Search

Introduction:To date, all human studies of mass-casualty decontamination for chemical incidents have relied on the collection and analysis of external samples, including skin and hair, to determine decontamination efficacy. The removal of a simulant contaminant from the surface of the body with the assumption that this translates to reduced systemic exposure and reduced risk of secondary contamination has been the main outcome measure of these studies. Some studies have investigated systemic exposure through urinary levels of simulant metabolites. The data obtained in these studies were confounded by high background concentrations from dietary sources. The unmetabolized simulants have never been analyzed in urine for the purposes of decontamination efficacy assessment.Study Objective:Urinary simulant analysis could obviate the need to collect skin or hair samples during decontamination trials and provide a better estimate of both decontamination efficacy and systemic exposure. The study objective therefore was to determine whether gross skin contamination as part of a decontamination study would yield urine levels of simulants sufficient to evaluate systemic availability free from dietary confounders.Methods:In this study, a gas chromatography-tandem mass spectrometry method was developed for the analysis of two chemical simulants, methyl salicylate (MeS) and benzyl salicylate (BeS), in urine. An extraction and sample clean-up method was validated, enabling quantitation of these simulants in urine. The method was then applied to urine collected over a 24-hour period following simulant application to the skin of volunteers.Results:Both MeS and BeS were present in all urine samples and were significantly increased in all post-application samples. The MeS levels peaked one hour after skin application. The remaining urinary levels were variable, possibly due to additional MeS exposures such as inhalation. In contrast, the urinary excretion pattern for BeS was more typical for urinary excretion curves, increasing clearly above baseline from four hours post-dose and peaking between 12.5 and 21 hours, a pattern consistent with dermal absorption and rapid excretion.Conclusion:The authors propose BeS is a useful simulant for use in decontamination studies and that its measurement in urine can be used to model systemic exposures following skin application and therefore likely health consequences.

Electronic cigarettes divide opinions. Some consider them key to reducing smoking incidence while others are concerned over potential for detrimental health consequences. It will take many years to identify the health consequences of e-cigarette use if we rely only upon human data. However, there is a growing body of work using rodent models that inform on these potential toxicities. These studies have focused upon the pulmonary, cardiovascular and central nervous systems. Observations include perturbations of pro-inflammatory, pro-fibrotic and oxidative stress markers, sometimes together with DNA damage and downregulation of DNA repair and antioxidant enzymes. However, the markers affected are often different between studies. A more consistent observation has been the increase in airway hyperresponsiveness, a characteristic of asthma, on exposure to electronic cigarettes, across mouse strains, sex and ages. Detrimental effects in this and other susceptible animal models such as the apolipoprotein E knock-out mouse model of atherosclerosis, suggest greater risk where there is an existing predisposition. Other adverse reactions, including weight loss, oxidative stress and angiogenesis, are reported in animal studies with nicotine-containing devices. These effects remain less severe than cigarette smoke, where investigated. Animal studies have identified therefore that e-cigarettes are potentially hazardous, especially in susceptible populations, nicotine is integral to risk of health effects, but overall e-cigarettes are much less hazardous than cigarettes.

In recent years, reports of lead contamination have dramatically increased in Georgia. Given concerns about the exposure of children to lead (Pb), the National Multiple Indicator Cluster Survey (MICS-2018) included a blood sampling component. The results showed that 41% of the children that participated had blood Pb levels (BLL) ≥ 5 µg/dL and that BLL in children living in Western Georgia were higher than those in Eastern regions. In response to these findings, NCDC implemented written and verbal advice to the families of children who participated in the MICS-2018 on how to reduce Pb exposure. From August 2019 onwards, the state program of clinical follow-up was implemented. The design of this study was a longitudinal study. The intervention of interest was the public health advice and medical follow-up, and the outcome was defined as the difference in BLL between the MICS-2018 survey and the state program follow-up. We observed a significant overall reduction in median BLL between MICS-2018 and state program follow-up in both August 2019 and the latest results (until December 2019). However, we did not observe any significant further reduction between August and the most recent BLL results. In the Georgian setting, written and verbal communication targeting individual households, alongside home visits to the most exposed, effectively reduced BLL in children.

