Semen Uranium Concentrations in Depleted Uranium Exposed Gulf War Veterans: Correlations with Other Body Fluid Matrices.

Environmental metal exposure, as well as dietary metals, may adversely affect semen quality even as others play an essential role in normal spermatogenesis and fertility. Measures of seminal fluid metals have therefore been of high interest in the last several decades but have shown inconsistent results in correlations with some semen quality parameters. As well, environmental metal measures across various body fluid matrices have not been consistently correlated contrary to what one might hypothesize based on a systemic body burden of metal. This may be due to the body fluid matrices assessed and to other differences in laboratory methods and sample preparation. Measures of uranium, a potentially toxic metal in humans, have not previously been reported in the semen of environmentally metal-exposed populations. We report here uranium seminal fluid results and the high correlation of uranium concentrations across several body fluid matrices in a cohort of military veterans exposed to depleted uranium in combat events during the Iraqi Gulf War. These results inform the risk communication conversation for exposed populations and broaden the public health assessments from various exposure scenarios.

Metal Exposure in Veterans With Embedded Fragments From War-Related Injuries: Early Findings From Surveillance Efforts.

OBJECTIVE: To characterize systemic metal exposures from retained fragments in a cohort of war-injured US Veterans enrolled in the Department of Veterans Affairs' Embedded Fragment Registry. METHODS: Five hundred seventy nine registry-enrolled Veterans submitted an exposure questionnaire and urine sample for analyses of 14 metals often found in fragments. Urine metal results were compared with reference values of unexposed populations to identify elevations. RESULTS: 55% of Veterans had normal urine metal values. When observed, tungsten and zinc were the metals most frequently elevated, followed by cobalt; however, cobalt levels were not associated with a fragment source, but with surgical implants present. CONCLUSIONS: Though most metal elevations observed are not significantly outside the normal range, on-going accrual of metal burdens in these Veterans over time recommends continued surveillance which may inform future medical management.

The U.S. Department of Veterans' Affairs depleted uranium exposed cohort at 25 Years: Longitudinal surveillance results.

BACKGROUND: A small group of Gulf War I veterans wounded in depleted uranium (DU) friendly-fire incidents have been monitored for health changes in a clinical surveillance program at the Veterans Affairs Medical Center, Baltimore since 1994. METHODS: During the spring of 2015, an in-patient clinical surveillance protocol was performed on 36 members of the cohort, including exposure monitoring for total and isotopic uranium concentrations in urine and a comprehensive assessment of health outcomes. RESULTS: On-going mobilization of U from embedded fragments is evidenced by elevated urine U concentrations. The DU isotopic signature is observed principally in participants possessing embedded fragments. Those with only an inhalation exposure have lower urine U concentration and a natural isotopic signature. CONCLUSIONS: At 25 years since first exposure to DU, an aging cohort of military veterans continues to show no U-related health effects in known target organs of U toxicity. As U body burden continues to accrue from in-situ mobilization from metal fragment depots, and increases with exposure duration, critical tissue-specific U concentration thresholds may be reached, thus recommending on-going surveillance of this veteran cohort.

Mobilization of Metal From Retained Embedded Fragments in a Blast-Injured Iraq War Veteran.

A frequent comorbidity of traumatic injury due to a blast or explosion, commonly reported in Iraq and Afghanistan veterans, is that of retained embedded fragments typically of unknown content. Because of concerns over both local and systemic health effects related to both the physical presence of and mobilization of materials from embedded fragments, the Department of Veterans Affairs established a surveillance program for this group of veterans. We present here the case of a surveillance-enrolled veteran who submitted: (1) three surgically removed fragments for content analyses, (2) tissue adhered to the fragments for histology and metal concentration evaluation, and (3) pre- and postfragment removal urine samples to assess concentrations of various metals often found in fragments. Results indicate that removed fragments were aluminum-copper alloys. Surrounding tissue analyses revealed elevated concentrations of these metals and evidence of chronic inflammation, but no neoplastic changes. Urine aluminum concentrations, initially elevated compared to normal population values, decreased significantly after fragment removal, illustrating the utility of urine biomonitoring to provide insight into fragment composition. A medical surveillance program integrating fragment composition data, tissue analyses, and repeat urine biomonitoring can help inform the patient-specific medical management of both the local and systemic effects of retained metal fragments.

