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BACKGROUND: Organophosphate esters (OPEs), used ubiquitously as flame retardants and plasticizers in consumer products, are suspected of having developmental toxicity. OBJECTIVES: Our study aimed to estimate associations between prenatal exposure to OPEs and fetal growth, including both ultrasound (head circumference, abdominal circumference, femur length, and estimated fetal weight) and delivery [birth weight z-score, small-for-gestational age (SGA), and large-for-gestational age (LGA)] measures of growth. METHODS: In the LIFECODES Fetal Growth Study (2008-2018), an enriched case--cohort of 900 babies born at the small and large ends of the growth spectrum, we quantified OPE biomarkers in three urine samples per pregnant participant and abstracted ultrasound and delivery measures of fetal growth from medical records. We estimated associations between pregnancy-averaged log-transformed OPE biomarkers and repeated ultrasound measures of fetal growth using linear mixed-effects models, and delivery measures of fetal growth using linear (birth weight) and logistic (SGA and LGA) regression models. RESULTS: Most OPE biomarkers were positively associated with at least one ultrasound measure of fetal growth, but associations with delivery measures were largely null. For example, an interquartile range (IQR; 1.31 ng=mL) increase in bis(2-chloroethyl) phosphate concentration was associated with larger z-scores in head circumference [mean difference (difference): 0.09; 95% confidence interval (CI): 0.01, 0.17], abdominal circumference (difference: 0.10; 95% CI: 0.02, 0.18), femur length (difference: 0.11; 95% CI: 0.03, 0.19), and estimated fetal weight (difference: 0.13; 95% CI: 0.04, 0.22) but not birth weight (difference: 0.04; 95% CI: -0.08, 0.17). At delivery, an IQR (1.00 ng=mL) increase in diphenyl phosphate (DPHP) concentration was associated with an SGA birth (odds ratio: 1.46; 95% CI: 1.10, 1.94). CONCLUSIONS: In a large prospective cohort, gestational OPE exposures were associated with larger fetal size during pregnancy, but associations at delivery were null. DPHP concentrations were associated with heightened risk of an SGA birth. These findings suggest that OPE exposure may affect fetal development. https://doi.org/10.1289/EHP14647, Introduction Organophosphate esters (OPEs) are high-production chemicals in widespread global use. (1) They are organic esters of phosphoric acid--containing alkyl chains or aryl groups, which may be halo-genated or nonhalogenated. [...]

BACKGROUND: Glyphosate is one of the most heavily used pesticides in the world, but little is known about sources of glyphosate exposure in pregnant people living in agricultural regions. OBJECTIVE: Our objective was to evaluate glyphosate exposure during pregnancy in relation to residential proximity to agriculture as well as agricultural spray season. METHODS: We quantified glyphosate concentrations in 453 urine samples collected biweekly from a cohort of 40 pregnant people in southern Idaho from February through December 2021. We estimated each participants glyphosate exposure as the geometric mean (GM) of glyphosate concentrations measured in all samples (average n=11 samples/participant), as well as the GM of samples collected during the pesticide spray season (defined as those collected 1 May-15 August; average n=5 samples/participant) and the nonspray season (defined as those collected before 1 May or after 15 August; average n=6 samples/participant). We defined participants who resided

BackgroundConsumption of an organic diet reduces exposure to a range of agricultural pesticides. Only three studies have examined the effect of an organic diet intervention on exposure to the herbicide glyphosate, the most heavily used agricultural chemical in the world. Despite its widespread use, the primary sources of glyphosate exposure in humans are poorly understood.ObjectiveOur objective was to examine the effect of an organic diet intervention on urinary glyphosate concentrations among pregnant individuals.MethodsWe conducted a 2-wk randomized crossover trial in which 39 pregnant participants living near (≤0.5km) and far (>0.5km) from agricultural fields received a 1-wk supply of conventional groceries and 1 wk of organic groceries, randomized to order. We collected daily first morning void urine samples and analyzed composite samples from each week for glyphosate. We examined differences in urinary glyphosate concentrations between the conventional week and the organic week among all participants and stratified by residential proximity to an agricultural field.ResultsMedian specific gravity-adjusted glyphosate concentrations were 0.19μg/L and 0.16μg/L during the conventional and organic weeks, respectively. We observed modest decreases in urinary glyphosate concentrations from the conventional to organic week among far-field participants, but no difference among near-field participants. In secondary analyses excluding participants who did not meet a priori criteria of compliance with the intervention, we observed significant decreases in urinary glyphosate concentrations, particularly among far-field participants (p0.5km from agricultural fields; for people living near crops, agriculture may be a dominant exposure source during the pesticide spray season. https://doi.org/10.1289/EHP12155.

Maleic anhydride-grafted-polyethylene was dynamically cross-linked via reactive melt blending with 4,4'-dithiodianiline. Thermal and mechanical properties of polyethylene vitrimers with different cross-linking density were investigated. The results indicate that the degree of crystallinity decreased with increasing cross-linking density. This behavior was directly related to short-term and long-term mechanical properties: vitrimers showed a decrease in yield strength and creep performance. The yield strength of PE vitrimers decreased linearly in relation to the degree of crystallinity. Polarized optical microscopy revealed that the cross-links inhibit the growth of spherulites structure in polyethylene vitrimers. Thermogravimetric analysis indicated an increase in the onset degradation temperature and decomposition rate for vitrimers with increased cross-linking density. The stiffness of the vitrimers decreased with increasing cross-linking density which led to higher damping properties. Finally, it was demonstrated that reprocessing of polyethylene vitrimer was possible without significant impact in mechanical properties. KEYWORDS cross-linking, mechanical properties, polyethylene, reprocessing, structure-property relations, thermal properties, vitrimers, 1 | INTRODUCTION Polyethylene (PE) is presently the most-used commodity plastic by volume and it is frequently used in consumer goods, construction, and electrical industry. [1,2] Some examples include plastic [...]

