A comparison of health indicators and social determinants of health between Israel and the Occupied Palestinian Territories.

Despite the proximity and interconnections between Israel and the Occupied Palestinian Territories (oPt), great disparities persist in health status between these two regions. This disparity is seen in infant, child and maternal mortality, life expectancy, mortality rates for leading causes of death and measures of mental well-being. This paper compares health indicators between oPt and Israel and examines the social determinants of health that may be responsible for differences between them. Data on health indicators were obtained from publicly available publications or websites of the World Health Organization and The World Bank, as well as the database of the Global Burden of Disease Project of the Institute of Health Metrics and Evaluation. Data on the social determinants of health were obtained from publications and websites of the United Nations, the World Bank, the U.S. Central Intelligence Agency, Palestinian and Israeli government reports, reports from non-governmental organisations, peer-reviewed studies and news articles. The health disparities are due to a complex mix of factors involving economic conditions, food insecurity, environmental exposures, psychological trauma and stress, and access to health services, most of which can be related directly or indirectly to the Israeli military occupation of oPt.

Toenail Manganese: A Sensitive and Specific Biomarker of Exposure to Manganese in Career Welders.

Manganese (Mn) is an essential trace metal. It is also a component of welding fume. Chronic inhalation of manganese from welding fume has been associated with decreased neurological function. Currently, there is not a universally recognized biomarker for Mn exposure; however, hair and toenails have shown promise. In a cohort of 45 male welders and 35 age-matched factory control subjects, we assessed the sensitivity and specificity of toenail Mn to distinguish occupationally exposed subjects from unexposed controls. Further we examined the exposure time window that best correlates with the proposed biomarker, and investigated if non-occupational exposure factors impacted toenail Mn concentrations. Toenail clippings were analyzed for Mn using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Exposure to respirable Mn-containing particles (<4 µm) was estimated using an exposure model that combines personal air monitoring, work history information, and dietary intake to estimate an individual's exposure to Mn from inhalation of welding fume. We assessed the group differences in toenail concentrations using a Student's t-test between welders and control subjects and performed a receiver operating characteristic (ROC) curve analysis to identify a threshold in toenail concentration that has the highest sensitivity and specificity in distinguishing welders from control subjects. Additionally, we performed mixed-model regressions to investigate the association between different exposure windows and toenail Mn concentrations. We observed that toenail Mn concentrations were significantly elevated among welders compared to control subjects (6.87 ± 2.56 versus 2.70 ± 1.70 µg g-1; P < 0.001). Our results show that using a toenail Mn concentration of 4.14 µg g-1 as cutoff allows for discriminating between controls and welders with 91% specificity and 94% sensitivity [area under curve (AUC) = 0.98]. Additionally, we found that a threshold of 4.66 µg g-1 toenail Mn concentration enables a 90% sensitive and 90% specific discrimination (AUC = 0.96) between subjects with average exposure above or below the American Conference of Governmental Industrial Hygienist (ACGIH) Threshold Limit Value (TLV) of 0.02 mg m-3 during the exposure window of 7-12 months prior to the nail being clipped. Investigating which exposure window was best reflected by toenail Mn reproduced the result from another study of toenail Mn being significantly (P < 0.001) associated with exposure 7-12 months prior to the nail being clipped. Lastly, we found that dietary intake, body mass index, age, smoking status, and ethnicity had no significant effect on toenail Mn concentrations. Our results suggest that toenail Mn is a sensitive, specific, and easy-to-acquire biomarker of Mn exposure, which is feasible to be used in an industrial welder population.

Association of ozone and particulate air pollution with out-of-hospital cardiac arrest in Helsinki, Finland: evidence for two different etiologies.

