Supporting references and summaries are provided in the TEACH database at http://www.epa.gov/teach/.

Last revised 5/22/07: includes research articles and other information through 2006.

Page 1

Nitrates and Nitrites

TEACH Chemical Summary 

U.S. EPA, Toxicity and Exposure Assessment for Children’s Health

This TEACH Chemical Summary is a compilation of information derived primarily from U.S. EPA and ATSDR resources, 

and the TEACH Database. The TEACH Database contains summaries of research studies pertaining to developmental 

exposure and/or health effects for each chemical or chemical group. TEACH does not perform any evaluation of the validity 

or quality of these research studies. Research studies that are specific for adults are not included in the TEACH Database, 

and typically are not described in the TEACH Chemical Summary. 

I. INTRODUCTION

Nitrates and nitrites are chemicals used in fertilizers, in rodenticides (to kill rodents), and as food 

preservatives (1-5). Nitrates and nitrites come in various forms, but when dried are typically a white or 

crystalline powder. Nitrate (NO3

-

) and nitrite (NO2

-

) are also naturally-occurring compounds that are a 

metabolic product of microbial digestion of wastes containing nitrogen, for example, animal feces or 

nitrogen-based fertilizers (2, 4). Sodium and potassium nitrates are used as fumigants in canisters, which 

are placed underground in rodent dens and holes, and then ignited to explode and release gases that kill 

the rodents (1, 3). Sodium nitrite is a food additive that is used as a preservative (4, 5). 

Likely exposure pathways for children include ingesting contaminated drinking water, most commonly 

of concern for private wells (4); and foods containing preservatives, particularly cured meats such as hot 

dogs and lunch meats (4-7). Nitrates have also been detected in fruits and vegetables (6, 8-10). 

Exposure to nitrates and nitrites at levels above health-based risk values (see Section VI in this Chemical 

Summary) has been reported to have adverse health effects on infants and children. The health effect of 

most concern to the U.S. EPA for children is the “blue baby syndrome” (methemoglobinemia) seen most 

often in infants exposed to nitrate from drinking water used to make formula (11). Infants of ages 0-3 

months are at highest risk for blue baby syndrome because their normal intestinal flora contribute to the 

generation of methemoglobin; older children and adults can experience this syndrome, but at higher 

concentrations of nitrates (2, 4). The blue baby syndrome is named for the blue coloration of the skin of 

babies who have high nitrate concentrations in their blood. The nitrate binds to hemoglobin (the 

compound which carries oxygen in blood to tissues in the body), and results in chemically-altered 

hemoglobin (methemoglobin) that impairs oxygen delivery to tissues, resulting in the blue color of the 

skin (4, 12). The blue coloration can be seen in the lips, nose, and ears in early stages of blue baby 

syndrome, and extend to peripheral tissues in more severe cases. Reduced oxygenation of the tissues can 

have numerous adverse implications for the child, the most severe of which are coma and death (4). 

Exposure to higher levels of nitrates or nitrites has been associated with increased incidence of cancer in 

adults, and possible increased incidence of brain tumors, leukemia, and nasopharyngeal (nose and 

throat) tumors in children in some studies (8, 9, 11, 13-19) but not others (20-29). The U.S. EPA 

concluded that there was conflicting evidence in the literature as to whether exposures to nitrate or 

nitrites are associated with cancer in adults and in children (1, 2).
Chemical Summary Form, Nitrates (continued) 

Supporting references and summaries are provided in the TEACH database at http://www.epa.gov/teach/.

Last revised 5/22/07: includes research articles and other information through 2006.

Page 2

II. EXPOSURE MEDIA AND POTENTIAL FOR CHILDREN’S EXPOSURE1

Exposure 

Media

Relative 

Potential for 

Children’s 

Exposure2,3 Basis4

Diet Higher Use of nitrate fertilizer on crops can result in higher 

concentrations in some foods. Nitrites and, less often, nitrates 

are used as preservatives in foods such as cured meats, for 

example, bacon and salami. Nitrates have been found in 

vegetables and some baby foods that contain vegetables. 

Groundwater Medium Nitrates and nitrites in fertilizers readily migrate from 

fertilized soil to groundwater.

Drinking Water Medium For many situations, the potential for children’s exposure from 

drinking water is medium to low. The potential can be higher 

when private wells become contaminated with nitrates from 

feed lot and agricultural runoff, and contaminated 

groundwater. Some geographic areas are at higher risk of 

drinking water contamination of private wells with nitrates.

