my job makes me nervous

i am a nail tech so i am around those horrible fumes all day & i do wear a mask when i use the nail polish & etc . but wouldn't it be just as bad to be breathing in the air i just exhaled ? & i can't quit my job i make great money & im in the process of moving into my new apartment . one of my co workers was pregnant and never wore a mask and her baby was perfectly fine but i still worry because everyone is different