Nitrates are chemical compounds that contain nitrogen and oxygen, typically represented by the formula NO₃. They are commonly found in fertilizers, which help plants grow by providing essential nutrients. Nitrates can also occur naturally in soil and water, often as a result of organic matter decomposition. In the human body, nitrates can be converted into nitrites, which have various functions, including helping to regulate blood flow. However, excessive nitrate levels in drinking water can pose health risks, particularly for infants, as they can interfere with the blood's ability to carry oxygen, leading to a condition known as methemoglobinemia.