The decontamination of exposed persons is a priority following the release of toxic chemicals. Efficacious decontamination reduces the risk of harm to those directly affected and prevents the uncontrolled spread of contamination. Human studies examining the effectiveness of emergency decontamination procedures have primarily focused on decontaminating skin, with few examining the decontamination of hair and scalp. We report the outcome of two studies designed to evaluate the efficacy of current United Kingdom (UK) improvised, interim and specialist mass casualty decontamination protocols when conducted in sequence. Decontamination efficacy was evaluated using two chemical simulants, methyl salicylate (MeS) and benzyl salicylate (BeS) applied to and recovered from the hair of volunteers. Twenty-four-hour urinary MeS and BeS were measured as a surrogate for systemic bioavailability. Current UK decontamination methods performed in sequence were partially effective at removing MeS and BeS from hair and underlying scalp. BeS and MeS levels in urine indicated that decontamination had no significant effect on systemic exposure raising important considerations with respect to the speed of decontamination. The decontamination of hair may therefore be challenging for first responders, requiring careful management of exposed persons following decontamination. Further work to extend these studies is required with a broader range of chemical simulants, a larger group of volunteers and at different intervention times.

Planning for major incidents involving the release of hazardous chemicals has been informed by a multi-disciplinary research agenda which has sought to inform all aspects of emergency response, but with a focus in recent years on mass casualty decontamination. In vitro and human volunteer studies have established the relative effectiveness of different decontamination protocols for a range of chemical agents. In parallel, a programme of research has focused on communicating with and managing large numbers of contaminated casualties at the scene of an incident. We present an accessible overview of the evidence underpinning current casualty decontamination strategies. We highlight where research outcomes can directly inform response planning, including the critical importance of beginning the decontamination process as soon as possible, the benefits of early removal of contaminated clothing, the evidence under-pinning dry and wet decontamination and how effective communication is essential to any decontamination response. We identify a range of priority areas for future research including establishing the significance of the ‘wash-in’ effect and developing effective strategies for the decontamination of hair. We also highlight several areas of future methodological development, such as the need for novel chemical simulants. Whilst considerable progress has been made towards incorporating research outcomes into operational policy and practice, we outline how this developing evidence-base might be used to inform future iterations of mass casualty decontamination guidance.

The decontamination of exposed persons is a priority following the release of toxic chemicals. Efficacious decontamination reduces the risk of harm to those directly affected and prevents the uncontrolled spread of contamination. Human studies examining the effectiveness of emergency decontamination procedures have primarily focused on decontaminating skin, with few examining the decontamination of hair and scalp. We report the outcome of two studies designed to evaluate the efficacy of current United Kingdom (UK) improvised, interim and specialist mass casualty decontamination protocols when conducted in sequence. Decontamination efficacy was evaluated using two chemical simulants, methyl salicylate (MeS) and benzyl salicylate (BeS) applied to and recovered from the hair of volunteers. Twenty-four-hour urinary MeS and BeS were measured as a surrogate for systemic bioavailability. Current UK decontamination methods performed in sequence were partially effective at removing MeS and BeS from hair and underlying scalp. BeS and MeS levels in urine indicated that decontamination had no significant effect on systemic exposure raising important considerations with respect to the speed of decontamination. The decontamination of hair may therefore be challenging for first responders, requiring careful management of exposed persons following decontamination. Further work to extend these studies is required with a broader range of chemical simulants, a larger group of volunteers and at different intervention times.

