Agency For Toxic Substances And Disease Registry Research Articles

Arsenic Contamination Needs Serious Attention: An Opinion and Global Scenario

Arsenic (As) contamination is a serious global concern, polluting our natural resources, including water and soil, and posing a danger to the environment and public health. Arsenic is present in the groundwater of several countries and this contaminated water is used for irrigation, drinking, and food preparation, which poses the greatest threat to public health. Nearly 106 countries are affected by groundwater arsenic contamination and an estimated 230 million individuals worldwide are exposed to its adverse health effects, including increased cancer risks, associated cardiovascular disease and diabetes, skin lesions, neurological effects, kidney damage, and foetal or cognitive-development-related complications. Arsenic is highly toxic and ranked first in the priority list of ATSDR (Agency for Toxic Substances and Disease Registry, 2022) and among the 10 chemicals of major public health concern on the World Health Organization (WHO) list. The maximum permissible level of arsenic in drinking water has been established at 10 µg/L by WHO, as well as by the Environmental Protection Agency (EPA) and European Union (EU). These regulatory standards underscore the gravity of the problem, and actions to prioritise the development of effective detection, mitigation strategies, and collaborative initiatives are necessary. This opinion article covers (i) arsenic footprints—global scenario and impact, (ii) awareness and education and (iii) mitigation approaches (detection and removal strategies) and future perspectives, which collectively will help in controlling and preventing As contamination of our global water resources. Regulatory and legislative bodies and development agencies are crucial for raising awareness and countering this alarming concern by implementing collaborative actions to protect our environment and public health and to provide safe drinking water for all.

Hydrogeochemical characterization and non-carcinogenic health risk assessment of fluoride and nitrate-affected groundwater in northern parts of Tumkur district, Karnataka, India

Groundwater contamination from geogenic and anthropogenic sources is a significant concern for the public health across the globe. In India, fluoride and nitrate contamination are the most prevalent contaminants in the groundwater. This study evaluated groundwater quality in four over-exploited sub-districts of Tumkur district in Karnataka by collecting 143 samples from post and pre-monsoon seasons and using different hydrogeochemical, statistical and bivariate graphical approaches. Comparison with Drinking Water Standard guidelines revealed elevated levels of fluoride, nitrate, and total dissolved solids (TDS), rendering the groundwater unsuitable for drinking. According to Chadha’s diagram, the predominant groundwater type is Na-Cl, and Gibbs diagram suggested the influence of rock dissolution and weathering. Bivariate plots indicated that hydrogeochemical characteristics were primarily influenced by silicate weathering of minerals, cation ion exchange processes, and anthropogenic factors. A non-carcinogenic health risk assessment was conducted using two different hazard index (HI) approaches from United States Environmental Protection Agency (USEPA) and Agency for Toxic Substances and Disease Registry (ATSDR). It was found that health risk associated with fluoride is more significant than the health risk from nitrate, with children being the most affected, followed by adolescents and adults. A holistic approach to assess cumulative health risks from fluoride and nitrate contamination in groundwater, as demonstrated in this study, promotes the synergistic advancement of SDG 3: Good health and well-being and SDG 6: Clean water and sanitation.

Camp Lejeune Marine Cancer Risk Assessment for Exposure to Contaminated Drinking Water From 1955 to 1987

This study utilizes guidance from the United States Environmental Protection Agency (USEPA) and the Agency for Toxic Substances and Disease Registry (ATSDR) to calculate the cancer risk to United States Marines who were exposed to carcinogens in drinking water at Marine Corps Base Camp Lejeune. Camp Lejeune is a 233-square-mile Marine Corps training facility in North Carolina. From 1953 to 1987, nearby dry cleaners, landfills, and underground storage tanks contaminated drinking water systems that served Camp Lejeune (ATSDR, 2017). Some of the most toxic contaminants found in the drinking water modeled by ATSDR include benzene, tetrachloroethylene (PCE), trichloroethylene (TCE), trans-1,2-dichloroethylene (DCE), and vinyl chloride (VC). ATSDR utilized MODFLOW and EPANET modeling software to determine the level of contamination in the three main drinking water systems at Camp Lejeune: Tarawa Terrace, Holcomb Boulevard, and Hadnot Point. This paper presents an application of methodology to quantify cancer risk for the Marines who lived and served at Camp Lejeune from 1953 to 1987 using ATSDR’s health assessment, chemical contaminant modeling, and USEPA methodology. While VC and TCE were found to be the main risk drivers, benzene and PCE also contributed to the cumulative cancer risk. This analysis shows (1) That the cancer risk was greatest during the 1970s and 1980s and (2) that the inhalation exposure pathway had the greatest contribution to overall cancer risk followed by ingestion, with the smallest contribution from dermal absorption.

