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We report longitudinal serum concentrations of select persistent organic pollutants (POPs) in children at ages 7 and 9 years and in their mothers prenatally and again when the children were 9 years old. The participating families were enrolled in the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS), a longitudinal birth cohort study of low-income Hispanic families residing in the Salinas Valley, California. We observed decreasing concentrations in the mothers with year of serum collection (2009 vs 2011) for six out of seven polybrominated diphenyl ether (PBDE) congeners and for 2,2',4,4',5-pentachlorobiphenyl (CB-99; p < 0.05). The 9-year-old children had similarly decreasing serum concentrations of all seven PBDE congeners, CB-99, and 2,2',3,4,4',5'- and 2,3,3',4,4',6-hexachlorobiphenyl (CB-138/158) with year of serum collection (2009 vs 2011; p < 0.05). In mixed effect models accounting for weight gain as the children aged from 7 to 9 years, we observed an annual decrease (-8.3% to -13.4%) in tri- to hexaBDE concentrations (p < 0.001), except for 2,2',3,4,4'-tetrabromodiphenyl ether (BDE-85) and 2,2',4,4',5,5'-hexabromodiphenyl ether (BDE-153). The concentrations of these congeners were not associated with time of serum collection and instead showed an -0.9% to -2.6% decrease per kilogram of weight gain during the study period (p < 0.05). In the case of tetra- to heptachlorobiphenyls, we observed -0.5% to -0.7% decrease in serum concentration per kilogram of weight gain (p < 0.05) and -3.0% to -3.7% decrease in serum concentration per year of aging (p < 0.05), except for 2,3',4,4',5-pentachlorobiphenyl (CB-118) and 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153), which were not associated with time of serum draw. 2,2-Bis(4-chlorophenyl)-1,1-dichloroethene (p,p'-DDE) decreased -2.4%/kg of weight gain between the two sampling points (p < 0.001). These findings suggest that as children grow, dilution in a larger body size plays an important role in explaining reductions in body burden in the case of traditional POPs such as PCBs and p,p'-DDE. By contrast, in the case of PBDEs, reductions are likely explained by reduction in exposure, as illustrated by decreased concentrations in more recent years, possibly amplified by presumed shorter biological half-life than other POPs.

BACKGROUND: Bisphenol A (BPA) and 4-tertiary-octylphenol (tOP) are industrial chemicals used in the manufacture of polycarbonate plastics and epoxy resins (BPA) and nonionic surfactants (tOP). These products are in widespread [...]

BACKGROUND: Polyfluoroalkyl chemicals (PFCs) have been used since the 1950s in numerous commercial applications. Exposure of the general U.S. population to PFCs is widespread. Since 2002, the manufacturing practices for PFCs in the United States have changed considerably. OBJECTIVES: We aimed to assess exposure to perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA), and eight other PFCs in a representative 2003-2004 sample of the general U.S. population [greater than or equal to]12 years of age and to determine whether serum concentrations have changed since the 1999-2000 National Health and Nutrition Examination Survey (NHANES). METHODS: By using automated solid-phase extraction coupled to isotope dilution-high-performance liquid chromatography-tandem mass spectrometry, we analyzed 2,094 serum samples collected from NHANES 2003-2004 participants. RESULTS: We detected PFOS, PFOA, PFHxS, and PFNA in > 98% of the samples. Concentrations differed by race/ethnicity and sex. Geometric mean concentrations were significantly lower (approximately 32% for PFOS, 25% for PFOA, 10% for PFHxS) and higher (100%, PFNA) than the concentrations reported in NHANES 1999-2000 (p < 0.001). CONCLUSIONS: In the general U.S. population in 2003-2004, PFOS, PFOA, PFHxS, and PFNA serum concentrations were measurable in each demographic population group studied. Geometric mean concentrations of PFOS, PFOA, and PFHxS in 2003-2004 were lower than in 1999-2000. The apparent reductions in concentrations of PFOS, PFOA, and PFHxS most likely are related to discontinuation in 2002 of industrial production by electrochemical fluorination of PFOS and related perfluorooctanesulfonyl fluoride compounds. KEY WORDS: biomonitoring, C8, exposure, PFCs, PFOA, PFOS, prevalence, serum. Environ Health Perspect 115:1596-1602 (2007). doi:10.1289/ehp.10598 available via http://dx.doi.org/ [Online 29 August 2007], Concern about exposure of the ecosystem, including humans, to halogenated persistent organic pollutants (POPs) has existed for several decades. Many of these chemicals are persistent and toxic, tend to bioaccumulate, [...]

