The industrial revolution was driven by steam machines. These produce steam in turbulent flow. Which resulted in the production of helium and oxygen gases. When the emission of gamma wave radiation: steam engines do molecular nuclear fusion.
They turn regular water into helium and oxygen gases. So the two hydrogen is become one helium: that is nuclear fusion! Which is usually accompanied by the emission of nuclear radiation. All life on earth in its nuclear radiation, as all life on earth does molecular nuclear fusion, in plant photoblasts or animal and bacterial mitochondria. As you asked.
So nature has no trouble at all doing nuclear fusion from water! Mankind only learned how to with the development of steam engine’s as industrial revolution happened.
We get the formation of inept helium, and breathable oxygen-though we do tend to produce ozone gas! And the gamma wave radiation is very low powered, so doesn’t penetrate even scheme. No toxic end product after all.
Rain does it! Molecular nuclear fusion is totally free and nontoxic. And very exothermic!