Sediment Lower Nitrates and nitrites are highly water soluble and therefore less 

likely to partition to sediment.

Soil Lower Nitrates and nitrites are not retained in soil and quickly 

partition to any water phase.

Ambient Air Lower Nitrates and nitrites are not volatile and are not generally 

released into the air. Registered users of fumigant canisters 

containing nitrates for killing of rodents follow strict use 

protocols that limit exposure to fumes from its use.

Indoor Air Lower Nitrates and nitrites are not usually released in indoor air. Use 

of nitrite or nitrate inhalants from commercial products in the 

home may be a concern for adolescents.

1 For more information about child-specific exposure factors, please refer to the Child-Specific Exposure Factors 

Handbook (http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=55145). 2 The Relative Potential for Children’s Exposure category reflects a judgment by TEACH Workgroup, U.S. EPA, that 

incorporates potential exposure pathways, frequency of exposure, level of exposure, and current state of knowledge. Sitespecific conditions may vary and influence the relative potential for exposure. For more information on how these 

determinations were made, go to http://www.epa.gov/teach/teachprotocols_chemsumm.html. 3 Childhood represents a lifestage rather than a subpopulation, the distinction being that a subpopulation refers to a 

portion of the population, whereas a lifestage is inclusive of the entire population. 4 Information described in this column was derived from several resources (e.g., 1-5) including studies listed in the 

TEACH Database (http://www.epa.gov/teach).
Chemical Summary Form, Nitrates (continued) 

Supporting references and summaries are provided in the TEACH database at http://www.epa.gov/teach/.

Last revised 5/22/07: includes research articles and other information through 2006.

Page 3

III. TOXICITY SUMMARY5, 6

Reduced oxygenation of hemoglobin (methemoglobinemia) has been reported after exposure to nitrateand nitrite-contaminated drinking water; also called the “blue baby syndrome” because of the cyanotic 

(oxygen-deficient) symptoms that result from the reduced oxygenation of the blood (2, 4). Infants less 

than 4 months old are the most sensitive population for methemoglobinemia following exposure to 

nitrates and nitrites, but it does occur in older age groups (12, 13, 30-33). Severe methemoglobinemia 

can lead to coma or death (2, 4). 

Other health effects following fetal exposure to elevated levels of nitrates in drinking water included 

intrauterine growth retardation (34), increased incidence of Sudden Infant Death Syndrome (SIDS) (35), 

cardiac defects (36), and increased risk of nervous system defects (37-40). 

The U.S. EPA concluded that there was conflicting evidence in the literature as to whether exposures to 

nitrate or nitrites are associated with cancer in adults and in children (1, 2). The types of cancers studied 

included non-Hodgkin’s lymphoma as well as stomach and gastric cancers in adults (11); and brain 

tumors, leukemia, and nasopharyngeal cancers in children (13-18, 20-25, 28, 29). Maternal (during 

pregnancy) or child consumption of nitrite-containing meats may be associated with increased incidence 

of brain tumors in children (for more details, see Human Exposures and Effects section) (13, 15-17). 

A few studies have reported other health effects that are possibly associated with nitrate exposure in 

children, including increased incidence of childhood diabetes (41), recurrent diarrhea (42), and recurrent 

respiratory tract infections (43). Other reported effects of chronic exposure reported in adults include 

frequent urination and spleen hemorrhaging (bleeding) (2, 4). Acute high dose ingestion exposure to 

nitrates can cause abdominal pain, muscle weakness, blood in stools and urine, fainting, and death (4). 

Carcinogenicity Weight-of-Evidence Classification7

: There is no weight-of-evidence classification in 

the U.S. EPA IRIS file available at this time for either nitrates (http://www.epa.gov/iris/subst/0076.htm) 

or nitrites (http://www.epa.gov/iris/subst/0078.htm). The World Health Organization International 

Agency for Research on Cancer (IARC) ranked nitrates and nitrites high on the priority list for 

upcoming review of possible carcinogenicity of ingested nitrates and nitrites 

(http://monographs.iarc.fr/ENG/Meetings/prioritylist.pdf). 