Objectives. Although several studies describe the 22q11.2 deletion, population-based data are scant. Such data are needed to evaluate properly the impact, distribution, and clinical presentation of the deletion in the population. Our goals were to assess the population-based birth prevalence of the 22q11.2 deletion and its associated phenotype and its impact on the occurrence of heart defects. Methods. We evaluated data on infants who were born from 1994 through 1999 to women who resided in metropolitan Atlanta. We matched records from the Metropolitan Atlanta Congenital Defects Program (a population-based registry with active case ascertainment), the Sibley Heart Center at Children&apos;s Healthcare of Atlanta, and the Division of Medical Genetics at Emory University. We used birth certificate data for the denominators of the rates. Results. We identified 43 children with laboratory-confirmed 22q11.2 deletion among 255 849 births. The overall prevalence was 1 in 5950 births (95% confidence interval: 1 in 4417 to 1 in 8224 births). The prevalence was between 1 in 6000 and 1 in 6500 among whites, blacks, and Asians and 1 in 3800 among Hispanics. Most affected children (81%) had a heart defect, and many (1 in 3) had major extracardiac defects (other than velopalatal anomalies), including anomalies of the central nervous system. Overall, the deletion contributed to at least 1 of every 68 cases of major heart defects identified in the total birth cohort and, in particular, to 1 of every 2 cases diagnosed with interrupted aortic arch type B, 1 of every 5 with truncus arteriosus, and 1 of every 8 with tetralogy of Fallot. Conclusions. The 22q11.2 deletion was common in this birth population. The clinical phenotype included a wide and variable spectrum of major cardiac and extracardiac anomalies. From these population-based data, one can estimate that at least 700 affected infants are born annually in the United States. Population-based estimates such as these should be useful to medical professionals and policy makers in planning for the optimal care of people with the 22q11.2 deletion., ABBREVIATIONS. MACDP, Metropolitan Atlanta Congenital Defects Program; FISH, fluorescence in situ hybridization; CI, confidence interval. During the 2 decades after its initial identification in some children with the DiGeorge phenotype [...]

Objective. Although trisomy 13 and trisomy 18 are generally considered to be lethal, long-term survival of patients has been reported. We sought to evaluate mortality in people with trisomy 13 or 18 using 2 population-based strategies. Methods. In the first analysis, infants who had trisomy 13 or 18 and were born during 1968-1999 were identified using the Metropolitan Atlanta Congenital Defects Program, a population-based birth defects surveillance system. Dates of death were documented using hospital records, Georgia vital records, and the National Death Index. In the second analysis, we used the Multiple-Cause Mortality Files compiled from US death certificates from 1979 through 1997. Using these 2 analyses, we examined median survival time or median age at death, survival beyond 1 year of age, and factors associated with longer survival. Results. Using Metropolitan Atlanta Congenital Defects Program, we identified 70 liveborn infants with trisomy 13 and 114 liveborn infants with trisomy 18. Median survival time was 7 days (95% confidence interval [CI]: 3-15) for people with trisomy 13 and 14.5 days (95% CI: 8-28) for people with trisomy 18. For each condition, 91% of infants died within the first year. Neither race nor gender affected survival for trisomy 13, but for trisomy 18, girls and infants of races other than white seemed to survive longer. The presence of a heart defect did not seem to affect survival for either condition. Using MCMF, we identified 5515 people with trisomy 13 and 8750 people with trisomy 18 listed on their death certificates. Median ages at death for people with trisomy 13 and trisomy 18 both were 10 days; 5.6% of people with trisomy 13 and 5.6% of people with trisomy 18 died at age 1 year or greater. Race and gender seemed to affect survival in both conditions, with girls and blacks showing higher median ages at death. Conclusions. Although survival is greatly affected by trisomy 13 and trisomy 18, 5% to 10% of people with these conditions survive beyond the first year of life. These population-based data are useful to clinicians who care for patients with these trisomies or counsel families with infants or fetuses who have a diagnosis of trisomy 13 or 18. Pediatrics 2003;111:777-784; trisomy 13, trisomy 18, survival, mortality., ABBREVIATIONS. MACDP, Metropolitan Atlanta Congenital Defects Program; MCMF, Multiple-Cause Mortality Files; ICD-9-CM, International Classification of Diseases, Ninth Revision, Clinical Modification; NDI, National Death Index; CI, confidence interval; ICD-9, International Classification [...]

