In utero exposure to compounds with dioxin-like activity and birth outcomes.
BACKGROUND
Maternal exposure to dioxins and dioxin-like compounds may affect fetal growth and development. We evaluated the association between in utero dioxin-like activity and birth outcomes in a prospective European mother-child study.


METHODS
We measured dioxin-like activity in maternal and cord blood plasma samples collected at delivery using the Dioxin-Responsive Chemically Activated LUciferase eXpression (DR CALUX) bioassay in 967 mother-child pairs, in Denmark, Greece, Norway, Spain, and England. Multiple linear regression models were used to investigate the associations with birth weight, gestational age, and head circumference.


RESULTS
Plasma dioxin-like activity was higher in maternal sample than in cord samples. Birth weight was lower with medium (-58 g [95% confidence interval (CI) = -176 to 62]) and high (-82 g [-216 to 53]) tertiles of exposure (cord blood) compared with the lowest tertile. Gestational age was shorter by approximately half a week in the highest compared with the lowest (-0.4 weeks [95% CI = -0.8 to -0.1]). This association was stronger in boys than in girls, although the statistical evidence for interaction was weak (P = 0.22). Analysis based on CALUX-toxic equivalents expressed per milliliter of plasma showed similar trends. We found no association between dioxin-like activity in maternal plasma and birth outcomes.


CONCLUSIONS
Results from this international general population study suggest an association between low-level prenatal dioxin-like activity and shorter gestational age, particularly in boys, with weaker associations for birth weight.
From the aCentre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain; bMunicipal Institute of Medical Research (IMIM-Hospital del Mar), Barcelona, Spain; cCIBER Epidemiología y SaludPública (CIBERESP), Barcelona, Spain; dParc de Salut Mar, Obstetrics and Gynecology Department, Barcelona, Spain; eNational Institute of Health and Medical Research (INSERM), Team of Environmental Epidemiology Applied to Reproduction and Respiratory Health, Institute Albert Bonniot, Grenoble, France; fBiodetection Systems B.V., Amsterdam, The Netherlands; gDepartment of Social Medicine, Faculty of Medicine, University of Crete, Heraklion, Greece; hCentre for Epidemiology and Biostatistics, Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds, United Kingdom; iBradford Institute for Health Research, Bradford Royal Infirmary, Bradford, United Kingdom; jSection of Environmental Health, Department of Public Health, University of Copenhagen, Copenhagen, Denmark; kFaculty of Health and Life sciences, Pompeu Fabra University, Barcelona, Spain; lDepartment of Pediatrics, Obstetrics and Gynecology and Preventive Medicine, Faculty of Medicine, Autonomous University of Barcelona, Barcelona, Spain; mDepartment of Chemicals and Radiation, Division of Environmental Medicine, Norwegian Institute of Public Health, Oslo, Norway; nDepartment of Food, Water and Cosmetics, Division of Environmental Medicine, Norwegian Institute of Public Health, Oslo, Norway; oDepartment of Cancer Research and Molecular Medicine, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway; pInstitute of Biological Research and Biotechnology, National Hellenic Research Foundation, Athens, Greece; qDepartment of Biosciences and Nutrition, Unit of Molecular Epidemiology, Karolinska Institute, Huddinge, Sweden; rEpidemiology, Biostatistics, and Clinical Trials, IRCCS AOU San Martino-IST-Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy; sDepartme
Marina
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Vafeiadi
Silvia
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Agramunt
Marie
M
Pedersen
Harrie
H
Besselink
Leda
L
Chatzi
Eleni
E
Fthenou
Sarah
S
Fleming
Laura J
LJ
Hardie
John
J
Wright
Lisbeth E
LE
Knudsen
Jeanette K S
JK
Nielsen
Jordi
J
Sunyer
Ramon
R
Carreras
Gunnar
G
Brunborg
Kristine B
KB
Gutzkow
Unni C
UC
Nygaard
Martinus
M
Løvik
Soterios A
SA
Kyrtopoulos
Dan
D
Segerbäck
Domenico F
DF
Merlo
Jos C
JC
Kleinjans
Martine
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Vrijheid
Manolis
M
Kogevinas
D000328:Adult; D001681:Biological Assay; D001724:Birth Weight / Q000187:drug effects*; D004147:Dioxins / Q000097:blood / Q000633:toxicity*; D004785:Environmental Pollutants / Q000097:blood / Q000633:toxicity*; D005060:Europe; D005260:Female; D005312:Fetal Blood / Q000737:chemistry; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D016014:Linear Models; D008297:Male; D018811:Maternal Exposure / Q000009:adverse effects*; D011247:Pregnancy; D047928:Premature Birth / Q000139:chemically induced*; D011446:Prospective Studies; D012737:Sex Factors
D004147:Dioxins; D004785:Environmental Pollutants