Btw, a side info on my usage.

I noticed that killing spawners also created plumes of pollution, forcing nearby nests to send waves and pushing up evo. I enjoy the depth that it adds that way, so, I have it installed more for adding combat difficulty than what's shown on the tin. I hope it was intended. No change needed here, just wished to let you know.

Cheers!

I'd prefer if this effect was controlled and optional.

Ahh. I disabled pollution for killing biters (which was an instant death spiral) but didn't think to do it for spawners. If I don't get that fixed soon, I'll handle it in my 2.0 update later this year.