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Measuring the reduction of in vitro bioaccessible (IVBA) Pb from the addition of phosphate amendments has been researched for more than 20 years. A range of effects have been observed from increases in IVBA Pb to almost 100% reduction. This study determined the mean change in IVBA Pb as a fraction of total Pb (AC) and relative to the IVBA Pb of the control soil (RC) with a random effects meta-analysis. Forty-four studies that investigated the ability of inorganic phosphate amendments to reduce IVBA Pb were identified through 5 databases. These studies were split into 3 groups: primary, secondary, and EPA Method 1340 based on selection criteria, with the primary group being utilized for subgroup analysis and meta-regression. The mean AC was approximately -12% and mean RC was approximately -25% for the primary and secondary groups. For the EPA Method 1340 group, the mean AC was -5% and mean RC was -8%. The results of subgroup analysis identified the phosphorous amendment applied and contamination source as having a significant effect on the AC and RC. Soluble amendments reduce bioaccessible Pb more than insoluble amendments and phosphoric acid is more effective than other phosphate amendments. Urban Pb contamination associated with legacy Pb-paint and tetraethyl Pb from gasoline showed lower reductions than other sources such as shooting ranges and smelting operations. Meta-regression identified high IVBA Pb in the control, low incubated soil pH, and high total Pb with the greater reductions in AC and RC. In order to facilitate comparisons across future remediation research, a set of minimum reported data should be included in published studies and researchers should use standardized in vitro bioaccessibility methods developed for P-treated soils. Additionally, a shared data repository should be created for soil remediation research to enhance available soil property information and better identify unique materials.

Cadmium contamination in waters and soils can lead to food chain accumulation and ultimately deterioration in human health; means for reducing bioavailable Cd are desperately required, and biochars may play a role. Long-term (240 d) lab incubation experiments were utilized to explain wheat straw-derived biochar effects on Cd sorption and decreasing Cd bioavailability in soils and solutions (0, 5, and 15% biochar as wt:wt or wt:vol, respectively), and to identify Cd forms present using both the European Community Bureau of Reference (BCR) chemical sequential extraction procedure and synchrotron-based X-ray absorption spectroscopy (XAS). Biochar Cd removal was up to ~90% from Cd-containing solutions and contaminated soil as compared to the control. Based on the wet chemical sequential extraction procedure in conjunction with XAS, biochar application promoted the formation of (oxy)hydroxide, carbonate, and organically bound Cd phases. As a material, biochar may be promoted as a tool for reducing and removing bioavailable Cd from contaminated waters and soils. Thus, biochar may play a role in reducing Cd bioaccumulation, trophic transfer, and improving environmental quality and human health. Keywords: BCR method, Biochar (BC), Cadmium, Contaminated paddy soil, Synchrotron, X-ray absorption spectroscopy

Sinus of Valsalva aneurysm, dilatation of one or more of the aortic sinuses, is a rare but important aortic root defect, which can be a cause of some serious cardiac sequels. The purpose of this article is to review the etiopathogenesis, relevant anatomy, clinical manifestations, potential complications, multimodality imaging features, and management of this rare but important entity of sinus of Valsalva.

In this study, an in vitro in vivo correlation (IVIVC) between Pb in vitro bioaccessibility (IVBA) and relative bioavailability (RBA) was explored to determine whether the efficacy of Pb immobilization in phosphate amended soils could be predicted using an in vitro approach. Mining/smelting impacted soil from Broken Hill, Australia (582–3536 mg/kg of Pb in the 1000 mg/kg Pb while treatment effect ratios of 0.89–0.99 (SBRC-G), 0.09–0.71 (SBRC-I) and 0.27–0.80 (RBA) were observed in PA amended soil (Pb:P = 1:5). Although significant (p

