Patterns of lung cancer mortality in 23 countries: Application of the Age-Period-Cohort model

BACKGROUND: Smoking habits do not seem to be the main explanation of the epidemiological characteristics of female lung cancer mortality in Asian countries. However, Asian countries are often excluded from studies of geographical differences in trends for lung cancer mortality. We thus examined lung cancer trends from 1971 to 1995 among men and women for 23 countries, including four in Asia. METHODS: International and national data were used to analyze lung cancer mortality from 1971 to 1995 in both sexes. Age-standardized mortality rates (ASMR) were analyzed in five consecutive five-year periods and for each five-year age group in the age range 30 to 79. The age-period-cohort (APC) model was used to estimate the period effect (adjusted for age and cohort effects) for mortality from lung cancer. RESULTS: The sex ratio of the ASMR for lung cancer was lower in Asian countries, while the sex ratio of smoking prevalence was higher in Asian countries. The mean values of the sex ratio of the ASMR from lung cancer in Taiwan, Hong Kong, Singapore, and Japan for the five 5-year period were 2.10, 2.39, 3.07, and 3.55, respectively. These values not only remained quite constant over each five-year period, but were also lower than seen in the western countries. The period effect, for lung cancer mortality as derived for the 23 countries from the APC model, could be classified into seven patterns. CONCLUSION: Period effects for both men and women in 23 countries, as derived using the APC model, could be classified into seven patterns. Four Asian countries have a relatively low sex ratio in lung cancer mortality and a relatively high sex ratio in smoking prevalence. Factors other than smoking might be important, especially for women in Asian countries

Height and body-mass index trajectories of school-aged children and adolescents from 1985 to 2019 in 200 countries and territories: a pooled analysis of 2181 population-based studies with 65 million participants

Summary Background Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents. Methods For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5–19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence. Findings We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9–10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing countries, but they became progressively less healthy compared with their comparators as they grew older by not growing as tall (eg, boys in Austria and Barbados, and girls in Belgium and Puerto Rico) or gaining too much weight for their height (eg, girls and boys in Kuwait, Bahrain, Fiji, Jamaica, and Mexico; and girls in South Africa and New Zealand). In other countries, growing children overtook the height of their comparators (eg, Latvia, Czech Republic, Morocco, and Iran) or curbed their weight gain (eg, Italy, France, and Croatia) in late childhood and adolescence. When changes in both height and BMI were considered, girls in South Korea, Vietnam, Saudi Arabia, Turkey, and some central Asian countries (eg, Armenia and Azerbaijan), and boys in central and western Europe (eg, Portugal, Denmark, Poland, and Montenegro) had the healthiest changes in anthropometric status over the past 3·5 decades because, compared with children and adolescents in other countries, they had a much larger gain in height than they did in BMI. The unhealthiest changes—gaining too little height, too much weight for their height compared with children in other countries, or both—occurred in many countries in sub-Saharan Africa, New Zealand, and the USA for boys and girls; in Malaysia and some Pacific island nations for boys; and in Mexico for girls. Interpretation The height and BMI trajectories over age and time of school-aged children and adolescents are highly variable across countries, which indicates heterogeneous nutritional quality and lifelong health advantages and risks

Rising rural body-mass index is the main driver of the global obesity epidemic in adults

Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities(.)(1,2) This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity(3-6). Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017-and more than 80% in some low- and middle-income regions-was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing-and in some countries reversal-of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.Peer reviewe

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight NCD Risk Factor Collaboration (NCD-RisC)

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions

Analysis of Perfluorinated Chemicals in Umbilical Cord Blood by Ultra-High Performance Liquid Chromatography/Tandem Mass Spectrometry

Perfluorinated compounds (PFCs) can cross the placental barrier and enter fetal circulation. This study aimed at developing a fast and sensitive ultra-high performance liquid chromatography/tandem mass spectrometry method for the determination of twelve perfluorinated compounds in cord blood. Samples were processed with protein precipitation using formic acid and methanol, mixed with stable isotope labeled standard, followed by sonication and centrifugation, and were analyzed using a Waters ACQUITY UPLC coupled with a Waters Quattro Premier XE triple-quadrupole mass spectrometer. The instrument was operated in selected reaction monitoring (SRM) with negative electrospray ionization. Using BEH C(18) column (2.1 mm 50 mm, 1.7 m) with 10-mM N-methylmorpholine/methanol gradient elution provided a fast chromatographic separation (5.5 min) and sharp peaks. Intra- and inter-day calibration bias was less than 7% and intra- and inter-day calibration of relative standard deviations were within 0.02 -8.22% for all the analytes and concentrations. The recoveries of PFCs spiked into bovine serum ranged from 85 to 104% with relative standard deviations from 0.02 to 6.37%. The limits of quantitation (LOQs), defined as a signal-to-noise ratio of ten, ranged from 0.15 to 3.1 ng/mL for the twelve PFCs. Perfluorooctanoic acid (PFOA), perfluorooctyl sulfonate ( PFOS), perfluoroundecanoic acid (PFUA) and perfluorononanoic acid (PFNA) were detected in up to 68% of umbilical cord plasma (n=444) in Taiwan Birth Panel Study and the health effect of these chemicals on children developmental deserves further investigation