One Health assessment of persistent organic chemicals and PFAS for consumption of restored anadromous fish

Abstract Background Restoration efforts have led to the return of anadromous fish, potential source of food for the Penobscot Indian Nation, to the previously dammed Penobscot River, Maine. Objective U.S. Environmental Protection Agency (EPA), Penobscot Indian Nation’s Department of Natural Resources (PINDNR), and Agency for Toxic Substances and Disease Registry (ATSDR), measured contaminants in six species of anadromous fish. Fish tissue concentrations were then used, along with exposure parameters, to evaluate potential human and aquatic-dependent wildlife risk. Methods PINDNR collected, filleted, froze, and shipped fish for analysis of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), dioxins/furans, and per- and polyfluoroalkyl substances (PFAS). Contaminant levels were compared to reference doses (where possible) and wildlife values (WVs). Results Chemical concentrations ranged from 6.37 nanogram per gram (ng/g) wet weight (ww) in American Shad roe to 100 ng/g ww in Striped Bass for total PCBs; 0.851 ng/g ww in American Shad roe to 5.92 ng/g ww in large Rainbow Smelt for total PBDEs; and 0.037 ng/g ww in American Shad roe to 0.221 ng/g ww in Striped Bass for total dioxin/furans. PFAS concentrations ranged between 0.38 ng/g ww of PFBA in Alewife to 7.86 ng/g ww of PFUnA in Sea Lamprey. Dioxin/furans and PFOS levels indicated that there are potential human health risks. The WV for mink for total PCBs (72 ng/g) was exceeded in Striped Bass and the WV for Kestrel for PBDEs (8.7 ng/g) was exceeded in large Rainbow Smelt. Mammalian wildlife consuming Blueback Herring, Striped Bass, and Sea Lamprey may be at risk based on PFOS WVs from Canada. Impact Anadromous fish returning to the Penobscot River potentially could represent the restoration of a major component of tribal traditional diet. However, information about contaminant levels in these fish is needed to guide the tribe about consumption safety. Analysis of select species of fish and risk calculations demonstrated the need for a protective approach to consumption for both humans and wildlife. This project demonstrates that wildlife can also be impacted by contamination of fish and their risks can be as great or greater than those of humans. A One Health approach addresses this discrepancy and will lead to a healthier ecosystem.

Heavy Metals in Follicular Fluid Affect the Ultrastructure of the Human Mature Cumulus-Oocyte Complex.

It is known that exposure to heavy metal such as lead (Pb) and cadmium (Cd) has several adverse effects, particularly on the human reproductive system. Pb and Cd have been associated with infertility in both men and women. In pregnant women, they have been associated with spontaneous abortion, preterm birth, and impairment of the development of the fetus. Since these heavy metals come from both natural and anthropogenic activities and their harmful effects have been observed even at low levels of exposure, exposure to them remains a public health issue, especially for the reproductive system. Given this, the present study aimed to investigate the potential reproductive effects of Pb and Cd levels in the follicular fluid (FF) of infertile women and non-smokers exposed to heavy metals for professional reasons or as a result of living in rural areas near landfills and waste disposal areas in order to correlate the intrafollicular presence of these metals with possible alterations in the ultrastructure of human cumulus-oocyte complexes (COCs), which are probably responsible for infertility. Blood and FF metals were measured using atomic absorption spectrometry. COCs corresponding to each FF analyzed were subjected to ultrastructural analyses using transmission electron microscopy. We demonstrated for the first time that intrafollicular levels of Pb (0.66 µg/dL-0.85 µg/dL) and Cd (0.26 µg/L-0.41 µg/L) could be associated with morphological alterations of both the oocyte and cumulus cells' (CCs) ultrastructure. Since blood Cd levels (0.54 µg/L-1.87 µg/L) were above the current reference values established by the guidelines of the Agency for Toxic Substances and Disease Registry (ATSDR) and the Environmental Protection Agency (EPA) (0.4 µg/L), whereas blood Pb levels (1.28 µg/dL-3.98 µg/dL) were below the ATSDR reference values (≤5 µg/dL), we believe that these alterations could be due especially to Cd, even if we cannot exclude a possible additional effect of Pb. Our results highlighted that oocytes were affected in maturation and quality, whereas CCs showed scarcely active steroidogenic elements. Regressing CCs, with cytoplasmic alterations, were also numerous. According to Cd's endocrine-disrupting activity, the poor steroidogenic activity of CCs might correlate with delayed oocyte cytoplasmic maturation. So, we conclude that levels of heavy metals in the blood and the FF might negatively affect fertilization, embryo development, and pregnancy, compromising oocyte competence in fertilization both directly and indirectly, impairing CC steroidogenic activity, and inducing CC apoptosis.

