Hydrogen sulphide, on the other hand - the same poisonous gas produced by rotten eggs - also blocks oxygen but has a looser grip on haemoglobin and thus is easier to remoe, making it a better choice.

• 另外，一种类似的有毒气体，硫化氢，可能会是一个更好的选择。硫化氢由腐蚀的鸡蛋生成的，也可以用来阻断氧气，而且跟血红蛋白的结合没有那么紧，这样也就比较容易清除。