Prenatal lead exposure and fetal growth: Smaller infants have heightened susceptibility.

TitlePrenatal lead exposure and fetal growth: Smaller infants have heightened susceptibility.
Publication TypeJournal Article
Year of Publication2017
AuthorsRodosthenous RS, Burris HH, Svensson K, Amarasiriwardena CJ, Cantoral A, Schnaas L, Mercado-Garcia A, Coull BA, Wright RO, Tellez-Rojo MM, Baccarelli AA
JournalEnviron Int
Volume99
Pagination228-233
Date Published2017 Feb
ISSN1873-6750
KeywordsAdult, Birth Weight, Environmental Pollutants, Female, Fetal Development, Gestational Age, Humans, Infant, Small for Gestational Age, Lead, Male, Maternal Exposure, Mexico, Pregnancy, Pregnancy Trimester, Second, Prospective Studies, Risk, Young Adult
Abstract

BACKGROUND: As population lead levels decrease, the toxic effects of lead may be distributed to more sensitive populations, such as infants with poor fetal growth.

OBJECTIVES: To determine the association of prenatal lead exposure and fetal growth; and to evaluate whether infants with poor fetal growth are more susceptible to lead toxicity than those with normal fetal growth.

METHODS: We examined the association of second trimester maternal blood lead levels (BLL) with birthweight-for-gestational age (BWGA) z-score in 944 mother-infant participants of the PROGRESS cohort. We determined the association between maternal BLL and BWGA z-score by using both linear and quantile regression. We estimated odds ratios for small-for-gestational age (SGA) infants between maternal BLL quartiles using logistic regression. Maternal age, body mass index, socioeconomic status, parity, household smoking exposure, hemoglobin levels, and infant sex were included as confounders.

RESULTS: While linear regression showed a negative association between maternal BLL and BWGA z-score (β=-0.06 z-score units per log BLL increase; 95% CI: -0.13, 0.003; P=0.06), quantile regression revealed larger magnitudes of this association in the <30th percentiles of BWGA z-score (β range [-0.08, -0.13] z-score units per log BLL increase; all P values<0.05). Mothers in the highest BLL quartile had an odds ratio of 1.62 (95% CI: 0.99-2.65) for having a SGA infant compared to the lowest BLL quartile.

CONCLUSIONS: While both linear and quantile regression showed a negative association between prenatal lead exposure and birthweight, quantile regression revealed that smaller infants may represent a more susceptible subpopulation.

DOI10.1016/j.envint.2016.11.023
Alternate JournalEnviron Int
PubMed ID27923585
PubMed Central IDPMC5285303
Grant ListR01 ES021357 / ES / NIEHS NIH HHS / United States
P30 ES000002 / ES / NIEHS NIH HHS / United States
R01 ES013744 / ES / NIEHS NIH HHS / United States
P30 ES023515 / ES / NIEHS NIH HHS / United States
R01 ES014930 / ES / NIEHS NIH HHS / United States
R01 ES020268 / ES / NIEHS NIH HHS / United States
K23 ES022242 / ES / NIEHS NIH HHS / United States
P30 ES009089 / ES / NIEHS NIH HHS / United States