The sun beats soap for smelly plastic.

The fix is a combo: a baking soda paste overnight, then direct sunlight. Soap alone never works because the smell isn’t on the surface — it’s trapped inside the plastic.

Plastic is porous. Fish and onion release sulfur compounds that sink into the microscopic pores, and regular washing can’t reach them. That’s why the box smells fine when you wash it and then hits you in the face at lunch the next day.

Here’s the routine: wash it normally, then slather the inside with a thick paste of baking soda and water. Leave it overnight, rinse it out, then put the box in direct sun for a few hours. UV light breaks down those odor molecules. Crumpled newspaper stuffed inside overnight also pulls residual smell out.

A vinegar soak works for milder cases. But if it still stinks after the baking soda and sunlight treatment, the plastic is cheap or scratched, and it’s not worth fighting. Toss it.

And next time, switch to glass. This is a fight you only have to lose once.