Other historic European capitals such as Rome and London do not have rules for outdoor lead dust levels.

罗马和伦敦等其他欧洲历史名城没有室外铅尘含量的规定。

She said lead dust particles can be so fine that people don’t even know they’re being exposed.

她说，铅尘颗粒非常细小， 人们甚至都不知道自己暴露在铅尘中。