Significance of dermatologic findings in a cohort of depleted uranium-exposed veterans of Iraqi conflicts.

BACKGROUND: Depleted uranium (DU)-containing weapons have been used in military operations since 1991. There is interest in following veterans who were occupationally exposed to DU by either inhalation or retention of fragments. A cohort of DU-exposed Gulf War I veterans has been followed longitudinally at the Baltimore Veterans Administration Medical Center since 1993. OBJECTIVE: The aim was to monitor chronic dermatological findings associated with occupational DU exposure in the 2013 cohort. METHODS: Thirty-five veterans were evaluated. This study was reviewed and approved by the institutional review board and the Baltimore Veterans Administration Medical Center research service. Depleted uranium exposure was measured using creatinine-adjusted urine uranium concentrations (micrograms of uranium per gram of creatinine [µgU/gCrea]). Detailed medical histories, physical examinations, and exposure histories were performed. RESULTS: Using a cutoff level of 0.1 µgU/gCrea, 11 veterans were placed in the high-uranium exposure group, whereas 23 veterans were placed in the low-uranium exposure group. Retained fragments were documented in 91% of the high-exposure group versus that in 13% of the low-exposure group (P < 0.001), and fragment-related scarring was significantly increased in the high-exposure group (P = 0.002). Other dermatological findings such as dermatitis were also assessed. CONCLUSIONS: Fragment retainment and related scarring was significantly increased in veterans exposed to high levels of DU. Continuous monitoring of this cohort will yield interesting dermatological findings related to DU exposure.

Biologic monitoring and surveillance results for the department of veterans affairs' depleted uranium cohort: Lessons learned from sustained exposure over two decades.

BACKGROUND: A small group of Gulf War I veterans wounded in depleted uranium (DU) friendly fire incidents have been monitored in a clinical surveillance program at the Veterans Affairs Medical Center, Baltimore since 1994. METHODS: An in-patient clinical surveillance protocol was performed on 35 members of the cohort, including exposure monitoring for total and isotopic uranium concentrations in urine and a comprehensive assessment of health outcomes. RESULTS: Although urine U concentrations continue to be elevated in this group, illustrating on-going in situ mobilization of U from embedded fragments, no consistent U-related health effects have been observed. CONCLUSIONS: Now more than 20 years since first exposure to DU, an aging cohort of military veterans continues to show no U-related health effects in known target organs of U toxicity. As tissue concentrations continue to accrue with exposure duration, critical tissue-specific U concentration thresholds may be reached, thus recommending on-going surveillance of this veteran cohort.

Mutagenicity monitoring following battlefield exposures: Longitudinal study of HPRT mutations in Gulf War I veterans exposed to depleted uranium.

A total of 70 military Veterans have been monitored for HPRT T-cell mutations in five separate studies at 2-year intervals over an 8-year period. Systemic depleted uranium (DU) levels were measured at the time of each study by determining urinary uranium (uU) excretion. Each HPRT study included 30-40 Veterans, several with retained DU-containing shrapnel. Forty-nine Veterans were evaluated in multiple studies, including 14 who were in all five studies. This permitted a characterization of the HPRT mutation assay over time to assess the effects of age, smoking and non-selected cloning efficiencies, as well as the inter- and intra-individual variability across time points. Molecular analyses identified the HPRT mutation and T-cell receptor (TCR) gene rearrangement in 1,377 mutant isolates. An unexpected finding was that in vivo clones of HPRT mutant T-cells were present in some Veterans, and could persist over several years of the study. The calculated HPRT mutant frequencies (MFs) were repeatedly elevated in replicate studies in three outlier Veterans with elevated urinary uranium excretion levels. However, these three outlier Veterans also harbored large and persistent in vivo HPRT mutant T-cell clones, each of which was represented by a single founder mutation. Correction for in vivo clonality allowed calculation of HPRT T-cell mutation frequencies (MutFs). Despite earlier reports of DU associated increases in HPRT MFs in some Veterans, the results presented here demonstrate that HPRT mutations are not increased by systemic DU exposure. Additional battlefield exposures were also evaluated for associations with HPRT mutations and none were found.

Mutagenicity monitoring following battlefield exposures: Molecular analysis of HPRT mutations in Gulf War I veterans exposed to depleted uranium.

