http://thecoinfront.com/chinese-bitcoin-miner-catches-leukemia-was-his-miner-to-blame/
That article is worthless sensationalism. The basic logic there is that a guy got leukemia and he owns a miner, therefore the miner must have caused his leukemia. By that logic, I got a cold and I own a miner, so my miner must have given me a cold. There's no substance whatsoever there. How many rig owners haven't gotten leukemia?
Aside from that, ASICs certainly do give off some electromagnetic (EM) radiation because any electric current flow generates an EM field. But it's low-power, localized, and non-ionizing. Not to mention that most if not all of it is likely blocked by the metal casing the chips are likely in. The radiation from your cell phone is much more dangerous than anything emitted by an ASIC.