Introduction: We aim to study the effect of fatty acid amide hydrolase (FAAH) blockade on bladder hyperactivity and on fatty acid amides levels during cystitis. Material and Methods: Cystitis was induced in female Wistar rats using 5 mg/mL lipopolysaccharide (LPS). Control group were intravesical instilled with saline. LPS and control groups received intravenously (caudal vein) during cystometry: URB 937 (URB; FAAH antagonist) in doses of 0.007, 0.07, 0.7 and 7 mg/kg (cumulative, with 10 minutes interval). Using the maximal effective dose of URB (0.7 mg/kg, see below) animals received 10 uM MJ15 (CB1 receptor antagonist) or 0.3 mg SR144528 /kg (SR; CB2 receptor antagonist). At dose of 7 mg/kg, animals receive 1.4 μg SB366791/kg (SB; TRPV1 antagonist). Control and inflamed (without and with 0.7 and 7 mg/kg URB) group were euthanized and the bladder was harvested for the determination of anandamide (AEA) and palmitoylethanolamide (PEA) by mass spectrometry. Results: Frequency of control was not changed by URB treatment at any dose. LPS increase bladder frequency. 0.007 mg and 0.07 mg URB decrease bladder frequency of LPS-inflamed rats. 0.7 URB reversed LPS-induced bladder hyperactivity. At 7 mg, URB was unable to reverse or reduce LPS-induced bladder hyperactivity. The administration of CB1, CB2 and TRPV1 antagonists did not change the frequency of voiding contractions of naïve animals. CB1 antagonist reversed the effect of 0.7 URB while TRPV1 antagonist reduced the effect of 7 URB. AEA levels increase during inflammation. Treating LPS-inflamed animals with 0.7 mg URB brought AEA levels to control levels. Treating LPS-inflamed animals with 7 mg URB did not change AEA levels, compared to LPS-inflamed animals. PEA levels decrease during inflammation. Treating LPS-inflamed animals with 0.7 mg URB brought AEA levels to control levels. Treating LPS-inflamed animals with 7 mg URB, decreased PEA levels to values similar to the ones observed in LPS- -inflamed animals. Conclusion: During cystitis, the FAAH inhibitor raises the levels of PEA and reverses the urinary frequency by a CB1 receptor- mediated mechanism. When used in very high doses, the FAAH antagonist raises the levels of AEA and increases the urinary frequency by a TRPV1-dependent mechanism. Therefore, the choice of FAAH inhibitor dosage to be used in the clinics should consider the putative effects over the endocannabinoid levels in the system.

Chemical simulants have long been used in human trials of mass decontamination to determine the efficacy of decontamination interventions against more toxic agents. Until now, reliance has mostly been on individual chemicals as surrogates to specific agents (e.g. methyl salicylate for sulphur mustard). A literature review was conducted to identify chemicals that had been previously tested on human volunteers and that represent diverse physicochemical characteristics in order to create a repository for chemical simulants. Of the 171 unique chemicals identified 78 were discounted for the risk they could pose to human volunteers, 39 were deemed suitable for use and a further 54 were considered to be possible simulants but would require further research. Suitable simulants included both solid and liquid chemicals spanning a wide range of physicochemical properties including molecular weight, octanol/ water partition coefficient, vapour pressure and solubility. This review has identified an array of potential simulants suitable for use in human volunteer decontamination studies and is of relevance to future studies on systemic absorption and surface decontamination.

Introduction This project aims to monitor human volunteers as they switch from heavy (>10 cigarette/day) tobacco smoking to electronic cigarette (EC) use. Monitoring of markers will comprise expired carbon monoxide, DNA methylation, oxytocin, cortisol, nicotine cotinine and tobacco specific nitrosamine levels in urine and saliva together with psychometric data. In addition electroencephalography will be used to search for electrical changes in the brain correlated with changes in the above markers after transition to EC use. Methods Volunteers were recruited and consented at St George’s University of London. Volunteers were allowed to select their own EC and e-fluid including nicotine concentration. Blood, saliva, urine and buccal cell samples and questionnaire data (nicotine dependence, withdrawal, anxiety, depression, mood, quality of life and sleep quality) were collected at baseline (day-2 and day-1) and throughout the 28-day EC trial (days 3,21,28) and EEG data (eyes open-eyes fixed-eyes closed, each 3 x 30s) were collected at baseline (day-1) and on EC day 21. Nicotine, cotinine, NNK, NNAL and NNN were determined by UHPLC-HESI-HRMS, 5methyl cytosine by HPLC and oxytocin and cortisol by ELISA. Results Urinary and salivary nicotine, cotinine and tobacco specific nitrosamines and expired carbon monoxide decrease significantly following transition to EC. Behavioural data have revealed modest changes in nicotine craving, nicotine withdrawal symptoms, social anxiety and sleep quality following the transition to e-cigarettes. Preliminary comparison of regional spectral power extracted from EEG data collected pre- and post- transition to e-cigarettes use has identified significant changes in specific spectral bands across the brain. Conclusions Switching to EC quickly induces beneficial changes in exposure to toxicants and psychometrics. Changes in regional spectral power observed by EEG vary will be correlated to these other biomarkers. Funding This work is supported by H2020 funding from the European Union and by a PHE-funded PhD studentship.