Biomonitoring equivalents for perfluorooctanoic acid (PFOA) for the interpretation of biomonitoring data

BackgroundPerfluorooctanoic acid (PFOA) is detected in the blood of virtually all biomonitoring study participants. Assessing health risks associated with blood PFOA levels is challenging because exposure guidance values (EGVs) are typically expressed in terms of external dose. Biomonitoring equivalents (BEs) consistent with EGVs could facilitate health-based interpretations. ObjectiveTo i) derive BEs for serum/plasma PFOA corresponding to non-cancer EGVs of the U.S. Environmental Protection Agency (U.S. EPA), the Agency for Toxic Substances and Disease Registry (ATSDR) and Health Canada, and ii) compare with PFOA concentrations from national biomonitoring surveys. MethodsStarting from EGV points of departure, we employed pharmacokinetic data/models and uncertainty factors. Points of departure in pregnant rodents (U.S. EPA 2016, ATSDR) were converted into fetus and pup serum concentrations using an animal gestation/lactation pharmacokinetic model, and equivalent human fetus and child concentrations were converted into BEs in maternal serum using a human gestation/lactation model. The point of departure in adult rodents (Health Canada) was converted into a BE using experimental data. For epidemiology-based EGVs (U.S. EPA 2023, draft), BEs were directly based on epidemiological data or derived using a human gestation/lactation pharmacokinetic model. BEs were compared with Canadian/U.S. biomonitoring data. ResultsNon-cancer BEs (ng/mL) were 684 (Health Canada, 2018) or ranged from 15 to 29 (U.S. EPA, 2016), 6–10 (ATSDR, 2021) and 0.2–0.8 (U.S. EPA, 2023, draft). Ninety-fifth percentiles of serum levels from the 2018–2019 Canadian Health Measures Survey (CHMS) and the 2017–2018 National Health and Nutrition Examination Survey (NHANES) were slightly below the BE for ATSDR, and geometric means were above the non-cancer BEs for the U.S. EPA (2023, draft). ConclusionNon-cancer BEs spanned three orders of magnitude. The lowest BEs were for EGVs based on developmental endpoints in epidemiological studies. Concentrations in Canadian/U.S. national surveys were higher than or close to BEs for the most recent non-cancer EGVs.

Dietary exposure to cadmium from six common foods in the United States.

Recently, the United States (US) Food and Drug Administration (FDA) launched a Closer to Zero Action Plan to assess the risks of and develop action levels for certain heavy metals in food including cadmium (Cd). The problem of foodborne metal contamination has taken on new urgency, thanks in part to a 2021 US Congressional Report detailing high levels of metals found in infant food. Our risk assessment aids this FDA Action Plan by estimating the American population's Cd exposures in food, by age group and consumption patterns of certain high-risk foods; and by determining circumstances in which exposures exceed tolerable daily intakes developed by policymaking groups in the US and worldwide. We found that the age groups 6-24 months and 24-60 month old are the most highly exposed to Cd in common foodstuffs. American infants and young children of these age groups who regularly consumed rice, spinach, oats, barley, potatoes, and wheat had mean Cd exposures exceeding maximum tolerable intake level was set by the Agency for Toxic Substances and Disease Registry (ATSDR). We have identified age groups at highest potential risk, and therefore of interest for developing food safety policies to improve safety of commercial food for children.

