我的朋友于老三办了一个选矿厂,因此暴富。一天,路过他的工厂,凑巧遇到他。他热情地邀我进厂聊了一阵。我提出想参观他的工厂,他二话没说,便陪我参观。尽管戴上了口罩和遮尘帽,但走入选矿车间,由于尘埃密布,呼吸困难,还是有一种窒息的感觉。我听说这种矿毒性大,对身体有很大的? My friend did a dressing plant in the third, so rich. One day, passing his factory, happened to meet him. He warmly invited me into the factory to talk for a while. I proposed to visit his factory, and he said no to anything else. Despite wearing masks and dust caps, it was felt suffocated to go into the beneficiation plant because of the dusty and breathing difficulties. I hear this kind of mine is very toxic and very big to the body?