Nitrates can be found in a variety of foods, both prepared and fresh. Small quantities are generally considered safe for human consumption, but larger quantities are known to be dangerous and associated with a number of serious health problems.
The greatest use of nitrates is for fertilizer, according to the U.S. Environmental Protection Agency (EPA). Nitrates are also used in fumigatus to kill rodents and in processed foods as a preservative.
Nitrates like sodium nitrate are commonly used as a preservative in foods like lunch meats, hot dogs, and cured meats. These preservatives help to limit the growth of harmful bacteria. A maximum of 2.75 ounces of nitrates are allowed to be added to 100 pounds of meat.
According to Mayo Clinic, sodium nitrate increases the risk of heart disease. Sodium nitrate is thought to damage blood vessels and cause arteries to harden and narrow. Nitrates may also increase the likelihood of developing diabetes since they affect the way the body processes sugar.
Nitrates can also cause problems with oxygen circulation and increase the risk of certain cancers, according to LIVESTRONG. Problems with oxygen circulation can occur when nitrates bind to red blood cells in the body limiting the ability of the cells to carry oxygen. Nitrates have also been associated with an increased risk of brain tumors, leukemia, and nose and throat tumors.
Nitrates can also be found in drinking water. The most common causes of nitrates in water are fertilizer runoff, sewage or septic tank leaks, and erosion from natural nitrate deposits, according to the EPA.
Infants who drink water contaminated with nitrates can become ill and could even die, according to the EPA. Shortness of breath and blue baby syndrome are among the symptoms that infants may experience.
Municipal water systems are required to test regularly for the presence of nitrates and other contaminants under the Safe Drinking Water Act. Current EPA guidelines for nitrates in water are 10 mg/L or 10 ppm. States may set more restrictive requirements on nitrate contamination.
Private wells may not be regularly tested for nitrates unless the property owner chooses to perform the tests. Local health departments may be able to provide information on water testing options for homeowners with private wells.
Nitrates in water can be effectively reduced using several techniques, including ion exchange, reverse osmosis, and electrodialysis.
Though there is some debate as to how much is too much when it comes to nitrates, there is consensus among health professionals that limiting processed foods like lunch meats and bacon is essential.