Chlorination disinfection by-products and risk of congenital anomalies in England and Wales
Author(s)
Type
Journal Article
Abstract
B
ACKGROUND
:
Increased risk of various congenital anomalies has been reported to be associated
with trihalomethane (THM) exposure in the water supply.
O
BJECTIVES
:
We conducted a registry-based study to determine the relationship between THM
concentrations and the risk of congenital anomalies in England and Wales.
M
ETHODS
:
We obtained congenital anomaly data from the National Congenital Anomalies System,
regional registries, and the national terminations registry; THM data were obtained from water
companies. Total THM (< 30, 30 to < 60,
≥
60 μg/L), total brominated exposure (< 10, 10 to < 20,
≥
20 μg/L), and bromoform exposure (< 2, 2 to < 4,
≥
4 μg/L) were modeled at the place of resi-
dence for the first trimester of pregnancy. We included 2,605,226 live births, stillbirths, and termi-
nations with 22,828 cases of congenital anomalies. Analyses using fixed- and random-effects models
were performed for broadly defined groups of anomalies (cleft palate/lip, abdominal wall, major
cardiac, neural tube, urinary and respiratory defects), a more restricted set of anomalies with better
ascertainment, and for isolated and multiple anomalies. Data were adjusted for sex, maternal age,
and socioeconomic status.
R
ESULTS
:
We found no statistically significant trends across exposure categories for either the
broadly defined or more restricted sets of anomalies. For the restricted set of anomalies with iso-
lated defects, there were significant (
p
< 0.05) excess risks in the high-exposure categories of total
THMs for ventricular septal defects [odds ratio (OR) = 1.43; 95% confidence interval (CI),
1.00–2.04] and of bromoform for major cardiovascular defects and gastroschisis (OR = 1.18;
95% CI, 1.00–1.39; and OR = 1.38; 95% CI, 1.00–1.92, respectively).
C
ONCLUSION
:
In this large national study we found little evidence for a relationship between THM
concentrations in drinking water and risk of congenital anomalies.
ACKGROUND
:
Increased risk of various congenital anomalies has been reported to be associated
with trihalomethane (THM) exposure in the water supply.
O
BJECTIVES
:
We conducted a registry-based study to determine the relationship between THM
concentrations and the risk of congenital anomalies in England and Wales.
M
ETHODS
:
We obtained congenital anomaly data from the National Congenital Anomalies System,
regional registries, and the national terminations registry; THM data were obtained from water
companies. Total THM (< 30, 30 to < 60,
≥
60 μg/L), total brominated exposure (< 10, 10 to < 20,
≥
20 μg/L), and bromoform exposure (< 2, 2 to < 4,
≥
4 μg/L) were modeled at the place of resi-
dence for the first trimester of pregnancy. We included 2,605,226 live births, stillbirths, and termi-
nations with 22,828 cases of congenital anomalies. Analyses using fixed- and random-effects models
were performed for broadly defined groups of anomalies (cleft palate/lip, abdominal wall, major
cardiac, neural tube, urinary and respiratory defects), a more restricted set of anomalies with better
ascertainment, and for isolated and multiple anomalies. Data were adjusted for sex, maternal age,
and socioeconomic status.
R
ESULTS
:
We found no statistically significant trends across exposure categories for either the
broadly defined or more restricted sets of anomalies. For the restricted set of anomalies with iso-
lated defects, there were significant (
p
< 0.05) excess risks in the high-exposure categories of total
THMs for ventricular septal defects [odds ratio (OR) = 1.43; 95% confidence interval (CI),
1.00–2.04] and of bromoform for major cardiovascular defects and gastroschisis (OR = 1.18;
95% CI, 1.00–1.39; and OR = 1.38; 95% CI, 1.00–1.92, respectively).
C
ONCLUSION
:
In this large national study we found little evidence for a relationship between THM
concentrations in drinking water and risk of congenital anomalies.
Date Issued
2007-11-06
Date Acceptance
2007-11-06
Citation
Environmental Health Perspectives, 2007, 116 (2), pp.216-222
ISSN
0091-6765
Publisher
The National Institute of Environmental Health Sciences (NIEHS)
Start Page
216
End Page
222
Journal / Book Title
Environmental Health Perspectives
Volume
116
Issue
2
Copyright Statement
Reproduced with permission from Environmental Health Perspectives. Publication of EHP lies in the public domain and is therefore without copyright. All text from EHP may be reprinted freely. Photographs or illustrations copyrighted by other commercial organizations or individuals that may not be used without obtaining prior approval from the holder of the copyright.
Sponsor
Commission of the European Communities
Grant Number
FOOD-CT-2006-036224
Subjects
Science & Technology
Life Sciences & Biomedicine
Environmental Sciences
Public, Environmental & Occupational Health
Toxicology
Environmental Sciences & Ecology
ENVIRONMENTAL SCIENCES
PUBLIC, ENVIRONMENTAL & OCCUPATIONAL HEALTH, SCI
chlorination
congenital anomalies
disinfection by-products
trihalomethanes
ADVERSE BIRTH OUTCOMES
PUBLIC WATER-SUPPLIES
DRINKING-WATER
DEFECTS
TRIHALOMETHANE
EXPOSURE
METAANALYSIS
REGIONS
WEIGHT
GROWTH
Congenital Abnormalities
Disinfection
England
Humans
Risk Factors
Wales
11 Medical And Health Sciences
05 Environmental Sciences
Coverage Spatial
USA