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7. Potassium jarosite seeding of soils decreases lead and arsenic bioaccessibility: A path toward concomitant remediation.

Author

Sowers, Tyler D., Blackmon, Matthew D., Betts, Aaron R., Jerden, Marissa L., Scheckel, Kirk G., and Bradham, Karen D.

Subjects
JAROSITE, LEAD in soils, HAZARDOUS waste sites, ARSENIC, SOIL remediation
Abstract

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]

Published
2023
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13. A national survey of lead and other metal(loids) in residential drinking water in the United States

Author

Bradham, Karen D., primary, Nelson, Clay M., additional, Sowers, Tyler D., additional, Lytle, Darren A., additional, Tully, Jennifer, additional, Schock, Michael R., additional, Li, Kevin, additional, Blackmon, Matthew D., additional, Kovalcik, Kasey, additional, Cox, David, additional, Dewalt, Gary, additional, Friedman, Warren, additional, Pinzer, Eugene A., additional, and Ashley, Peter J., additional

Published
2022
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23. Interconnected soil iron and arsenic speciation effects on arsenic bioaccessibility and bioavailability: a scoping review.

Author

Sowers, Tyler D., Nelson, Clay M., Blackmon, Matthew D., Jerden, Marissa L., Kirby, Alicia M., Diamond, Gary L., and Bradham, Karen D.

Subjects
ARSENIC, SOIL composition, CHEMICAL speciation, BIOAVAILABILITY, PRECIPITATION (Chemistry), SOILS
Abstract

Extensive research has examined arsenic (As) bioavailability in contaminated soils and is routinely assessed using in vitro bioaccessibility (IVBA) assays. Analysis of differences in bioaccessibility measurements across IVBA assays and phases is expected to provide valuable insights into geochemical mechanisms controlling soil As bioaccessibility and bioavailability. Soil iron (Fe) content and As speciation are expected to significantly influence IVBA gastric and intestinal phases due to fluctuations in precipitation-dissolution chemistry and sorption reactivity as pH and assay chemical complexity changes. The aim of this review was to examine these relationships by 1) conducting a meta-analysis (n = 47 soils) determining the influence of total Fe on As bioaccessibility measurements and 5 IVBA assays and 2) investigating the effect of As speciation on gastric/intestinal phase IVBA and in vitro-in vivo correlations. Our findings indicate that soil Fe content and As speciation heterogeneity are important in elucidating variability of bioaccessibility measurements across IVBA assays and gastrointestinal phases. Greater focus on coupled As speciation and Fe precipitation chemistry may (1) improve our understanding of soil geochemical factors and assay constituents that influence As in vitro-in vivo correlations and (2) resolve variability in the precision of oral relative bioavailability (RBA) estimated using IVBA assays for soils possessing heterogenous As speciation and Fe composition. [ABSTRACT FROM AUTHOR]

Published
2022
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24. Arsenic and environmental health: state of the science and future research opportunities

Author

Carlin, Danielle J., Naujokas, Marisa F., Bradham, Karen D., Cowden, John, Heacock, Michelle, Henry, Heather F., Lee, Janice S., Thomas, David J., Thompson, Claudia, Tokar, Erik J., Waalkes, Michael P., Birnbaum, Linda S., and Suk, William A.

Subjects
Arsenic -- Health aspects, Medical research, Environmental health -- Research, Public health administration -- Forecasts and trends, Market trend/market analysis, Environmental issues, Health
Abstract

