Is Rain Water Safe to Drink?

Not without treatment, according to CDC. It says rainwater is not necessarily safe to drink without first removing germs and chemicals from it, and advises regularly testing your rainwater for germs and chemicals if you drink, cook or bathe with it.

CDC says rainwater can pick up germs and chemicals in the air and as it moves into a collection system, and that dust, smoke and other particles in the air can contaminate it before it lands on the roof. Once it falls, it says chemicals like asbestos, lead or copper can get into the water from roofing materials, gutters, piping, storage materials and other surfaces, and dirt and germs from the roof, such as bird droppings, can wash into a rain barrel or tank. The EPA's rain barrel page similarly says rain flowing over a roof can pick up bacteria from birds and other animals and chemicals from roof materials, factors to consider before using rain barrel water on edible plantings.

CDC suggests using rainwater only in ways that limit the chance you will swallow it, such as watering plants you do not eat or washing items you do not use for cooking or eating. If possible, it recommends tap water from a public system or bottled water instead of rainwater for drinking, cooking, brushing your teeth, rinsing fruits or vegetables and watering plants you plan to eat. If your rainwater contains germs or chemicals, it says to treat it with a method or system that removes those specific germs or chemicals.