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Research suggests that dietary supplements may be a source of exposure to phthalates, given that diethyl phthalate (DEP) or di-n-butyl phthalate (DBP) can be components of coatings that facilitate extended release or encapsulate dietary supplements. Using nationally representative data on a population of 12,281 adults ages 20 y + surveyed between 1999 and 2014 from the National Health and Nutrition Examination Survey (NHANES), we evaluated the association between dietary supplement use in relation to urinary phthalate metabolites of DEP (monoethyl phthalate, MEP) and DBP (mono-n-butyl phthalate, MBP). We examined associations pertaining to regular use of multivitamin/multimineral (MVMM) supplements, as well as regular use of any other non-MVMM supplement products, the number of non-MVMM supplement products used, as well as individual supplements potentially containing phthalates (exclusive of MVMM). For each urinary phthalate metabolite, results are presented as the minimally-adjusted and multivariable-adjusted ratio, comparing the geometric mean among users to non-users. In multivariable models, we observed a significant positive association between regular use of MVMM use and MEP, with persons using MVMM supplements having 11% higher geometric mean MEP than non-users (Ratio: 1.11; 95% CI: 1.04–1.20); no association was observed for MVMM in relation to MBP. No other significant multivariable-adjusted associations were observed, although power was limited in analyses of individual supplements. Associations did not markedly vary by gender; however, the associations of garlic supplement use with MEP and MBP varied by calendar time, with statistically significant positive associations observed in later years. A modest significant association was observed between MVMM use and MEP. No other significant associations were observed in our overall multivariable models. Follow-up on the positive association observed between garlic and urinary phthalate metabolite concentrations observed in later years in a well-powered, prospective study would further clarify study findings. • Evaluated supplement use in relation to urinary phthalate metabolites, MEP and MBP. • Multivitamin/multimineral (MVMM) use positively associated with MEP. • No association observed between MVMM use and MBP. • Use of garlic, fish oil, and probiotics not associated with MEP or MBP overall. • Garlic supplement use positively associated with MEP and MBP in later years. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) are environmentally persistent, potential metabolic disruptors of concern for infants. Mothers participating in the New Hampshire Birth Cohort Study (NHBCS) provided a plasma sample during pregnancy to measure concentrations of seven PFAS, and infant weight and length were abstracted from well-child visits between birth and 12 months. Sex-specific growth patterns of child body mass index (BMI) were fit using a growth mixture model (GMM) and the relative risk ratios (RRR) and 95% Confidence Intervals (95% CI) for the association of maternal plasma PFAS with BMI growth patterns during infancy were estimated by using multinomial logistic model for the group probabilities in the GMM. Four growth patterns were identified: Group 1) a steep increase in BMI during the first 6 months, then a leveling off; Group 2) a gradual increase in BMI across the year; Group 3) a steep increase in BMI during months 1–3, then stable BMI; and Group 4) a gradual increase in BMI with plateau around 3 months (reference group). For boys, higher maternal pregnancy perfluorooctanoate concentrations were associated with a 60% decreased chance of being in group 3 as compared to group 4, after adjusting for potential confounding variables (RRR = 0.4; 95% CI: 0.1, 0.9). For girls, higher maternal perfluorooctane sulfonate (PFOS) concentrations during pregnancy were associated with a higher likelihood of following the growth pattern of groups 2 (RRR = 2.5; 95% CI: 1.0, 6.1) and 3 (RRR = 2.8; 95% CI: 1.0, 7.6) as compared to group 4, adjusting for potential confounding variables. In this cohort, sex-specific associations of maternal plasma PFAS concentrations during pregnancy with growth patterns during the first year of life were observed, with greater BMI growth observed among infant girls born to mothers with higher pregnancy concentrations of PFOS. • Sex-specific growth patterns in infancy were fit using a growth mixture model. • Associations of PFAS with growth in infancy were sex-specific. • Among girls with higher prenatal PFOS, steeper BMI growth occurred during infancy. [ABSTRACT FROM AUTHOR]