Out-of-hospital cardiac arrest (OHCA) has been previously associated with exposure to particulate air pollution. However, there is uncertainty about the agents and mechanisms that are involved. We aimed to determine the association of gases and particulates with OHCA, and differences in pollutant effects on OHCAs due to acute myocardial infarction (AMI) vs those due to other causes. Helsinki Emergency Medical Services provided data on OHCAs of cardiac origin (OHCA_Cardiac). Hospital and autopsy reports determined whether OHCAs were due to AMI (OHCA_MI) or other cardiac causes (OHCA_Other). Pollutant data was obtained from central ambient monitors. A case-crossover analysis determined odds ratios (ORs) for hourly lagged exposures (Lag 0-3) and daily lagged exposures (Lag 0d-3d), expressed per interquartile range of pollutant level. For OHCA_Cardiac, elevated ORs were found for PM(2.5) (Lag 0, 1.07; 95% confidence interval (CI): 1.01-1.13) and ozone (O(3)) (Lag 2d, 1.18; CI: 1.03-1.35). For OHCA_MI, elevated ORs were found for PM(2.5) (Lag 0, 1.14; CI: 1.03-1.27; Lag 0d, 1.17; CI: 1.03-1.33), accumulation mode particulate (Acc) (Lag 0d, 1.19; CI: 1.04-1.35), NO (Lag 0d, 1.07; CI: 1.01-1.13), and ultrafine particulate (Lag 0d, 1.27; CI: 1.05-1.54). For OHCA_Other, elevated ORs were found only for O(3) (Lag 1d, 1.26; CI: 1.07-1.48; Lag 2d, 1.30; CI: 1.11-1.53). Results from two-pollutant models, with one of the pollutants either PM(2.5) or O(3), suggested that associations were primarily due to effects of PM(2.5) and O(3), rather than other pollutants. The results suggest that air pollution triggers OHCA via two distinct modes: one associated with particulates leading to AMI and one associated with O(3) involving etiologies other than AMI, for example, arrhythmias or respiratory insufficiency.

Ergonomics. The effect of occupational exposure to environmental tobacco smoke on the heart rate variability of bar and restaurant workers.

Changes in heart rate variability (HRV) have been linked with cardiac disease and death. Exposure to particulate matter from various sources such as tobacco smoke has been shown to cause alterations in HRV. This study investigated the effects of occupational exposure to environmental tobacco smoke (ETS) on HRV. Air monitoring was conducted in three bars in which smoking was permitted and one bar where smoking was not permitted. Pre- and post-work shift heart rate monitoring was conducted on volunteer staff from the establishments. Heart rate variability parameters, including SDNN and RMSSD, were calculated, and the differences between pre- and post-shift values were plotted and analyzed with respect to ETS exposure. Post-shift minus pre-shift values of SDNN and RMSSD significantly decreased with exposure to ETS (p < 0.05). Occupational exposure to ETS may decrease heart rate variability.

Manganese exposure among smelting workers: relationship between blood manganese-iron ratio and early onset neurobehavioral alterations.

A biomarker for detection of early onset neurobehavioral alterations in manganism remains unknown. The purpose of this study was to use a neurobehavioral test battery to identify subtle changes in Mn-induced motor and memory dysfunction and to relate the quantifiable neurological dysfunction to an established Mn-exposure index such as blood manganese-iron ratio (MIR). A total of 323 subjects were recruited to control (n=106), low-exposure (122), and high-exposure (95) groups. The test battery consisted of standard testing procedures including the nine-hole and groove-type steadiness tester, Benton visual retention test, and Purdue pegboard coordination test. No significant health problems or clinically diagnosed neurological dysfunctions were observed. Benton test did not reveal any abnormal memory deficits among Mn-exposed smelters, nor did the groove and nine-hole tests detect any abnormality in dynamic and static steadiness in tested subjects. Purdue pegboard test showed a remarkable age-related decline in fine movement coordination among all study participants regardless of the Mn-exposure condition. Mn exposure significantly exacerbated this age-related deterioration. Statistical modeling revealed that the plasma and erythrocyte MIR (i.e., pMIR and eMIR, respectively) were associated with Purdue pegboard scores. Among all subjects whose MIR were above the cut-off value (COV), pMIR was significantly correlated with pegboard scores (r=-0.261, p=0.002), whereas for those subjects over the age of 40, the eMIR, but not pMIR, was associated with declined pegboard performance (r=-0.219, p=0.069). When both factors were taken into account (i.e., age>40 and MIR>the COV), only pMIR was inversely associated with pegboard scores. Combining their usefulness in Mn-exposure assessment, we recommend that the blood Mn-Fe ratio may serve as a reasonable biomarker not only for assessment of Mn exposure but also for health risk assessment.

Manganese exposure among smelting workers: blood manganese-iron ratio as a novel tool for manganese exposure assessment.

Unexposed control subjects (n = 106), power distributing and office workers (n = 122), and manganese (Mn)-exposed ferroalloy smelter workers (n = 95) were recruited to the control, low and high groups, respectively. Mn concentrations in saliva, plasma, erythrocytes, urine and hair were significantly higher in both exposure groups than in the controls. The Fe concentration in plasma and erythrocytes, however, was significantly lower in Mn-exposed workers than in controls. The airborne Mn levels were significantly associated with Mn/Fe ratio (MIR) of erythrocytes (eMIR) (r = 0.77, p < 0.01) and plasma (pMIR) (r = 0.70, p < 0.01). The results suggest that the MIR may serve as a useful biomarker to distinguish Mn-exposed workers from the unexposed, control population.

