There are easy, good ways to clean brass without using a synthetic commercial cleaner that may have toxic ingredients.
Most commonly used kitchen cupboard or refrigerator ingredients that contain a natural acid, such as vinegar, Tobasco Sauce, ketchup, tomatoes, milk, and Lemon or Lime juice, will remove tarnish. The tarnish washes away with an acid rub or soak.
You might have to remove the lacquer cover if the brass is new. Do this by submerging the brass in boiling water with a few teaspoons each baking soda and washing soda (available in the laundry section of the supermarket). Once the lacquer has peeled off, polish dry.