BACKGROUND: Exposure to inorganic and organic arsenic compounds is a major public health problem that affects hundreds of millions of people worldwide. Exposure to arsenic is associated with cancer and noncancer effects in nearly every organ in the body, and evidence is mounting for health effects at lower levels of arsenic exposure than previously thought. Building from a tremendous knowledge base with > 1,000 scientific papers published annually with 'arsenic' in the title, the question becomes, what questions would best drive future research directions? OBJECTIVES: The objective is to discuss emerging issues in arsenic research and identify data gaps across disciplines. METHODS: The National Institutes of Health's National Institute of Environmental Health Sciences Superfund Research Program convened a workshop to identify emerging issues and research needs to address the multi-faceted challenges related to arsenic and environmental health. This review summarizes information captured during the workshop. DISCUSSION: More information about aggregate exposure to arsenic is needed, including the amount and forms of arsenic found in foods. New strategies for mitigating arsenic exposures and related health effects range from engineered filtering systems to phytogenetics and nutritional interventions. Furthermore, integration of omics data with mechanistic and epidemiological data is a key step toward the goal of linking biomarkers of exposure and susceptibility to disease mechanisms and outcomes. CONCLUSIONS: Promising research strategies and technologies for arsenic exposure and adverse health effect mitigation are being pursued, and future research is moving toward deeper collaborations and integration of information across disciplines to address data gaps. http://dx.doi.org/10.1289/ehp.1510209, INTRODUCTION Inorganic and organic arsenic compounds continue to pose environmental public health challenges for hundreds of millions of people worldwide (WHO 2008). Nearly every organ in the body can be [...]

Published
2016
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30. Characterization of engineered nanoparticles in commercially available spray disinfectant products advertised to contain colloidal silver

Author

Rogers, Kim R., primary, Navratilova, Jana, additional, Stefaniak, Aleksandr, additional, Bowers, Lauren, additional, Knepp, Alycia K., additional, Al-Abed, Souhail R., additional, Potter, Phillip, additional, Gitipour, Alireza, additional, Radwan, Islam, additional, Nelson, Clay, additional, and Bradham, Karen D., additional

Published
2018
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36. Predicting oral relative bioavailability of arsenic in soil from in vitro bioaccessibility

Author

Diamond, Gary L., primary, Bradham, Karen D., additional, Brattin, William J., additional, Burgess, Michele, additional, Griffin, Susan, additional, Hawkins, Cheryl A., additional, Juhasz, Albert L., additional, Klotzbach, Julie M., additional, Nelson, Clay, additional, Lowney, Yvette W., additional, Scheckel, Kirk G., additional, and Thomas, David J., additional

Published
2016
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47. Assessing the Bioavailability and Risk from Metal-Contaminated Soils and Dusts.

Author

Bradham, Karen D., Laird, Brian D., Rasmussen, Pat E., Schoof, Rosalind A., Serda, Sophia M., Siciliano, Steven D., and Hughes, Michael F.

Subjects
*HEALTH risk assessment, *SOIL composition, *DUST, *BIOAVAILABILITY, *POLLUTANTS
Abstract

Exposure to contaminated soil and dust is an important pathway in human health risk assessment. Physical and chemical characteristics and biological factors determine the bioaccessibility/bioavailability of soil and dust contaminants. Within a single sample, contamination may arise from multiple sources of toxic elements that may exist as different species that impact bioavailability. In turn, the bioaccessibility/bioavailability of soil and dust contaminants directly impacts human health risk. Research efforts focusing on development and application ofin vitroandin vivomethods to measure the bioaccessibility/bioavailability of metal-contaminated soils have advanced in recent years. The objective of this workshop was to focus on developments in assessing the bioaccessibility/bioavailability of arsenic-contaminated soils, metals’ contamination in urban Canadian residences and potential children's exposures to toxic elements in house dust, an urban community-based study (i.e., West Oakland Residential Lead Assessment), bioavailability studies of soil cadmium, chromium, nickel, and mercury and human exposures to contaminated Brownfield soils. These presentations covered issues related to human health and bioavailability along with the most recent studies on community participation in assessing metals’ contamination, studies of exposures to residential contamination, andin vitroandin vivomethods development for assessing the bioaccessibility/bioavailability of metals in soils and dusts. [ABSTRACT FROM AUTHOR]

Published
2014
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49. Opportunities and challenges associated with bioavailability-based remediation strategies for lead-contaminated soil with arsenic as a co-contaminant-a critical review

