By contrast, Liu's method generates nothing more than a mildly alkali metal salt that is easily disposed of. It is also reportedly more efficient than cyanide leaching, an important consideration if the method is to win over industry.
Safety and Environmental Issues
Yes we are talking about the same chemical that is well-known as a deadly toxin in both its solid and gaseous form. With that being said, it must be noted that the cyanide content in the extraction solution is kept at an extremely low level (100 to 500 parts per million); this is done for safety, environmental and economic reasons.
The mining industry takes great care when handling the sodium cyanide solution and there has not been a cyanide related death to a mine employee in over 100 years in North America and Australia.