Out-of-hospital cardiac arrest and airborne fine particulate matter: a case-crossover analysis of emergency medical services data in Indianapolis, Indiana.

BACKGROUND: Previous studies have found particulate matter (PM) < 2.5 microm in aerodynamic diameter (PM2.5) associated with heart disease mortality. Although rapid effects of PM2.5 exposure on the cardiovascular system have been proposed, few studies have investigated the effect of short-term exposures on out-of-hospital cardiac arrest (OHCA). OBJECTIVES: We aimed to determine whether short-term PM2.5 exposures increased the risk of OHCA and whether risk depended on subject characteristics or presenting heart rhythm. METHODS: A case-crossover analysis determined hazard ratios (HRs) for OHCAs logged by emergency medical systems (EMS) versus hourly and daily PM2.5 exposures at the time of the OHCA and for daily and hourly periods before it. RESULTS: For all OHCAs (n = 1,374), exposures on the day of the arrest or 1-3 days before arrest had no significant effect on the incidence of OHCA. For cardiac arrests witnessed by bystanders (n = 511), OHCA risk significantly increased with PM2.5 exposure during the hour of the arrest (HR for a 10-microg/m3 increase in PM2.5 exposure = 1.12; 95% confidence interval, 1.01-1.25). For the subsets of subjects who were white, 60-75 years of age, or presented with asystole, OHCA risk significantly increased with PM2.5 during the hour of the arrest (HRs for a 10-microg/m3 increase in PM2.5 = 1.18, 1.25, or 1.22, respectively; p < 0.05). HR generally decreased as the time lag between PM2.5 exposure and OHCA increased. CONCLUSION: The results suggest an acute effect of short-term PM2.5 exposure in precipitating OHCAs, and a need to investigate further the role of subject factors in the effects of PM on the risk of OHCA.

Aerosol probes of emphysema progression in dogs treated with all trans retinoic acid--an exploratory study.

This study used aerosol probes and lung function tests to investigate whether all trans retinoic acid (RA) can reverse experimental emphysema in dogs. Three dogs were evaluated with lung mechanics tests, including inspiratory capacity (IC), total lung capacity (TLC), and the ratio of forced expired volume in 0.5 sec to forced vital capacity (FEV0.5/FVC), an aerosol-derived measure of pulmonary airspace size (effective airspace diameter, EAD), and an aerosol-derived measure of nonuniform ventilation (aerosol dispersion, AD). Emphysema was induced by exposure to aerosolized papain. At 11 or 12 weeks post-papain exposure, dogs received oral RA (2 mg/kg/day) for 8 weeks, and were followed for an additional 4 weeks after stopping RA treatment. In all dogs, lung injury increased in the first 11-12 weeks following papain exposure, as evidenced by increasing trends of inspiratory capacity IC, TLC, EAD, and AD, and a decreasing trend of FEV0.5/FVC. These parameters of lung injury partially and transiently reversed their trends between 2 and 6 weeks following the initiation of RA treatment. A sham RA-treated group was not studied. However, similar reversals of lung injury were not seen in a previous study of dogs treated with papain but not RA, suggesting that RA altered emphysema progression in the current study. The limited reversal of lung injury in this study contrasts with more pronounced treatment effects seen in previous studies with rats. This paper discusses possible reasons for differences in these studies, as well as suggestions for improved experimental investigations of emphysema therapies.

Therapeutic effects of alpha-lipoic acid on bleomycin-induced pulmonary fibrosis in rats.