5 Please refer to research article summaries listed in the TEACH Database for details about study design considerations 

(e.g., dose, sample size, exposure measurements). 6 This toxicity summary is likely to include information from workplace or other studies of mature (adult) humans or 

experimental animals if child-specific information is lacking for the chemical of interest. Summaries of articles focusing 

solely on adults are not listed in the TEACH Database because the TEACH Database contains summaries of articles 

pertaining to developing organisms. 7 For recent information pertaining to carcinogen risk assessment during development, consult “Guidelines for 

Carcinogen Risk Assessment and Supplemental Guidance on Risks from Early Life Exposure” at 

http://www.epa.gov/cancerguidelines. 
Chemical Summary Form, Nitrates (continued) 

Supporting references and summaries are provided in the TEACH database at http://www.epa.gov/teach/.

Last revised 5/22/07: includes research articles and other information through 2006.

Page 4

IV. EXPOSURE AND TOXICITY STUDIES FROM THE TEACH DATABASE 

This section provides a brief description of human and animal studies listed in the TEACH Database. These descriptions 

generally include the overall conclusion in each study without evaluation or assessment of scientific merit by TEACH. For 

more details about doses and exposure levels, query the TEACH Database. Any consideration of adverse events should 

include an understanding of the relative exposure on a body weight basis. In many cases, exposure levels in animal studies 

are greater than exposure levels normally encountered by humans.

A. HUMAN EXPOSURE AND EFFECTS

< Nitrate contamination of drinking water is of special concern in agricultural areas (4, 12, 30, 44, 45). 

Nitrate-contaminated drinking water often arises as a result of fertilizers applied to crops, which are 

converted to nitrate in the soil and then seep into groundwater and into private residential wells. Of 

particular concern is proximity of animal feed lots to some groundwater sources of drinking water, 

which may lead to groundwater contamination with nitrates from run-off from these feed lots (3, 6, 

11, 12). 

< Nitrates have been measured in foods, and have been detected in vegetables and preserved meats (6-

8, 10, 13, 46, 47), and baby foods (9, 48, 49). Nitrate and nitrite intakes for children in Estonia were 

estimated from measures of nitrate and nitrite concentrations in meat products (50) and in vegetables 

(10). 

< Nitrates have been detected in breast milk, and concentrations increased with increasing 

consumption of nitrates by the mother (51). Nitrates have also been measured in blood and stools of 

children (46). 

< Nitrite exposure of teens from use of nitrite inhalants (e.g., “poppers” also called amyl nitrate, 

gasoline, shoe polish, halothane, whippets, and spray paints) has been reported in a survey of teens 

(52) (See Considerations for Decision Making). 

< Measurement of methemoglobin concentrations in blood has been used as a biomarker of effect for 

infants and children (43). Some studies found an association between concentrations of 

methemoglobin in blood and nitrate exposure (33, 53), but other studies did not (45, 54). 

< Health effects that were significantly associated with nitrate or nitrite exposure during pregnancy 

include increased incidence of intrauterine growth retardation (34), cardiac defects (36), central 

nervous system defects (37-40), Sudden Infant Death Syndrome (SIDS) (35), and miscarriage (55). 

< The most sensitive health effect endpoint for nitrate exposure is methemoglobinemia in infants, also 

called “blue baby syndrome”. When humans metabolize nitrate, an alternative form of hemoglobin, 

called methemoglobin, is formed and is detectable in blood. Infants with blue baby syndrome turn 

blue because their red blood cells, which contain methemoglobin, have a decreased ability to carry 

oxygen. Blue baby syndrome has been reported following exposure of infants to nitratecontaminated drinking water (12, 30-33). Infants of ages 0-3 months are at higher risk for blue baby 

syndrome because their normal intestinal flora contribute to the generation of methemoglobin; older 

children and adults can experience this syndrome, but at higher concentrations of nitrates (2, 4). 
Chemical Summary Form, Nitrates (continued) 

Supporting references and summaries are provided in the TEACH database at http://www.epa.gov/teach/.

Last revised 5/22/07: includes research articles and other information through 2006.

Page 5

< The U.S. EPA concluded that there was conflicting evidence in the literature as to whether exposures 

to nitrate or nitrites are associated with cancer in adults and in children (1, 2). Exposures to nitrates 

or nitrites during pregnancy, and possible associations with incidence of cancer in children, have 

been studied. Two studies reported that increased risk of brain tumors in children was significantly 

associated with increased maternal consumption of increasing amounts of cured meats (containing 

nitrates and nitrites) during pregnancy (13, 17). 

< Possible associations between childhood nitrate exposure and cancer have been investigated. 

