Perfluorinated compound levels in cord blood and neurodevelopment at 2 years of age.

BACKGROUND: Epidemiologic data regarding the potential neurotoxicity of perfluorinated compounds (PFCs) are inconclusive. We investigated the associations between in utero exposure to perfluorooctanoic acid (PFOA) and perfluorooctyl sulfonate (PFOS) and early childhood neurodevelopment. METHODS: We recruited 239 mother-infant pairs in northern Taiwan from the Taiwan Birth Panel Study, which was established in 2004. We examined the association between PFCs in cord blood and children's neurodevelopment at 2 years of age, using the Comprehensive Developmental Inventory for Infants and Toddlers. This tool contains cognitive, language, motor, social, and self-help domains; test scores were further transformed into developmental quotients according to standardized norms. All multivariate regression models were adjusted for infant sex and gestational age, maternal education, family income, cord blood cotinine levels, postnatal environmental tobacco smoke exposure, and breastfeeding. RESULTS: Prenatal PFOS concentrations in both untransformed and natural log (Ln)-transformed values were associated with adverse performance on the whole test and the domains related to development. A dose-response relationship was observed when PFOS levels were categorized into four groups. This association was most obvious in relation to the gross-motor subdomain. Across the PFOS interquartile range, the quotients of the gross-motor subdomain decreased by 3.7 points (95% confidence interval [CI] = -6.0 to -1.5), with an increasing odds ratio of poor performance (2.4; 95% CI = 1.3 to 4.2). In contrast, measures of association between PFOA concentrations and test scores were close to null. CONCLUSIONS: Prenatal exposure to PFOS, but not PFOA, may affect children's development, especially gross-motor development at 2 years of age.

Associations between levels of serum perfluorinated chemicals and adiponectin in a young hypertension cohort in Taiwan.

In animals, perfluorinated chemicals (PFCs), specifically perfluorooctanoic acid (PFOA) and perfluorooctane sulfate (PFOS), function as peroxisome proliferator-activated receptor (PPAR) alpha agonists. However, the relevance of animal (primarily rodent) data to humans is unresolved. While plasma adiponectin level is very responsive to PPAR gamma agonist drugs, it has not been determined whether adiponectin level is related to serum PFCs concentrations. In the present study, 287 subjects (12-30 years of age) were recruited to determine the relationship between serum level of PFCs and serum level of adiponectin. The results showed males had higher serum PFOS concentrations than females and that those with metabolic syndrome had lower serum PFOA than controls. Besides, it showed regional elevations of the perfluoroundecanoic acid (PFUA) (median concentration: 7.11 ng/mL) in the study subjects. No relationship of PFOA, PFOS, PFUA, and the sum of all four PFCs was found to glucose homeostasis, adiponectin level, lipid profile, and inflammatory markers. The median and the range of perfluorononanoic acid (PFNA) concentration (in ng/mL; for four categories corresponding to the <50, 50-74, 75-89, and ≥90th percentiles) were 0.38 (0.38-1.68), 3.22 (1.73-4.65), 5.85 (4.75-8.29), 10.56 (8.40-25.40), respectively. After controlling for confounding factors, multiple linear regression analysis revealed that the mean natural log-transformed level of adiponectin increased significantly across categories of PFNA (in ng/mL; 8.78, 8.73, 9.06, 9.36; P for trend = 0.010 in the full model). In conclusion, higher serum PFNA concentration is associated with elevated serum adiponectin concentration.

Validation of Dose Conversion of Banxia Houpotang Based on Systematic Evaluation / 中国实验方剂学杂志