Molecular studies that involved cDNA and genomic DNA sequencing as well as multiplex PCR of the HPRT gene were performed to determine the molecular mutational spectrum for 1,377 HPRT mutant isolates obtained from 61 Veterans of the 1991 Gulf War, most of whom were exposed to depleted uranium (DU). Mutant colonies were isolated from one to four times from each Veteran (in 2003, 2005, 2007, and/or 2009). The relative frequencies of the various types of mutations (point mutations, deletions, insertions, etc.) were compared between high versus low DU exposed groups, (based on their urine U concentration levels), with HPRT mutant frequency (as determined in the companion paper) and with a database of historic controls. The mutational spectrum includes all classes of gene mutations with no significant differences observed in Veterans related to their DU exposures.

Chapter 4 embedded metal fragments.

The continued evolution of military munitions and armor on the battlefield, as well as the insurgent use of improvised explosive devices, has led to embedded fragment wounds containing metal and metal mixtures whose long-term toxicologic and carcinogenic properties are not as yet known. Advances in medical care have greatly increased the survival from these types of injuries. Standard surgical guidelines suggest leaving embedded fragments in place, thus individuals may carry these retained metal fragments for the rest of their lives. Nursing professionals will be at the forefront in caring for these wounded individuals, both immediately after the trauma and during the healing and rehabilitation process. Therefore, an understanding of the potential health effects of embedded metal fragment wounds is essential. This review will explore the history of embedded fragment wounds, current research in the field, and Department of Defense and Department of Veterans Affairs guidelines for the identification and long-term monitoring of individuals with embedded fragments.

Comparative physicochemical and biological characterization of NIST Interim Reference Material PM2.5 and SRM 1648 in human A549 and mouse RAW264.7 cells.

The epidemiological association between exposure to fine particulate matter (PM2.5) and adverse health effects is well-known. Here we report the size distribution, metals content, endotoxin content, and biological activity of National Institute of Standards and Technology (NIST) Interim Reference Material (RM) PM2.5. Biological activity was measured in vitro by effects on cell viability and the release of four inflammatory immune mediators, from human A549 alveolar epithelial cells or murine RAW264.7 monocytes. A dose range covering three orders of magnitude (1-1000µg/mL) was tested, and biological activity was compared to an existing Standard Reference Material (SRM) for urban PM (NIST SRM 1648). Robust release of IL-8 and MCP-1 from A549 cells was observed in response to IRM PM2.5 exposures. Significant TNF-α, but not IL-6, secretion from RAW264.7 cells was observed in response to both IRM PM2.5 and SRM 1648 particle types. Cytokine or chemokine release at high doses often occurred in the presence of cytotoxicity, likely as a result of externalization of preformed mediator. Our results are consistent with a local cytotoxic and pro-inflammatory mechanism of response to exposure to inhaled ambient PM2.5 and reinforce the continued relevance of in vitro assays for mechanistic research in PM toxicology. Our study furthers the goal of developing reference samples of environmentally relevant particulate matter of various sizes that can be used for hypothesis testing by multiple investigators.

The Gulf War depleted uranium cohort at 20 years: bioassay results and novel approaches to fragment surveillance.

During the 1991 GulfWar, U.S. service members were exposed to depleted uranium (DU) through friendly-fire incidents involving DU munitions and vehicles protected by DU armor. Routes of exposure to DU involved inhalation of soluble and insoluble DU oxide particles, wound contamination, and retained embedded DU metal fragments that continue to oxidize in situ and release DU to the systemic circulation. A biennial health surveillance program established for this group of Veterans by the U.S. Department of Veterans Affairs has shown continuously elevated urine DU concentrations in the subset of veterans with embedded fragments for over 20 years. While the 2011 assessment was comprehensive, few clinically significant U-related health effects were observed. This report is focused on health outcomes associated with two primary target organs of concern for long term effects of this combat-related exposure to DU. Renal biomarkers showed minimal DU-related effects on proximal tubule function and cytotoxicity, but significant biomarker results were observed when urine concentrations of multiple metals also found in fragments were examined together. Pulmonary tests and questionnaire results indicate that pulmonary function after 20 y remains within the clinical normal range. Imaging of DU embedded fragment-associated tissue for signs of inflammatory or proliferative reactions possibly associated with foreign body transformation or with local alpha emissions from DU was also conducted using PET-CT and ultrasound. These imaging tools may be helpful in guiding decisions regarding removal of fragments.

