Common everyday things that shouldn't been made

[Moontanman]

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. 

[joigus]

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.  

[CharonY]

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).  

[MigL]

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