From the WSJ Blog, a discussion of a study into the impact (known)steroid taking players had on their team mates. Apparently it was good suggesting …

that workers not only learn productive skills from their co-workers, but sometimes those skills may derive from unethical practices. These findings may be relevant to many workplaces where competitive pressures create incentives to adopt unethical means to boost productivity and profits

I haven’t been able to get a copy of the paper but it seems to me that it may not so be a spread of unethical behavior but of a common supplier of unethical substances.