Surveillance for long-term health effects associated with depleted uranium exposure and retained embedded fragments in US veterans.

OBJECTIVE: To ensure that all veterans with retained embedded fragments are properly monitored for potential health effects of embedded materials. METHODS: Urine biomonitoring and health surveillance programs were developed to gather information about health risks associated with chemicals released from embedded fragments. RESULTS: Elevated systemic exposure to depleted uranium (DU) that continues to occur in veterans with DU fragments remains a concern, although no clinically significant DU-related health effects have been observed to date. Other metals and local tissue reactions to embedded fragments are also of concern. CONCLUSIONS: Knowledge gained from these programs will help to develop guidelines for surgical removal of tissue-embedded fragments.

Measures of genotoxicity in Gulf war I veterans exposed to depleted uranium.

Exposure to depleted uranium (DU), an alpha-emitting heavy metal, has prompted the inclusion of markers of genotoxicity in the long-term medical surveillance of a cohort of DU-exposed Gulf War veterans followed since 1994. Using urine U (uU) concentration as the measure of U body burden, the cohort has been stratified into low-u (<0.10 µg U/g creatinine) and high-u groups (≥ 0.10 µg U/g creatinine). Surveillance outcomes for this cohort have historically included markers of mutagenicity and clastogenicity, with past results showing generally nonsignificant differences between low- vs. high-U groups. However, mean hypoxanthine-guanine phosphoribosyl transferase (HPRT) mutant frequencies (MFs) have been almost 50% higher in the high-U group. We report here results of a more comprehensive protocol performed in a 2009 evaluation of a subgroup (N = 35) of this cohort. Four biomarkers of genotoxicity [micronuclei (MN), chromosome aberrations, and MFs of HPRT and PIGA] were examined. There were no statistically significant differences in any outcome measure when results were compared between the low- vs. high-U groups. However, modeling of the HPRT MF results suggests a possible threshold effect for MFs occurring in the highest U exposed cohort members. Mutational spectral analysis of HPRT mutations is underway to clarify a potential clonal vs. a threshold uU effect to explain this observation. This study provides a comprehensive evaluation of a human population chronically exposed to DU and demonstrates a relatively weak genotoxic effect of the DU exposure. These results may explain the lack of clear epidemiologic evidence for U carcinogenicity in humans. Environ. Mol. Mutagen., 2011. © 2011 Wiley-Liss, Inc.

Patch testing with uranyl acetate in veterans exposed to depleted uranium during the 1991 Gulf war and the Iraqi conflict.

BACKGROUND: The Depleted Uranium Follow-Up Program is a clinical surveillance program run by the Baltimore Veterans Affairs Medical Center since 1993 for veterans of the Gulf and Iraqi wars who were exposed to depleted uranium (DU) as a result of "friendly-fire" incidents. OBJECTIVES AND METHODS: In 2009, 40 veterans from this cohort were screened for skin reactivity to metals by patch-testing with extended metal series and uranyl acetate (0.25%, 2.5%, and 25%). A control arm comprised 46 patients without any known occupational exposures to DU who were seen at the University of Maryland Dermatology Clinic for evaluation of allergic contact dermatitis. RESULTS: Excluding irritant reactions, no patch-test reactions to uranyl acetate were observed in the participants. Irritant reactions to DU were more common in the clinic cohort, likely reflective of the demographic differences between the two arms of the study. Biologic monitoring of urine uranium concentrations in the DU program participants with 24-hour urine samples showed evidence of percutaneous uranium absorption from the skin patches. CONCLUSION: We conclude that dermatitis observed in a subset of the veterans was unrelated to their military DU exposure. Our data suggest that future studies of skin testing with uranyl acetate should utilize 0.25%, the least irritating concentration.

Methodology for collecting, storing, and analyzing human milk for volatile organic compounds.