Background: The consumption of foods such as sweet potato and cassava with high levels of carotenoids is a possible solution to reduce vitamin A deficiency. In this study, we evaluated the kinetics of thermal degradation of carotenoids. The content of carotenoids was quantified by high‐performance liquid chromatography, first in fresh material, then in flour and finally in bakery products using mixtures of wheat, sweet potato and cassava. The degree of acceptance of the bakery products by children was also assessed through a sensory acceptance test. Results: The study found that the degradation of carotenoid compounds in sweet potato followed first‐order kinetics and fitted the Arrhenius equation with correlations of R2 > 0.9. The retention rates of all‐trans‐β‐carotene were 77%, 56% and 48% at cooking temperatures of 75, 85 and 95 °C respectively, during a cooking time of 20 min. The concentrations of all‐trans‐β‐carotene, after baking, for bread, cookies and cake were 15, 19 and 14 μg g−1 db, respectively. In a sensory acceptance test carried out in a school, 47.6% of the boys and 79.2% of the girls rated the cookies made from a mixture of cassava, sweet potato and wheat flour with the indicator I like it a lot. Conclusion: The content of carotenoid compounds was reduced by exposure to high temperatures and long cooking times. The combinations of cooking time and temperature which minimized degradation of all‐trans‐β‐carotene occurred at 75 °C–20 min and 95 °C–10 min. All‐trans‐β‐carotene retentions for bread, cookies and cake were 25%, 15% and 11% respectively. The mixture of wheat, sweet potato and cassava flour can be considered in the development of cookies with positive contributions of all‐trans‐β‐carotenes and with a good acceptance by children between 9 and 13 years old. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: The purpose of this study was to investigate the potential of hyperspectral imaging for the characterization of cooking quality parameters, dry matter content (DMC), water absorption (WAB), and texture in cassava genotypes contrasting for their cooking quality. RESULTS: Hyperspectral images were acquired on cooked and fresh intact longitudinal and transversal slices from 31 cassava genotypes harvested in March 2022 in Colombia. Different chemometric methods were tested for the quantification of DMC, WAB, and texture parameters. Data analysis was conducted through partial least squares regression, K nearest neighbors regression, support vector machine regression and CovSel multiple linear regression (CovSel_MLR). Efficient performances were obtained for DMC using CovSel_MLR with, coefficient of multiple determination Rp2=0.94, root‐mean‐square error of prediction RMSEP = 0.96 g/100 g, and ratio of the standard deviation values RPD = 3.60. High heterogeneity was observed between contrasting genotypes. The predicted distribution of DMC within the root can be homogeneous or heterogeneous depending on the genotype. Weak predictions were obtained for WAB and texture parameters. CONCLUSIONS: This study showed that hyperspectral imaging could be used as a high‐throughput phenotyping tool for the visualization of DMC in contrasting cooking quality genotypes. Further improvement of protocols and larger datasets are required for WAB and texture quality traits. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Objectives: To describe screen time levels and determine their association with socioemotional and behavioural difficulties among preschool-aged First Nations, Métis, and Inuit children. Method: Data were taken from the Aboriginal Children's Survey, a nationally representative survey of 2–5-year-old Indigenous children in Canada. Socioemotional and behavioural difficulties were defined using parent/guardian reports on the Strengths and Difficulties Questionnaire. Multiple linear regression analyses were conducted separately for First Nations, Métis, and Inuit participants, and statistically adjusted for child age, child sex, and parent/guardian education. Statistical significance was set at P < 0.002 to adjust for multiple comparisons. Results: Of these 2–5-year-old children (mean [ M ] = 3.57 years) 3,085 were First Nations (53.5%), 2,430 Métis (39.2%), and 990 Inuit (7.3%). Screen time exposure was high among First Nations (M = 2 h and 58 min/day, standard deviation [ SD ] = 1.89), Métis (M = 2 h and 50 min [ SD = 1.83]), and Inuit children (M = 3 h and 25 min [ SD = 2.20]), with 79.7% exceeding recommended guidelines (>1 h/day). After adjusting for confounders, screen time was associated with more socioemotional and behavioural difficulties among First Nations (total difficulties β = 0.15 [95% CI, 0.12 to 0.19]) and Métis (β = 0.16 [95% CI, 0.12 to 0.20]) but not Inuit children (β = 0.12 [95% CI, 0.01 to 0.23]). Conclusions: Screen time exposure is high among Indigenous children in Canada, and is associated with more socioemotional and behavioural difficulties among First Nations and Métis children. Contributing factors could include enduring colonialism that resulted in family dissolution, lack of positive parental role models, and disproportionate socioeconomic disadvantage. Predictors of poor well-being should continue to be identified to develop targets for intervention to optimize the health and development of Indigenous children. [ABSTRACT FROM AUTHOR]