Open the windows in the house to circulate the air.
Place small bowls of white vinegar in the kitchen to absorb the roasted onion smell.
Simmer citrus peels on the stove top in a pot of water for 30 minutes. Add enough water to cover the citrus peels completely.
Remove the roasted onion smell from your hands by pouring baking soda or salt over them. Rub your hands together, and then rinse them under warm water.
Set the oven to 350 degrees Fahrenheit. Bake citrus rinds in the oven on a cookie sheet for 30 minutes to an hour to remove the roasted onion smell.
Burn a slice of bread in the toaster to absorb the onion odors. Watch the toaster carefully to prevent fire. The burned toast smell will fill the room temporarily and replace the onion smell.