Biomonitoring, or the measurement of environmental chemicals in human tissues and fluids, is used to supplement-and in some cases replace-more traditional exposure assessments which measure chemicals in environmental media. Volatile organic compounds (VOCs) in physiological fluids are biomarkers of exposure that present numerous challenges for sample collection and analysis. To date, a thorough evaluation of methods for collection and analysis of breast milk samples for volatiles has not been conducted. In this paper, we describe the development and validation of methods for collecting, storing, and analyzing 36 volatile organic compounds (VOCs) in breast milk to assess VOC exposure of lactating women and nursing infants. Volatile analyte loss was minimized by collecting and storing samples in containers with small headspace volume resulting in recovery >or=70% for all 10 VOCs detected in most breast milk samples. Potential contamination by chloroform, benzene, toluene, ethylbenzene, xylenes, and methyl-tert-butyl ether was minimized by using specially treated sample collection materials. Method detection limits in the low parts per trillion range were achieved by using solid-phase microextraction headspace sampling, gas chromatography, and selective ion monitoring mass spectrometry. We used this method to analyze 3 mL aliquots of breast milk collected from 12 women and found that 10 of the 36 VOCs were detectable in most samples (median values follow): m/p-xylene, 0.539 ng mL(-1); toluene, 0.464 ng mL(-1); 1,4-dichlorobenzene, 0.170 ng mL(-1); tetrachloroethylene, 0.165 ng mL(-1); o-xylene, 0.159 ng mL(-1); ethylbenzene, 0.0149 ng mL(-1); styrene, 0.129 ng mL(-1); benzene, 0.080 ng mL(-1); chloroform, 0.030 ng mL(-1); and methyl-tert-butyl ether, 0.016 ng mL(-1).

Biological monitoring for depleted uranium exposure in U.S. Veterans.

BACKGROUND: As part of an ongoing medical surveillance program for U.S. veterans exposed to depleted uranium (DU), biological monitoring of urine uranium (U) concentrations is offered to any veteran of the Gulf War and those serving in more recent conflicts (post-Gulf War veterans). OBJECTIVES: Since a previous report of surveillance findings in 2004, an improved methodology for determination of the isotopic ratio of U in urine ((235)U:(238)U) has been developed and allows for more definitive evaluation of DU exposure. This report updates previous findings. METHODS: Veterans provide a 24-hr urine specimen and complete a DU exposure questionnaire. Specimens are sent to the Baltimore Veterans Affairs Medical Center for processing. Uranium concentration and isotopic ratio are measured using ICP-MS at the Armed Forces Institute of Pathology. RESULTS: Between January 2003 and June 2008, we received 1,769 urine specimens for U analysis. The mean urine U measure was 0.009 microg U/g creatinine. Mean urine U concentrations for Gulf War and post-Gulf War veterans were 0.008 and 0.009 microg U/g creatinine, respectively. Only 3 of the 1,700 (0.01%) specimens for which we completed isotopic determination showed evidence of DU. Exposure histories confirmed that these three individuals had been involved in "friendly fire" incidents involving DU munitions or armored vehicles. CONCLUSIONS: No urine U measure with a "depleted" isotopic signature has been detected in U.S. veterans without a history of retained DU embedded fragments from previous injury. These findings suggest that future DU-related health harm is unlikely in veterans without DU fragments.

Depleted uranium exposure and health effects in Gulf War veterans.

Health effects stemming from depleted uranium (DU) exposure in a cohort of Gulf War veterans who were in or on US Army vehicles hit by friendly fire involving DU munitions are being carefully monitored through the Baltimore Veterans Affairs (VA) DU Follow-Up Program initiated in 1993. DU exposure in this cohort has been directly measured using inductively coupled plasma-mass spectrometer (ICP-MS) isotopic analysis for DU in urine specimens. Soldiers with embedded DU fragments continue to excrete elevated concentrations of U in their urine, documenting ongoing systemic exposure to U released from their fragments. Biennial surveillance visits provide a detailed health assessment that includes basic clinical measures and surveillance for early changes in kidney function, an expected target organ for U. Tests also include measurements of genotoxicity and neuroendocrine, neurocognitive and reproductive function. With the exception of the elevated urine U excretion, no clinically significant expected U-related health effects have been identified to date. Subtle changes in renal function and genotoxicity markers in veterans with urine U concentrations greater than 0.1 microg(-1) creatinine, however, indicate the need for continued surveillance of these DU-exposed veterans.

Biological monitoring and surveillance results of Gulf War I veterans exposed to depleted uranium.

