Maternal characteristics associated with the dietary intake of nitrates, nitrites, and nitrosamines in women of child-bearing age: a cross-sectional study.
BACKGROUND
Multiple N-nitroso compounds have been observed in animal studies to be both mutagenic and teratogenic. Human exposure to N-nitroso compounds and their precursors, nitrates and nitrites, can occur through exogenous sources, such as diet, drinking water, occupation, or environmental exposures, and through endogenous exposures resulting from the formation of N-nitroso compounds in the body. Very little information is available on intake of nitrates, nitrites, and nitrosamines and factors related to increased consumption of these compounds.


METHODS
Using survey and dietary intake information from control women (with deliveries of live births without major congenital malformations during 1997-2004) who participated in the National Birth Defects Prevention Study (NBDPS), we examined the relation between various maternal characteristics and intake of nitrates, nitrites, and nitrosamines from dietary sources. Estimated intake of these compounds was obtained from the Willet Food Frequency Questionnaire as adapted for the NBDPS. Multinomial logistic regression models were used to estimate odds ratios and 95% confidence intervals for the consumption of these compounds by self-reported race/ethnicity and other maternal characteristics.


RESULTS
Median intake per day for nitrates, nitrites, total nitrites (nitrites + 5% nitrates), and nitrosamines was estimated at 40.48 mg, 1.53 mg, 3.69 mg, and 0.472 microg respectively. With the lowest quartile of intake as the referent category and controlling for daily caloric intake, factors predicting intake of these compounds included maternal race/ethnicity, education, body mass index, household income, area of residence, folate intake, and percent of daily calories from dietary fat. Non-Hispanic White participants were less likely to consume nitrates, nitrites, and total nitrites per day, but more likely to consume dietary nitrosamines than other participants that participated in the NBDPS. Primary food sources of these compounds also varied by maternal race/ethnicity.


CONCLUSIONS
Results of this study indicate that intake of nitrates, nitrites, and nitrosamines vary considerably by race/ethnicity, education, body mass index, and other characteristics. Further research is needed regarding how consumption of foods high in nitrosamines and N-nitroso precursors might relate to risk of adverse pregnancy outcomes and chronic diseases.
Griesenbeck
John S
JS
Department of Epidemiology and Biostatistics, School of Rural Public Health, Texas A&M Health Science Center, College Station, TX, 77843-1266, USA.
Brender
Jean D
JD
Sharkey
Joseph R
JR
Steck
Michelle D
MD
Huber
John C
JC
Rene
Antonio A
AA
McDonald
Thomas J
TJ
Romitti
Paul A
PA
Canfield
Mark A
MA
Langlois
Peter H
PH
Suarez
Lucina
L
D000328:Adult; D003430:Cross-Sectional Studies; D004032:Diet; D005260:Female; D006306:Health Surveys; D006801:Humans; D009566:Nitrates / Q000008:administration & dosage*; D009573:Nitrites / Q000008:administration & dosage*; D009602:Nitrosamines / Q000008:administration & dosage*; D011247:Pregnancy; D014481:United States; D055815:Young Adult
D009566:Nitrates; D009573:Nitrites; D009602:Nitrosamines