Silicone wristbands act as passive environmental samplers capable of detecting and measuring concentrations of a variety of chemicals. They offer a noninvasive method to collect complex exposure data in large-scale epidemiological studies. We evaluated the inter-method reliability of silicone wristbands and urinary biomarkers in the New Hampshire Birth Cohort Study. A subset of study participants (n = 96) provided a urine sample and wore a silicone wristband for 7 days at approximately 12 gestational weeks. Women were instructed to wear the wristbands during all their normal activities. Concentrations of urinary compounds and metabolites in the urine and parent compounds in wristbands were compared. High detection rates were observed for triphenyl phosphate (76.0%) and benzophenone (78.1%) in wristbands, although the distribution of corresponding urinary concentrations of chemicals did not differ according to whether chemicals were detected or not detected in wristbands. While detected among only 8.3% of wristbands, median urinary triclosan concentrations were higher among those with triclosan detected in wristbands (9.04 ng/mL) than without (0.16 ng/mL). For most chemicals slight to fair agreement was observed across exposure assessment methods, potentially due to low rates of detection in the wristbands for chemicals where observed urinary concentrations were relatively low as compared to background concentrations in the general population. Our findings support the growing body of research in support of deploying silicone wristbands as an important exposure assessment tool. [ABSTRACT FROM AUTHOR]

Background Phthalate exposure is widespread. Prior research suggests that prenatal phthalate exposure may influence birth size and gestational duration, but published results have been inconsistent. Objective We quantified the relationship between maternal urinary phthalate concentrations and infant birth weight z-scores, length, head circumference, and gestational duration. Methods In a cohort of 368 women from the HOME Study, based in Cincinnati, OH, we measured nine phthalate metabolites representing exposure to six parent phthalate diesters in urine collected at approximately 16 and 26 weeks gestation. Infant birth size and gestational duration were abstracted from medical records. We used multivariable linear regression to estimate covariate adjusted associations between urinary phthalate metabolite concentrations and infant outcomes. Results In unadjusted models, we observed a negative association between monoethyl phthalate (MEP) and birth weight z-scores, while mono-3-carboxypropyl phthalate (MCPP) was positively associated with gestational duration. After covariate adjustment, phthalate metabolite concentrations were no longer associated with birth size or gestational duration. Conclusions In this cohort, urinary phthalate metabolite concentrations during pregnancy were not associated with infant birth size or gestational duration. Additional research is needed to determine if exposures during earlier periods of fetal development are associated with infant health. [ABSTRACT FROM AUTHOR]

Background Perfluoroalkyl substances (PFAS) may affect breast development and decrease duration of breastfeeding, thus interfering with the health benefits of breastfeeding. We investigated the association between maternal PFAS exposure and breastfeeding duration. Methods We measured PFAS concentrations in maternal serum collected during pregnancy in 2003–2006. After delivery, women (n=336) completed standardized breastfeeding surveys every 3 months until ending breastfeeding or 36 months postpartum. We estimated relative risks (RRs) for ending any breastfeeding within 3–6 months postpartum by Poisson regression, adjusted for relevant confounding factors. Results Women in the 4th quartile of perfluorooctanoic acid (PFOA) serum concentration had 1.77 times the risk of ending any breastfeeding by 3 months (95% confidence interval (CI): 1.23, 2.54; p-trend=0.003) and 1.41 times the risk of ending any breastfeeding by 6 months (95%CI: 1.06, 1.87; p-trend=0.038), compared with women in the first quartile. Women in the 4th quartile of perfluorooctane sulfonic acid serum concentration had a marginally increased risk of discontinuing any breastfeeding by 3 months (RR=1.32; 95%CI: 0.97, 1.79; p-trend=0.065). Conclusions Maternal serum PFOA concentrations were inversely related to duration of any breastfeeding in this cohort, even after controlling for prior breastfeeding. These findings suggest that PFOA exposure may adversely affect breastfeeding duration and highlight the need to consider the potential adverse effects of maternal environmental chemical exposure on breastfeeding. [ABSTRACT FROM AUTHOR]