Neonatal-maternal factors and perfluoroalkyl substances in cord blood

Perfluoroalkyl substances (PFASs) can cross the placenta, enter fetal circulation, and were found to correlate with adverse fetal growth. However, determinants of cord blood PFASs are not fully characterized. The study aimed to explore the association between PFASs and neonatal-maternal factors within a Taiwanese birth cohort. We selected subjects from Taiwan Birth Panel Study, which enrolled 486 infant-mother pairs in 2004-2005. We collected cord blood and analyzed perfluorooctanoic acid (PFOA), perfluorooctanyl sulfonate (PFOS), perfluorononanoic acid (PFNA) and perfluoroundecanoic acid (PFUA) using a simple protein precipitation and an ultra-high performance liquid chromatography/tandem mass spectrometry. We retrieved information pertaining to maternal socio-demographics, lifestyle- and dietary-related factors through structured questionnaires during the postpartum hospital stay. A total of 439 subjects, with 90% response rate, have completed serum analysis and questionnaire survey. The median concentrations for PFOA, PFOS, PFNA, and PFUA in cord blood were 1.86, 5.67, 3.00, and 13.5 ng mL(-1), respectively. After adjusting for potential confounders, multiple linear regression models revealed that log(10)-PFOA was positively associated with maternal age (beta = 0.011) and negatively associated with multiparity (beta = -0.044). Log(10)-PFOS was negatively correlated with birth weight (beta = -0.011) and higher maternal education (senior high school: beta = -0.067; university: beta = -0.088). Log(10)-PFUA tended to negatively associate with gender, male infants (beta = -0.075), and using cosmetics during pregnancy (beta = -0.065). Interestingly, presence of cockroaches in the home was positively associated with log(10)-PFOA (beta = 0.041) and log(10)-PFNA (beta = 0.123). In conclusion, this study demonstrated several factors to correlate with cord blood PFASs and further investigation are still needed for confirmation of exposure routes. (C) 2013 Elsevier Ltd. All rights reserved

Perfluoroalkyl substances in cord blood and attention deficit/hyperactivity disorder symptoms in seven-year-old children

Objective: The effect of perfiuoroalkyl substances (PFASs) on the development of neurotoxicity in children is still controversial. This study aimed to evaluate the association between in utero exposure to four PFASs and the development of neurobehavioral symptoms related to attention deficit hyperactivity disorder (ADHD) in early childhood. ;Methods: Eligible study subjects were selected from the Taiwan Birth Panel Study and the Taiwan Early Life Cohort, which enrolled a total of 1526 mother-infant pairs during 2004 and 2005. We collected umbilical cord blood and analyzed perfluorooctanoic acid (PFOA), perfluorooctanyl sulfonate (PFOS), perfluorononanoic acid (PFNA), and perfiuoroundecanoic acid (PFUA) levels. When a child was 7 years old, to evaluate ADHD related neurobehavioral symptoms, their parents completed the Swanson, Nolan, and Pelham IV scale (SNAP-IV), the Child Behavior Checklist (CBCL), and the Strengths and Difficulties Questionnaire (SDQ) questionnaires. We used linear regression models with inverse probability weighting to explore the association between prenatal exposure to four PFASs and ADHD rating scores. ;Results: A total of 282 subjects have completed the PFASs analysis and questionnaire survey. After adjusted for potential confounders, we observed that PFNA is inversely associated with inattention and oppositional defiant disorder of SNAP-IV, and hyperactivity/inattention of SDQ. No association between PFOA, PFOS, or PFUA and ADHD symptoms was found. ;Conclusions: Prenatal exposure to PFNA was found to associate with neurobehavioral symptoms related to ADHD among Asian seven-year-old children. Further studies are needed to elucidate the causal relationship. (C) 2016 Published by Elsevier Ltd

Determination of Feminizing Chemicals in Water using Ultra-Performance Liquid Chromatography/Tandem Mass Spectrometry: Method Development and Applications

