I'm in CT, I think they still recommend you not eat fish (or limit it to a couple a year) from the Housatonic or Hudson rivers (North of nyc, no one in their right mind would eat anything from the Hudson near the city) because of the decades of GE dumping PCBs into them. Obviously we've made some big mistakes in the past.
So, should we be cognizant of our impacts and try to limit them? Sure, and I think we've gotten better with that. Could we do more? Yes. It really starts with the masses though - I try to buy less plastic crap (or buy less in general), I recycle my cans/metal (very easily recyclable - takes far less energy to remelt them than mine new ore, smelt, etc), I recycle what plastic I can, etc. I compost my food waste. My usual trash volume is about one plastic grocery bag a week of stuff that isn't recyclable/compostable.
And yet I know my effort is pointless. We package everything in plastic - rarely are plastic lids marked for recycling, but a pair of pliers or scissors and they come in those absurd plastic shields (also unmarked with a recycling symbol), etc. And if course the vast majority just don't care - I have a friend who tosses all his beer empties in his condo dumpster, "the homeless guys pick through it" (5¢ deposit here), maybe so but I'm sure a lot don't get picked out, besides the non-recyclable stuff that gets tossed. He tosses used motor oil and paint thinner and who knows what else in there too.
I'm not militant about it, I can only control what I do. But I do know we could do far better, consume less crap ("plastic pumpkins"), recycle more. I'm not gonna be changing the world though. Hell, now we've gone back to shitting in the streets, as if we don't know from history what a bad idea that is healthwise.
Climate change? I dunno, again I think it silly to think we have zero impact, but primary cause? I'm not convinced of that.