Increasing evidence suggests an inverse association between cadmium (Cd) and size at birth, potentially greatest among female neonates. We evaluated whether greater maternal body burden of Cd is associated with reduced neonatal anthropometry (birthweight, birth length, head circumference, and ponderal index) and assessed whether these associations differ by infant sex. The analytic sample for the present study (n=396) was derived from a subcohort of 750 women randomly drawn from among all participants (N=4344) in the Omega Study, a prospective pregnancy cohort. Creatinine-corrected Cd in maternal clean-catch spot urine samples (U-Cd) was quantified by inductively coupled plasma mass spectrometry. Continuous log 2 -transformed Cd (log 2 -Cd) and U-Cd tertiles (low<0.29 μg/g creatinine, middle 0.29–0.42 μg/g creatinine, high≥0.43 μg/g creatinine) were used in multivariable linear regression models. Females had reduced birth length with greater U-Cd tertile, whereas males birth length marginally increased [β(95% CI) females: low=reference, middle=−0.59 cm (−1.37, 0.19), high=−0.83 cm (−1.69, 0.02), p-trend=0.08; males: low=reference, middle=0.18 cm (−0.59, 0.95), high=0.78 cm (–0.04, 1.60), p-trend=0.07; p for interaction=0.03]. The log 2 -Cd by infant sex interaction was statistically significant for ponderal index [p=0.003; β(95% CI): female=0.25 kg/m 3 (−0.20, 0.70); male=−0.63 kg/m 3 (−1.01, −0.24)] and birth length [p<0.001; β(95% CI): female=−0.47 cm (−0.74, −0.20), male=0.32 cm (0.00, 0.65)]. Our findings suggest potential sex-specific reversal of Cd’s associations on birth length and contribute to the evidence suggesting Cd impairs fetal growth. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA), an endocrine disruptor used in consumer products, may perturb thyroid function. Prenatal BPA exposure may have sex-specific effects on thyroid hormones (THs). Our objectives were to investigate whether maternal urinary BPA concentrations during pregnancy were associated with THs in maternal or cord serum, and whether these associations differed by newborn sex or maternal iodine status. We measured urinary BPA concentrations at 16 and 26 weeks gestation among pregnant women in the HOME Study (2003–2006, Cincinnati, Ohio). Thyroid stimulating hormone (TSH) and free and total thyroxine (T 4 ) and triiodothyronine (T 3 ) were measured in maternal serum at 16 weeks ( n =181) and cord serum at delivery ( n =249). Associations between BPA concentrations and maternal or cord serum TH levels were estimated by multivariable linear regression. Mean maternal urinary BPA was not associated with cord THs in all newborns, but a 10-fold increase in mean BPA was associated with lower cord TSH in girls (percent change=−36.0%; 95% confidence interval (CI): −58.4, −1.7%), but not boys (7.8%; 95% CI: −28.5, 62.7%; p -for-effect modification=0.09). We observed no significant associations between 16-week BPA and THs in maternal or cord serum, but 26-week maternal BPA was inversely associated with TSH in girls (−42.9%; 95% CI: −59.9, −18.5%), but not boys (7.6%; 95% CI: −17.3, 40.2%; p -for-effect modification=0.005) at birth. The inverse BPA–TSH relation among girls was stronger, but less precise, among iodine deficient versus sufficient mothers. Prenatal BPA exposure may reduce TSH among newborn girls, particularly when exposure occurs later in gestation. [ABSTRACT FROM AUTHOR]

Exposure to cadmium may contribute to the risk of gestational diabetes mellitus (GDM) and glucose intolerance during pregnancy. We examined 917 women enrolled from 2009 to 2017 in the New Hampshire Birth Cohort Study. Lifestyle, diet, demographic factors and pregnancy outcomes were collected by questionnaire and medical record review. Cadmium concentrations were measured in urine samples collected at 24–28 weeks gestation. Women were classified as normal (n = 815), glucose intolerant (n = 86), or GDM (n = 16) based on clinical data (i.e., glucose challenge test, oral glucose challenge test). We calculated odds ratios (OR) and 95% confidence intervals (CI), adjusting for potential confounders, using multinomial logistic regression to examine disease severity (normal, glucose intolerant, GDM) and logistic regression to examine the combined outcome of gestational hyperglycemia. Little to no association was observed for glucose intolerance (OR = 1.11, 95%CI 0.85–1.45) or GDM (OR = 0.86, 95% CI 0.51–1.44) with a doubling of urinary cadmium as compared to normal women. The combined outcome of gestational hyperglycemia yielded similar results (OR = 1.07, 95% CI 0.84–1.35). However, when stratified by pre-pregnancy body mass index (BMI), there was a slight association with the combined outcome in normal weight women (OR = 1.32, 95% CI 0.88–1.98) and no association in the overweight or obese women. This positive association remained in restricted analyses of only women with no exposure to smoking during pregnancy and those who had never smoked. Cadmium exposure was suggestively associated with increased risk of gestational hyperglycemia among women not already at increased risk of GDM due to being overweight or obese; however, associations of cadmium with gestational hyperglycemia were not statistically significant. • No strong associations were seen between cadmium and gestational hyperglycemia. • In normal weight women, cadmium and gestational hyperglycemia were weakly associated. • Positive association remained among never smokers with normal weight. [ABSTRACT FROM AUTHOR]

