ordered to conduct around-the-clock surveillance of radioactive substances in the air and sea water.
许多城市的监测站受命对空气和海水中的放射性物质进行全天监测。
3
Radon is a natural radioactive gas that emanates from the ground into the air.