The Cardium Formation “halo oil” occurs either in the fringe of, or between, existing conventional discrete sandstone reservoirs. It is commonly associated with conventional oil and gas pools in stratigraphic traps. This paper uses a geological model-based simulation approach to assess Cardium “halo oil” resource potential. The geological model-based approach consists of a geological model, a resource model and a stochastic modeling procedure that extracts essential information regarding the richness and spatial characteristics of oil resources from various data sources using statistical methods. It integrates them with the geological and resource models, respectively, to estimate the resource potential. This approach predicts not only the resource potential, but also the resource spatial distribution and the exploration risk. These outcomes provide critical information for exploration decision-making. Cardium “halo-oil” assessment results indicate a mean total oil in-place (conventional and unconventional) of 4.6×109 m3 and a mean undiscovered “halo oil” in-place of 2.9×109 m3. Using current technology and economic constraints the undiscovered recoverable “halo oil” in this tight formation is 0.11×109 m3. This represents

BackgroundData from the COVID-19 pandemic describes increases in drug use and related harms, especially fatal overdose. However, evidence is needed to better understand the pathways from pandemic-related factors to substance use behaviours. Thus, we investigated stockpiling drugs among people who use drugs (PWUD) in five cities in the United States and Canada.MethodsWe used data from two waves of interviews among participants in nine prospective cohorts to estimate the prevalence and correlates of stockpiling drugs in the previous month. Longitudinal correlates were identified using bivariate and multivariate generalized linear mixed-effects modeling analyses.ResultsFrom May 2020 to February 2021, we recruited 1873 individuals who completed 2242 interviews, of whom 217 (11.6%) reported stockpiling drugs in the last month at baseline. In the multivariate model, stockpiling drugs was significantly and positively associated with reporting being greatly impacted by COVID-19 (Adjusted Odds Ratio [AOR]= 1.21, 95% CI: 1.09-1.45), and at least daily use of methamphetamine (AOR = 4.67, 95% CI: 2.75-7.94) in the past month.ConclusionsWe observed that approximately one-in-ten participants reported stocking up on drugs during the COVID-19 pandemic. This behaviour was associated with important drug-related risk factors including high-intensity methamphetamine use. While these correlations need further inquiry, it is possible that addressing the impact of COVID-19 on vulnerable PWUD could help limit drug stockpiling, which may lower rates of high-intensity stimulant use.

Broadening participation in engineering is an important national priority and has led to increasing demands for engineering content to be integrated into traditional K-12 curriculum. However, expecting teachers to incorporate engineering into their classrooms without additional training or resources is unreasonable. Partnering teachers with industry partners is one promising way to prioritize integrated science and engineering content while also introducing youth to possible career paths. In this programmatic article, we introduce the Partnering with Educators and Engineers in Rural Schools (PEERS) project that focuses on the collaborative design, implementation, and study of recurrent hands-on engineering activities with middle school youth in three rural communities in or near Appalachia. We discuss the curricular priorities of the program as well as preliminary findings on both student-focused and capacity-building metrics across the partnerships. Key discussion points include (1) a need to distill goals for engineering outreach by wrestling with what success might really look like for middle-school youth engagement with engineering and (2) cultivating community capacity to better support education systems and the simultaneous potential for and challenges of collaborating to build such infrastructure.

The in situ sequestration of lead (Pb) in sediment with a phosphate amendment was investigated by Pb speciation and bioavailability. Sediment Pb in preamendment samples was identified as galena (PbS) with trace amounts of absorbed Pb. Sediment exposed to atmospheric conditions underwent conversion to hydrocerussite and anglesite. Sediments mixed with apatite exhibited limited conversion to pyromorphite, the hypothesized end product. Conversion of PbS to pyromorphite is inhibited under reducing conditions, and pyromorphite formation appears limited to reaction with pore water Pb and PbS oxidation products. Porewater Pb values were decreased by 94% or more when sediment was amended with apatite. The acute toxicity of the sediment Pb was evaluated with Hyalella azteca and bioaccumulation of Pb with Lumbriculus variegatus. The growth of H. azteca may be mildly inhibited in contaminated sediment, with apatite-amended sediments exhibiting on average a higher growth weight by approximately 20%. The bioaccumulation of Pb in L. variegatus tissue decreased with increased phosphate loading in contaminated sediment. The study indicates limited effectiveness of apatite in sequestering Pb if present as PbS under reducing conditions, but sequestration of porewater Pb and stabilization of near-surface sediment may be a feasible and alternative approach to decreasing potential toxicity of Pb.

