Mapping the Urban Lead Exposome: A Detailed Analysis of Soil Metal Concentrations at the Household Scale Using Citizen Science

Associations among neighborhood walkability, metal exposure, and sex steroid hormone levels: Results from Hangzhou Birth Cohort Study Ⅱ

BACKGROUND

Neighborhood walkability may influence maternal-fetal exposure to environmental hazards and maternal-fetal health (e.g., fetal growth restriction, reproductive toxicity). However, few studies have explored the association between neighborhood walkability and hormones in pregnant women.

METHODS

We included 533 pregnant women from the Hangzhou Birth Cohort Study II (HBCS-II) with testosterone (TTE) and estradiol (E2) measured for analysis. Neighborhood walkability was evaluated by calculating a walkability index based on geo-coded addresses. Placental metals were measured using inductively coupled plasma mass spectrometry (ICP-MS). TTE and E2 levels in umbilical cord blood were measured using chemiluminescence microparticle immunoassay (CMIA). Linear regression model was used to estimate the relationship between the walkability index, placental metals, and sex steroid hormones. Effect modification was also assessed to estimate the effect of placental metals on the associations of neighborhood walkability with TTE and E2.

RESULTS

Neighborhood walkability was significantly linked to increased E2 levels (P trend=0.023). Compared with participants at the first quintile (Q1) of walkability index, those at the third quintiles (Q3) had lower chromium (Cr) levels (β = -0.212, 95% CI = -0.421 to -0.003). Arsenic (As), cobalt (Co), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), antimony (Sb), selenium (Se), tin (Sn), and vanadium (V) were linked to decreased TTE levels, and cadmium (Cd) was linked to increased TTE levels. No metal was significantly associated with E2 levels in trend analysis. In the analysis of effect modification, the associations of neighborhood walkability with TTE and E2 were significantly modified by Mn (P = 0.005) and Cu (P = 0.049) respectively.

CONCLUSION

Neighborhood walkability could be a favorable factor for E2 production during pregnancy, which may be inhibited by maternal exposure to heavy metals.

One in Four US Households Likely Exceed New Soil Lead Guidance Levels

Lead exposure has blighted communities across the United States (and the globe), with much of the burden resting on lower income communities, and communities of color. On 17 January 2024, the US Environmental Protection Agency (USEPA) lowered the recommended screening level of lead in residential soils from 400 to 200 parts per million. Our analysis of tens of thousands of citizen-science collected soil samples from cities and communities around the US indicates that nearly one quarter of households may contain soil lead that exceed the new screening level. Extrapolating across the nation, that equates to nearly 30 million households needing to mitigate potential soil lead hazards, at a potential total cost of 290 billion to $1.2 trillion. We do not think this type of mitigation is feasible at the massive scale required and we have instead focused on a more immediate, far cheaper strategy: capping current soils with clean soils and/or mulch. At a fraction of the cost and labor of disruptive conventional soil mitigation, it yields immediate and potentially life-changing benefits for those living in these environments.

Neighborhood-scale lead (Pb) speciation in Akron, Ohio (USA) soils: primary sources, post-deposition diagenesis, and high concentrations of labile Pb

Lead (Pb) poses a significant risk to infants and children through exposure to contaminated soil and dust. However, there is a lack of information on Pb speciation and distribution at the neighborhood-scale. This work aimed to determine: (1) the distribution of acid-extractable (labile) Pb and other metals ([M]AE) in two neighborhoods in Akron, Ohio (USA) (Summit Lake and West Akron; n = 82 samples); and (2) Pb speciation and potential sources. Total metal concentration ([M]T) and [M]AE was strongly correlated for Pb and Zn (R2 of 0.66 and 0.55, respectively), corresponding to 35% and 33% acid-extractability. Lead and Zn exhibited a strong positive correlation with each other (R2 = 0.56 for MT and 0.68 for MAE). Three types of Pb-bearing phases were observed by electron microscopy: (1) galena (PbS)-like (5-10 μm); (2) paint chip residuals (10-20 μm); and (3) Pb-bearing Fe-oxides (20 μm). Isotope ratio values for PbAE were 1.159 to 1.245 for 206Pb/207Pb, and 1.999 to 2.098 for 208Pb/206Pb, and there was a statistically significant difference between the two neighborhoods (p = 0.010 for 206Pb/207Pb and p = 0.009 for 208Pb/206Pb). Paint and petrol are the dominant sources of Pb, with some from coal and fly ash. Lead speciation and distribution is variable and reflects a complex relationship between the input of primary sources and post-deposition transformations. This work highlights the importance of community science collaborations to expand the reach of soil sampling and establish areas most at risk based on neighborhood-dependent Pb speciation and distribution for targeted remediation.

Widespread Pb contamination in urban backyard soils for >100 years identified in soil cores constrained by 210Pb and 137Cs

Contaminated soil in urban residential areas is often overlooked as a source of childhood exposure to toxic levels of lead (Pb). We document mean Pb concentrations of 1200 ± 1000 mg/kg, three times the now outdated EPA soil hazard standard of 400 mg/kg, for 370 surface soils collected from 76 homes in the boroughs of Brooklyn and Manhattan of New York City. The mean Pb content of 250 ± 290 mg/kg Pb for 571 surface soils collected from tree pits and public parks was much lower. A subset of 22 surface samples analyzed by EPA Method 1340 extracted 86 ± 21 % (±1SD) of total soil Pb, indicating that it the Pb was highly bioavailable. To investigate the origin of backyard contamination, 49 cores were collected to an average depth of 30 cm from a subset of 27 homes. Twelve soil cores were analyzed for 210Pb and 137Cs to constrain processes that impact contaminant distribution and inventories (particle focusing, soil accumulation, loss, and mixing). Concentrations of Pb declined with depth in 60 % of the cores but usually did not reach background. Mean uncorrected Pb inventories of 340 ± 210 g/m2 Pb (mean ± 1SD, n = 12) were more than five times higher than the radionuclide corrected inventory of 57 g/m2 from Central Park soil cores. Average inventories of 210Pbxs (3.5 ± 0.9 kBq/m2) and 137Cs (0.9 ± 0.6 kBq/m2) corresponded to 71 ± 19 % and 50 ± 30 % of the predicted atmospheric inventories. Elevated Pb concentrations were found both in the fine (<1 mm) and coarse (>1 mm) fractions, the latter suggesting a local non-atmospheric source. This was confirmed by individual grains containing up to 6 % Pb and visible pieces of coal, bricks, and ash. Regardless of the source of contamination in backyard soils, systematic testing is needed to identify contaminated areas and reduce child exposure.

