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BackgroundPhthalate exposure in pregnancy is typically estimated using maternal urinary phthalate metabolite levels. Our aim was to evaluate the association of urinary and placental tissue phthalates, and to explore the role of maternal and pregnancy characteristics that may bias estimates.MethodsFifty pregnancies were selected from the CANDLE Study, recruited from 2006 to 2011 in Tennessee. Linear models were used to estimate associations of urinary phthalates (2nd, 3rd trimesters) and placental tissue phthalates (birth). Potential confounders and modifiers were evaluated in categories: temporality (time between urine and placenta sample), fetal sex, demographics, social advantage, reproductive history, medication use, nutrition and adiposity. Molar and quantile normalized phthalates were calculated to facilitate comparison of placental and urinary levels.ResultsMetabolites detectable in >80% of both urine and placental samples were MEP, MnBP, MBzP, MECPP, MEOHP, MEHHP, and MEHP. MEP was most abundant in urine (geometric mean [GM] 7.00 ×102 nmol/l) and in placental tissue (GM 2.56 ×104 nmol/l). MEHP was the least abundant in urine (GM 5.32 ×101 nmol/l) and second most abundant in placental tissue (2.04 ×104 nmol/l). In aggregate, MEHP differed the most between urine and placenta (2.21 log units), and MEHHP differed the least (0.07 log units). MECPP was positively associated between urine and placenta (regression coefficient: 0.31 95% CI 0.09, 0.53). Other urine-placenta metabolite associations were modified by measures of social advantage, reproductive history, medication use, and adiposity.ConclusionPhthalates were ubiquitous in 50 full-term placental samples, as has already been shown in maternal urine. MEP and MEHP were the most abundant. Measurement and comparison of urinary and placental phthalates can advance knowledge on phthalate toxicity in pregnancy and provide insight into the validity and accuracy of relying on maternal urinary concentrations to estimate placental exposures.Impact statementThis is the first report of correlations/associations of urinary and placental tissue phthalates in human pregnancy. Epidemiologists have relied exclusively on maternal urinary phthalate metabolite concentrations to assess exposures in pregnant women and risk to their fetuses. Even though it has not yet been confirmed empirically, it is widely assumed that urinary concentrations are strongly and positively correlated with placental and fetal levels. Our data suggest that may not be the case, and these associations may vary by phthalate metabolite and associations may be modified by measures of social advantage, reproductive history, medication use, and adiposity.

Background: Latinos living in emerging communities (i.e., nontraditional destinations with a small but growing population) face obstacles to their mental and physical health. This study evaluated the effectiveness of a 6-month, "promotor"-led intervention on access to care, physical activity, dietary practices, and perceived social support among Latino adults living in an emerging community, compared with a nonrandomly assigned control group. Method: Participants (n = 81 intervention; n = 86 control) were drawn from Allegheny county, Pennsylvania. "Promotores" used an intervention tool offering nondirective social support to assist participants in developing SMART goals to address their life concerns in eight domains (e.g., social, diet, and exercise/recreation); the control group received printed materials. Participants completed a survey in Spanish at baseline and follow-up to assess outcomes and had their height and weight measured. Adjusted linear mixed effects models compared change in outcomes over time. Results: There was a marginally significant improvement in dietary practices in the intervention group at follow-up, and no change in access to care. Both groups experienced an improvement in social support. There was a significant intervention-by-time interaction such that the intervention group increased physical activity by 259 minutes/week compared with the control group. Conclusion: This study demonstrates the potential effectiveness of a "promotores" network in assisting individuals living in an emerging Latino community to address their life concerns and improve health behaviors. Future studies should include objective and more rigorous measures with a larger sample to replicate these results.

Carbon-supported platinum-lanthanum (Pt-Ln) intermetallic compound (IMC) nanoparticles with high activity and robust stability have been demonstrated as promising cathode catalysts for proton-exchange membrane fuel cells. However, the preparation of Pt-Ln IMC catalysts needs high-temperature annealing treatment that inevitably causes nanoparticle sintering, resulting in significant reduction of the electrochemical surface area and mass-based activity. Here, we prepare small-sized M-doped Pt5Ce (M = Ga, Cd, and Sb) IMCs catalysts via a low-melting-point metal doping strategy. We speculate that the doping of low-melting-point metals can facilitate the generation of vacancies in the crystal lattice through thermal activation and thus reduce the kinetic barriers for the formation of intermetallic Pt5Ce catalysts. The prepared Ga-doped Pt5Ce catalyst exhibits a higher electrochemical active surface area (81 m2·gPt−1) and a larger mass activity (0.45 A·mgPt−1 at 0.9 V) over the undoped Pt5Ce and commercial Pt/C catalysts. In the membrane electrode assembly test, the Ga-doped Pt5Ce cathode delivers a power density of 0.98 W·cm−2 at 0.67 V, along with a voltage loss of only 27 mV at 0.8 A·cm−2 at the end of accelerated stability test. [ABSTRACT FROM AUTHOR]