If you are worried about it, just don't put every job experience on your resume; only keep the ones that you think would be a benefit. And if that creates some glaring spots in your work timeline leave dates off too. And if asked in an interview for a timeline you can explain a lot of it. But as always, I would recommend you leave out the negative aspects as to why you left (like the racism and such). It is usually a red flag to future employers when you bad mouth previous workplaces -- justified or not.