Using blood lead concentrations of wildlife sentinels to identify environmental risk factors of lead exposure for public health and wildlife rehabilitation efforts

Lead poisoning remains a persistent health issue for both humans and wildlife, despite strides to reduce lead contamination in the environment. Using Geographic Information Systems (GIS), this study explores the associations between blood lead levels (BLLs) in wildlife sentinels and possible built environment lead exposure risk factors in the Minneapolis-Saint Paul, Minnesota urban area. Results show a high-level of heterogeneity in animal BLLs (n = 472) across our urban environment and suggest that each kilometer increase in road density is associated with a 17.07% (95% CI: 1.48%, 35.05%) increase in BLL in our study species of Virginia opossums and Eastern gray squirrels, and a 14.28% (95% CI: 1.16%, 29.09%) increase in BLL of rock pigeons. For squirrels and opossums, we see an additional 5.72% (95% CI: 0.59%, 10.85%) increased risk of BLL for every 1000 people per square-mile. The relationship between animal sentinels and environmental hazards can give us an insight into the potential lead exposure risks for humans. The use of wildlife sentinel data to explore environmental risk factors supports a One Health approach to better address public health questions and aid in wildlife rehabilitation related to residual lead poisoning from ambient environmental exposures.

Sentinel animals for monitoring the environmental lead exposure: combination of traditional review and visualization analysis

In nature, certain animals share a common living environment with humans, thus these animals have become biomonitors of health effects related to various environmental exposures. As one of the most toxic environmental chemicals, lead (Pb) can cause detriment health effects to animals, plants, and even humans through different exposure pathways such as atmosphere, soil, food, water, and dust, etc. Sentinel animals played an "indicative" role in the researches of environmental pollution monitoring and human health. In order to comprehend the usage of sentinel animals in the indication of environmental Pb pollution and human Pb exposure completely, a combination of traditional review and visualization analysis based on CiteSpace literature was used to review earlier researches in this study. In the first instance, present researches on exposure sources and exposure pathways of Pb were summarized briefly, and then the studies using sentinel animals to monitor environmental heavy metal pollution and human health were combed. Finally, visualization software CiteSpace 5.8.R3 was used to explore and analyze the hotspots and frontiers of lead exposure and sentinel animals researches at home and abroad. The results showed that certain mammals were good indicators for human lead exposure. Sentinel animals had been widely used to monitor the ecological environment and human lead exposure. Among them, the blood lead levels of small mammals, particularly for domestic dogs and cats, had a significant correlation with the blood lead levels of human living in the same environment. It indicated that certain biological indicators in animals can be used as surrogates to monitor human body exposure to heavy metals. This study also explored the challenges and perspectives that may be faced in sentinel animal research, in order to provide a certain theoretical basis and train of thought guidance for future research.

Incorporating field-based research into remote learning: An assessment of soil lead pollution in different land-use types in Los Angeles

A research-based course was developed to investigate the legacy of soil lead (Pb) pollution in Los Angeles, California. During the course, undergraduate and graduate students collected a total of 270 soil samples for analyses of metal (loid) concentrations in different land-use types (residential, park, and school). Residential soils had significantly higher Pb concentrations than other land uses (p < 0.01) exceeding the California recommended safety level for soil Pb (80 mg/kg) at the highest frequency (64% of samples), followed by schools (42%) and parks (6.0%). Soil Pb from all 87 census block groups was correlated with battery recycling plant and railroad proximity as geospatial indicators of childhood Pb exposure risk. Meanwhile, census block groups with higher Pb levels were correlated with higher percentages of the following population: those without health insurance, without college degrees, with a lower median household income and income below the poverty line, and ethnic and racial minorities (r = -0.46 to 0.59, p < 0.05). Principal component regression models significantly improved soil Pb estimation over correlation analysis by incorporating sociodemographic, economic, and geospatial risk factors for Pb exposure (R² = 0.58, p < 0.05). This work provides new insights into how topsoil Pb prevails in various land-use types and their co-occurring sociodemographic, economic, and geospatial risk factors, indicating the need for multi-scalar assessment across urban land uses.

Using community science for detailed pollution research: a case-study approach in Indianapolis, IN, USA

Heavy metal contamination in urban environments, particularly lead (Pb) pollution, is a health hazard both to humans and ecological systems. Despite wide recognition of urban metal pollution in many cities, there is still relatively limited research regarding heavy metal distribution and transport at the household-scale between soils and indoor dusts-the most important scale for actual human interaction and exposure. Thus, using community-scientist-generated samples in Indianapolis, IN (USA), we applied bulk chemistry, Pb isotopes, and scanning electron microscopy (SEM) to illustrate how detailed analytical techniques can aid in interpretation of Pb pollution distribution at the household-scale. Our techniques provide definitive evidence for Pb paint sourcing in some homes, while others may be polluted with Pb from past industrial/vehicular sources. SEM revealed anthropogenic particles suggestive of Pb paint and the widespread occurrence of Fe-rich metal anthropogenic spherules across all homes, indicative of pollutant transport processes. The variability of Pb pollution at the household scale evident in just four homes is a testament to the heterogeneity and complexity of urban pollution. Future urban pollution research efforts would do well to utilize these more detailed analytical methods on community-sourced samples to gain better insight into where the Pb came from and how it currently exists in the environment. However, these methods should be applied after large-scale pollution screening techniques such as portable X-ray fluorescence (XRF), with more detailed analytical techniques focused on areas where bulk chemistry alone cannot pinpoint dominant pollution mechanisms and where community scientists can also give important metadata to support geochemical interpretations.

Source apportionment based on lead isotope ratios: Could domestic dog's blood lead be used to identify the level and sources of lead pollution in children?

Domestic dogs have been proved to be used as "sentinel organisms" to monitor human lead exposure. However, whether dogs' blood can be used to identify the levels and pollution source of children's lead exposure still needs evidence. To evaluate the potential use of domestic dogs' blood lead as an indicator of lead exposure levels and pollution source of children, accompanying with potential environmental media samples, lead concentrations and isotope ratios (expressed as ²⁰⁷Pb/²⁰⁶Pb, ²⁰⁸Pb/²⁰⁶Pb) in blood were investigated and compared between children and dogs, who came from a Pb-Zn smelter area, a coal fired area and a control area without industrial activity. The results showed that there were significant correlations in blood lead levels (BLLs) between children and dogs in the study areas (p < 0.01). The lead isotope ratios (LIRs) in blood of children and dogs were disparate among the three areas, however, the LIRs of dogs were quite correlated with those of children in each area (p < 0.01). With the comparison of LIRs between potential pollution sources (slag, ore, coal, paint) and blood samples, the identified lead sources based on dogs' blood were found to be coincident with those based on children's blood. Ore smelting and coal combustion were the main sources of lead exposure for the dogs and children in the smelting area, and coal combustion was the predominant source for the children and dogs living in the coal burning area and control area. The results showed that dogs' BLLs might be used to estimate children's BLLs, and blood LIRs measurements of dogs' could be used as an alternative for identifying the sources of children's lead exposure. This study further provided relevant evidence for dogs to be sentinels exposed to human lead exposure and an alternative method for source apportionment of children's lead exposure.