Pulmonary fibrosis (PF) is a major side effect of radiotherapy and chemotherapy. Recent clinical trials, unfortunately, have failed to identify any therapeutic agent which has the potential to reduce the consequences of this devastating condition. Reactive oxygen species and tissue remodeling regulators, such as metalloproteinases (MMPs) and their inhibitors (TIMPs), are thought to be involved in the development of PF. We investigated these factors to determine the protective effects of antioxidant alpha-lipoic acid (LA) against antineoplastic agent bleomycin (BLM)-induced oxidant lung toxicity in Sprague-Dawley rats. At different time intervals after BLM administration, pathological changes of the lung were analyzed with the measurement of total protein in bronchoalveolar lavage fluid (BALF), hydroxyproline (HYP) content and the level of three oxidative stress markers, i.e. malondialdehyde (MDA), the GSH/GSSG ratio, and total antioxidative capability (T-AOC). Also, the expression changes of MMP-1 and TIMP-1 were measured. At day 14 or 28 after BLM administration, protein content in BALF, and HYP, MDA and T-AOC contents of the lung increased significantly with a decreased GSH/GSSG ratio, implicating an increased efflux of GSSG from the lung and consumption of GSH. In contrast, treatment with LA protected BLM-induced pulmonary injury by suppressing oxidative stress with the reduction of MDA, and the enhancement of the GSH/GSSG ratio and T-AOC. The BLM-stimulated symptoms of PF were relieved with significant reduction of HYP and total proteins in LA-treated rats. LA also ameliorated the MMP-1/TIMP-1 ratio. These results suggest that LA inhibits BLM-induced lung toxicity associated with oxidative damage. Therefore, antioxidant LA has a potential therapeutic effect in the prevention and alleviation of PF.

A comparison of total, respirable, and real-time airborne particulate sampling in horse barns.

Measurements of total, respirable, and real-time airborne particulate were obtained in 12 horse barns in summer and winter. Respirable and total particulate concentrations were measured gravimetrically; real-time particulate was measured with an aerosol photometer. Total particulate (TP) ranged from nondetectable (ND) to 2.1 mg/m3 and from ND to 1.2 mg/m3 for winter and summer sampling, respectively. Respirable particulate (RP) ranged from ND to 0.2 mg/m3 and from ND to 0.7 mg/m3 for winter and summer measurements, respectively. The mean respirable fraction of particulate for summer and winter measurements was 0.63 and 0.34, respectively Real-time particulate (RTP) concentration was significantly correlated with TP for winter measurements and for pooled data but was not significantly correlated with RP for winter, summer, or pooled measurements. Peak, 10-sec average levels of RTP were estimated to range up to 22 mg/m3 in the samples collected. The data suggest that (a) airborne particulate concentrations and particle size distributions vary considerably among horse barns, and (b) real-time sampling, with an aerosol photometer, may be a more reliable measure of airborne TP than airborne RP in these environments.

Heart rate variability and particulate exposure in vehicle maintenance workers: a pilot study.

The association between occupational exposure to PM(2.5) and heart rate variability was investigated in a repeated measures, longitudinal study of vehicle maintenance workers occupationally exposed to automobile emissions. Five subjects were monitored for occupational exposure to fine particulate matter (PM(2.5)) on 6 workdays using an aerosol photometer, validated with side-by-side sampling with a gravimetric method. End-of-day heart rate variability statistics were derived using short-term electrocardiogram recordings for each participant. Workplace carbon monoxide and outdoor, ambient fine particulate matter were also monitored. Regression statistics were used to investigate associations between same-day PM(2.5) levels and heart rate variability statistics using mixed-effects multiple regression of pooled data. No statistically significant associations were observed between occupational PM(2.5) and measures of heart rate variability. A statistically significant increase in total spectral power was associated with ambient PM(2.5) (p < 0.05). The data suggest a threshold below which no degradation in cardiac autonomic control of healthy workers occurs when challenged by occupational PM(2.5) exposure. This study was limited in population, exposure level, and type of particulate exposures. Additional studies are recommended on broader occupational populations.

Determination of the attenuation properties of laboratory gloves exposed to an ultraviolet transilluminator.

The transmission of ultraviolet radiation (UVR) from an ultraviolet transilluminator through three types of laboratory gloves (latex, nitrile, vinyl) was determined using two independent methods. First, transmittance was measured with a radiometer equipped with UVA and actinic UV detectors. Second, a spectrophotometer was used to determine the UVR transmittance vs. wavelength (250-440 nm); this data was then used to compute the effective attenuation of the glove material. The average UVA percent transmittance using the radiometer method with an unstretched glove was 73.4%, 0.18%, and 1.10% for vinyl, nitrile, and latex, respectively. The average actinic percent transmittance for an unstretched glove was 13.3%, 0.015%, and 0.024% for vinyl, nitrile, and latex, respectively. Slight increases in UVR transmittance resulted from stretching the gloves by 30% or wetting them with saline. Six hours of UVR exposure decreased transmittance of vinyl gloves and increased transmittance by latex gloves. Results from the spectrophotometer method and radiometer methods of determining UVR transmittance agreed that vinyl gloves had the highest transmittance; however, the spectrophotometer method greatly overestimated UV glove attenuation due to the effect of light scattering by the glove material. The study suggests that in some circumstances, vinyl gloves will provide inadequate protection against workplace ultraviolet radiation.