Children living in areas with higher nitrate levels in drinking water had higher levels of some forms 

of chromosomal damage than control children living in areas with lower nitrate levels (56). In some 

studies, increased incidence of childhood brain cancer (13, 15-18) and nasopharyngeal cancer (21) 

correlated with childhood nitrate exposure in the diet or drinking water, though other studies found 

no such correlations for some of the same cancers (20-27). An association between nitrate exposure 

and incidence of childhood leukemias was found in one study (57) but not in two others (28, 29). 

Living in areas with high nitrate levels in drinking water during childhood was associated with a 

higher incidence of testicular cancer (58) or urothelial cancer (a specific cancer of the urogenital 

tract) (23). 

< Effects on other systems in humans have been associated with childhood exposure to nitrates or 

nitrites (41-43, 59-62). Exposure of children to nitrates or nitrites was associated with increased 

incidence of childhood diabetes in one study (41), but not others (59-61). Single studies have 

reported associations between children’s exposure to nitrates or nitrites, and recurrent respiratory 

tract infections (43), increased risk for thyroid disorders during adulthood (59), or recurrent diarrhea 

(42). 

B. EXPERIMENTAL ANIMAL EXPOSURE AND EFFECTS

< Several experimental animal studies of health effects following prenatal exposure to nitrates or 

nitrites have been reported (all studies summarized here involved exposure via maternal ingestion). 

Results of studies of teratogenic effects in offspring following maternal exposure to nitrates or 

nitrites during pregnancy were equivocal. For example, adverse effects were observed in offspring 

following prenatal exposure, including delays in brain development in the hippocampal region (63), 

decreased fetal weight gain (64, 65), increased fetal mortality (64), and delayed acquisition of certain 

behaviors (66). However in other studies, prenatal exposure resulted in no observable teratogenic 

effects following prenatal exposure to nitrate (67, 68) or nitrite (67, 69). 

< Effects of prenatal exposure of mice to nitrites on the hematopoietic (blood cell formation) system 

revealed increased liver hematopoiesis in fetuses in one study (70). The liver is a major organ for 

blood cell development in fetuses. In another study, increased levels of methemoglobin were 

observed in pregnant mothers but not their fetuses following prenatal exposure to nitrite (71). 
Chemical Summary Form, Nitrates (continued) 

Supporting references and summaries are provided in the TEACH database at http://www.epa.gov/teach/.

Last revised 5/22/07: includes research articles and other information through 2006.

Page 6

< Prenatal exposure to mixtures of sodium nitrite with other chemicals may have different effects than 

each chemical alone. For example, sodium nitrite administered together with ethylurea induced 

malformations in fetuses, including eye, brain, kidney, and skeletal defects; such malformations 

were not induced by administration of either chemical alone in this study (72). Increased incidence 

of brain tumors was observed in hamster offspring following concurrent maternal exposure to nitrite 

and ethylurea during pregnancy (73, 74). Nitrite and ethylurea are thought to chemically react in the 

gastrointestinal tract to form the potent carcinogen, ethylnitrosourea (73). Female offspring had a 

higher incidence of tumors than male offspring (74). 

V. CONSIDERATIONS FOR DECISION-MAKERS

This section contains information that may be useful to risk assessors, parents, caregivers, physicians, and other decisionmakers who are interested in reducing the exposure and adverse health effects in children for this particular chemical. 

Information in this section focuses on ways to reduce exposure, assess possible exposure, and, for some chemicals, 

administer treatment. 

< The most likely exposure pathways for children are ingestion of contaminated drinking water and 

ingestion of food containing preservatives, such as cured meats and hot dogs (2, 4, 5). 

< General consumer information on preservatives in food is available from the U.S. FDA (75, 76). 

< Some nitrites in household products have been used as inhalants by adolescents and adults to 

enhance sexual performance, and are commonly called “poppers” (77). Compounds include amyl, 

butyl, isobutyl, and cyclohexyl nitrites, and are often sold in small brown bottles and labeled as 

"video head cleaner," "room odorizer," "leather cleaner," or "liquid aroma" (77). 

< The U.S. EPA Oral Reference Dose (RfD) and the Maximum Contaminant Level (MCL) for 

drinking water (see Toxicity Reference Values in this document) are set to prevent 

methemoglobinemia in infants, the most sensitive health endpoint in children (78). 