Contamination Evaluation and Source Analysis of Heavy Metals in Karst Soil Using UNMIX Model and Pb-Cd Isotopes

Karst terrain is the typical area covered with a high background of heavy metals under geochemical anomaly. This research explored the accumulation of geochemical elements and soil sources in karst terrain from rock and soil exposed in carbonate areas. The comprehensive ecological risk and enrichment of heavy metals from parent rock weathered to soil was investigated in 11 formations in the carbonate and clastic areas of the Weining and Hezhang counties in northwest Guizhou. The single factor pollution index, geoaccumulation index, and the potential risk coefficient were used to assess the environmental risk. The results revealed that the heavy metals in an overall geologically high background level of soil in northwest Guizhou is at a slight risk level. However, except for Cd, the heavy metals did not exceed the standard pollution reference. Moreover, the UNMIX model and Cd and Pb isotopes were used to analyze the source of heavy metals, comprising of cadmium (Cd), arsenic (As), lead (Pb), chromium (Cr), copper (Cu), nickel (Ni), and zinc (Zn), and the geochemical elements of silicon (Si), aluminum (Al), iron (Fe), magnesium (Mg), and calcium (Ca). The study showed that most elements in the soil carbonate area exceed the national standard, and the heavy metals in the soil showed a strong enrichment, while the major elements Si and Mg display strong loss. Heavy metal concentrations in soil in the carbonate area were higher than in the clastic area. Geological sources and atmospheric deposition were the main contributors to heavy metal concentrations in both carbonate and clastic areas, and their concentrations differ according to soils developing in different formations.

Lead in Air, Soil, and Blood: Pb Poisoning in a Changing World

(1) Background: Leaded petrol became a worldwide vehicle fuel during the 20th century. While leaded petrol was totally banned on 30 August 2021, its lead (Pb) dust legacy remains in the environment as soil Pb. The health impacts of Pb are well known and risks occur when exposures are above zero. The inextricable links between air Pb, soil Pb, and blood Pb are not widely A. Exposure risks continue even after banning leaded petrol and must be explored. (2) Methods: This article evaluates selected examples of temporal measurements of atmospheric Pb and human Pb exposure and the effect of soil Pb on blood Pb. Several search engines were used to find articles on temporal changes in air Pb and human Pb exposures. New Orleans studies provided empirical data on the association between soil Pb and blood Pb. (3) Results: Vehicle Pb emission trends are closely associated with air Pb and blood Pb. Air Pb deposited in soil becomes a reservoir of Pb dust that is known to be remobilized into the atmosphere. (4) Conclusions: The dust from leaded petrol continues to pose major exposure risks to humans. Exogenous sources of Pb in soil and its remobilization into air along with endogenous bone Pb establish the baseline exposure of children and adults. Reducing human exposure to Pb requires novel policies to decrease exogenous contact from the reservoir of Pb in soil and curtailing remobilization of soil Pb into the atmosphere. Mitigating exposure to soil Pb must therefore play a central role in advancing primary prevention.

The Current State of Community Engagement in Urban Soil Pollution Science

Environmental burdens disproportionately impact the health of communities of color and low-income communities. Contemporary and legacy industry and land development may pollute soils with pesticides, petroleum products, and trace metals that can directly and indirectly impact the health of frontline communities. Past efforts to study environmental injustice have often excluded those most impacted, created distrust of researchers and other experts among frontline communities, and resulted in little to no structural change. Prevailing research methods value formal knowledge systems, while often dismissing the knowledge of those most harmed by environmental hazards. Community science has emerged as a process of doing science that centers the participation of community members, who may co-develop research questions, inform study methods, collect data, interpret findings, or implement projects. While community science is one of several research methods that can advance community goals, it can also be implemented in ways that are extractive or harm communities. Research on best practices for community science is robust; however, how community science has been used in urban soil research is not well understood. We identified sixteen relevant urban soil studies published between 2008 and 2021 that used community science methods or engaged with community members around soil pollution. We then assessed the selected studies using two community engagement models to better understand community engagement practices in urban soil pollution science. The Spectrum of Community Engagement to Ownership (SCEO) model, which organizes engagement from level 0 (ignore) to 5 (defer to) was used to assess all studies. Studies that explicitly aimed to co-develop research with the community were additionally assessed using the Urban Sustainability Directors Network High Impact Practices (USDN HIPs). The majority of the studies assessed were aligned with levels 1–3 of the SCEO. Studies assessed as levels 4–5 of the SCEO were associated with delegating power to communities, community engages decision-making, creating space for community voices, and remediation efforts. We propose that future urban remediation soil pollution work that engages at higher levels of the SCEO and employs USDN HIPs, will be more effective at addressing crucial environmental health challenges by supporting, equitable, inclusive, and sustainable solutions.

Defining the Exposome Using Popular Education and Concept Mapping With Communities in Atlanta, Georgia

Introduction

The exposome concept provides a framework to better incorporate the environment into the study of health and disease and has been defined by academics to encompass all lifetime exposures including toxicants, diet, and lifestyle choices. However, initial applications of the exposome concept have been less apt at measuring social determinants of health, focusing primarily on conventional environmental exposures and lifestyle choices that do not reflect the complex lived experience of many communities. To bring community voice into the exposome concept, the HERCULES Exposome Research Center and its Stakeholder Advisory Board co-developed the Exposome Roadshow. We present and discuss the resulting community-exposome definition to inform and improve exposome research.

Materials and Methods

Four communities from distinct areas across metro-Atlanta participated in separate 2-day Exposome Roadshow workshops with concept mapping. Aligned with a popular education approach in which community knowledge is used to work collectively for change, concept mapping provided a systematic method to collect and visualize community members' knowledge and create a shared understanding to take action. Community members brainstormed, sorted, and rated their responses to the prompt: "What in your environment is affecting your and your community's health?" Responses were analyzed and visually depicted by concept maps consisting of separate but interrelated clusters of ideas. Community members discussed and validated the maps, selecting a final map illustrating their community's exposome.

Results

A total of 118 community members completed concept mapping. On average communities identified 7 clusters to define their exposome. The resulting concept maps offer a community definition of the exposome. Five major themes arose across all four communities: conventional environmental concerns, built environment, social relationships, crime and safety, and individual health and behaviors.

Discussion

The resulting community-exposome definition demonstrates the importance of expanding the scope of exposures beyond traditional environmental influences to include the lived experience of individuals and communities. While newer exposome definitions align more closely with this community definition, traditional exposome methods do not routinely include these factors. To truly capture the totality of lifetime exposures and improve human health, researchers should incorporate community perspectives into exposome research.

