How unhealthy do you think it is to work in an area with a lot of car exhaust?

[NickSM11]

I'm not in an enclosed area, but I work in a place where there's about 5 lanes of constant traffic and I am frequently smelling car exhaust throughout my work shift.

Due to some things that happened in my past, my brain is a little slow. I've been trying to sharpen my brain through physical and mental exercise, nutrition, and faith, and it has been working. I'm just worried now that I've started working in this new environment, that the progress that I made will go away.

It's causing me to worry so much. I would like to leave my job, but since I have social anxiety, I have self-doubt about me being able to hold a job anywhere else.

How bad do you really think this could be? Do you think I could be exaggerating the effects? It doesn't seem to bother my co-workers.