you should report this to railway instead of convening such msg. If you think every one should keep the clean environment then this can't be possible. so you should tweet about this issue to railway or can contact at 138 so that the train can get clean ASAP and every feel good about train. may be you know this is human tendency that if we find a garbage place we will through the garbage at that place if or not that is actual garbage place. don't point on some one bad habit think how can you make it better for other then other will make best for you.