Potentially Toxic Elements in Urban Soils from Public-Access Areas in the Rapidly Growing Megacity of Lagos, Nigeria

Rapid urbanization can lead to significant environmental contamination with potentially toxic elements (PTEs). This is of concern because PTEs are accumulative, persistent, and can have detrimental effects on human health. Urban soil samples were obtained from parks, ornamental gardens, roadsides, railway terminals and locations close to industrial estates and dumpsites within the Lagos metropolis. Chromium, Cu, Fe, Mn, Ni, Pb and Zn concentrations were determined using inductively coupled plasma mass spectrometry following sample digestion with aqua regia and application of the BCR sequential extraction procedure. A wide range of analyte concentrations was found—Cr, 19−1830 mg/kg; Cu, 8−11,700 mg/kg; Fe, 7460−166,000 mg/kg; Mn, 135−6100 mg/kg; Ni, 4−1050 mg/kg; Pb, 10−4340 mg/kg; and Zn, 61−5620 mg/kg—with high levels in areas close to industrial plants and dumpsites. The proportions of analytes released in the first three steps of the sequential extraction were Fe (16%) < Cr (30%) < Ni (46%) < Mn (63%) < Cu (78%) < Zn (80%) < Pb (84%), indicating that there is considerable scope for PTE (re)mobilization. Human health risk assessment indicated non-carcinogenic risk for children and carcinogenic risk for both children and adults. Further monitoring of PTE in the Lagos urban environment is therefore recommended.

Legacy of anthropogenic lead in urban soils: Co-occurrence with metal(loids) and fallout radionuclides, isotopic fingerprinting, and in vitro bioaccessibility

Anthropogenic lead (Pb) in soils poses risks to human health, particularly to the neuropsychological development of exposed children. Delineating the sources and potential bioavailability of soil Pb, as well as its relationship with other contaminants is critical in mitigating potential human exposure. Here, we present an integrative geochemical analysis of total elemental concentrations, radionuclides of ¹³⁷Cs and ²¹⁰Pb, Pb isotopic compositions, and in vitro bioaccessibility of Pb in surface soils sampled from different locations near Durham, North Carolina. Elevated Pb (>400 mg/kg) was commonly observed in soils from urban areas (i.e., near residential house foundation and along urban streets), which co-occurred with other potentially toxic metal(loids) such as Zn, Cd, and Sb. In contrast, soils from city parks and suburban areas had systematically lower concentrations of metal(loids) that were comparable to geological background. The activities of ¹³⁷Cs and excess ²¹⁰Pb, coupled with their correlations with Pb and co-occurring metal(loids) were used to indicate the persistence and remobilization of historical atmospherically deposited contaminants. Coupled with total Pb concentrations, the soil Pb isotopic compositions further indicated that house foundation soils had significant input of legacy lead-based paint (mean = 1.1895 and 2.0618 for ²⁰⁶Pb/²⁰⁷Pb and ²⁰⁸Pb/²⁰⁶Pb, respectively), whereas urban streetside soils exhibited a clear mixed origin, dominantly of legacy leaded gasoline (1.2034 and 2.0416) and atmospheric deposition (1.2004-1.2055 and 2.0484-2.0525). The in vitro bioaccessibility of Pb in contaminated urban soils furthermore revealed that more than half of Pb in the contaminated soils was potentially bioavailable, whose Pb isotope ratios were identical to that of bulk soils, demonstrating the utility of using Pb isotopes for tracking human exposure to anthropogenic Pb in soils and house dust. Overall, this study demonstrated a holistic assessment for comprehensively understanding anthropogenic Pb in urban soils, including its co-occurrence with other toxic contaminants, dominant sources, and potential bioavailability upon human exposure.

Using Community Science to Better Understand Lead Exposure Risks

Lead (Pb) is a neurotoxicant that particularly harms young children. Urban environments are often plagued with elevated Pb in soils and dusts, posing a health exposure risk from inhalation and ingestion of these contaminated media. Thus, a better understanding of where to prioritize risk screening and intervention is paramount from a public health perspective. We have synthesized a large national data set of Pb concentrations in household dusts from across the United States (U.S.), part of a community science initiative called "DustSafe." Using these results, we have developed a straightforward logistic regression model that correctly predicts whether Pb is elevated (>80 ppm) or low (<80 ppm) in household dusts 75% of the time. Additionally, our model estimated 18% false negatives for elevated Pb, displaying that there was a low probability of elevated Pb in homes being misclassified. Our model uses only variables of approximate housing age and whether there is peeling paint in the interior of the home, illustrating how a simple and successful Pb predictive model can be generated if researchers ask the right screening questions. Scanning electron microscopy supports a common presence of Pb paint in several dust samples with elevated bulk Pb concentrations, which explains the predictive power of housing age and peeling paint in the model. This model was also implemented into an interactive mobile app that aims to increase community-wide participation with Pb household screening. The app will hopefully provide greater awareness of Pb risks and a highly efficient way to begin mitigation.

International Analysis of Sources and Human Health Risk Associated with Trace Metal Contaminants in Residential Indoor Dust

People spend increasing amounts of time at home, yet the indoor home environment remains understudied in terms of potential exposure to toxic trace metals. We evaluated trace metal (and metalloid) concentrations (As, Cu, Cr, Mn, Ni, Pb, and Zn) and health risks in indoor dust from homes from 35 countries, along with a suite of potentially contributory residential characteristics. The objective was to determine trace metal source inputs and home environment conditions associated with increasing exposure risk across a range of international communities. For all countries, enrichments compared to global crustal values were Zn > Pb > Cu > As > Cr > Ni; with the greatest health risk from Cr, followed by As > Pb > Mn > Cu > Ni > Zn. Three main indoor dust sources were identified, with a Pb-Zn-As factor related to legacy Pb sources, a Zn-Cu factor reflecting building materials, and a Mn factor indicative of natural soil sources. Increasing home age was associated with greater Pb and As concentrations (5.0 and 0.48 mg/kg per year of home age, respectively), as were peeling paint and garden access. Therefore, these factors form important considerations for the development of evidence-based management strategies to reduce potential risks posed by indoor house dust. Recent findings indicate neurocognitive effects from low concentrations of metal exposures; hence, an understanding of the home exposome is vital.

Functional consequences of lead and mercury exposomes in the heart

Lead and mercury are heavy metals that are highly toxic to life forms. There are no known physiological processes that require them, and they do not have a particular threshold concentration to produce biologic damage. They are non-biodegradable, and they slowly accumulate in the environment in a dynamic equilibrium between air, water, soil, food, and living organisms. Their accumulation in the environment has been increasing over time, because they were not banned from use in anthropogenic industrial production. In their +2 cationic state they are powerful oxidizing agents with the ability to interfere significantly with processes that require specific divalent cations. Acute or chronic exposure to lead and mercury can produce multisystemic damage, especially in the developing nervous systems of children and fetuses, resulting in variety of neurological consequences. They can also affect the cardiovascular system and especially the heart, either directly through their action on cardiomyocytes or indirectly through their effects on innervation, humoral responses or blood vessel alterations. For example, heart function modified by these heavy metals are heart rate, contraction, excitability, and rhythm. Some cardiac molecular targets have been identified and characterized. The direct mechanisms of damage of these heavy metals on heart function are discussed. We conclude that exposome to these heavy metals, should be considered as a major relevant risk factor for cardiac diseases.

