If you care about reducing the arsenic content of rice, here’s my family’s recipe. This method is slower and makes lower quality rice – it’s probably not worth it for most adults. Requires a rice cooker.
Inspired by the Institute for Sustainable Food, which cites this article as its source.
Put the parboiling water in a large pot and bring it to a boil.
While the parboiling water is coming to a boil, wash the rice. Combine the dry rice with enough cool water to cover it. Swirl it around, then pour off the foggy water. Repeat until the water is mostly clear - probably about half a dozen times.
When the parboiling water comes to a boil, set a five minute timer, then immediately add the washed rice to the boiling water. Stir it briefly to prevent it sticking to the bottom of the pot.
When the timer goes off, pour off most of the hot water. Add cold water and swirl, then pour off the water again. Repeat until the water is mostly clear and is cool to the touch.
Pour off basically all of the water. Not actually all of it, but really try to get as much as you can without losing any rice. Aim to leave about a tablespoon for every cup of dry rice you started with.
Put the parboiled rice and remaining water in the rice cooker. Run the rice cooker as normal.