This is what humans have been saying about auto exhaust, factory emissions, agricultural emissions etc for a hundred years. It’s turned out wrong in every way.
(edit) Now that I think about it, isn’t your position basically the same as the right wing position on climate change? That even if it exists humans are too small to actually effect the huge atmosphere so it’s not human caused.
“The amount of X that industry is dumping into the Y is insignificant and nothing to be concerned about” is an inherently flawed argument, and all the worse when there are 8 billion people on the planet.