Testing Homes for Potential Sources of Lead Exposure as a High-School Science Project

High-school students tested soil, paint, and water for lead (Pb) in a total of 80 houses in their town of Pelham, New York, where blood-Pb data indicate relatively high levels of child exposure. All the samples were tested in the laboratory using established procedures but this was preceded by testing of soil and paint in the field with a kit by the students. The total Pb concentration in 32 of the 159 soil samples that were collected exceeded 400 ppm, the EPA standard for bare soil in residential areas where children play. Only 4 of the 118 tap water samples that were collected contained over 15 ppb Pb, with the data showing that flushing for 2 min clearly lowered Pb concentration further across the board. The highest risk of child exposure may be posed by old Pb-based paint, however, which was detected in 9 of the 48 samples that were tested. Residents were also the least willing to let the students test or sample their paint. High-school students could help reduce exposure in the many towns where child blood-Pb levels remain high today by identifying sources and, while doing so, learn about environmental science and measurement from this hands-on experience.

Quantification of Pb pollution sources in complex urban environments through a multi-source isotope mixing model based on Pb isotopes in lichens and road sediment

Despite a growing focus on anthropogenic toxic metal pollution in urban environments, few studies have addressed the problem of quantification when more than two pollution sources are likely present, particularly within complex urban settings in the United States (U.S.). In this study, we utilize the MixSIAR package in R for source apportionment based on Pb isotopic signatures in lichen and road sediment in two urban-industrial centers in SW Ohio (OH). We show that ranges of pollutant contributions are more useful than only visualizing mean or raw values of source apportionment, because this avoids overinterpretation of data when certain sources have a large range of uncertainty. We point out both the dominance of industrial pollution as well as the legacy of leaded gasoline pollution in typical mid-sized U.S. cities, which is evident in both road sediment and lichens. Leaded gasoline contribution to Pb in Middletown, OH lichens mostly vary between ~10 and 25%, while in Hamilton, OH the contribution to lichens and road sediment tends to be relatively negligible except for two road sediment samples and one lichen sample, where median contributions are ~20-30%. Industrial combustion pollution source contributions vary between ~25 and 75% in Hamilton, and ~50-100% in Middletown, OH. Furthermore, comparing pollution sources in lichens to modern particulate matter can provide a record of how pollutant sources change over time, such as our traffic lichen (Sample Li-9) plotting closer to leaded gasoline on a bivariate mixing diagram than modern traffic particulate matter, or our coke plant lichen containing slightly less Pb contribution from industrial combustion sources relative to modern coke plant particulate matter. Lastly, when applicable, multi-source mixing models should be complimented in future studies with additional isotopic source tracers such as Cu, Zn, Nd, and Os to further elucidate unique sources of metal pollutants in addition to Pb.

A citizen science approach to identifying trace metal contamination risks in urban gardens

We launched the VegeSafe program in 2013 to assist Australians concerned about exposure to contaminants in their soils and gardens. VegeSafe analyses garden soils provided by citizens for trace metals at our laboratory at little to no cost, with easy-to-follow guidance on any intervention required. The response was overwhelming-Australians submitted 17,256 soils from 3,609 homes, and in turn VegeSafe researchers now have unparalleled household-scale data, providing new insights into urban trace metal contamination. The results are sobering, with 35% of homes, particularly those that are older, painted and located in inner cities having soils above the Australian residential guideline (300 mg/kg) for the neurotoxic trace metal lead (Pb). Exposure pathway, blood Pb concentration and vegetable uptake modelling showed the communities in these locations were most at risk. VegeSafe is transformative: 94% of participants better understood contaminants, 83% felt safer in their home environment and 40% undertook remedial action based on their results. The two-way nature of this program enables education of citizens about environmental contaminants, advances public health, and delivers impactful science.

Exploring the Potential Risk of Heavy Metal Pollution of Edible Cultivated Plants in Urban Gardening Contexts Using a Citizen Science Approach in the Project “Heavy Metal City-Zen”

Urban gardening has become increasingly popular, creating green oases in cities; however, many of these activities are undertaken in areas of high traffic density or on ex-brown field sites. As a consequence, there are still some barriers to the adoption of these urban gardening practices for food production. One of the public concerns is the transfer of urban pollutants such as heavy metals into the consumer’s food chain, however, city-wide data is often difficult and expensive to collect. In the citizen science project described herein, we conducted simple citizen-led common collaborative experiments in urban community gardens. These data provided information on the potential risk of heavy metal contaminants and ways in which to mitigate those risks in an urban gardening context. Generally, values were below guideline thresholds, however, at a few garden sites, soil trace metal concentrations (Pb, Cd, Zn) exceeded Austrian recommended limits. Moreover, only at two sites were plant trace metal concentrations shown to be above European food standards limits. Given the citizen’s positive response to the project, we suggest expanding this study to the whole of Vienna, giving newly established gardens a chance to predetermine the risks posed by their local soils.

Environmental assessment of pediatric Lead exposure in Tehran; a prospective cross-sectional study

Background

Ingestion and inhalation are common routes of exposure for lead in humans. Developing countries still have unacceptably high rates of lead toxicity, especially in children. Studies on probable risk factors of lead poisoning in Iranian children are insufficient. In this study, we aimed to evaluate possible environmental factors in children with high blood lead concentrations living in Tehran and neighboring cities.

Methods

In a prospective cross-sectional study between March 2018 and March 2019 we followed all children referred from two pediatric gastrointestinal clinics with blood lead level (BLL) > 5 μg/dL in metropolitan Tehran to investigate possible environmental risk factors in their home. Household specimens including scratched wall paint, house floor dust, windowsill dust, tap water, and consumed spice were evaluated using atomic absorption method to detect lead concentrations. Epidemiological and environmental data collected through in-depth interviews with parents/guardians. Industrial areas were defined based on municipality maps on industrial places.

Results

Thirty of 56 parents/guardians with BLL > 5 μg/dL agreed to be followed through environmental investigation. The only categorical statistically significant risk factor was a history of lead poisoning in the family and living in an industrial zone. There was a positive correlation between BLL and interior windowsills dust lead level, r = 0.46, p = 0.01. Scratched paint lead level and BLL showed a significant positive correlation, r = 0.50, p = 0.005. House floor dust lead level (median = 77.4, p < 0.001) and interior windowsill dust lead level (median = 291, p = 0.011) were both significantly higher than the environmental protection agency (EPA) standards of 40 μg/ft2, 250 μg/ft2. Interior windowsill dust lead concentrations were significantly higher in industrial areas (p = 0.026).

Conclusion

Children’s playing environment should be cleaned more often to reduce dust. Moreover, specific rules may need to be implemented for paint lead concentrations and air pollution, especially in industrial areas.

Environmental assessment of pediatric Lead exposure in Tehran; a prospective cross-sectional study

BACKGROUND

Ingestion and inhalation are common routes of exposure for lead in humans. Developing countries still have unacceptably high rates of lead toxicity, especially in children. Studies on probable risk factors of lead poisoning in Iranian children are insufficient. In this study, we aimed to evaluate possible environmental factors in children with high blood lead concentrations living in Tehran and neighboring cities.

