I don’t know where you live but the OP talks about London which has the same issue than here in Paris and is probably better than most large city in South East

I don’t know where you live but the OP talks about London which has the same issue than here in Paris and is probably better than most large city in South East Asia. You can drop your pastoral dream of dust and pollen. The pollution is mostly diesel exhaust, industrial fumes and tire residues. That’s extremely unhealthy.