Background: Emerging evidence suggests social, health, environmental, and economic benefits of urban agriculture (UA). However, limited work has characterized the risks from metal contaminant exposures faced by urban growers and consumers of urban-grown produce. Objectives: We aimed to answer community-driven questions about the safety of UA and the consumption of urban-grown produce by measuring concentrations of nine metals in the soil, irrigation water, and urban-grown produce across urban farms and gardens in Baltimore, Maryland. Methods: We measured concentrations of 6 nonessential [arsenic (As), barium (Ba), cadmium (Cd), chromium (Cr), lead (Pb), nickel (Ni)] and three essential [copper (Cu), manganese (Mn), zinc (Zn)] metals in soil, irrigation water, and 13 types of urban-grown produce collected from 104 UA sites. We compared measured concentrations to existing public health guidelines and analyzed relationships between urban soil and produce concentrations. In the absence of guidelines for metals in produce, we compared metals concentrations in urban-grown produce with those in produce purchased from farmers markets and grocery stores (both conventionally grown and U.S. Department of Agriculture-certified organic). Results: Mean concentrations of all measured metals in irrigation water were below public health guidelines. Mean concentrations of nonessential metals in growing area soils were below public health guidelines for Ba, Cd, Pb, and Ni and at or below background for As and Cr. Though we observed a few statistically significant differences in concentrations between urban and nonurban produce items for some combinations, no consistent or discernable patterns emerged. Discussion: Screening soils for heavy metals is a critical best practice for urban growers. Given limitations in existing public health guidelines for metals in soil, irrigation water, and produce, additional exposure assessment is necessary to quantify potential human health risks associated with exposure to nonessential metals when engaging in UA and consuming urban-grown produce. Conversely, the potential health benefits of consuming essential metals in urban-grown produce also merit further research. https://doi.org/10.1289/EHP9431, Introduction Urban agriculture (UA), which includes growing food for human consumption, fiber, plant-based dyes, and other crops, and in some cases, raising livestock and bees, is increasing in popularity worldwide [...]

Soils are common sources of metal(loid) contaminant exposure globally. Lead (Pb) and arsenic (As) are of paramount concern due to detrimental neurological and carcinogenic health effects, respectively. Pb and/or As contaminated soils require remediation, typically leading to excavation, a costly and environmentally damaging practice of removing soil to a central location (e.g., hazardous landfill) that may not be a viable option in low-income countries. Chemical remediation techniques may allow for in situ conversion of soil contaminants to phases that are not easily mobilized upon ingestion; however, effective chemical remediation options are limited. Here, we have successfully tested a soil remediation technology using potted soils that relies on converting soil Pb and As into jarosite-group minerals, such as plumbojarosite (PLJ) and beudantite, possessing exceptionally low bioaccessibility [i.e., solubility at gastric pH conditions (pH 1.5 to 3)]. Across all experiments conducted, all new treatment methods successfully promoted PLJ and/or beudantite conversion, resulting in a proportional decrease in Pb and As bioaccessibility. Increasing temperature resulted in increased conversion to jarosite-group minerals, but addition of potassium (K) jarosite was most critical to Pb and As bioaccessibility decreases. Our methods of K-jarosite treatment yielded <10% Pb and As bioaccessibility compared to unamended soil values of approximately 70% and 60%, respectively. The proposed treatment is a rare dual remediation option that effectively treats soil Pb and As such that potential exposure is considerably reduced. Research presented here lays the foundation for ongoing field application. [ABSTRACT FROM AUTHOR]