If pollutants are the primary driver of adverse mental health outcomes, I’d expect to see Beijing be a never ending parade of people jumping from buildings. Given that’s not the case, I wonder if there is a maximum effect of pollution, or if it just happens to be a correlation

Cars cause a lot of adverse effects. I live right near a road that is entirely too fast. It has a direct effect on my mental health in that it means I can’t open my window due to noise. I can’t easily walk anywhere because half the places I could walk are cut off by a fast and busy road. Anecdotally I’d feel like noise and loss of mobility from nearby roads would have a more substantial effect on mental health, and it doesn’t seem like the study did anything to isolate the different variables caused by cars