分布於環境水體的雌激性內分泌干擾物質 (estrogenic enocrine-disrupting chemicals, EDCs)，濃度雖低，卻可能足以改變水生生物的生殖表現。這些受汙染的表面水若進入飲用水源，可能干擾人類的內分泌系統。目前這類活性物質在各淨水處理單元的含量和移除所知有限，主因為其所含之EDCs濃度甚低，不易分析。因此，本研究目的是開發極致液相層析/串聯式質譜儀 (UPLC/MS/MS) 結合化學衍生，並透過層析技術降低真實樣品的基質干擾，以改進偵測在水環境中EDCs的靈敏度。DCs若具有酚類官能基，可與丹磺酰氯 (dansyl chloride) 或五氟溴甲苯(pentafluorobenzyl bromide, PFBBr) 化學試劑進行衍生反應，以增強待測物在液相層析/串聯式質譜儀之游離效率，改善偵測之靈敏度。本研究針對雌素酮 (estrone, E1)、動情激素 (17β-estradiol, E2)、雌素醇 (estriol, E3)、乙炔動情激素 (17α-ethinyl estradiol, EE2)、壬基酚 (4-nonylphenol, NP)、辛基酚 (4-tert-octylphenol, OP)、雙酚A (bisphenol A, BPA) 以及合成丹磺酰氯和五氟溴甲苯衍生之待測物，進行電灑游離法 (electrospray ionization, ESI)、大氣壓化學游離法 (atmospheric pressure chemical ionization, APCI)、大氣壓光游離法 (atmospheric pressure photoionization, APPI)，以及APCI/APPI雙重游離等四種游離源之靈敏度比較，同時評估極致液相層析管柱 (UPLC column)、管柱後分流 (post-column split)、複合式管柱 (mixed-mode column) 以及二維層析 (2D-LC) 四種方法之基質效應與方法表現。研究採集原水 (raw water) 基質，於固相萃取後添加標準品 (post-extraction addition)，以Waters 極致液相層析 (Acquity UPLC) 結合 Waters Quattro Premier XE三段式四極棒質譜儀 (triple-quadrupole mass spectrometer) 分析。結果顯示，未衍生之待測物在電灑游離法、丹磺酰氯衍生之待測物在三種游離法 (除大氣壓光游離法之外) 和五氟溴甲苯衍生之待測物在大氣壓化學游離法，於上述四種層析方法之間，其基質效應並無顯著差異。磺酰氯衍生之待測物於電灑游離法具有優異之偵測靈敏度，其次是大氣壓光游離法，兩者訊號強度相較於未衍生之待測物均可提升三個數量級 (order of magnitude)。五氟溴甲苯衍生之待測物，其訊號強度亦可高於未衍生之待測物一個數量級。丹磺酰氯衍生之待測物在四種游離源下的訊號強度均優於五氟溴甲苯衍生之待測物。待測物在雙重APCI/APPI游離法和單一APCI游離法的訊號強度旗鼓相當，顯示雙重游離模式並未增強離子化效率。整體而言，以電灑游離法配合丹磺酰氯衍生技術並採用極致液相層析下，擁有最佳的靈敏度且相對上基質效應較低。研究進一步以UPLC/ESI(+)/MS/MS結合丹磺酰氯衍生技術，採集河水和汙水處理廠之放流水進行方法驗證 (method validation)；丹磺酰氯衍生之待測物 (E1, E2, E3 and EE2) 採用選擇性離子偵測 (selected ion monitoring, SIM) 和選擇性反應偵測 (selected reaction monitoring, SRM) 的on-column偵測極限，定義為三倍的訊雜比，分別為 0.44-1.5 pg以及0.05-0.20 pg，而污水處理廠之放流水和河水採選擇性反應偵測的偵測極限分別為0.23-0.52 ng/L 以及 0.56-0.91 ng/L。 本研究亦針對五個代表性飲用水淨水廠於不同單元之樣本進行檢測。類固醇雌激素於原水採選擇性離子偵測和選擇性反應偵測時之偵測極限分別為0.20-0.68 ng/L 和0.04-0.15 ng/L。原水中類固醇雌激素濃度範圍介於 < LOD-5.5 ng/L，透過多步驟淨水處理單元已明顯降低，清水中的濃度範圍則介於 < LOD-1.17 ng/L。壬基酚於各淨水單元皆能檢出，其濃度變異較大，介於25-378 ng/L; 而清水中的壬基酚濃度則低於83 ng/L。辛基酚和雙酚A於各淨水單元的濃度，則近於分析背景值。儘管各水廠水源不同，原水中類固醇雌激素濃度相似; 透過傳統處理或增設高級處理程序，清水中的濃度並無顯著差異。 開發偵測水體中雌激性化合物定性兼定量分析方法，加速樣本液相層析分離的速度 (< 5 min)，而且在搭配化學衍生後，環境樣本採用選擇性離子偵測模式 (單一質譜) 的偵測極限亦可達sub-ng/L，且其所定量之濃度與選擇性反應偵測模式 (串聯式質譜) 所量測者相符為本研究重要貢獻。此外，本研究發展之相關分析技術可拓展至其他基質或化合物，例如組織、血液和食品樣本，為微量有機分析另闢蹊徑。大規模的飲用水廠檢測證實EDCs確實存在飲用水中，特別是雌素酮、乙炔動情激素和壬基酚化合物。水處理技術成本高，對於這些微汙染物 (濃度接近偵測極限) 能再進一步改善移除效果的空間有限；相較之下，原水水源的保護和降低汙染來源可能是更為有效的作法。Estrogenic endocrine-disrupting chemicals (EDCs) are widely distributed over the aquatic environment and may interfere with reproductive functions of aquatic creatures even at trace levels. EDCs may also disturb the endocrine system of human beings if they exist in drinking water. Currently little is known about the levels and removal of these bioactive substances in each step of drinking water treatment. One of the major obstacles to the relating studies is how to detect trace amount of EDCs in complex environmental matrixes. This study aimed at employing ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) coupled with chemical derivatization and decreasing the matrix effects from real samples through chromatographic technique to improve the detection sensitivity of EDCs in water.erivatization of phenolic EDCs using dansyl chloride and pentafluorobenzyl bromide (PFBBr) can enhance the ionization efficiency and improve the sensitivity on MS. Consequently, this study compared the sensitivities and matrix effects of four ionization methods combined with four liquid chromatographic systems on estrone (E1), 17β-estradiol (E2), estriol (E3), 17α-ethinylestradiol (EE2), 4-nonylphenol (NP), 4-tert-octylphenol (OP), bisphenol A (BPA) and their derivatives of dansyl chloride or PFBBr. The four ion sources were electrospray ionization (ESI), atmospheric pressure chemical ionization (APCI), atmospheric pressure photoionization (APPI) and APCI/APPI, respectively; the four liquid chromatography (LC) systems were UPLC method with and without post-column split (5:1), a mixed mode column and two-dimensional LC (2D-LC) method. his study evaluated the matrix effects and the performance of ionization methods using raw water with post-extraction spike. The analysis was carried out using a Waters Acquity UPLC coupled with a Waters Quattro Premier XE triple-quadrupole mass spectrometer. The results showed no significant differences in matrix effects among native analytes using ESI, dansylated analytes using each ion source except for APPI, and PFBBr derivatives using APCI for the above four LC methods. ansylated compounds produced the most intense signals using ESI and