Arsenic is very toxic to humans. Arsenic is extremely harmful since it has no taste or odor, so you might be exposed to it without knowing it. In fact, according to the Environmental Protection Agency, approximately half of all people in countries where water is treated with arsenic will consume some amount of it through their drinking water. The other half may get exposure to arsenic in another way, such as by eating food that has been contaminated by arsenic or by inhaling it when it is released into the air. It's hard to know how much arsenic to eat each day. The only way to be sure not to consume any arsenic is not to drink the water or eat the foods that contain it. However, since most people worldwide rely on public water supplies that may contain arsenic, this is not a safe option for many people. Instead, they should consider taking measures to avoid consuming arsenic by itself or in combination with other substances. For example, if you live in an area where heavy metal contamination is a concern, then it makes sense to avoid eating fish because mercury is found in fish. Or, if you are concerned about ingesting chemicals from pesticides, then it would make sense to avoid eating fruits and vegetables that have been grown using chemical-based fertilizers and pesticides.