Women who take folic acid up until the time of their pregnancy and through the first trimester can reduce their baby's risk of having a neural tube defect. Neural tube defects occur when the spinal column does not close completely around the spinal cord. Spina bifida is an example of a neural tube defect. The northern region of China has a higher rate of neural tube defects than the southern region. A study of approximately 250,000 Chinese women, half of whom began taking folic acid, found that these women had a lower rate of neural tube defects regardless of which region they lived in.

BACKGROUND: 2,4-Dichlorophenol (2,4-DCP), 2,5-dichlorophenol (2,5-DCP), and their precursors are widely used in industry and in consumer products. Urinary concentrations of these dichlorophenols (DCPs) have been measured as part of four National Health and Nutrition Examination Survey (NHANES) cycles in order to assess the exposure to these compounds or their precursors among the general U.S. population. OBJECTIVES: We identified predictors and evaluated trends in DCP concentrations according to race/ethnicity, age, sex, family income, and housing type. METHODS: We used analysis of covariance to examine associations of various demographic parameters and survey cycle with urinary concentrations of DCPs during NHANES 2003-2010. We also conducted weighted logistic regressions to estimate associations of DCP concentrations above the 95th percentile with housing type, race/ethnicity, and income. RESULTS: We detected DCPs in at least 81% of participants. Geometric mean (GM) urinary concentrations were higher for 2,5-DCP (6.1-12.9 Hg/L) than 2,4-DCP (0.8-1.0 µg/L) throughout 2003-2010. Adjusted GM concentrations of the DCPs among children (6-11 years of age) and adults > 60 years of age were higher than among adolescents and other adults. Adjusted GM concentrations among non-Hispanic whites were lower than among non-Hispanic blacks and Mexican Americans, although differences according to race/ ethnicity were less pronounced among participants in high-income households. Among non-Hispanic blacks and Mexican Americans, adjusted GM concentrations were lowest among high-income participants relative to other income groups, with a monotonic decrease with increasing income among Mexican Americans. Type of housing and race/ethnicity were significant predictors of DCP urinary concentrations above the 95th percentile. Furthermore, urinary DCP concentrations have showed a downward trend since 2003. CONCLUSIONS: Exposure to DCPs and their precursors was prevalent in the general U.S. population in 2003-2010. We identified age and race/ethnicity, family income, and housing type as predictors of exposure to these compounds. CITATION: Ye X, Wong LY, Zhou X, Calafat AM. 2014. Urinary concentrations of 2,4-dichlorophenol and 2,5-dichlorophenol in the U.S. population (National Health and Nutrition Examination Survey, 2003-2010): trends and predictors. Environ Health Perspect 122:351-355; http://dx.doi.org/10.1289/ehp.1306816, Introduction 2,5-Dichlorophenol (2,5-DCP) is a major metabolite of 1,4-dichlorobenzene (1,4-D), which has been used as a chemical intermediate for the manufacture of dyes and pharmaceutical and agricultural products, as a [...]