then APPI, which were both up to three orders of magnitude than that without derivatization. PFBBr derivatization increased the signal intensity of analytes up to one order of magnitude than those of underivatized ones. The signal intensity of dansylated compounds was higher than those of PFBBr derivatives. The response of analytes using APCI/APPI mode was similar to that at APCI mode; the dual-source ionization did not improve the signals.ansylated compounds using ESI under UPLC system yielded the strongest signals and were less susceptible to matrix effect; consequently, this combination was further evaluated and validated by sewage treatment plant effluents and river water. The on-column detection limit of dansylated compounds (E1, E2, E3 and EE2) using selected ion monitoring (SIM) and selected reaction monitoring (SRM) modes, defined as a signal-to-noise ratio of three, ranged from 0.44 to 1.5 pg and from 0.05 to 0.20 pg, respectively. The limits of detection (LODs) with SRM in sewage treatment plant effluents and river water were 0.23-0.52 and 0.56-0.91 ng/L, respectively.sing the developed method, the study surveyed the levels of these EDCs in different treatment steps of five representative drinking water treatment plants. The LODs of steroid estrogens in raw water with SIM and SRM were 0.20-0.68 ng/L and 0.04-015 ng/L, respectively. The four steroid estrogens in raw water and finished water ranged from < LOD to 5.5 ng/L and < LOD to 1.17 ng/L, respectively. NP survived in each treatment step and the concentrations ranged from 25 to 378 ng/L, and its levels in finished water were all below 83 ng/L. The levels of OP and BPA in most samples were close to the backgrounds in lab blanks. The levels of the steroid estrogens in raw water were similar among the five plants even though their locations and water sources are different. Most of the estrogenic chemicals can be removed effectively through drinking water treatment steps except for NP, and there were no differences in the removal efficiency between conventional steps only and those with additional advanced procedures. n conclusion, this study developed and validated a qualitative and quantitative method on detecting EDCs with dansyl chloride derivatization by UPLC/MS and UPLC/MS/MS. The new method provided a fast chromatographic separation (< 5 min) and the LODs of the EDCs in environmental waters using SIM reached low-ng/L, and the quantitative results were comparable with those of SRM. In addition, levels of the analytes were not significantly different in the finished water between conventional and advanced treatment processes; the four estrogens at levels of few ng/L cannot be further reduced after the treatment of activated carbon adsorption or reverse osmosis process. It is still essential to prevent water sources from contaminations of EDCs.誌 謝 i文摘要 iiiBSTRACT viIST OF FIGURES xiiIST OF TABLES xiiihapter One: Introduction 1.1 Backgrounds 1.2 Objectives 12hapter Two: Materials and Methods 15.1 Chemicals and reagents 15.2 Extraction 16.3 Synthesis of derivatized products 16.3.1 Dansyl chloride derivatization 16.3.2 PFBBr derivatization 18.4 LC systems and analytical columns 18.4.1 The UPLC with or without post-column split 18.4.2 The mixed-mode column 19.4.3 2D-LC system with RAM pre-column 19.5 Instrumental Analysis 20.5.1 Dansyl derivatives 21.5.2 PFBBr derivatives 24.5.3 Native analytes 24.6 Method comparisons 27.7 Method validation 28.8 Sample collection of drinking water 29.9 QA/QC, quantification and data analysis 30hapter Three: Results and Discussion 33.1 Comparisons between ESI, APPI, APCI and APCI/APPI 33.1.1 Effects of dopant, mobile phase flow rates and compositions on APPI sensitivity 33.1.2 Sensitivity among different LC systems and ionization modes for both derivatized and underivatized analytes 36.1.3 Matrix effects 38.1.4 Method validation 40.2 Levels of feminizing chemicals in drinking water treatment processes 44.2.1 Method recovery and detection limits 44.2.2 Steroid estrogens in the five drinking water treatment plants (DWTPs) 45.2.3 Xenoestrogens in the five drinking water treatment plants (DWTPs) 48hapter Four: Conclusions 51CKNOWLEDGENTS 54EFERENCES 55IGURES 63ABLES 77ELATED PUBLISHED PAPERS 94PPENDICES 97PPENDIX A: Glossary 97PPENDIX B: Chromatograms of native analytes in ESI mode 98PPENDIX C: Chromatograms of PFBBr derivatized analytes in APCI mode 99PPENDIX D:Chromatograms of background NP, OP and their derivatives in different samples 10