Association Between Social Vulnerability Index and Mortality Following Acute Myocardial Infarction in the US Counties

Social determinants of health (SDOH) play a major role in cardiovascular outcomes. The social vulnerability index (SVI) is a tool designed by the Center for Disease Control (CDC) to measure a community's vulnerability to respond and recover from disasters. The parameters of SVI can be used to gauge social disparities amongst different US counties and its association with acute myocardial infarction (AMI) related to age- adjusted mortality rate (AAMR) by using the multiple causes of death database from CDC, Prevention's Wide-Ranging Online Data for Epidemiological Research (WONDER 2016-2020) and Agency for Toxic Substances and Disease Registry (ATSDR). We used segmented regression models to evaluate the association between quintiles of SVI scores and AAMR using STATA. A total of 2908 of 3289 US counties were used in the analysis. The mean AAMR was 89.3 per 100,000 (95% CI: 87.1-91.5) from 2016 to 2020. US counties with higher SVI were associated with higher AMI-related age-adjusted mortality when compared to counties with lower SVI. Counties with the highest SVI and AAMR were in the mid-western and southern states The findings of our study can guide focused care for a uniform upliftment of CV health across the nation by identifying the distribution of socio-economically disadvantaged counties.•Does the social vulnerability index affect Acute Myocardial Infarction (AMI) related mortality in US counties?•US counties with higher SVI were associated with higher AMI-related age-adjusted mortality when compared to counties with lower SVI.

Analysis of Ambient Air Mercury Levels in The Mercury Laboratory and Metrology Centre for Environmental Quality Instrumentation Standardization

Today the use of heavy metals can be found in almost all aspects of life. However, the use of heavy metals causes a process of bioaccumulation of toxins from heavy metals into the body. One type of heavy metal that is very toxic is Mercury (Hg). According to the list of hazardous substances published by the Agency for Toxic Substances and Disease Registry (ATSDR), mercury occupies the third position among 275 substances harmful to human health. The mercury and metrology laboratory is a laboratory that functions to test mercury levels in both water, soil and air matrix samples. In carrying out a test or measurement of Mercury levels, employees at the Mercury and Metrology Laboratory of Centre for Environmental Quality Instrumentation Standardization (PSIKLH) always use Mercury in the process, so there is a possibility that the air in the Mercury and Metrology laboratory of PSIKLH is contaminated with Mercury because of the activities in it. That is the reason of researchers to test mercury levels in the ambient air around the Mercury laboratory and Metrology PSIKLH. This study aims to determine the level of mercury in the ambient air around the mercury and metrology laboratory of PSIKLH. The method used in this study is a quantitative analysis method using the Mercury Analyzer WA-5F from Nippon Instruments Corporation (NIC) which includes curve making, sampling, and measuring mercury levels in the sample. This research was conducted at the Mercury and Metrology Laboratory of PSIKLH. Based on research that was conduct, it shows that the highest concentration of mercury in the ambient air around the PSIKLH Mercury and Metrology Laboratory is found in the Atomic Absorption Spectrophotometer (AAS) room, the sampling equipment room, and the Hg tool room. Mercury levels contained in the three rooms were more than 0.01 mg/m3. However, mercury levels in the Mercury and Metrology Laboratory are still classified as normal because they have not passed the threshold of 0.05 mg/m3.

Arsenic in Drinking Water and Diabetes.

Arsenic is ubiquitous in soil and water environments and is consistently at the top of the Agency for Toxic Substances Disease Registry (ATSDR) substance priority list. It has been shown to induce toxicity even at low levels of exposure. One of the major routes of exposure to arsenic is through drinking water. This review presents current information related to the distribution of arsenic in the environment, the resultant impacts on human health, especially related to diabetes, which is one of the most prevalent chronic diseases, regulation of arsenic in drinking water, and approaches for treatment of arsenic in drinking water for both public utilities and private wells. Taken together, this information points out the existing challenges to understanding both the complex health impacts of arsenic and to implementing the treatment strategies needed to effectively reduce arsenic exposure at different scales.

Socioeconomic vulnerability and the risk of genitourinary cancer mortality among United States counties.

