“Natural” does not mean safe
Vinegar ruins marble, soda pits aluminium, and both are perfectly natural. What matters is the chemistry, not the origin story.
1 minute
Household staples are cheap, effective and low-impact, and none of that makes them harmless. Vinegar is an acid: it etches marble, limestone and travertine permanently, and it corrodes rubber seals over time. Soda crystals are alkaline enough to dull aluminium in a single wash and to dry out skin over a long job.
The reverse mistake is just as common. A product is not dangerous because it has a long chemical name — sodium bicarbonate is baking soda, and sodium chloride is table salt.
The pairs that genuinely produce toxic gas are worth knowing by heart, and they involve chlorine bleach: bleach with vinegar or any acid gives chlorine gas, and bleach with ammonia gives chloramine. Both burn eyes and airways. Neither is a rumour.
The useful question is never whether something is natural. It is what the surface is made of, and what the substance does to it.