From Envirowiki

Industry is the totality of creative enterprises that humans undertake, including manufacturing, primary industries such as mining, and services.

Prior to specialisation brought about by the agricultural revolutions, and then the industrial revolution, most industrial activity was done directly in the community where it's products were being used. Especially since the industrial revolution, specialisation and faster transport has meant that various parts of industry have moved away from the community (or the community has moved away for industry).

This has the effect that the impact of the by-products of industry, which in the last century or so have become increasingly toxic, are not felt by the community who are using the products. Hence, industry has become increasingly able to get away with more toxic chemicals, since they can just be pumped into someone else's backyard (including pristine ecosystems)

Industry is the biggest emitter of greenhouse gasses, although it can be argued that the people demanding the products of industry are to ultimately to blame - a decrease in consumption of stuff with toxic by-products would have the fairly immediate effect of decreasing the manufacturing of those products.