the environmental impact of organic (vs. traditional) farming-- or on pollution more generally...

Farming (organic or otherwise) is complicated in its enviro impact. Organic is probably a net gain, but it's expensive (which introduces other complexities). And to the direct point here, it still pollutes and even, has some (surprising) enviro downsides. (Here's a nice article on the topic.) Beyond that: How did the (refined?) compost get to the farmer? How did the organic veggies get to you? And so on. All of those steps produce pollution.

Keep in mind, too, that we're in a partnership with companies to pollute with us, at least implicitly. When I drive a car, I produce pollutants, damage the roads, etc. But I also, in essence, asked Toyota to pollute the environment to produce a car for me. When I eat a steak and drink wine, I asked a rancher and a winemaker to contribute to global warming through cow farts and grape emissions. Electric car owners are creating all sorts of enviro troubles with their batteries. And so on.