First of all it all depends on your definition of what passively participating is, it could be watching your friends beat up someone of a different race and doing nothing to stop it or something less like knowing a person is being discriminated against for one reason or another and not doing anything about just for the simple reason of it not being your business.
IMO if you are not doing anything directly or intended then you are not perpetuating racism. Another good question is whether by not actively trying to stop it are you perpetuating an unequeal society, and in my personal opinion it doesn't matter whether you are or not, now I am not saying that you should or shouldn't, I just think that no one should think that is a personal responsibility to crusade against anything, they should just want to.
To me what it means to be a racist is being a person whose belief system is directly affected by ethnicity, and what I mean by this is that the way you judge the importance of people or events is based on what color the person or people's that it is pertaining to's skin color was, and if it is an event directly linked to a person or person's of a different race or just a person from a different race then you view it as inferior.
Active racism can be construed as many things from saying a racial slur all the way to assualt or murder perpetrated against a different race. What I would consider passive racism is passing over someone for a job based on skin color rather then qualifacations. You could make a case that Affirmative Action is racist in an indirect way.
Ways you can eliminate racism could be woking with groups that are directed towards equality in society or just learning more about someone's culture and where they are coming from will help you understand the inherent wrongness of racism.
Racism can effect anyone of any race, that is the pure ad simple truth.