116 Background: The impact of socioeconomic status on genitourinary (GU) cancer mortality in the United States (US) is unclear. Hence, we evaluated the association of the socioeconomic status with GU cancer mortality across the US counties. Methods: County-level age-adjusted mortality rates (AAMR) per 100,000 person-years (PY) for populations diagnosed with GU cancers were abstracted from the wide-ranging online data for epidemiological research (WONDER) database. The agency for toxic substances and disease registry (ATSDR) was queried to obtain county-level social vulnerability indices from 2014-2018. Percentile ranking scores (PRS: ranging from 0-1) were computed for each US county and further categorized into quartiles (Q: 1st: 0-0.25 [least vulnerable]; 4th: 0.75-1.00 [most vulnerable]). AAMRs were then linked with quartile rankings. A population-weighted, Poisson regression analysis was conducted to compute rate ratios (RR) of AAMRs between 4th and 1st Q with the corresponding 95% confidence intervals (CI). Results: A total 3142 US counties were included in this analysis. The AAMR for GU cancers was 22.6 overall deaths (OD) and 4.20 premature deaths (PD; defined as death at age <65 years) per 100,000 PY. GU cancer-related mortality increased in a stepwise fashion from the 1st Q to the 4th Q (OD: 21.6 vs 24.1; PD: 3.48 vs 5.19). In terms of OD by specific GU cancers, significantly higher AAMRs were observed in the 4th Q compared to the 1st Q for patients with prostate cancer (RR; 1.19 [95% CI;1.14-1.24]), and renal cell carcinoma (RCC; 1.12 [1.04-1.21]) but not for those with lower urothelial tract cancers (0.92 [0.87-0.96]). Among subgroups, non-Hispanic Blacks (1.19 [1.07-1.33]), and Hispanics (1.28 [1.08-1.51]) with prostate cancer and men with RCC (1.11; 1.03-1.19) in the 4th Q experienced significantly higher overall mortality when compared to those in the 1st Q. With regards to PD, significantly higher AAMRs were observed in the 4th Q vs 1st Q for patients with prostate cancer (1.54 [1.34-1.77]), and RCC (1.28 [1.12-1.45]). Consistently, men with RCC in the 4th Q also experienced higher premature mortality when compared to the 1st Q. Sparsity of mortality data among different ethnic/racial subgroups across the US counties precluded any formal assessment of disparity by specific GU cancers. A sensitivity analysis, conducted using the weighted linear regression approach, showed consistent results. Conclusions: Population level data suggest that socially vulnerable populations, especially Non-Hispanic Black and Hispanic men with prostate cancer, and men with renal cell carcinoma may be at an increased risk of cancer-related mortality. Hence, there is a dire need to address this mortality gap across different socioeconomic subgroups to ensure health-care equity. Investigations at the patient level are required to further ascertain these findings.

Social vulnerability and gastrointestinal cancer mortality among United States counties.

499 Background: The impact of socioeconomic status on gastrointestinal (GI) cancer mortality in the United States (US) is not well-established. We hypothesized that socially vulnerable populations have disproportionately higher mortality rates. Hence, we assessed the association of the social vulnerability index (SVI) with GI cancer mortality across US counties. Methods: Social vulnerability indices were obtained from the agency for toxic substances and disease registry (ATSDR) from 2014-2018 to compute percentile ranking scores (PRS: ranging from 0-1) for each US county. PRS were further categorized into quartiles (Q: 1st: 0-0.25 [least vulnerable]; 4th:0.75-1.00 [most vulnerable]). The wide-ranging online data for epidemiological research (WONDER) database was queried to abstract county-level age-adjusted mortality rates (AAMR) per 100,000 person-years (PY) for populations diagnosed with GI cancers. AAMRs were then linked with quartile rankings. Rate ratios (RR) of AAMRs between 4th and 1st Q were subsequently estimated with 95% confidence intervals using population-weighted, Poisson regression. Results: A total of 3142 counties were included in this analysis. The AAMR for overall deaths (OD) and premature deaths (PD; defined as death at age <65) in the GI cancer population was 53.8 and 17.7 per 100,000 PY. A gradient increase in GI cancer-related mortality was observed from 1st Q to 4th Q (OD: 49.2 vs 59.3; PD: 14.1 vs 21.3). This stepwise increase in AAMR over the quartiles was consistent across gender, different racial/ethnic subgroups, and rural/urban categories of counties. The AAMRs for OD were significantly higher in the 4th Q as compared to the 1st Q for gastric (RR: 1.67 [95% CI, 1.51-1.86]), hepatocellular including intrahepatic biliary (1.52 [1.45-1.61]), colorectal (1.21 [1.16-1.26]) and biliary (1.17 [1.06-1.28]) cancer. Similarly, significantly higher AAMRs for PD were observed in 4th Q vs1st Q for gastric (1.81 [1.60-2.05]), hepatocellular including intrahepatic biliary (1.78 [1.58-2.00]), biliary (1.64 [1.35-1.99]), colorectal (1.29 [1.21-1.39]) and pancreatic (1.16 [1.07-1.25]) cancer. However, no significant differences were observed for esophageal and small intestinal cancers. Men with gastric (1.58 [1.41-1.78]) and hepatocellular cancer (1.54 [1.43-1.66]), non-Hispanic Black population (1.54 [1.31-1.80]) with hepatocellular cancer, and Hispanic population with colorectal cancer (1.50 [1.31-1.72]) were observed to have higher overall mortality in the 4th Q compared to the 1st Q. The findings were similar for premature mortality. Conclusions: Population-level data suggests that the US counties with higher socio-economic adversities may be at an increased risk of GI cancer-related mortality. Investigations using patient-level data are required to probe the impact of socioeconomic vulnerabilities on cancer-related mortality.