Background Triclosan, an antimicrobial agent used in some consumer products, reduces endogenous thyroid hormone concentrations in rodents. Despite ubiquitous triclosan exposure and the importance of thyroid hormones for normal fetal development, few human studies have examined the impact of triclosan exposure on maternal, neonatal, or child thyroid hormones. Methods In the HOME Study, a prospective cohort from Cincinnati, OH, we measured urinary triclosan concentrations up to three times in pregnant women between 16 weeks and delivery, and up to three times in children between age 1–3 years. We quantified serum concentrations of thyroid stimulating hormone and total and free thyroxine and triiodothyronine in mothers at 16-weeks gestation (n = 202), neonates at delivery (n = 274), and children at age 3 years (n = 153). We estimated covariate-adjusted differences in thyroid hormones with a 10-fold increase in triclosan using linear regression and multiple informants models. Results Triclosan was not associated with thyroid hormones during pregnancy. We observed a few associations of triclosan concentrations with thyroid hormone concentrations in neonates at delivery and children at age 3 years. Higher gestational triclosan, particularly around the time of delivery, was associated with lower cord serum total thyroxine (β: 0.3 μg/dL; 95% CI: − 0.6, − 0.0). Childhood triclosan, particularly at age 1 year, was positively associated with total thyroxine at age 3 years (β: 0.7 μg/dL; 95% CI: 0.3, 1.2). Conclusion Our findings suggest that triclosan exposure may influence some features of neonatal and early child thyroid function. Given the large number of comparisons we made, these findings should be replicated in other cohorts. [ABSTRACT FROM AUTHOR]

Perfluorooctanoic acid (PFOA), a perfluoroalkyl substance, is commonly detected in the serum of pregnant women and may impact fetal development via epigenetic re-programming. In a pilot study, we explored associations between serum PFOA concentrations during pregnancy and offspring peripheral leukocyte DNA methylation at delivery in women with high (n = 22, range: 12–26 ng/mL) and low (n = 22, range: 1.1–3.1 ng/mL) PFOA concentrations. After adjusting for cell type, child sex, and income, we did not find differences in CpG methylation in the two exposure groups that reached epigenome-wide significance. Among the 20 CpGs with the lowest p-values we found that seven CpG sites in three genes differed by exposure status. In a confirmatory cluster analysis, these 20 CpGs clustered into two groups that perfectly identified exposure status. Future studies with larger sample sizes should confirm these findings and determine if PFOA-associated changes in DNA methylation underlie potential health effects of PFOA. [ABSTRACT FROM AUTHOR]

Background Prenatal phthalate exposure has been associated with behavioral problems and lower performance on measures of cognitive ability in children. However, the potential effect of phthalate exposure during the sensitive preconception period is unknown. Objectives To estimate the association of maternal and paternal preconception urinary phthalate metabolite concentrations with child behavior and evaluate potential modification by child sex. Methods We used data from 166 children (111 singletons, 26 pairs of twins, and 1 set of triplets) born to 134 mothers and 100 fathers participating in a prospective preconception cohort study of subfertile couples from the Massachusetts General Hospital Fertility Center. We estimated mean maternal and paternal preconception exposures by averaging individual phthalate metabolite concentrations in multiple urine samples collected before pregnancy. We assessed children's behavior at 2–9 years of age by parent report using the Behavior Assessment System for Children-2 (BASC-2). We estimated the covariate-adjusted association between individual phthalate metabolite concentrations and the sum of di(2-ethylhexyl) phthalate metabolites (∑ DEHP) and behavior scores, and evaluated differences in associations by child sex using linear regression with Generalized Estimating Equations. Models were further adjusted for prenatal phthalate concentrations in sensitivity analyses. Results Each log e -unit increase in maternal and paternal preconception concentrations of ∑DEHP was