< The MCL is 1 mg/L for nitrites and 10 mg/L for nitrates in drinking water. As a potential health 

effect, the U.S. EPA states that, “Infants below the age of six months who drink water containing 

nitrate in excess of the MCL could become seriously ill and, if untreated, may die” (78). The U.S. 

EPA makes the same statement for nitrite in water (78).

< Caregivers may consider an alternate water supply, e.g. bottled water, where nitrate-contaminated 

ground water may be impacting drinking water. 

< The U.S. EPA regulates public water systems, and does not have the authority to regulate private 

drinking water wells that serve fewer than 25 people (79). Some states may have rules to protect 

users of these wells. The U.S. EPA urges owners of private wells to have their well water tested 

annually and more often if someone in the household is pregnant or nursing. The U.S. EPA urges 

owners to test their well water for nitrate concentrations and several other contaminants (80). 

< Nitrates are not filtered out of drinking water using filtration devices that utilize only carbon or 

activated carbon filtration. Nitrates can be filtered from drinking water using ion exchange, reverse 

osmosis, or electrolysis methods (81). 
Chemical Summary Form, Nitrates (continued) 

Supporting references and summaries are provided in the TEACH database at http://www.epa.gov/teach/.

Last revised 5/22/07: includes research articles and other information through 2006.

Page 7

< A Nitrate/Nitrite Toxicity Case Study in Environmental Medicine is available from the U.S. Agency 

for Toxic Substances and Diseases Registry (ATSDR), which provides clinical information for 

physicians on the diagnosis and treatment of nitrate and nitrite toxicity. Details of a case study of a 2 

month-old infant with blue baby syndrome is included (4). 

< Consult the “Child-Specific Exposure Factors Handbook,” EPA-600-P-00-002B, for factors to 

assess children’s drinking water consumption rates (82). An updated External Draft of the 2006 

version of this handbook is available (83). 

VI. TOXICITY REFERENCE VALUES

Oral/Ingestion

U.S. EPA Reference Dose (RfD) for Chronic Oral Exposure: 

 Nitrate, 1.6 mg/kg-day, based on the critical effect of early clinical signs of methemoglobinemia 

in infants (excess of 10%) 0-3 months of age exposed to nitrate in infant formula 

(http://www.epa.gov/iris/subst/0076.htm, I.A.I.) (11). Last agency verification date 8/22/90. 

 Nitrite, 1E-1 (or 0.1) mg/kg-day, based on methemoglobinemia in infants chronically exposed to 

nitrite in drinking water (http://www.epa.gov/iris/subst/0078.htm, I.A.I.) (84). Last agency 

verification date 2/26/86. 

U.S. EPA Drinking Water Advisories (4 kg child): 

 Nitrate, 1 day=10 mg/kg and 10 day=10 mg/kg; 

 Nitrite, 1 day=1 mg/kg and 10 day=1 mg/kg 

(http://www.epa.gov/ost/drinking/standards/dwstandards.pdf, p. 9) (85). Last revised Winter, 

2006. 

U.S. EPA Maximum Contaminant Level (MCL) for Drinking Water: 

Nitrate, 10 mg/L; nitrite, 1 mg/L. 

 Both are based on potential health effects of shortness of breath and blue baby syndrome in 

infants (http://www.epa.gov/safewater/mcl.html#mcls) (86). Last revised 7/02.

U.S. EPA Maximum Contaminant Level Goal (MCLG): 

 Nitrate, 10 mg/L; nitrite, 1 mg/L. 

 Both are based on potential health effects of shortness of breath and blue baby syndrome in 

infants (http://www.epa.gov/safewater/mcl.html#mcls) (86). Last revised 7/02. 
Chemical Summary Form, Nitrates (continued) 

Supporting references and summaries are provided in the TEACH database at http://www.epa.gov/teach/.

Last revised 5/22/07: includes research articles and other information through 2006.

Page 8

VII. U.S. FEDERAL REGULATORY INFORMATION

< The reference value, U.S. EPA Drinking Water Advisory for a 4 kg Child, for both nitrate and nitrite 

were recently revised. The 1-day and 10-day values for nitrate are both 10 mg/kg, and for nitrite are 

both 1 mg/kg (see Toxicity Reference Values). 

< The U.S. EPA regulates drinking water for public water systems and drinking water wells that serve 

at least 25 people (79); information is available for owners of private wells (80). 

