In our lives many things we are used to using "possibly" shouldn't have been made due to long term problems>

IMHO plastic bottles are something that could have done without and the world would be a better place if they were invented. 

It's another case of the law of unintended consequences. I'm sure the people who invented the plastic bottle never thought it was gonna grow to the scale it has. That's why I think we must change technologies from time to time. My rule of thumb is: Never do the same thing for 200'000 years. Neanderthals could afford it. We can't.  

In a similar vein, a host of organohalogens such as perfluorinated compounds, are not really biodegradable and have been seen to accumulate in humans and wildlife all over the world (including the arctic).  

But ... they seemed like a good idea at the time.