Relation between cord blood mercury levels and early child development in a World Trade Center cohort.
OBJECTIVE
This study was designed to determine whether prenatal mercury exposure, including potential releases from the World Trade Center (WTC) disaster, adversely affects fetal growth and child development.


METHODS
We determined maternal and umbilical cord blood total mercury of nonsmoking women who delivered at term in lower Manhattan after 11 September 2001, and measured birth outcomes and child development.


RESULTS
Levels of total mercury in cord and maternal blood were not significantly higher for women who resided or worked within 1 or 2 miles of the WTC in the month after 11 September, compared with women who lived and worked farther away. Average cord mercury levels were more than twice maternal levels, and both were elevated in women who reported eating fish/seafood during pregnancy. Regression analyses showed no significant association between (ln) cord or maternal blood total mercury and birth outcomes. Log cord mercury was inversely associated with the Bayley Scales of Infant Development psychomotor score [Psychomotor Development Index (PDI)] at 36 months (b = -4.2, p = 0.007) and with Performance (b = -3.4, p = 0.023), Verbal (b = -2.9, p = 0.023), and Full IQ scores (b = -3.8, p = 0.002) on the Wechsler Preschool and Primary Scale of Intelligence, Revised (WPPSI-R), at 48 months, after controlling for fish/seafood consumption and other confounders. Fish/seafood consumption during pregnancy was significantly associated with a 5.6- to 9.9-point increase in 36-month PDI, and 48-month Verbal and Full IQ scores.


CONCLUSIONS
Blood mercury was not significantly raised in women living or working close to the WTC site in the weeks after 11 September 2001. Higher cord blood mercury was associated with reductions in developmental scores at 36 and 48 months, after adjusting for the positive effects of fish/seafood consumption during pregnancy.
Lederman
Sally Ann
SA
Columbia Center for Children's Environmental Health, Mailman School of Public Health, Columbia University, New York, New York 10032, USA. sal1@columbia.edu
Jones
Robert L
RL
Caldwell
Kathleen L
KL
Rauh
Virginia
V
Sheets
Stephen E
SE
Tang
Deliang
D
Viswanathan
Sheila
S
Becker
Mark
M
Stein
Janet L
JL
Wang
Richard Y
RY
Perera
Frederica P
FP
D002657:Child Development / Q000187:drug effects*; D002675:Child, Preschool; D015331:Cohort Studies; D004785:Environmental Pollutants / Q000097:blood / Q000633:toxicity*; D005260:Female; D005312:Fetal Blood / Q000737:chemistry*; D005843:Geography; D006801:Humans; D007361:Intelligence Tests; D018811:Maternal Exposure; D008628:Mercury / Q000097:blood / Q000633:toxicity*; D009519:New York City; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology; D017747:Seafood; D047851:September 11 Terrorist Attacks
D004785:Environmental Pollutants; D008628:Mercury