No abstract

Identification and characterization of viable culturable bacteria (VCB) associated with soils from Africa and the Americas are significant for environmental and battlefield security. Such analyses are scarce, and their evaluation using traditional microbiological methods does not fully elucidate the structure and chemotaxonomic characteristics of the microbial community. In this study, matrix-assisted laser desorption time of flight mass spectrometry (MALDI-TOF MS), spectrometry in addition to 16S rRNA sequencing, and diversity indices were employed to characterize VCB and their associated biomarkers. Nineteen genera were identified across all sample locations, but only four (Bacillus, Brevibacillus, Paenibacillus, and Terribacillus) confirmed by ClustalW2 as being 98-99 % similar among locations. Further evaluation of soils showed bacterial diversity (H) of (1.0-8.4), evenness (E H), (0.14-0.72), similarity (Sj), (0.0-0.38), and cfu/g soil (2.5 9 10 1-2.2 9 10 7). Analysis of representative bacteria using MALDI-TOF MS identified biomarkers for the genera Bacillus at m/z 6,778 (75 %), 9,437 (100 %);

We developed and validated a method for the assessment of thirteen separate trace and toxic elements using Inductively Coupled Plasma‐Mass Spectrometry (ICP‐MS). Included elements were as follows: aluminum, chromium, manganese, iron, cobalt, nickel, copper, zinc, arsenic, molybdenum, cadmium, tungsten, and lead. The measurements of all elements in urine samples were conducted using ICAP‐Q ICP‐MS in a single method. The performance characteristics of the assay were determined according to clinical laboratory standards. The assay was linear in the concentration range of 1.0 to 1000.0 µg/liter for all elements. The method was precise and accurate with limits of quantitation of 1 µg/liter for chromium, manganese, cobalt, nickel, copper, cadmium, tungsten, and lead; 2 µg/liter for iron and arsenic; 5 µg/liter for aluminum; and 50 µg/liter for zinc. This method has successfully been used for the assessment of all thirteen elements included in urine and has been shown to be effective as a simple, precise, and sensitive analytical technique for biological monitoring of urine samples. © 2018 by John Wiley & Sons, Inc.

Gulf War I veterans who were victims of depleted uranium (DU) “friendly-fire” incidents have undergone longitudinal health surveillance since 1994. During the spring of 2019, 36 members of the cohort were evaluated with a monitoring protocol including exposure assessment for total and isotopic uranium concentrations in urine and a comprehensive review of health outcomes, including measures of bone metabolism and bone mineral density (BMD) determination. Elevated urine U concentrations were observed in cohort members with retained depleted uranium (DU) shrapnel fragments. In addition, a measure of bone resorption, N-telopeptide, showed a statistically significant increase in those in the high DU subgroup, a finding consistent with a statistically significant decrease in bone mass also observed in this high DU subgroup compared to the low DU subgroup. After more than 25 y since first exposure to DU, an aging cohort of military veterans continues to show few U-related health effects in known target organs of U toxicity. The new finding of impaired BMD in the high DU subgroup has now been detected in two consecutive surveillance visits. While this is a biologically plausible uranium effect, it is not reflected in other measures of bone metabolism in the full cohort, which have largely been within normal limits. However, ongoing accrual of the U burden from fragment absorption over time and the effect of aging further impairing BMD suggest the need for future surveillance assessments of this cohort.

We have developed and validated a method for the simultaneous quantitative measurement of total uranium (TU) and uranium 235U/238U isotopic ratio (UIR) in urine by inductively coupled plasma mass spectrometry (ICP‐MS) using a Thermo Scientific iCAP‐Q instrument. The performance characteristics of the assay were determined to be in compliance with clinical laboratory standards. The assay was linear in the concentration range of 1.0 to 500.0 ng/liter TU. The method was precise and accurate with limits of detection of 2.5 ng/liter for TU and 9.8 ng/liter for UIR. The accuracy was >93% and the coefficient of variation (% CV) was <5.0% for both TU and UIR. All results were within established guidelines and agreed‐upon criteria, and the results fell within the certified range for the reference controls. The method has thus been shown to be effective as a simple, precise, and sensitive analytical technique for testing urine samples. © 2018 by John Wiley & Sons, Inc.