So, " lead" is a kind of poisonous metal; and " lead" means to be in charge.

所以，“铅” 是一种有毒金属； “领导” 是负责的意思。

Waelz slag, to give its technical name, is composed mainly of silica but is also undesirably rich in poisonous metals like lead and zinc.

学名是威尔兹的废渣主要由硅土组成，也不可避免的含有诸如铅和锌之类的有毒金属。

Or there's the suffering caused by raw sewage in the water supply or poisonous heavy metals that get into the soil via industrial waste.

或是水源中出现的未经处理污水或通过工业废料不规范排放进入土壤层造成健康危害的有毒重金属。