Aim To monitor how switching to e-cigarettes from cigarette smoking affects psychometric and clinical parameters and relapse rate over a period of 4 weeks. Methods Heavy smokers (≥10cig/day) attended 6 visits where psychometric parameters associated with craving, nicotine withdrawal symptoms, sleep and quality of life were monitored using well validated questionnaires. Heart rate and blood pressure were also measured at each visit. Visit 1 and 2 were baseline visits where smokers continued to smoke and then asked to quit and transition to e-cigarette use. The subsequent visits occurred 3, 7, 21 and 28 days after the quit date. Compliance was monitored via exhaled CO. Completed participants received weekly questionnaires for 12 months and two follow up calls 6 and 12 months after their final visit to monitor for relapse. Results One month relapse rate amongst eligible participants (n=29) was 28%. At 6 months (n=5), 40% used either e-cigarettes or nothing (non-relapsers) and 60% partially relapsed or were dual users. Repeated measures One-Way ANOVA(n=20) showed a significant effect for parameters: ‘irritability’ (p

Introduction Use of electronic cigarettes (ECs) has increased rapidly since they were introduced in Europe in 2006 especially in the UK. Claims have been made for a role in tobacco harm reduction and smoking cessation. Key to these claims is the ability of EC to maintain nicotine levels to limit cravings, withdrawal and nicotine dependence. Therefore, the aim of the current study is to monitor nicotine intake in heavy smokers (>10 cig/day, n=13 completed) transitioning from cigarette smoking to EC-only use whilst collecting psychometric data on nicotine dependence (Fagerstrom), withdrawal (Minnesota), anxiety, depression and sleep quality. Material and Methods Urine and saliva samples as well as psychometric questionnaire data were collected at baseline (visits 1 and 2) and at days 3, 7, 21 and 28 following start of EC use. An UHPLC-HESI-HRMS method was developed, validated and applied to the determination of nicotine and its main metabolite cotinine in urine and saliva. Results The baseline median (interquartile range) urinary nicotine and cotinine levels were determined as 1534 ng/mg creatinine (317-2478) and 2082 ng/mg creatinine (1727-3632), whereas salivary nicotine and cotinine levels were 145 ng/ml (26-265) and 329 ng/ml (198-440), respectively. One-way repeated measures Anova demonstrated a significant decrease in urinary nicotine and cotinine concentration from baseline at 3 post-transition visits. A significant reduction was also observed in salivary nicotine levels on days 3 and 21 after EC transition and in salivary cotinine levels at each post-transition visit compared to baseline. Both urge and strength of urges to smoke were significantly decreased by 28days compared to baseline. Conclusions These findings offer support that EC can be effective in reducing nicotine consumption and cravings for cigarettes, suggesting the potential use of EC as a smoking cessation tool. However, the inability to achieve levels of nicotine comparable to smokers may contribute to relapse. Funding Statement Funded by European Commission Horizon 2020 programme.

Introduction The aim of this study was to quantify levels of carcinogenic tobacco specific nitrosamines (TSNAs) in human volunteers transitioning from tobacco use to electronic cigarettes (EC). ECs have increased in popularity, with consumers using ECs to aid with smoking cessation, reduce cigarette consumption, or to minimise withdrawal symptoms when smoking but not vaping is prohibited. There has been little investigation into the long term health impacts of ECs, but they are generally considered less toxic than conventional tobacco cigarettes. This is due to the absence or decreased levels of harmful chemicals commonly found in tobacco cigarettes. However, some studies have shown the presence of traces of TSNAs in e-liquid, and the endogenous nitrosation of nicotine to TSNAs in nicotine replacement therapies (NRT). These TSNAs include NNK, NNN, and NNAL, which are potent oesophageal and pulmonary carcinogens. Therefore, inhalation of these compounds may provide an added risk to the use of ECs, when compared to other NRT products. Methods Biofluids have been analysed for TSNAs in the urine and saliva of heavy smokers (>10 cigarettes/day) who quit and transition to EC use for 28 days. A solid phase extraction method using TSNA specific molecular imprinted polymers was used to concentrate samples, which were subsequently analysed using UHPLC-ESI-HRMS. Results Analysis of longitudinal urine and saliva samples (n=13) has shown a decrease in TSNA levels over the period of transition from tobacco use to EC only use. Conclusions The findings are consistent with the notion that substituting conventional cigarettes with ECs significantly lowers exposure to carcinogenic TSNAs. Further work is needed to determine whether TSNAs present in urine and saliva represent continued low level exposure to TSNAs as contaminants in EC or markers of nitrosation. Funding This work is funded by Horizon 2020, and Public Health England