METHODS

In a prospective cross-sectional study between March 2018 and March 2019 we followed all children referred from two pediatric gastrointestinal clinics with blood lead level (BLL) > 5 μg/dL in metropolitan Tehran to investigate possible environmental risk factors in their home. Household specimens including scratched wall paint, house floor dust, windowsill dust, tap water, and consumed spice were evaluated using atomic absorption method to detect lead concentrations. Epidemiological and environmental data collected through in-depth interviews with parents/guardians. Industrial areas were defined based on municipality maps on industrial places.

RESULTS

Thirty of 56 parents/guardians with BLL > 5 μg/dL agreed to be followed through environmental investigation. The only categorical statistically significant risk factor was a history of lead poisoning in the family and living in an industrial zone. There was a positive correlation between BLL and interior windowsills dust lead level, r = 0.46, p = 0.01. Scratched paint lead level and BLL showed a significant positive correlation, r = 0.50, p = 0.005. House floor dust lead level (median = 77.4, p < 0.001) and interior windowsill dust lead level (median = 291, p = 0.011) were both significantly higher than the environmental protection agency (EPA) standards of 40 μg/ft², 250 μg/ft². Interior windowsill dust lead concentrations were significantly higher in industrial areas (p = 0.026).

CONCLUSION

Children's playing environment should be cleaned more often to reduce dust. Moreover, specific rules may need to be implemented for paint lead concentrations and air pollution, especially in industrial areas.

Delineation of the Urban-Rural Boundary through Data Fusion: Applications to Improve Urban and Rural Environments and Promote Intensive and Healthy Urban Development

As one of the most important methods for limiting urban sprawl, the accurate delineation of the urban-rural boundary not only promotes the intensive use of urban resources, but also helps to alleviate the urban issues caused by urban sprawl, realizing the intensive and healthy development of urban cities. Previous studies on delineating urban-rural boundaries were only based on the level of urban and rural development reflected by night-time light (NTL) data, ignoring the differences in the spatial development between urban and rural areas; so, the comprehensive consideration of NTL and point of interest (POI) data can help improve the accuracy of urban-rural boundary delineation. In this study, the NTL and POI data were fused using wavelet transform, and then the urban-rural boundary before and after data fusion was delineated by multiresolution segmentation. Finally, the delineation results were verified. The verification result shows that the accuracy of delineating the urban-rural boundary using only NTL data is 84.20%, and the Kappa value is 0.6549; the accuracy using the fusion of NTL and POI data on the basis of wavelet transform is 93.2%, and the Kappa value is 0.8132. Therefore, we concluded that the proposed method of using wavelet transform to fuse NTL and POI data considers the differences between urban and rural development, which significantly improves the accuracy of the delineation of urban-rural boundaries. Accurate delineation of urban-rural boundaries is helpful for optimizing internal spatial structure in both urban and rural areas, alleviating environmental problems resulting from urban development, assisting the formulation of development policies for urban and rural fringes, and promoting the intensive and healthy development of urban areas.

Characterising and communicating the potential hazard posed by potentially toxic elements in indoor dusts from schools across Lagos, Nigeria

Ambient and indoor air pollution results in an estimated 7 million premature deaths globally each year, representing a major contemporary public health challenge, but one poorly quantified from a toxicological and source perspective. Indoor exposure represents possibly the greatest potential overall exposure, yet our indoor environments are still poorly understood, modelled and characterized. In rapidly growing cities, such as Lagos, Nigeria, environmental monitoring can play an important role in establishing baseline data, monitoring urban pollution trends and in environmental education. Classroom dust samples were collected from 40 locations from across the twenty local government areas (LGAs) of Lagos, in June 2019. The aim of the study was to assess the potential hazard posed by PTE in indoor dusts and to develop a suitable risk communication strategy to inform and educate the public, promoting environmental health literacy. Concentrations of total PTE in indoor dusts were assessed using Energy Dispersive X-Ray Fluorescence (ED-XRF) spectrometry. Oral bioaccessibility determinations using the unified BARGE method, and analysis by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) were also performed on the dust samples to determine the fraction available for absorption in the gastrointestinal tract. Results showed that the indoor dust samples were largely uncontaminated, with only few exceptions (2 samples). Enrichment factor pollution trend for the total PTE concentrations was in the order of Pb > Zn > U > Cr > Cu > Ba > Mn > V > As > Cd > Ni > Al. Source apportionment studies using factor analysis suggests concentrations of Al, As, Fe, Mn, Ni, and U may be influenced largely by lithogenic factors, while Cd, Cu and Pb originated principally from anthropogenic sources. Chromium, V and Zn appear to originate from mixed sources of both lithogenic and anthropogenic origin. Our oral bioaccessibility determinations indicate that the assumption of 100% bioavailability based on pseudototal or total concentrations would overestimate the hazard potential of PTE in these indoor dusts. Zinc was the most bioaccessible PTE (mean of 88%), with Mn (57%), Pb (48%), Ba (48%), Al (41%), As (37%), Cu (36%), Ni (28%), Cr (10%) and Fe (7%) the least bioaccessible. Human health risk assessment, for both children and adults using the bioaccessible fraction, showed values to be within acceptable risk levels.

Characterization and within-site variation of environmental metal concentrations around a contaminated site using a community-engaged approach

Historic industrial activity led to extensive lead and arsenic contamination within residential areas of East Chicago, Indiana, United States. Although remediation is underway, community concerns about this contamination remain. Therefore, the goal for this analysis was to characterize environmental contamination in soil within and around these areas. A total of 228 samples from 32 different sites (addresses) were collected by community members or study staff. These were analyzed for metals using portable x-ray fluorescence or inductively coupled plasma ̶ optical emission spectroscopy. Concentrations exceeding EPA screening levels were found for 42% of the soil arsenic samples, 35% of the soil lead samples, and 79% of the soil manganese samples; a few samples also contained elevated copper or zinc. Concentrations above EPA screening levels were identified both within and outside of the formally designated contaminated area. Roughly 30% of all sites had at least one sample above and one sample below the screening level for arsenic, lead, and manganese. For sites within the contaminated area, more than 90% (arsenic), 60% (lead) and 60% (manganese) of the samples exceeded EPA screening levels. There was a significant association of proximity to the historic industrial site with elevated soil concentrations of arsenic and lead; a similar association was present for manganese. These results are consistent with existing data for lead and arsenic and we additionally report elevated concentrations of manganese and a high within-site variability of all metal concentrations. These findings should be considered in future remediation efforts.