There are many different opinions on dose conversion of famous classical formulas from Treatise on Febrile Diseases or Synopsis of the Golden Chamber, which has become a difficult point in research and development of famous classical formulas. At present, the clinical application dose of Banxia Houpotang is similar to the viewpoint that 1 Liang is equivalent to 3 g, in order to provide scientific basis for this conversion method, this paper systematically evaluated the effectiveness of Banxia Houpotang in intervening globus hystericus. Randomized controlled trials (RCTs) of Banxia Houpotang in intervening globus hystericus from CNKI, VIP, Wanfang Data, China Biology Medicine (CBM), Web of Science and PubMed databases were collected online, the retrieval time was from inception to April 1, 2019. Two reviewers independently screened the literature, extracted the data and assessed the risk of bias of the included studies. Then, Meta analysis was performed by RevMan 5.3 software. A total of 17 RCTs involving 1 575 patients were included. The effective rate [relative risk (RR)=1.24, 95%confidence interval (CI) (1.18, 1.30), P<0.000 01] and the curative rate [RR=1.76, 95%CI (1.45, 2.15), P<0.000 01] of Banxia Houpotang in intervening globus hystericus were all better than the control group. Current evidence shows that Banxia Houpotang under the conversion of 3 g in 1 Liang has a significant effect on intervention of globus hystericus. Due to the limitations of quantity and quality of the included studies, the above conclusions need to be verified by more high-quality studies, but the author suggests that such dose conversion should be considered in the research and development of famous classical formulas.

Association between levels of serum perfluorooctane sulfate and carotid artery intima-media thickness in adolescents and young adults.

BACKGROUND: Perfluorinated chemicals (PFCs) have been widely used for years in a variety of products worldwide. Although epidemiological findings have shown that PFC levels are positively associated with cholesterol and uric acid levels, it is unknown whether PFCs are associated with atherosclerosis. METHODS: We recruited 664 subjects (12-30 years) from a population-based sample of adolescents and young adults based on a mass urine screening to determine the relationship between serum levels of PFCs and carotid intima-media thickness (CIMT). RESULTS: The median concentrations and ranges of perfluorooctanoic acid (PFOA), perfluorooctane sulfate (PFOS), perfluorononanoic acid (PFNA), and perfluorodecanoic acid (PFUA) were 3.49 (0.75-52.2) ng/mL, 8.65 (0.11-85.90) ng/mL, 0.38 (0.38-25.4) ng/mL, and 6.59 (1.50-105.7) ng/mL, respectively. After controlling for age, gender, smoking status, systolic blood pressure, body mass index, low-density lipoprotein cholesterol, triglyceride, high-sensitivity C-reactive protein, and homeostasis model assessment of insulin resistance, multiple linear regression analysis revealed that CIMT increased significantly across quartiles of PFOS (0.434 mm, 0.446 mm, 0.458 mm, 0.451 mm; P for trend <0.001). Subpopulation analysis showed the association between PFOS and CIMT was more evident and significant in females, non-smokers, subjects of age 12-19 years, BMI<24, and those with APOE genotype of E2 carrier and E3/E3. CONCLUSIONS: Higher serum concentrations of PFOS were associated with an increase of carotid IMT in this cohort of adolescents and young adults. Further studies are warranted to clarify the causal relationship between PFOS and atherosclerosis.

The associations between serum perfluorinated chemicals and thyroid function in adolescents and young adults.

Perfluorinated chemicals (PFCs) have been widely used in a variety of products worldwide for years. However, the effect of PFCs on thyroid function has not yet been clearly defined. We recruited 567 subjects (aged 12-30 years) in a population-based cohort of adolescents and young adults with abnormal urinalysis in the childhood to determine the relationship between serum level of PFCs and the levels of serum free thyroxine (T4) and thyroid stimulating hormone (TSH). The geometric means and geometric standard deviation concentrations of perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), perfluorononanoic acid (PFNA) and perfluoroundecanoic acid (PFUA) were 2.67 (2.96) ng/ml, 7.78 (2.42) ng/ml, 1.01 (3.48) ng/ml and 5.81 (2.92) ng/ml, respectively. Differences in the levels of free T4 and TSH across different categories of PFOA, PFOS and PFUA were insignificant. After controlling for confounding factors, multiple linear regression analyses revealed mean serum level of free T4 increased significantly across categories (<60th, 60-89 and >90th percentiles) of PFNA (P for trend =0.012 in the full model). The association between PFNA and free T4 was more significant in male subjects in age group 20-30, active smokers and in those with higher body mass index in stratified analysis. Serum concentrations of PFNA were associated with serum free T4 levels in adolescents and young adults.

Perfluorinated compounds in umbilical cord blood and adverse birth outcomes.

BACKGROUND: 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. METHODS: 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. RESULTS: 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 ß (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. CONCLUSIONS: An adverse dose-dependent association was observed between prenatal PFOS exposure and birth outcomes. However, no associations were found for the other examined PFCs.

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 µm) 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.