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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 [...]

Few studies have focused on off‐reserve Indigenous children and families. This nationally representative, cross‐sectional study (data collected from 2006 to 2007) examined Indigenous‐ and non‐Indigenous‐specific determinants associated with positive socioemotional and behavioral well‐being among First Nations children living off‐reserve in Canada. The parents or other caregivers of 2990 two‐to‐five‐year‐old children (M = 3.65; 50.6% male) reported on their children's socioemotional and behavioral well‐being and a range of child, parent, and housing characteristics. Being taught an Indigenous culture, greater community cohesion, caregiver nurturance, good parental/other caregiver health, and fewer household members were associated with better socioemotional and behavioral well‐being. These results highlight the importance of leveraging Indigenous‐specific determinants and acknowledging non‐Indigenous‐specific factors, to promote the well‐being of First Nations children living off‐reserve. [ABSTRACT FROM AUTHOR]

Biofortified cassava (Manihot esculenta) plays a crucial role in enhancing the nutritional value of this essential staple, particularly in regions with limited dietary diversity and prevalent nutritional deficiencies. The cassava program at the International Center of Tropical Agriculture has dedicated over a decade to increase β‐carotene content in biofortified cassava, simultaneously focusing on improving yield, dry matter, and plant architecture. This paper presents realized genetic gains in biofortified cassava by analyzing the data from replicated multilocation breeding yield trials at the target population of environments spanning a 10‐year period (2013–2022). Following data curation, we observed significant positive genetic gains per year for β‐carotene content (7.03%), fresh yield (4.15%), dry matter content (0.55%), and height at the first branch (1.29%). A negative correlation between β‐carotene content and dry matter content was observed within 78% of trials. Moreover, our study uncovered a significant negative correlation between β‐carotene content and fresh root yield (r = −0.22, p < 0.01) and an unfavorable positive correlation between β‐carotene content and the number of branches (r = 0.23, p < 0.01). Such negative correlations between β‐carotene content and farm‐preferred traits presented substantial challenges for the development of biofortified cassava varieties. This research showed significant genetic gains and navigated the complexities of biofortified cassava development, providing breeding insights to enhance nutritional value while optimizing agronomic performance. Core Ideas: The biofortified cassava population was simultaneously improved over a decade for quality and agronomic traits.Significant rates of genetic gains were achieved in β‐carotene content, yield, dry matter, and plant architecture.Negative correlations were observed between β‐carotene content and dry matter, as well as fresh root yield.The observed trade‐offs present substantial challenges in developing biofortified cassava cultivars. Plain Language Summary: Biofortification, the method of increasing nutrient levels in crops through selective breeding, can help alleviate global hidden hunger or micronutrient deficiencies. Researchers have biofortified cassava (Manihot esculenta), a food staple for millions in the tropics, by increasing the β‐carotene (provitamin A) content in roots. This involved years of careful selection and testing of cassava plants with high β‐carotene, high yield, and optimal plant characteristics. Researchers monitor this process by calculating what is known as genetic gain, an indicator of the change or improvement of cassava traits over time. Substantial genetic gains have been achieved in β‐carotene content, yield, and plant type over a decade. Yet, gains in nutritional quality (high β‐carotene content) sometimes come at the expense of sacrificing other desirable traits like high yield. Overcoming these trade‐offs is crucial for developing new cassava varieties that excel in all desirable traits. [ABSTRACT FROM AUTHOR]

Background: Breast and cervical cancers pose significant health challenges for women globally, emphasizing the critical importance of effective screening programs for early detection. In Canada, despite the implementation of accessible healthcare systems, ethnic and racialized disparities in cancer screening persist. This study aims to assess ethnic and racialized disparities in breast and cervical cancer screening in Canada. Methods: Using 2015–2019 data from the Canadian Community Health Survey, we analyzed women aged 18–70 in distinct ethnic and racial groups. The primary outcome was mammography or Papanicolaou test (pap smear). The secondary outcome was time since the last screening. We used weighted multivariable logistic regression to estimate the odds of having a pap smear or mammography across the ethnic and racialized groups, adjusted for relevant covariates. Results were reported as odds ratios (ORs) with 95% confidence intervals (CIs). Results: We included 14,628,067 women of which 72.5% were White, 8.4% Southeast Asian, 4.7% South Asian, 3.4% Indigenous, 2.7% Black, 2.0% West Asian, and 1.6% Latin American. In comparison with the White reference group, a higher odds ratio of not having a pap smear was estimated for the West Asian (5.63; CI 3.85, 8.23), South Asian (5.19; CI 3.79, 7.12), Southeast Asian (4.35; CI 3.46, 5.46), and Black groups (2.62; CI 1.82, 3.78). Disparities in mammography screening were found only for the Southeast Asian group with higher odds of not having screening (1.85; CI 1.15, 2.98) compared to the White reference group. Conclusion: This study reveals significant disparities in pap smear and mammography screenings affecting various ethnic groups, particularly in West Asia, South Asian, and Black communities. These findings underscore the urgent need for targeted interventions, policies, and healthcare strategies to address these gaps and ensure equitable access to essential breast and cervical cancer prevention across all ethnicity. [ABSTRACT FROM AUTHOR]