Using the train sounds good. But if it is too much time-consuming you could also share your car with your colleagues to get to work. Less Co2 emissions and Money saving at the same time! Also, electric cars are finally out now, I think it is a good purchase! To make every day commuting easy and produce significantly low-levels of Co2.
We could also think about plastic use; stop buying it and reuse the ones that are already with us.