Predictors of Evacuation Rates during Hurricane Laura: Weather Forecasts, Twitter, and COVID-19

Abstract Machine learning was applied to predict evacuation rates for all census tracts affected by Hurricane Laura. The evacuation ground truth was derived from cellular telephone–based mobility data. Twitter data, census data, geographical data, COVID-19 case rates, the social vulnerability index from the Centers for Disease Control and Prevention (CDC)/Agency for Toxic Substances and Disease Registry (ATSDR), and relevant weather and physical data were used to do the prediction. Random forests were found to perform well, with a mean absolute percent error of 4.9% on testing data. Feature importance for prediction was analyzed using Shapley additive explanations and it was found that previous evacuation, rainfall forecasts, COVID-19 case rates, and Twitter data rank highly in terms of importance. Social vulnerability indices were also found to show a very consistent relationship with evacuation rates, such that higher vulnerability consistently implies lower evacuation rates. These findings can help with hurricane evacuation preparedness and planning as well as real-time assessment. Significance Statement This study evaluates the usefulness of Twitter data, COVID-19 case rates, and the social vulnerability index from the Centers for Disease Control and Prevention/Agency for Toxic Substances and Disease Registry in predicting evacuation rates during Hurricane Laura, in the context of other relevant geographic, and weather-related variables. All three are found to be useful, to different extents, and this work suggests important directions for future research in understanding the reasons behind their relevance to predicting evacuation rates.

Arsenic exposure induces urinary metabolome disruption in Pakistani male population

Millions of people are at risk of consuming arsenic (As) contaminated drinking water in Pakistan. The current study aimed to investigate urinary arsenic species [iAsIII, iAsV, dimethylarsinic acid (DMA), methylarsonic acid (MMA)] and their potential toxicity biomarkers (based on urinary metabolome) in order to characterize the health effects in general adult male participants (n = 588) exposed to various levels of arsenic in different floodplain areas of Pakistan. The total urinary arsenic concentration (mean; 161 μg/L) of studied participants was lower and/or comparable than those values reported from other highly contaminated regions, but exceeded the Agency for Toxic Substances and Disease Registry (ATSDR) limits. For all the participants, the most excreted species was DMA accounting for 65% of the total arsenic, followed by MMA (20%) and iAs (16%). The percentage of MMA detected in this study was higher than those of previously reported data from other countries. These results suggested that studied population might have high risk of developing arsenic exposure related adverse health outcomes. Furthermore, random forest machine learning algorithm, partial correlation and binary logistic regression analysis were performed to screen the arsenic species-related urinary metabolites. A total of thirty-eight metabolites were extracted from 2776 metabolic features and identified as the potential arsenic toxicity biomarkers. The metabolites were mainly classified into xanthines, purines, and amino acids, which provided the clues linking the arsenic exposure with oxidative stress, one-carbon metabolism, purine metabolism, caffeine metabolism and hormone metabolism. These results would be helpful to develop early health warning system in context of arsenic exposure among the general populations of Pakistan.

