Joseph A. Caruso

The use of water pipes or hookahs to smoke tobacco formulations has gained great popularity among young people around the world, but the potential health hazards have not yet been adequately evaluated. The complexity of a multi component hookah apparatus, compared with cigarettes and cigars, makes it difficult to study under laboratory conditions. For this reason the detailed study of its components simplify the task. In this study the charcoal, which is traditionally used as the heat source, was analyzed for metal content before and after combustion. Sixteen different hookah charcoals were analyzed representing different compositions and manufacturing processes as well as different geographic origins. ICP-MS was used to measure 24 elements: Na, Mg, Al, K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Sr, Mo, Ag, Cd, Sb, Ba, Tl, Pb, Th, U. The total concentration ranges of toxic elements in native (un-burned) charcoals were: arsenic 14.8–10 300 ng g⁻¹, cadmium 3.3–2100 ng g⁻¹, and lead 95.2–55 600 ng g⁻¹. The mass-loss-corrected content of elements in combusted charcoals shows that most of the metals remain in the ash, with iron, cadmium and lead as exceptions. Because of the high content of arsenic in some samples an extraction and speciation method was developed to quantify four chemical forms of arsenic. Nitric acid, and phosphoric acid were evaluated as extractants used in a heating block, and ascorbic acid was used to minimize oxidation of inorganic As³⁺ to As⁵⁺. Anion exchange chromatography coupled to ICP-MS was used to carry out the separation and quantification of arsenic species. The best conditions in terms of extraction efficiencies and species conservation were 1.2 mol L⁻¹ H₃PO₄, with 0.2 mol L⁻¹ ascorbic acid. As⁵⁺ was the dominant arsenic species in charcoal. Concentrations ranged from 0.08–2.42 mg kg⁻¹, for As³⁺ and 0.46–8.36 mg kg⁻¹ for As⁵⁺. The results show high variation depending on the sample origin and composition. The possibility of volatile cadmium and lead contributions to the primary and second hand smoke by the charcoal are suggested and the high levels of arsenic suggest that for certain charcoals there may be more hazard from them than from the tobacco formulation.

Fluorescent dyes are widely used in the detection of labile (free or exchangeable) Zn²⁺ and Ca²⁺ in living cells. However, their specificity over other cations and selectivity for detection of labile vs. protein-bound metal in cells remains unclear. We characterized these important properties for commonly used Zn²⁺ and Ca²⁺ dyes in a cellular environment. By tracing the fluorescence emission signal along with UV-Vis and size exclusion chromatography-inductively coupled plasma mass spectrometry (SEC-ICP-MS) in tandem, we demonstrated that among the dyes used for Zn²⁺, Zinpyr-1 fluoresces in the low molecular mass (LMM) region containing labile Zn²⁺, but also fluoresces in different molecular mass regions where zinc ion is detected. However, FluoZin™-3 AM, Newport Green™ DCF and Zinquin ethyl ester display weak fluorescence, lack of metal specificity and respond strongly in the high molecular mass (HMM) region. Four Ca²⁺ dyes were studied in an unperturbed cellular environment, and two of these were tested for binding behavior under an intracellular Ca²⁺ release stimulus. A majority of Ca²⁺ was in the labile form as tested by SEC-ICP-MS, but the fluorescence from Calcium Green-1™ AM, Oregon Green® 488 BAPTA-1, Fura red™ AM and Fluo-4 NW dyes in cells did not correspond to free Ca²⁺ detection. Instead, the dyes showed non-specific fluorescence in the mid- and high-molecular mass regions containing Zn, Fe and Cu. Proteomic analysis of one of the commonly seen fluorescing regions showed the possibility for some dyes to recognize Zn and Cu bound to metallothionein 2. These studies indicate that Zn²⁺ and Ca²⁺ binding dyes manifest fluorescence responses that are not unique to recognition of labile metals and bind other metals, leading to suboptimal specificity and selectivity.

The effect of selenium on modulating arsenic cytotoxicity is well known in mammals, but not well understood. Cell cytotoxicity and reactive oxygen spe

