1、814Research|Childrens HealthIn 1980,the six New England states discov-ered that PCE(perchloroethylene,tetra-chloroethylene)was leaching into drinkingwater from the inner vinyl lining(VL)ofasbestos cement(AC)water distributionpipes.The vinyl liner,which was introducedin the late 1960s to solve taste
2、and odor prob-lems,had been painted onto the inner surfaceof the pipe in a slurry of PCE and vinyltoluene resin(Piccotex;Johns-ManvilleCorporation,Denver,CO).After drying for48 hr,the pipes were shipped for installation(Demond 1982).Because PCE is a volatilesolvent,it was assumed that most wouldevap
3、orate by the time of pipe installation.However,more than a decade elapsed beforeit was discovered that large quantities of PCEremained in the liner and were slowly leach-ing into the public drinking-water supplies.A substantial number of VL/AC pipeswere installed in the Cape Cod region ofMasssachuse
4、tts(Larsen et al.1983).Becausethe lined pipe was used to replace existingpipe and to extend the water system,contam-ination occurred in an irregular pattern.PCElevels in residential areas of Cape Cod rangedfrom undetectable to 80 g/L along mainstreets and from 1,600 to 7,750 g/L ondead-end streets(D
5、emond 1982).Because itwas prohibitively expensive to replace theVL/AC pipes,a regular schedule of flushingand bleeding was instituted in the most prob-lematic areas to reduce levels to below40 g/L,the suggested no response level in1980(Demond 1982).The current maxi-mum contaminant level is 5 g/L.Ani
6、mal experiments suggest an adverseeffect of prenatal exposure to PCE and theclosely related solvent trichloroethylene(TCE)on offspring weight and growth inseveral species(e.g.,Elovaara et al.1979).However,epidemiologic studies have hadinconsistent results(e.g.,Bove et al.1995;Lagakos et al.1986).We
7、undertook thisstudy to determine the impact of PCE-contaminated drinking water on birth weightand gestational duration using a population-based cohort of Cape Cod children.Materials and MethodsSelection of study population.Children wereeligible for the study if they were born19691983 and their mothe
8、r was living in aCape Cod town with some VL/AC water dis-tribution pipes at the time of their birth.Children were identified by cross-matching thematernal address on the birth certificate withdata collected from water companies on thelocation,installation year,and diameter of allVL/AC water pipes in
9、 the Cape Cod region.Two groups were selected:a)childrenwhose mothers were exposed to PCE-conta-minated drinking water before birth,and b)children whose mothers were unexposedbefore birth.A total of 1,910 children wereinitially designated as“exposed”based on avisual inspection of pipe distribution m
10、aps inthe immediate vicinity of the maternaladdress.The initial exposed group included1,862 singleton births and 24 sets of twins.A comparison group initially designated“unexposed”was randomly selected from theremaining resident births.Unexposed childrenwere frequency matched to exposed childrenon m
11、onth and year of birth.The unexposedgroup of 1,928 children included 1,853 sin-gleton births and 37 sets of twins or triplets.The initial exposure status of a child was con-sidered tentative until survey data on privatewell use became available and more extensiveexposure assessments were completed.W
12、e reviewed birth certificates to obtaininformation on the names of the child andhis parents;the parents ages and educationallevels;the date of the mothers last menstrualperiod;and the childs birth weight andgestational age.The study complied with all applicablerequirements of U.S.regulations governi
13、ng theuse of human subjects in research.The studywas approved by the institutional review boardsof the Massachusetts Department of PublicHealth and Boston University Medical Center,and by the 24A/B/11B Review Committee atthe Massachusetts Department of PublicAddress correspondence to A.Aschengrau,De
14、partmentof Epidemiology,Boston University School of PublicHealth,715 Albany St.,Boston,MA 02118 USA.Telephone:(617)638-5228.Fax:(617)638-4458.E-mail:aaschenbu.eduThis work was supported by grant 5 P42 ES007381from the National Institute of Environmental HealthSciences(NIEHS),National Institutes of H
15、ealth(NIH).Its contents are solely the responsibility of theauthors and do not necessarily represent the officialviews of NIEHS,NIH.D.O.has testified in personal injury cases involv-ing exposure to tetrachloroethylene and trichloro-ethylene.No such litigation is currently pending.The other authors d
16、eclare they have no competingfinancial interests.Received 27 April 2007;accepted 4 February 2008.Prenatal Exposure to Tetrachloroethylene-Contaminated Drinking Water andthe Risk of Adverse Birth OutcomesAnn Aschengrau,1 Janice Weinberg,2Sarah Rogers,1Lisa Gallagher,3Michael Winter,4Veronica Vieira,3Thomas Webster,3and David Ozonoff31Department of Epidemiology,2Department of Biostatistics,3Department of Environmental Health,and 4Data Coordinating Center,Boston University School of Public Health,B
