Some technology is inherently dangerous and almost all of it pollutes.
One thing that particularly upsets me, having been a boy during the Fifties who can remember idyllic seaside holidays on sparkling clean beaches, is the tide of faeces and effluents that now filthies our shores. We're such a slob society. If we were a more mature race, we would never countenance the damaging side-effects of otherwise beneficial technologies. But we simply aren't old enough as a civilisation to handle what our scientific curiosity has brought us. So far we've been very lucky.