Net transfer abroad of China's solar water heater has been out of cancer

Recently, network Wen said that China's 99% of the solar water heater failed, after repeated heating of water will produce nitrite and other long-term use on health risks or even cause cancer; and proposed, only the advanced foreign closed solar water heater, rather than the more common use in our open water heater vacuum tube solar water heater that is. These claims are based on it? ...Net transfer abroad of China's solar water heater has been out of cancer