Readers reply: is the world getting smellier?

The long-running series in which readers answer other readers’ questions on subjects ranging from trivial flights of fancy to profound scientific and philosophical conceptsWhen you spray perfume, there’s a smell, but then it dissipates. But surely if everyone is spraying perfume, and making other smells, the world must be accumulating smells. Does the world in general have an odour? And is it getting more potent?
Jade Bulteel, ShropshireSend new questions to nq@theguardian.com. Conti