Soil lead (Pb) and urban grown lettuce: Sources, processes, and implications for gardener best management practices

Urban community gardeners employ a range of best practices that limit crop contamination by toxicants like lead (Pb). While Pb root uptake is generally low, the relative significance of various Pb deposition processes and the effectiveness of best practices in reducing these processes have not been sufficiently characterized. This study compared leafy lettuce (Lactuca sativa) grown in high Pb (1150 mg/kg) and low Pb (90 mg/kg) soils, under three different soil cover conditions: 1) bare soil, 2) mulch cover to limit splash, and 3) mulch cover under hoophouses to limit splash and air deposition, in a New York City (NYC) community garden and a rural site in Ithaca, New York (NY). The lettuces were further compared to greenhouse (Ithaca) and supermarket (NYC) samples. Atmospheric deposition was monitored by passive trap collection through funnel samplers. Results show that in low Pb soils, splash and atmospheric deposition accounted for 84 and 78% of lettuce Pb in NYC and Ithaca, respectively. In high Pb soils, splash and atmospheric deposition accounted for 88 and 93% of Pb on lettuces, with splash being the dominant mechanism. Soil covers were shown to be effective at significantly (p < 0.05) reducing lettuce Pb contamination, and mulching is strongly recommended as a best practice.

Lead Distribution in Urban Soil in a Medium-Sized City: Household-Scale Analysis

This study characterizes potential soil lead (Pb) exposure risk at the household scale in Greensboro, North Carolina, using an innovative combination of field sampling, statistical analysis, and machine-learning techniques. Soil samples were collected at the dripline, yard, and street side at 462 households (total sample size = 2310). Samples were analyzed for Pb and then combined with publicly available data on potential historic Pb sources, soil properties, and household and neighborhood demographic characteristics. This curated data set was then analyzed with statistical and machine-learning techniques to identify the drivers of potential soil Pb exposure risks and to build predictive models. Among all samples, 43% exceeded current guidelines for Pb in residential gardens. There were significant racial disparities in potential soil Pb exposure risk; soil Pb at the dripline increased by 19% for every 25% increase in the neighborhood population identifying as Black. A machine-learned Bayesian network model was able to classify residential parcels by risk of exceeding residential gardening standards with excellent reproducibility in cross validation. These findings underscore the need for targeted outreach programs to prevent Pb exposure in residential areas and demonstrate an approach for prioritizing outreach locations.

The urban lead (Pb) burden in humans, animals and the natural environment

Centuries of human activities, particularly housing and transportation practices from the late 19th century through the 1980's, dispersed hundreds of millions of tons of lead into our urban areas. The urban lead burden is evident among humans, wild and domesticated animals, and plants. Animal lead exposures closely mirror and often exceed the lead exposure patterns of their human partners. Some examples: Pigeons in New York City neighborhoods mimicked the lead exposures of neighborhood children, with more contaminated areas associated with higher exposures in both species. Also, immediately following the lead in drinking water crisis in Flint MI in 2015, blood lead levels in pet dogs in Flint were 4 times higher than in surrounding towns. And combining lead's neurotoxicity with urban stress results in well-characterized aggressive behaviors across multiple species. Lead pollution is not distributed evenly across urban areas. Although average US pediatric lead exposures have declined by 90% since the 1970s, there remain well defined neighborhoods where children continue to have toxic lead exposures; animals are poisoned there, too. Those neighborhoods tend to have disproportionate commercial and industrial lead activity; a history of dense traffic; older and deteriorating housing; past and operating landfills, dumps and hazardous waste sites; and often lead contaminated drinking water. The population there tends to be low income and minority. Urban wild and domesticated animals bear that same lead burden. Soil, buildings, dust and even trees constitute huge lead repositories throughout urban areas. Until and unless we begin to address the lead repositories in our cities, the urban lead burden will continue to impose enormous costs distributed disproportionately across the domains of the natural environment. Evidence-based research has shown the efficacy and cost-effectiveness of some US public policies to prevent or reduce these exposures. We end with a series of recommendations to manage lead-safe urban environments.

Soil Lead Concentration and Speciation in Community Farms of Newark, New Jersey, USA

Farmed urban soils often bear legacies of historic contamination from anthropogenic and industrial sources. Soils from seven community farms in Newark, New Jersey (NJ), USA, were analyzed to determine the concentration and speciation of lead (Pb) depending on garden location and cultivation status. Samples were evaluated using single-step 1 M nitric acid (HNO3) and Tessier sequential extractions in combination with X-ray absorption fine structure spectroscopy (XAFS) analysis. Single-step extractable Pb concentration ranged from 22 to 830 mg kg−1, with 21% of samples reporting concentrations of Pb > 400 mg kg−1, which is the NJ Department of Environmental Protection (NJDEP) limit for residential soils. Sequential extractions indicated lowest Pb concentrations in the exchangeable fraction (0–211 mg kg−1), with highest concentrations (0–3002 mg kg−1) in the oxidizable and reducible fractions. For samples with Pb > 400 mg kg−1, Pb distribution was mostly uniform in particle size fractions of <0.125–1 mm, with slightly higher Pb concentrations in the <0.125 mm fraction. XAFS analysis confirmed that Pb was predominantly associated with pyromorphite, iron–manganese oxides and organic matter. Overall results showed that lowest concentrations of Pb are detected in raised beds, whereas uncultivated native soil and parking lot samples had highest values of Pb. As most of the Pb is associated with reducible and oxidizable soil fractions, there is a lower risk of mobility and bioavailability. However, Pb exposure through ingestion and inhalation pathways is still of concern when directly handling the soil. With increasing interest in urban farming in cities across the USA, this study highlights the need for awareness of soil contaminants and the utility of coupled macroscopic and molecular-scale geochemical techniques to understand the distribution and speciation of soil Pb.

Investigating the Potential Impact of Louisiana Coastal Restoration on the Trace Metal Geochemistry of Constructed Marshlands

Coastal restoration through diversion of suspended sediments from the Lower Mississippi River (LMR) into hydrologically isolated marshlands of Mid-Barataria Bay and Mid-Breton Sounds in southern Louisiana has the potential to mobilize lead (Pb), and other trace elements. We investigate the potential impact(s) of the diversion on marsh porewater through analysis of modern riverbank and suspended sediments, compared to sediments from pre-industrial deltaic deposits of LMR. Sequential extraction methods were used to evaluate Pb, cobalt (Co), copper (Cu), nickel (Ni), and zinc (Zn) in the sediments. Our results show that metal contents are higher (e.g., 8- to 10-fold for Pb) in the modern sediments relative to pre-industrial deposits. Also, the reducible fraction, presumably iron/manganese (Fe/Mn) oxides/oxyhydroxides, is the chief reservoir of environmentally available metals. The substantially higher trace metal contents of the modern relative to pre-industrial sediments suggest that the modern sediments contain a sizeable amount of anthropogenic contributions. Furthermore, the concentration of the trace metals in the reducible fraction suggests bioavailability to marsh organisms upon reductive dissolution within the planned, constructed coastal marshes. Still, additional sediment samples from the marshlands during the diversion implementation phase will be necessary to support the preliminary findings in this contribution as it affects coastal marshes and vital local fisheries.