associated with a 2.0 (95% CI: − 3.2, − 0.7) and 1.8 (95% CI: − 3.1, − 0.4) point decrease in BASC-2 internalizing behavior scores among all children, respectively. We observed sex-specific associations for some phthalate biomarkers: among boys, maternal monoisobutyl phthalate (MiBP) was positively associated with externalizing behaviors, and paternal MiBP and mono-n-butyl phthalate were positively associated with internalizing behaviors. Conclusions In this cohort, paternal and maternal preconception concentrations of some phthalate biomarkers were associated with specific aspects of child behavior, even after adjustment for prenatal concentrations. While additional research is warranted to confirm these results, our findings suggest that the preconception period of exposure may be a critical window for offspring neurodevelopment. [ABSTRACT FROM AUTHOR]

Skiers and snowboarders apply waxes and solvents to their equipment to enhance glide across the snow. Waxing results in exposures to per- and polyfluoroalkyl substances (PFAS) and particulate matter, which have been associated with adverse health effects among professional wax technicians in Scandinavia. However, little is known about exposure among people who participate at other levels of sport, including recreationally, in other regions. We sought to characterize wax-related exposures among US skiers and snowboarders who participate across numerous levels of sport to expand scientific understanding of environmental health risks among this population. We used an anonymous electronic survey to evaluate wax-related exposures among US cross-country and downhill skiers and snowboarders. Specifically, we assessed (Fang et al., 2020): duration of time involved with each sport in any role (Freberg et al., 2013), intensity of wax-related exposures based on time spent in waxing areas, wax use, and wax type (Rogowski et al., 2007), frequency of fluorinated wax application, and (Freberg et al., 2010) use of exposure interventions. Participants tended to be long-term winter sports enthusiasts (e.g., median downhill skiing duration: 31 years). Nearly all (92%) participants personally applied some wax to their skis/snowboards and most applied waxes containing PFAS (67%) and solvents (62%). Ski professionals waxed the most pairs of skis with fluorinated waxes annually (median (IQR): 20 (1, 100)), though individuals participating recreationally also applied fluorinated waxes regularly. Exposure interventions were not widely used. Waxing activities may pose significant risk of exposure to PFAS and other environmental contaminants among the US ski and snowboard community. Efforts are needed to reduce these exposures through changes to wax use patterns and broader adoption of exposure reduction strategies. • Fluorinated waxes are a source of PFAS exposure for skiers/snowboarders. • Most US skiers/snowboarders surveyed have applied PFAS-containing waxes. • Participants tend to wax multiple skis/snowboards each year, over many years. • Personal protective equipment use is more limited than institutional controls. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) are widespread pollutants and classified as potentially carcinogenic to humans. Although consumption of fish, seafood, and their byproducts is a known source of dietary PFAS exposure, little is known about the association between use of fish oil supplements and PFAS. Here, we examine associations between fish oil supplement use and serum PFAS concentrations. This analysis includes adults, ages 25 years of age and older, surveyed as part of the National Health and Nutrition Examinations Survey (NHANES). Outcomes include five serum PFAS compounds: perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorohexane sulphonic acid (PFHxS) and perfluorodecanoic acid (PFDA). To determine the association between fish oil use and log-transformed PFAS concentrations, survey-weighted linear regression was used to estimate multivariate-adjusted ratios between supplement-users' and non-users' geometric mean serum PFAS concentrations. No association was observed between fish oil use and PFAS. While results did not vary substantially by age, gender, study cycle, there was some indication of a potential inverse association in subgroups of interest. Specifically, an inverse association was observed between fish oil supplement use and PFOS levels in older adults, females, and in early calendar years; an inverse association was also observed between fish oil and PFNA in females and early calendar years. While fish oil users did not experience increased serum PFAS, there was an unexpected inverse association in some population subgroups. Further research will be needed to better understand whether this pattern reflects true differences, chance, or bias. • There is no strong association between fish oil supplements and serum PFAS levels. • Fish oil users have similar PFAS levels compared to non-users. • An inverse relation with fish oil and PFAS was seen in women, older adults, and early calendar years. [ABSTRACT FROM AUTHOR]