< Nitrite and nitrate are listed as number 216 and 219 respectively out of 275 chemicals on the 2005 

Priority List of Hazardous Substances for the Comprehensive Environmental Response, 

Compensation, and Liability Act (CERCLA) section 104 (i), as amended by the Superfund 

Amendments and Reauthorization Act (SARA). This is a list in the order of priority of concern of 

substances most commonly found at sites listed on the National Priorities list (NPL); there are 

currently 275 substances on this list (87). 

< The U.S. EPA requires reporting of quantities of certain chemicals that exceed a defined reportable 

quantity, and that quantity varies for different chemicals. Under the Emergency Planning and 

Community Right-to-Know Act (EPCRA) Section 313 “Toxic Chemicals,” quantities of nitrate 

compounds (water soluble) or sodium nitrite greater than 25,000 pounds manufactured or processed, 

or greater than 10,000 pounds otherwise used, is required; under the Comprehensive Environmental 

Response, Compensation, and Liability Act (CERCLA), reporting releases of sodium nitrite of any 

quantity exceeding 100 pounds is required (88). 

VIII. BACKGROUND ON CHEMICAL

A. CAS Number: Nitrate 14797-55-8; Nitrite 14797-65-0. 

B. Physicochemical Properties: Nearly all nitrate and nitrite salts are soluble in water, and occur as a 

whitish powder when not dissolved in water (5). Go to the National Library of Medicine ChemID Web 

site (http://chem.sis.nlm.nih.gov/chemidplus) and search for nitrate or nitrite. 

C. Production: Fertilizers comprise the majority of environmental releases of inorganic sources of 

nitrates (5). Total U.S. reported releases of nitrate compounds totaled over 291 million pounds in 2005 

(89). 

D. Uses: Primary sources of organic nitrates in the environment include human sewage and livestock 

manure (5). Sources of inorganic nitrates in the environment include potassium nitrate and ammonium 

nitrate, which may leach to ground water and contaminate private residential drinking water wells (3, 5). 

Potassium nitrates are mainly used as fertilizers and may also be used in heat transfer salts, glass and 

ceramics, rodenticides, and in matches and fireworks (2). Ammonium nitrates are mostly used as 

fertilizers, but also in explosives and blasting agents (2). 
Chemical Summary Form, Nitrates (continued) 

Supporting references and summaries are provided in the TEACH database at http://www.epa.gov/teach/.

Last revised 5/22/07: includes research articles and other information through 2006.

Page 9

E. Environmental Fate: Nitrates are very mobile in soil and have a high potential to migrate to ground 

water due to high solubility in water and weak retention by soil (3, 5). Nitrates and nitrites do not 

volatilize and therefore are likely to remain in water until consumed by plants or other organisms (3). 

Ammonium nitrate is taken up by bacteria, and nitrate degradation is fastest under anaerobic conditions 

(5). Nitrite is easily oxidized to nitrate, and nitrate is the more predominant compound of the two 

detected in groundwater (4). 

Additional information on nitrates and nitrites is available in the TEACH Database and at the following 

Web sites:

www.epa.gov/iris/subst/0076.htm 

www.epa.gov/iris/subst/0078.htm 

 www.epa.gov/safewater/dwh/c-ioc/nitrates.html 
Chemical Summary Form, Nitrates (continued) 

Supporting references and summaries are provided in the TEACH database at http://www.epa.gov/teach/.

Last revised 5/22/07: includes research articles and other information through 2006.

Page 10

REFERENCES

1. U.S. Environmental Protection Agency. 1991. "Reregistration Eligibility Decision: Inorganic 

Nitrate/Nitrite (Sodium and Potassium Nitrates)." 

http://www.epa.gov/oppsrrd1/REDs/old_reds/4052red.pdf. 

2. U.S. Environmental Protection Agency Ground Water and Drinking Water. 2006. "Consumer 

Factsheet on: Nitrates/Nitrites." http://www.epa.gov/safewater/dwh/c-ioc/nitrates.html. 

3. U.S. Environmental Protection Agency Pesticides and Toxic Substances. 1991. "R.E.D. Facts: 

Inorganic Nitrates/Nitrite (Sodium and Potassium Nitrates)." 

http://www.epa.gov/oppsrrd1/REDs/factsheets/4052fact.pdf. 

4. U.S. Agency for Toxic Substances and Diseases Registry. 2001. "Case Studies in Environmental 

Medicine: Nitrate/Nitrite Toxicity." 

http://www.atsdr.cdc.gov/HEC/CSEM/nitrate/docs/nitrate_nitrite.pdf. 