Cadmium dietary exposure assessment in the adult population and pre-school children in the Republic of Serbia

Cadmium (Cd) is a toxic metal, present in all matrices of the environment and a common food contaminant. Human exposure to it may elicit many diverse health impairments. The aim of this study was to assess the dietary exposure to Cd for the adult population and preschool children in Serbia using probabilistic methodology. We measured Cd in 11,227 food samples belonging to 50 food items on the Serbian market. Cd was detected in 90% of the tested food items, and in 30.8% of the overall tested samples. The food item that contributed the most to total dietary Cd intake was potatoes (median Cd concentration of 7 ng/g) in adults, and fruit and vegetable juices in children (median Cd concentration of 19 ng/g). Weekly Cd intake shown as 50th and 95th percentiles were 2.54 and 4.74 µg/kg bw in the adult population, and 3.29 and 4.93 µg/kg bw in children. The results of this study are rather preliminary and should be considered as an indication of the need for further, more refined research, which would contribute to a more realistic risk assessment as a high-priority approach, especially in the case of vulnerable subpopulations such as children. Abbreviations: AT SDR: Agency for Toxic Substances and Disease Registry; EEA: European Environment Agency; EFSA: European Food Safety Authority; FAO/WHO: Food and Agriculture Organization/World Health Organization; HI: hazard index; IARC: International Agency for Research on Cancer; JECFA: Joint FAO/WHO Expert Committee on Food Additives; LOD: limit of detection; Cd: cadmium; TWI: tolerable weekly intake; UNEP: United Nations Environment Program; WI: weekly intake

Synthesis of Nanosilica for the Removal of Multicomponent Cd2+ and Cu2+ from Synthetic Water: An Experimental and Theoretical Study.

Copper and cadmium ions are among the top 120 hazardous chemicals listed by the Agency for Toxic Substances and Disease Registry (ATSDR) that can bind to organic and inorganic chemicals. Silica is one of the most abundant oxides that can limit the transport of these chemicals into water resources. Limited work has focused on assessing the applicability of nanosilica for the removal of multicomponent metal ions and studying their interaction on the surface of this adsorbent. Therefore, this study focuses on utilizing a nanosilica for the adsorption of Cd2+ and Cu2+ from water. Experimental work on the single- and multi-component adsorption of these ions was conducted and supported with theoretical interpretations. The nanosilica was characterized by its surface area, morphology, crystallinity, and functional groups. The BET surface area was 307.64 m2/g with a total pore volume of 4.95×10-3 cm3/g. The SEM showed an irregular amorphous shape with slits and cavities. Several Si-O-Si and hydroxyl groups were noticed on the surface of the silica. The single isotherm experiment showed that Cd2+ has a higher uptake (72.13 mg/g) than Cu2+ (29.28 mg/g). The multicomponent adsorption equilibrium shows an affinity for Cd2+ on the surface. This affinity decreases with increasing Cu2+ equilibrium concentration due to the higher isosteric heat from the interaction between Cd and the surface. The experimental data were modeled using isotherms for the single adsorption, with the Freundlich and the non-modified competitive Langmuir models showing the best fit. The molecular dynamics simulations support the experimental data where Cd2+ shows a multilayer surface coverage. This study provides insight into utilizing nanosilica for removing heavy metals from water.

Usability of some woody plants in monitoring and reducing the Mn, Zn, Ba, and Sr concentrations in the air

The advancements worldwide in the last century made air pollution one of the most important problems threatening human health on a global scale. One of the most harmful components of air pollution is heavy metals. For this reason, monitoring and reducing heavy metal pollution has been one of the main research subjects in recent years. In the present study, the accumulation of Mn, Zn, Ba, and Sr, which were included in the preliminary pollutant list by ATSDR (Agency for Toxic Substances and Disease Registry) since they pose a significant threat to human health, by plant species and organ was investigated. As a result of the present study, the highest concentrations were found in the leaves. The most useful species to be utilized in monitoring the change of the concentrations of heavy metals examined here in the air and to reduce the level of pollution were found to be Cotoneaster franchetii and Platycladus orientalis.