Background Nanomaterial inhalation represents a potential hazard for respiratory conditions such as asthma. Cerium dioxide nanoparticles (CeO2NPs) have the ability to modify disease outcome but have not been investigated for their effect on models of asthma and inflammatory lung disease. The aim of this study was to examine the impact of CeO2NPs in a house dust mite (HDM) induced murine model of asthma. Results Repeated intranasal instillation of CeO2NPs in the presence of HDM caused the induction of a type II inflammatory response, characterised by increased bronchoalveolar lavage eosinophils, mast cells, total plasma IgE and goblet cell metaplasia. This was accompanied by increases in IL-4, CCL11 and MCPT1 gene expression together with increases in the mucin and inflammatory regulators CLCA1 and SLC26A4. CLCA1 and SLC26A4 were also induced by CeO2NPs + HDM co-exposure in air liquid interface cultures of human primary bronchial epithelial cells. HDM induced airway hyperresponsiveness and airway remodelling in mice were not altered with CeO2NPs co-exposure. Repeated HMD instillations followed by a single exposure to CeO2NPs failed to produce changes in type II inflammatory endpoints but did result in alterations in the neutrophil marker CD177. Treatment of mice with CeO2NPs in the absence of HDM did not have any significant effects. RNA-SEQ was used to explore early effects 24 h after single treatment exposures. Changes in SAA3 expression paralleled increased neutrophil BAL levels, while no changes in eosinophil or lymphocyte levels were observed. HDM resulted in a strong induction of type I interferon and IRF3 dependent gene expression, which was inhibited with CeO2NPs co-exposure. Changes in the expression of genes including CCL20, CXCL10, NLRC5, IRF7 and CLEC10A suggest regulation of dendritic cells, macrophage functionality and IRF3 modulation as key early events in how CeO2NPs may guide pulmonary responses to HDM towards type II inflammation. Conclusions CeO2NPs were observed to modulate the murine pulmonary response to house dust mite allergen exposure towards a type II inflammatory environment. As this type of response is present within asthmatic endotypes this finding may have implications for how occupational or incidental exposure to CeO2NPs should be considered for those susceptible to disease. Electronic supplementary material The online version of this article (10.1186/s12989-018-0261-5) contains supplementary material, which is available to authorized users.

Acute inhalation studies are conducted in animals as part of chemical hazard identification and for classification and labelling. Current methods employ death as an endpoint (Organisation for Economic Co-operation and Development (OECD) test guideline (TG) 403 and TG436) while the recently approved fixed concentration procedure (FCP) (OECD TG433) uses fewer animals and replaces lethality as an endpoint with evident toxicity. Evident toxicity is the presence of clinical signs that predict that exposure to the next highest concentration will cause severe toxicity or death in most animals. Approval of TG433 was the result of an international initiative, led by the National Centre for the Replacement, Refinement & Reduction of Animals in Research (NC3Rs), which collected data from six laboratories on clinical signs recorded for inhalation studies on 172 substances. This paper summarises previously published data and describes the additional analyses of the dataset that were essential for approval of the TG.