Author

Farzana Kastury, Hongbo Li, Ranju Karna, Aaron Betts, Kirk G. Scheckel, Lena Q. Ma, Tyler D. Sowers, Karen D. Bradham, Ganga M. Hettiarachchi, Albert L. Juhasz, Kastury, Farzana, Li, Hongbo, Karna, Ranju, Betts, Aaron, Scheckel, Kirk G, Ma, Lena Q, Sowers, Tyler D, Bradham, Karen D, Hettiarachchi, Ganga M, and Juhasz, Albert L

Subjects
speciation, immobilization, treatment effect ratio, Management, Monitoring, Policy and Law, bioavailability, Pollution, Waste Management and Disposal, bioaccessibility, metal contamination, Water Science and Technology
Abstract

Purpose of Review The ubiquity of soil contamination by lead (Pb) and arsenic (As) has prompted the development of numerous techniques for its remediation. For human health exposure assessment, oral bioavailability-based methods are the most suitable to assess the efficacy of these treatment strategies, including in vivo relative bioavailability (systemic absorption relative to a toxicity reference) and in vitro bioaccessibility (dissolution in simulated gastrointestinal solutions). This paper provides a critical review of opportunities and challenges associated with the immobilization of Pb and As in contaminated soil. Recent Findings This review identified that the major inorganic and organic amendments used to reduce Pb and As exposure include phosphate, industrial by-products, metal oxides, organic matter, biochar, and treatment with iron sulphate to promote the formation of plumbojarosite in soil. In addition to RBA and IVBA assessment, investigating changes in Pb/As speciation in untreated vs treated soil can provide additional confirmation of treatment efficacy. The results of this review showed that immobilization efficacy may vary depending on amendment type, Pb, and As speciation in soil and the approach used for its assessment. Summary Reducing childhood exposure to Pb and As is a significant challenge, given the variety of contamination sources and treatment strategies. A lines-of-evidence approach using standardized methodologies is recommended for the assessment of immobilization efficacy to ensure exposure and risk reduction Graphical Abstract Bioavailability-based remediation strategies. Popular soil amendments to reduce Pb exposure include phosphate, industrial by-products, metal oxides, organic matter, and biochar; however, these may increase As exposure. The plumbojarosite formation technique has been recently developed to mitigate Pb and As exposure simultaneously. Multiple lines-of-evidence approach is recommended to assess treatment efficacy

Published
2023

50. Plumbojarosite Remediation of Soil Affects Lead Speciation and Elemental Interactions in Soil and in Mice Tissues

Author

Karen D. Bradham, Ranju R. Karna, Gary Diamond, Tyler D. Sowers, David J. Thomas, Sharon E. Bone, Matthew R. Noerpel, Kirk G. Scheckel, Albert L. Juhasz, Matthew D. Blackmon, Sowers, Tyler D, Bone, Sharon E, Noerpel, Matthew R, Blackmon, Matthew D, Karna, Ranju R, Scheckel, Kirk G, Juhasz, Albert L, Diamond, Gary L, Thomas, David J, and Bradham, Karen D

Subjects
PLJ, Environmental remediation, media_common.quotation_subject, Biological Availability, RBA, Article, Mice, Soil, Environmental Chemistry, Ingestion, Animals, Soil Pollutants, media_common, Contaminated soils, Chemistry, lead bioavailability, General Chemistry, Contamination, Soil contamination, XANES, Bioavailability, Speciation, μ-XRF, X-Ray Absorption Spectroscopy, speciation, Environmental chemistry, Soil water, gastrointestinal tract, Environmental Pollution
Abstract

Refereed/Peer-reviewed Lead (Pb) contamination of soils is of global concern due to the devastating impacts of Pb exposure in children. Because early-life exposure to Pb has long-lasting health effects, reducing exposure in children is a critical public health goal that has intensified research on the conversion of soil Pb to low bioavailability phases. Recently, plumbojarosite (PLJ) conversion of highly available soil Pb was found to decrease Pb relative bioavailability (RBA

Published
2021

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