OBJECTIVE: To relate medical surveillance outcomes to uranium biomonitoring results in a group of depleted uranium (DU)-exposed, Gulf War I veterans. METHODS: Thirty-two veterans of Gulf War I who were victims of 'friendly fire' involving DU weapons, in whom exposure assessment can accurately be measured, had urine uranium concentrations determined using ICP-MS technology. Clinical laboratory parameters were measured and related to urine uranium concentrations. Data were examined by stratifying the cohort into a low U group, <0.10 mug/g creatinine versus a high U group, >/=0.10 mug/g creatinine and assessing differences between groups. RESULTS: Over a decade after first exposure, soldiers possessing embedded DU fragments continue to excrete elevated concentrations of uranium in urine. No clinically significant uranium related health effects were observed in blood count, blood chemistries including renal markers, neuropsychological measures, and semen quality or genotoxicity measures. Markers of early changes in renal glomerular and tubular function were not statistically different between groups; however, genotoxicity measures continue to show subtle, mixed results. CONCLUSION: Persistent urine uranium elevations continue to be observed more than 12 years since first exposure. Despite this, renal and other clinical abnormalities were not observed, likely due to the 'relatively' low uranium burden in this cohort compared to historical uranium-exposed occupational groups. Continuing surveillance is indicated, however, due to the on-going nature of the exposure. These results are an important finding in light of the on-going controversy regarding health effects observed in soldiers of the Gulf War and other conflicts, whose uranium exposure assessment is unable to be accurately determined.

Prediction of renal concentrations of depleted uranium and radiation dose in Gulf War veterans with embedded shrapnel.

Mobilization of uranium (U) from embedded depleted uranium (DU) metal fragments in Gulf War veterans presents a unique exposure scenario for this radioactive and nephrotoxic metal. In a cohort of exposed veterans, urine U concentrations measured every two years since 1993 persistently range from 10 to over 500 times normal levels, indicating that embedded DU fragments give rise to chronic, systemic exposure to U. Health effects of this exposure are not fully known, but clinical surveillance of these soldiers continues in light of animal studies showing that U released from implanted DU pellets results in tissue accumulation of U. The biokinetic model for uranium recommended by the International Commission on Radiological Protection was used to predict kidney U concentrations and tissue radiation doses in veterans with DU shrapnel based on their urine U excretion. Results suggest that kidney U concentrations in some individuals reached their peak within six years after the war, while in others, concentrations continue to increase and are approaching 1 ppm after 10 y. These results are consistent with urine biomarker tests of renal proximal tubular cell function and cytotoxicity which have shown elevated mean urinary protein excretion indicative of functional effects in veterans with high urine U concentrations (> or =0.10 microg g(-1) creatinine). Predicted lifetime effective radiation dose from DU released to the blood for the highest exposed individual in this cohort was substantially less than the National Council on Radiation Protection (NCRP) limit for occupational exposure. These results provide further support for current health protection guidelines for DU, which are based on the metal's chemical rather than its radiological toxicity. In light of the potential for continued accumulation of U in the kidney to concentrations approaching the traditional guidance level of 3 ppm U, these results indicate the need for continued surveillance of this population for evidence of developing renal dysfunction.

Health effects of depleted uranium on exposed Gulf War veterans: a 10-year follow-up.

Medical surveillance of a group of U.S. Gulf War veterans who were victims of depleted uranium (DU) "friendly fire" has been carried out since the early 1990s. Findings to date reveal a persistent elevation of urine uranium, more than 10 yr after exposure, in those veterans with retained shrapnel fragments. The excretion is presumably from ongoing mobilization of DU from fragments oxidizing in situ. Other clinical outcomes related to urine uranium measures have revealed few abnormalities. Renal function is normal despite the kidney's expected involvement as the "critical" target organ of uranium toxicity. Subtle perturbations in some proximal tubular parameters may suggest early although not clinically significant effects of uranium exposure. A mixed picture of genotoxic outcomes is also observed, including an association of hypoxanthine-guanine phosphoribosyl transferase (HPRT) mutation frequency with high urine uranium levels. Findings observed in this chronically exposed cohort offer guidance for predicting future health effects in other potentially exposed populations and provide helpful data for hazard communication for future deployed personnel.