His behavior was not constrained by a bystander effect. Since nobody else was working in the lab at the time, Eddie did not have the ability to think that "someone else will take care of this for me," so he had to take action himself as a way of getting the problem rectified. If the bystander effect was in place, it would be more likely that nobody in the lab would have reported the strange smell because everyone would have figured on someone else taking the lead.
