Biomaterial Database

Maternal exposure to nitrate from drinking water and diet and risk for neural tube defects. 2001

L A Croen, and K Todoroff, and G M Shaw

March of Dimes Birth Defects Foundation, California Department of Health Services, California Birth Defects Monitoring Program, Emeryville, USA. lac@dor.kaiser.org

In this population-based case-control study conducted in California between June 1989 and May 1991, the authors investigated the association between maternal periconceptional exposure to nitrate from drinking water and diet and risk for neural tube defects. The mothers of 538 cases and 539 nonmalformed controls were interviewed regarding residential history, consumption of tap water at home, and dietary intake during the periconceptional period. Dietary nitrate exposure was not associated with increased risk for neural tube defects. Exposure to nitrate in drinking water at concentrations above the 45 mg/liter maximum contaminant level was associated with increased risk for anencephaly (odds ratio (OR) = 4.0, 95% confidence interval (CI): 1.0, 15.4), but not for spina bifida. Increased risks for anencephaly were observed at nitrate levels below the maximum contaminant level among groundwater drinkers only (OR = 2.1, 95% CI: 1.1,4.1 for 5-15 mg/liter; OR = 2.3, 95% CI: 1.1, 4.5 for 16-35 mg/liter; and OR = 6.9, 95% CI: 1.9, 24.9 for 36-67 mg/liter compared with <5 mg/liter). Adjustment for identified risk factors for anencephaly did not substantially alter these associations, nor did control for maternal dietary nitrate, total vitamin C intake, and quantity of tap water consumed. The lack of an observed elevation in risk for anencephaly in association with exposure to mixed water containing nitrate at levels comparable with the concentration in groundwater may indicate that something other than nitrate accounts for these findings.

UI	MeSH Term	Description	Entries
D009436	Neural Tube Defects	Congenital malformations of the central nervous system and adjacent structures related to defective neural tube closure during the first trimester of pregnancy generally occurring between days 18-29 of gestation. Ectodermal and mesodermal malformations (mainly involving the skull and vertebrae) may occur as a result of defects of neural tube closure. (From Joynt, Clinical Neurology, 1992, Ch55, pp31-41)	Craniorachischisis,Developmental Defects, Neural Tube,Diastematomyelia,Exencephaly,Neurenteric Cyst,Spinal Cord Myelodysplasia,Tethered Cord Syndrome,Acrania,Developmental Neural Tube Defects,Iniencephaly,Neural Tube Developmental Defects,Neuroenteric Cyst,Occult Spinal Dysraphism,Occult Spinal Dysraphism Sequence,Tethered Spinal Cord Syndrome,Acranias,Craniorachischises,Cyst, Neurenteric,Cyst, Neuroenteric,Cysts, Neurenteric,Cysts, Neuroenteric,Defect, Neural Tube,Defects, Neural Tube,Diastematomyelias,Dysraphism, Occult Spinal,Dysraphisms, Occult Spinal,Exencephalies,Iniencephalies,Myelodysplasia, Spinal Cord,Myelodysplasias, Spinal Cord,Neural Tube Defect,Neurenteric Cysts,Neuroenteric Cysts,Occult Spinal Dysraphisms,Spinal Cord Myelodysplasias,Spinal Dysraphism, Occult,Spinal Dysraphisms, Occult,Tethered Cord Syndromes
D009566	Nitrates	Inorganic or organic salts and esters of nitric acid. These compounds contain the NO3- radical.	Nitrate
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D002140	California	State bounded on the east by Nevada and Arizona, on the south by Mexico and the Pacific Ocean on the south and west, and on the north by Oregon.
D004032	Diet	Regular course of eating and drinking adopted by a person or animal.	Diets
D005260	Female		Females
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000293	Adolescent	A person 13 to 18 years of age.	Adolescence,Youth,Adolescents,Adolescents, Female,Adolescents, Male,Teenagers,Teens,Adolescent, Female,Adolescent, Male,Female Adolescent,Female Adolescents,Male Adolescent,Male Adolescents,Teen,Teenager,Youths
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D000757	Anencephaly	A malformation of the nervous system caused by failure of the anterior neuropore to close. Infants are born with intact spinal cords, cerebellums, and brainstems, but lack formation of neural structures above this level. The skull is only partially formed but the eyes are usually normal. This condition may be associated with folate deficiency. Affected infants are only capable of primitive (brain stem) reflexes and usually do not survive for more than two weeks. (From Menkes, Textbook of Child Neurology, 5th ed, p247)	Aprosencephaly,Absence of Brain, Congenital,Anencephalia,Anencephalus,Congenital Absence of Brain,Hemicranial Anencephaly,Incomplete Anencephaly,Partial Anencephaly,Anencephalias,Anencephalies, Partial,Anencephaly, Hemicranial,Anencephaly, Incomplete,Anencephaly, Partial,Aprosencephalies,Brain Congenital Absence,Partial Anencephalies