5. World Health Organization. 2006. "International Program on Chemical Safety, Environmental Health 

Criteria 5: Nitrates, Nitrites, and N-Nitroso Compounds." 

http://www.inchem.org/documents/pims/chemical/pimg016.htm. 

6. Laitinen, S., et al. 1993. "Calculated dietary intakes of nitrate and nitrite by young Finns." Food 

Addit.Contam 10(4):469-477. 

7. Reinik, M., et al. 2005. "Nitrites, nitrates and N-nitrosoamines in Estonian cured meat products: 

intake by Estonian children and adolescents." Food Addit.Contam 22(11):1098-1105. 

8. Sanchez-Echaniz, J., et al. 2001. "Methemoglobinemia and consumption of vegetables in infants." 

Pediatrics 107(5):1024-1028. 

9. Dusdieker, L.B., et al. 1994. "Nitrate in baby foods. Adding to the nitrate mosaic." 

Arch.Pediatr.Adolesc.Med. 148(5):490-494. 

10. Tamme, T., et al. 2006. "Nitrates and nitrites in vegetables and vegetable-based products and their 

intakes by the Estonian population." Food Addit.Contam 23(4):355-361. 

11. U.S. Environmental Protection Agency. 1991. "Integrated Risk Information System (IRIS): Nitrate." 

http://www.epa.gov/iris/subst/0076.htm. 

12. Knobeloch, L., et al. 2000. "Blue babies and nitrate-contaminated well water." Environ.Health 

Perspect. 108(7):675-678. 

13. Preston-Martin, S., et al. 1996. "Maternal consumption of cured meats and vitamins in relation to 

pediatric brain tumors." Cancer Epidemiol.Biomarkers Prev. 5(8):599-605. 

14. Ward, M.H., et al. 2000. "Dietary exposure to nitrite and nitrosamines and risk of nasopharyngeal 

carcinoma in Taiwan." Int.J.Cancer 86(5):603-609. 

15. Pogoda, J.M., and S. Preston-Martin. 2001. "Maternal cured meat consumption during pregnancy 

and risk of paediatric brain tumour in offspring: potentially harmful levels of intake." Public Health 

Nutr. 4(2):183-189. 

16. Sarasua, S., and D.A. Savitz. 1994. "Cured and broiled meat consumption in relation to childhood 

cancer: Denver, Colorado (United States)." Cancer Causes Control 5(2):141-148. 

17. McCredie, M., et al. 1994. "Antenatal risk factors for malignant brain tumours in New South Wales 

children." Int.J.Cancer 56(1):6-10. 

18. Preston-Martin, S., et al. 1982. "N-Nitroso compounds and childhood brain tumors: a case-control 

study." Cancer Res. 42(12):5240-5245. 

19. Volkmer, B.G., et al. 2005. "Influence of nitrate levels in drinking water on urological malignancies: 

a community-based cohort study." BJU.Int 95(7):972-976. 
Chemical Summary Form, Nitrates (continued) 

Supporting references and summaries are provided in the TEACH database at http://www.epa.gov/teach/.

Last revised 5/22/07: includes research articles and other information through 2006.

Page 11

20. Bunin, G.R., et al. 1994. "Maternal diet and risk of astrocytic glioma in children: a report from the 

Childrens Cancer Group (United States and Canada)." Cancer Causes Control 5(2):177-187. 

21. Bunin, G.R., et al. 1993. "Relation between maternal diet and subsequent primitive neuroectodermal 

brain tumors in young children." N.Engl.J.Med. 19;329(8):536-541. 

22. Mueller, B.A., et al. 2001. "Residential water source and the risk of childhood brain tumors." 

Environ.Health Perspect. 109(6):551-556. 

23. Lubin, F., et al. 2000. "The role of nutritional habits during gestation and child life in pediatric brain 

tumor etiology." Int.J.Cancer 86(1):139-143. 

24. Howe, G.R., et al. 1989. "An exploratory case-control study of brain tumors in children." Cancer 

Res. 49(15):4349-4352. 

25. Kuijten, R.R., et al. 1990. "Gestational and familial risk factors for childhood astrocytoma: results of 

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Page 12

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Page 13

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Chemical Summary Form, Nitrates (continued) 

Supporting references and summaries are provided in the TEACH database at http://www.epa.gov/teach/.

Last revised 5/22/07: includes research articles and other information through 2006.

Page 14

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