In this initial study, the concentrations of eighteen elements (Na, K, Mg, Ca, Al, Fe, V, Cr, Mn, Ni, Cu, Zn, Se, Mo, As, Cd, Sb and Pb) in 12 hookah tobacco formulations (mo'assel) were studied by ICPMS. Eight of these were formulated in the United States, and four were from the Middle East. The analyses were made from two of the hookah compartments; as homogenized material of the hookah samples as received and by separating the received samples into the actual tobacco and a hot water extract that removed as much of the other formulation substances as possible. The extractable portion that represents up to 50% in mass of the total hookah sample is made up of honey/molasses, glycerin, colorants and flavorings, but this study shows the hot water extract to be relatively free of toxic elements. The elemental ranges found for the homogenized hookah mixtures are as follows: V, 0.03–0.16 μg g⁻¹; Cr, 0.15–0.37 μg g⁻¹; Mn 8.82–17.2 μg g⁻¹; Ni, 0.14–0.64 μg g⁻¹; Cu, 0.93–5.67 μg g⁻¹; Zn, 3.51–5.62 μg g⁻¹; As, 0.01–0.04 μg g⁻¹; Se, 0.002–0.014 μg g⁻¹; Mo, 0.05–0.13 μg g⁻¹; Cd, 0.10–0.27 μg g⁻¹ and Pb, −1. Given the very small fraction of trace metals in the extract, most of the metals are contained in the tobacco leaves. It was found that the major variation in the concentrations owe to the geographic production regions; namely the USA and the Middle East. A principal component analysis was performed as an explorative tool, and a good separation was found, when grouping according to preparation by geographic production region. Based on these results the average mass of the more toxic elements (As, Cd, Cr and Pb) present in a hookah smoking portion of about 15 g, is smaller than that contained in a normal cigarette. However, before any true comparisons can be made on the differences between the hookah formulations and actual dryer tobaccos, the temperature at which the smoke is produced, the length of time per smoking session, any possible metal contamination from the apparatus and contamination from the charcoal used to ignite the hookah formulation must be taken into account.

Stroke is the leading cause of adult disability, worldwide. Metalloproteins and metals play key roles in epigenetic events in living organisms, including hypertension, the most important modifiable risk factor for stroke. Thus, metalloproteins may be important target biomarkers for disease diagnosis. The primary goal of this study was to assess metal containing proteins in blood plasma, detected by ICP-MS, followed by ESIMS for peptide/protein identification. We then compared the relative concentration differences between samples from patients with ischemic stroke, hemorrhagic stroke and stroke mimics. In 29 plasma samples (10 stroke mimics, 10 ischemic stroke and 9 hemorrhagic stroke patients) previously collected from patients who presented to the University of Cincinnati Emergency Department within 12 hours of symptom onset for a plasma banking project. For the metal associated protein study, Mg, Mn, Cu, Se concentrations were statistically different when compared between stroke mimics vs. ischemic stroke patients and ischemic stroke patients vs. hemorrhagic stroke patients. Pb concentrations were statistically different when compared between stroke mimics vs. ischemic stroke patients and Mo levels were statistically the same among the three groups. In addition, we also report concentration levels and preliminary correlation studies for total elemental analysis among the three sets of patients. This pilot study demonstrates that mass spectrometry methods may be highly valuable in detecting novel stroke biomarkers in blood plasma. Expanded studies are warranted to confirm these findings.

Stroke is the most common cause of morbidity and death in the Western world, following ischemic heart disease and cancer. Stroke can be of two types, ischemic or hemorrhagic, with ischemic stroke accounting for approximately 85% of the total number of strokes. Well‐recognized environmental risk factors for stroke include hypertension, smoking, diabetes mellitus, atrial fibrillation, and atherosclerosis. Computed tomography (CT) scanning is used to diagnose hemorrhagic stroke but is relatively ineffective and may remain normal in patients with mild ischemic strokes. Magnetic Resonance Imaging (MRI) is more sensitive in detecting ischemia than CT, especially in the diagnosis of mild stroke but it is still not 100% sensitive or precise. A simple and low‐cost, rapid blood test to confirm a clinical and imaging diagnosis of ischemic stroke would be extremely useful. Based on this, the central idea of this paper is to develop a method that would be applicable to a statistically viable sample set to provide candidate biomarkers for distinguishing stroke types. In search of these candidate biomarkers, different analytical separation techniques have been used to screen for major differences in the proteomes of patients plasma samples with proteomics for identification.

Our previous study found that high-molecular-weight selenium (Se) species make up 82% of the total Se in the bean of Se-enriched soybean plants (Chan et al. 2010, Metallomics, 2(2): p. 147–153). The Se species have been commonly seen in other plants in addition to soybean, but their identities remain unresolved. The present study employs a multi-technique metallomics approach to characterize the proteins containing Se in the beans of Se-enriched soybean plants. Two main categories of proteins, maturation proteins and protease inhibitors, were found in Se-containing high-performance liquid chromatography (HPLC) fractions. The proteins were screened by two-dimensional HPLC-inductively coupled plasma mass spectrometry, size-exclusion chromatography, and anion-exchange chromatography, and the Se-containing fractions were then identified by peptide mapping using HPLC-Chip-electrospray ion trap mass spectrometry. Based on the belief that Se goes into proteins through non-specific incorporation, a new method was designed and applied for the Se-containing peptide identification. The Se-containing peptide KSDQSSSYDDDEYSKPCCDLCMCTRS, part of the sequence of protein Bowman–Birk proteinase isoinhibitor (Glycine max), was found in one of the Se-containing fractions. The nutritional value of the Se-containing proteins in Se-enriched soybeans will be an interesting topic for the future studies.