Perfluorinated compounds in umbilical cord blood and adverse birth outcomes.

Previous animal studies have shown that perfluorinated compounds (PFCs) have adverse impacts on birth outcomes, but the results have been inconclusive in humans. We investigated associations between prenatal exposure to perfluorooctanoic acid (PFOA), perfluorooctyl sulfonate (PFOS), perfluorononanoic acid (PFNA), and perfluoroundecanoic acid (PFUA) and birth outcomes.In total, 429 mother-infant pairs were recruited from the Taiwan Birth Panel Study (TBPS). Demographic data were obtained by interviewing mothers using a structured questionnaire and birth outcomes were extracted from medical records. Cord blood was collected for PFOA, PFOS, PFNA, and PFUA analysis by ultra-high-performance liquid chromatography/tandem mass spectrometry.The geometric mean (standard deviation) levels of PFOA, PFOS, PFNA, and PFUA in cord blood plasma were 1.84 (2.23), 5.94 (1.95), 2.36(4.74), and 10.26 (3.07) ng/mL, respectively. Only PFOS levels were found to be inversely associated with gestational age, birth weight, and head circumference [per ln unit: adjusted β (95% confidence interval, CI) = -0.37 (-0.60, -0.13) wks, -110.2 (-176.0, -44.5) gm and -0.25 (-0.46, -0.05) cm]. Additionally, the odds ratio of preterm birth, low birth weight, and small for gestational age increased with PFOS exposure [per ln unit: adjusted odds ratio (OR) (95%CI) = 2.45 (1.47, 4.08), 2.61(0.85, 8.03) and 2.27 (1.25, 4.15)]. When PFOS levels were divided into quartiles, a dose-response relation was observed. However, PFOA, PFNA, and PFUA were not observed to have any convincing impact on birth outcomes.An adverse dose-dependent association was observed between prenatal PFOS exposure and birth outcomes. However, no associations were found for the other examined PFCs