Biological and Environmental Sampling at ATSDR PFAS Exposure Assessment Sites

BACKGROUND AND AIM The Agency for Toxic Substances and Disease Registry (ATSDR) conducted biomonitoring exposure assessments (EAs) in communities near U.S. military installations that have documented PFAS in drinking water. PFAS in drinking water were mitigated prior to initiation of the EAs. METHODS EAs were conducted in ten communities using a community sampling design to evaluate PFAS serum concentrations in communities with PFAS in drinking water. PFAS in urine was measured in a subset of participants. PFAS in indoor dust and tap water were evaluated in a subset of households. All participants completed a questionnaire to gather information to characterize exposure and the responses were evaluated to identify demographic and exposure characteristics associated with PFAS levels in serum. RESULTS The relationships between PFAS levels in drinking water and concentrations of PFAS in serum will be presented for two locations, Hampden County Massachusetts and New Castle County Delaware. The primary PFAS elevated in serum included PFHxS, PFOS, and PFOA which were associated with drinking water exposure. PFAS levels in serum were compared to CDC’s National Health and Nutritional Examination Survey (NHANES). Males had higher PFAS serum levels than females at both locations; additional site-specific findings regarding serum levels and demographic and exposure characteristics information will be presented. Dust sampling results indicated that non-drinking water sources of PFAS may contribute to exposure. CONCLUSIONS The results of testing at the PFAS EA locations presented indicate that levels of PFAS in drinking water are associated with increased levels of PFAS in serum. Additional environmental sampling is being conducted in partnership with U.S. EPA in Delaware and Massachusetts to evaluate potential non-drinking water exposures to PFAS. KEYWORDS: Exposure, PFAS The findings and conclusions in this presentation have not been formally disseminated by CDC/ATSDR and should not be construed to represent any agency determination or policy.

Inorganic arsenic contamination and the health of children living near an inactive mining site: northern Thailand.

Arsenic toxicity is a global health problem affecting millions of people. Contamination is caused by arsenic from natural geological sources leaching into aquifers, contaminating drinking water, and may also be caused by mining and other industrial processes. Acute arsenic poisoning is associated with nausea, vomiting, abdominal pain, and severe diarrhea. Chronic arsenic toxicity results in multisystemic diseases leading to central nervous system (CNS) impairments such as cognitive or intellectual deficits in children. Over the past ten years, arsenic contamination has been reported in northern Thailand. The Ministry of Public Health; Thailand, Forensic Science Institute Thammasat University, and the Research Center to Promote Safety and Prevent Injuries in Children at the Ramathibodi Hospital compiled a report on the health impact of the population within a 10 kilometer radius around a mine tailing in the Phichit, Phitsanulok, and Phetchabun Provinces of Thailand. It showed that more than 30 % of children (aged 8-13 years) had higher than normal arsenic contamination levels based on the Agency for Toxic Substances and Disease Registry (ATSDR). After the publication of that report, the mine was temporarily closed in 2016. Based on this data, this research aimed to follow arsenic contamination after the mining operation had stopped operation for three years. The study showed that 4.5 % of school aged children had levels of inorganic arsenic in their urine, higher than the normal range (ATSDR), showing clearly that inorganic arsenic contamination is still above the normal range in children living near an inactive mining site. Therefore, monitoring heavy metal contamination in Thailand and the health effects on vulnerable children who live near mines during regular operation or after being temporarily suspended can prevent and mitigate possible health impacts.

Flooding and emergency department visits: Effect modification by the CDC/ATSDR Social Vulnerability Index

The Centers for Disease Control and Prevention (CDC)/Agency for Toxic Substances and Disease Registry (ATSDR) Social Vulnerability Index (SVI) is a census-based metric that includes 15 socioeconomic and demographic factors split into four themes relevant to disaster planning, response, and recovery. Using CDC/ATSDR SVI, health outcomes, and remote sensing data, we sought to understand the differences in the occurrence of overall and cause-specific emergency department (ED) visits before and after a 2017 flood event in Texas following Hurricane Harvey, modified by different levels of social vulnerability. We used a controlled before-after study design to estimate the association between flooding and overall and cause-specific ED visits after adjusting for the baseline period, seasonal trends, and individual-level characteristics. We estimated rate ratios stratified by CDC/ATSDR SVI quartiles (overall and 4 themes separately) and tested for the presence of effect modification. Positive effect modification was found such that total ED visits from flooded census tracts with moderate, high, and very high levels of social vulnerability were less reduced compared to tracts with the least vulnerability during flooding and the month following the flood event. The CDC/ATSDR SVI socioeconomic status theme, household composition and disability theme, and housing and transportation type theme explained this result. We found predominantly negative effect modification with higher ED visits among tracts with the least vulnerability for ED visits related to insect bites, dehydration, and intestinal infectious diseases.