Research data management in health and biomedical citizen science: practices and prospects

Background

Public engagement in health and biomedical research is being influenced by the paradigm of citizen science. However, conventional health and biomedical research relies on sophisticated research data management tools and methods. Considering these, what contribution can citizen science make in this field of research? How can it follow research protocols and produce reliable results?

Objective

The aim of this article is to analyze research data management practices in existing biomedical citizen science studies, so as to provide insights for members of the public and of the research community considering this approach to research.

Methods

A scoping review was conducted on this topic to determine data management characteristics of health and bio medical citizen science research. From this review and related web searching, we chose five online platforms and a specific research project associated with each, to understand their research data management approaches and enablers.

Results

Health and biomedical citizen science platforms and projects are diverse in terms of types of work with data and data management activities that in themselves may have scientific merit. However, consistent approaches in the use of research data management models or practices seem lacking, or at least are not prevalent in the review.

Conclusions

There is potential for important data collection and analysis activities to be opaque or irreproducible in health and biomedical citizen science initiatives without the implementation of a research data management model that is transparent and accessible to team members and to external audiences. This situation might be improved with participatory development of standards that can be applied to diverse projects and platforms, across the research data life cycle.

Validation of a screening kit to identify environmental lead hazards

In many states, environmental lead hazards are evaluated only after a lead-poisoned child has been identified. This passive approach is problematic because only a small fraction of children are tested for lead and those with elevated blood lead levels may have irreversible developmental damage. In order to reverse this paradigm, a new lead screening kit was developed. In this study, we validated the accuracy of the kit compared to the conventional methods. Forty-five participants used the kit to collect 3 dust, 3 soil and 2 paint samples in their homes. A researcher performed an in-situ analysis of the lead content in the paint and soil using a portable X-ray fluorescence (XRF) spectrometer. The soil, paint, and dust samples collected by the participants were then analyzed by XRF ex-situ. A strong linear correlation was found between the in-situ and ex-situ measurements for soil and dust samples, and a reasonable correlation was obtained for lead content of paint samples. The kit had very high degrees of specificity (true negative rate) and sensitivity (true positive rate) for detecting hazardous levels of lead in soil and dust samples. The agreement was more moderate for paint samples because some of the paint chips provided gave different readings from the front or back surface, but in-situ XRF only reads from the front surface. Overall, the kit gave a sensitivity of 87%, a specificity of 98% and an accuracy of 96% for detection of environmental lead hazards in samples collected from the home by untrained citizens. This suggests that widespread and inexpensive lead screening could be used to successfully identify hazards and ultimately decrease environmental lead exposure in children.

Lead Exposure and Cardiovascular Disease among Young and Middle-Aged Adults

Lead and its effects on cardiovascular-related markers were explored in this cross-sectional study of young adults (18–44 years) and middle-aged adults (45–65 years) from the United States using the National Health and Nutrition Examination Survey (NHANES), 2009–2016. Degrees of exposure were created using blood lead level (BLL) as the biomarker of exposure based on the epidemiologically relevant threshold of BLL > 5 μg/dL. The mean values, in addition to the percentages of people represented for the markers of interest (systolic blood pressure [SBP], diastolic blood pressure [DBP], gamma-glutamyl transferase [GGT], non-high-density lipoprotein cholesterol [non-HDL-C]) were explored. Among those exposed to lead, the likelihood of elevated clinical markers (as defined by clinically relevant thresholds of above normal) were examined using binary logistic regression. In exploring exposure at the 5 μg/dL levels, there were significant differences in all the mean variables of interest between young and middle-aged adults. The binary logistic regression showed young and middle-aged adults exposed to lead were significantly more likely to have elevated markers (apart from DBP). In all, lead affects cardiovascular-related markers in young and middle-aged U.S. adults and thus we must continue to monitor lead exposure to promote health.

Measuring Copper, Lead and Zinc Concentrations and Oral Bioaccessibility as Part of the Soils in Scottish Schools Project

Determination of potentially toxic elements in soils with which children have regular contact can provide valuable information to support health risk assessment. It is also important to engage schoolchildren with soil science so that they become well-informed citizens. The Soils in Scottish Schools project involved pupils across Scotland in the collection of soil from school grounds for determination of copper, lead and zinc. Samples were subjected to microwave-assisted aqua-regia digestion to determine pseudototal analyte concentrations. The simplified bioaccessibility extraction test was applied to estimate bioaccessibility. Analysis was performed by inductively coupled plasma mass spectrometry. Pseudototal analyte concentrations varied widely: Cu 15.6–220 mg∙kg−1; Pb 24.6–479 mg∙kg−1 and Zn 52.5–860 mg∙kg−1. Higher concentrations were measured in urban areas, which were historically home to heavy manufacturing industries, with lower concentrations in soils from more rural schools. Bioaccessible analyte concentrations also varied widely (Cu 3.94–126 mg∙kg−1; Pb 6.29–216 mg∙kg−1 and Zn 4.38–549 mg∙kg−1) and followed similar trends to pseudototal concentrations. None of the elements studied posed a significant health risk to children through accidental soil ingestion whilst at play during breaks in the school day, although the relatively high bioaccessible levels of lead at some locations are worthy of further investigation.

Blood Pressure and Oxidative Stress among U.S. Adults Exposed to Lead in Military Environments-A Preliminary Study

In this cross-sectional study, lead exposure among those with a history in military environments was examined. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) are clinical markers of blood pressure, while gamma-glutamyl transferase (GGT) is a marker of oxidative stress. These markers and their effects on those exposed to military environments were explored using National Health and Nutrition Examination Survey (NHANES) data from 2009 to 2016. Mean SBP and GGT were significantly elevated in those exposed to military environments, with a moderately significant association existing between blood lead levels (BLLs) and SBP. More attention must be given to lead exposure in military environments to mitigate the risk of exposure.

Soil Contamination by a Lead Smelter in Brazil in the View of the Local Residents

A primary lead smelter operated in Santo Amaro City in Brazil from 1960 to 1993, leaving approximately 500,000 tons of industrial dross containing 2–3% of lead and other toxic elements that contaminated the industry grounds and the urban environment. This study aimed to present the local residents’ perception towards soil contamination by the smelter. In a cross-sectional study, 208 residents from randomly selected households were interviewed about dross hazards and proposals for its management. A city map depicts the distribution and concentration of lead, cadmium, arsenic, zinc, nickel, and antimony, measured in the soil of the 39 households with visible smelter dross. Only one site complies with the soil quality reference values; 27 (69.2%) call for preventive measures, and 11 (28.2%) require intervention. The smelter dross continues widely spread over the city. Thirty (76.9%) out of the 39 residents were able to recognize the smelter dross on household surroundings. However, this ability was not associated with the concentrations of toxic elements in the soil of their residences and surroundings. The smelter and the local Prefecture were most frequently held liable for taking soil cleanup actions. The most frequently (38.0%) cited solution for managing the dross found in the households was “to provide the residents with information about health risks related to the dross”.