Acute inhalation studies are conducted in animals as part of chemical hazard identification and characterisation, including for classification and labelling purposes. Current accepted methods use death as an endpoint (OECD TG403 and TG436), whereas the fixed concentration procedure (FCP) (draft OECD TG433) uses fewer animals and replaces lethality as an endpoint with ‘evident toxicity.’ Evident toxicity is defined as clear signs of toxicity that predict exposure to the next highest concentration will cause severe toxicity or death in most animals. A global initiative including 20 organisations, led by the National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs) has shared data on the clinical signs recorded during acute inhalation studies for 172 substances (primarily dusts or mists) with the aim of making evident toxicity more objective and transferable between laboratories. Pairs of studies (5 male or 5 female rats) with at least a two-fold change in concentration were analysed to determine if there are any signs at the lower dose that could have predicted severe toxicity or death at the higher concentration. The results show that signs such as body weight loss (>10% pre-dosing weight), irregular respiration, tremors and hypoactivity, seen at least once in at least one animal after the day of dosing are highly predictive (positive predictive value > 90%) of severe toxicity or death at the next highest concentration. The working group has used these data to propose changes to TG433 that incorporate a clear indication of the clinical signs that define evident toxicity.

Silibinin, a flavonolignan from milk thistle, has intestinal cancer chemopreventive efficacy in rodents. It is a strong antioxidant and modulates the insulin-like growth factor (IGF) system by increasing circulating levels of IGF-binding protein 3 (IGFBP-3) and decreasing levels of IGF-I. Here, the hypothesis was tested that administration of oral silibinin generates agent levels in human blood and colorectal and hepatic tissues consistent with pharmacologic activity. Patients with confirmed colorectal adenocarcinoma received silibinin formulated with phosphatidylcholine (silipide) at dosages of 360, 720, or 1,440 mg silibinin daily for 7 days. Blood and biopsy samples of normal and malignant colorectum or liver were obtained before dosing, and blood and colorectal or hepatic tissues were collected at resection surgery after the final silipide dose. Levels of silibinin were quantified by high-pressure liquid chromatography-UV, and plasma metabolites were identified by liquid chromatography-mass spectrometry. Blood levels of IGFBP-3, IGF-I, and the oxidative DNA damage pyrimidopurinone adduct of deoxyguanosine (M1dG) were determined. Repeated administration of silipide was safe and achieved levels of silibinin of 0.3 to 4 μmol/L in the plasma, 0.3 to 2.5 nmol/g tissue in the liver, and 20 to 141 nmol/g tissue in colorectal tissue. Silibinin monoglucuronide, silibinin diglucuronide, silibinin monosulfate, and silibinin glucuronide sulfate were identified in the plasma. Intervention with silipide did not affect circulating levels of IGFBP-3, IGF-I, or M1dG. The high silibinin levels achieved in the human colorectal mucosa after consumption of safe silibinin doses support its further exploration as a potential human colorectal cancer chemopreventive agent.

Naturally occurring anthocyanins possess colorectal cancer chemopreventive properties in rodent models. We investigated whether mirtocyan, an anthocyanin-rich standardized bilberry extract, causes pharmacodynamic changes consistent with chemopreventive efficacy and generates measurable levels of anthocyanins in blood, urine, and target tissue. Twenty-five colorectal cancer patients scheduled to undergo resection of primary tumor or liver metastases received mirtocyan 1.4, 2.8, or 5.6 grams (containing 0.5-2.0 grams anthocyanins) daily for 7 days before surgery. Bilberry anthocyanins were analyzed by high performance liquid chromatography (HPLC) with visible or mass spectrometric detection. Proliferation was determined by immunohistochemistry of Ki-67 in colorectal tumor. Concentrations of insulin-like growth factor (IGF)-I were measured in plasma. Mirtocyan anthocyanins and methyl and glucuronide metabolites were identified in plasma, colorectal tissue, and urine, but not in liver. Anthocyanin concentrations in plasma and urine were roughly dose-dependent, reaching ∼179 ng/gram in tumor tissue at the highest dose. In tumor tissue from all patients on mirtocyan, proliferation was decreased by 7% compared with preintervention values. The low dose caused a small but nonsignificant reduction in circulating IGF-I concentrations. In conclusion, repeated administration of bilberry anthocyanins exerts pharmacodynamic effects and generates concentrations of anthocyanins in humans resembling those seen in ApcMin mice, a model of FAP adenomas sensitive to the chemopreventive properties of anthocyanins. Studies of doses containing