Gestational exposure to chemical mixtures, which is prevalent among pregnant women, may be associated with adverse childhood neurodevelopment. However, few studies have examined relations between gestational chemical mixture exposure and children's cognitive abilities. In a cohort of 253 pregnant women and their children from Cincinnati, OH (enrolled 2003–2006), we quantified biomarker concentrations of 43 metals, phthalates, phenols, polybrominated diphenyl ethers, organophosphate and organochlorine pesticides, polychlorinated biphenyls, perfluoroalkyl substances, and environmental tobacco smoke in blood or urine. Using k-means clustering and principal component (PC) analysis, we characterized chemical mixtures among pregnant women. We assessed children's cognitive abilities using the Wechsler Preschool and Primary Scale of Intelligence-III and Wechsler Intelligence Scale for Children-IV at ages 5 and 8 years, respectively. We estimated covariate-adjusted differences in children's cognitive ability scores ]=cross clusters, and with increasing PC scores and individual biomarker concentrations. Geometric mean biomarker concentrations were generally highest, intermediate, and lowest among women in clusters 1, 2, and 3, respectively. Children born to women in clusters 1 and 2 had 5.1 (95% CI: 9.4,-0.8) and 2.0 (95% CI: 5.5, 1,4) lower performance IQ scores compared to children in cluster 3, respectively. PC scores and individual chemical biomarker concentrations were not associated with cognitive abilities. In this cohort, combined prenatal exposure to phenols, certain phthalates, pesticides, and perfluoroalkyl substances was inversely associated with children's cognition, but some individual chemical biomarker concentrations were not. Additional studies should determine if the aggregate impact of these chemicals on cognition is different from their individual effects. • K-means clustering and PCA used to create mixtures of chemical mixture exposure. • Chemical mixtures are inversely associated with children's cognition. • Individual chemical biomarkers in these mixtures were associated with lower IQ. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) are ubiquitous. Previous studies have found associations between PFAS and thyroid hormones in maternal and cord sera, but the results are inconsistent. To further address this research question, we used mixture modeling to assess the associations with individual PFAS, interactions among PFAS chemicals, and the overall mixture. We collected data through the Health Outcomes and Measures of the Environment (HOME) Study, a prospective cohort study that between 2003 and 2006 enrolled 468 pregnant women and their children in the greater Cincinnati, Ohio region. We assessed the associations of maternal serum PFAS concentrations measured during pregnancy with maternal (n = 185) and cord (n = 256) sera thyroid stimulating hormone (TSH), total thyroxine (TT 4), total triiodothyronine (TT 3), free thyroxine (FT 4), and free triiodothyronine (FT 3) using two mixture modeling approaches (Bayesian kernel machine regression (BKMR) and quantile g-computation) and multivariable linear regression. Additional models considered thyroid autoantibodies, other non-PFAS chemicals, and iodine deficiency as potential confounders or effect measure modifiers. PFAS, considered individually or as mixtures, were generally not associated with any thyroid hormones. A doubling of perfluorooctanesulfonic acid (PFOS) had a positive association with cord serum TSH in BKMR models but the 95% Credible Interval included the null (β = 0.09; 95% CrI: −0.08, 0.27). Using BKMR and multivariable models, we found that among children born to mothers with higher thyroid peroxidase antibody (TPOAb), perfluorooctanoic acid (PFOA), PFOS, and perfluorohexanesulfonic acid (PFHxS) were associated with decreased cord FT 4 suggesting modification by maternal TPOAb status. These findings suggest that maternal serum PFAS concentrations measured in the second trimester of pregnancy are not strongly associated with thyroid hormones in maternal and cord sera. Further analyses using robust mixture models in other cohorts are required to corroborate these findings. • Mixture models assessed maternal PFAS with maternal and cord thyroid hormones. • PFAS mixtures were not strongly associated with maternal or cord thyroid hormones. • PFOS had a positive trending association with thyroid stimulating hormone. • Associations between PFAS and thyroid hormones may be modified by TPOAb status. [ABSTRACT FROM AUTHOR]