Cognitive functions changes in Egyptian sewage networks workers

Hydrogen sulfide is a toxic gas about which much has been written. It constitutes one of the most serious chemical hazards to which sewage network workers are exposed to. The current work aimed at assessment of cognitive dysfunctions among workers of sewer networks and the relation of these changes, if any, to the level of exposure to the biomarker, urinary thiosulfate. A trial for setting a screening test for cognitive function change. The work was conducted among 34 male workers involved in the maintenance of the sewage network and a matched unexposed control group [n = 21]. The participants were subjected to clinical neurological examination, estimation of urinary thiosulfate as hydrogen sulfide exposure biomarker, and assessment of cognitive functions changes by using neurophysiological [simple reaction time, P300 test] and neuropsychological tests [Wechsler Memory Scale] and frontal executive functions. Clinical neurological history revealed significantly higher neurological symptoms [headache, memory defects, lack of concentration] among exposed workers compared to their controls [P < 0.05]. Marked elevation of urinary thiosulfate was observed among the exposed workers [P < 0.001] although this elevation was not correlated with the duration of exposure. Exposed workers showed poor performance of most of neuropsychological tests compared to control subjects. Significantly prolonged simple reaction time and delayed P300 latency were found among sewer network workers. Most of exposed workers had significantly lower Mini-Mental State Examination [MMSE] scoring than that of the controls [P < 0.001]. MMSE was significantly correlated with other neuropsychological tests. Exposure of sewer network workers is associated with significant cognitive dysfunction which can be screened by applying MMSE annually as a screening test of the exposed workers

Impact of long term occupational exposure to ozone emitted from photocopiers on the respiratory system

The objective of this study was to determine the concentration of ozone in the indoor environment in photocopying centers and to investigate its possible respiratory effects among subjects engaged in the work in the photocopying process. Multiple air samples were collected from 4 photocopying centers and a control area containing no photocopying machines. Additionally, a questionnaire of respiratory symptoms was filled in [cough, phlegm, chest tightness and shortness of breath] and pulmonary function tests namely FVC% FEV1/FVC% and FEF25-75% were performed among 27 exposed subjects [15 females and 12 males] who were working in these photocopying centers and 29 matched control subjects [15 females and 14 males]. The measured ozone concentration exceeded the levels recommended by OSHA and NIOSH [200mg/m[3]] i.e 0. 1ppm in almost all air samples taken from the 4 photocopying centers. On the other hand, respiratory symptoms were statistically significantly more prevalent in the exposed group than in the controls. Similar results were obtained regarding the pulmonary function tests. On comparing the exposed subjects with >/= 5 years duration of work with those of < 5 years duration, there was a significant statistical difference [P<0.05] between the mean +/- SD of pulmonary function tests in both groups but no significant difference as regards the respiratory symptoms [P>0.05]. Comparison between the exposed females and males showed no statistical difference of significance. Correlation between the decline in pulmonary functions with duration of work and theTWA/8 hs of ozone was significant. Although, the ozone emitted from the photocopiers usually decays back to oxygen, it may exceed the recommended levels under certain conditions such as poor ventilation and bad maintenance. Long term occupational exposure to excessive amounts of ozone carries the risk of respiratory adverse effects with decline of pulmonary functions. Recommendations were stated to prevent the excessive ozone accumulation in the photocopying centers

1-Hydroxypyrene and interleukin-8 for biological monitoring of vehicle exhaust exposure and effects among gas-station workers

Air pollution encountered in many towns and cities throughout the world is associated with high levels of fuel vapors and motor vehicle-generated exhaust. A consistent association was reported between the levels of particulate matter and semi-volatile organic compounds in the ambient air with increasing mortality and morbidity. Although the epidemiological evidence is strong, there are yet neither established biological mechanisms to explain the toxicity in humans nor biologically established biomarkers for both exposure and severity of disease. This study was done to determine the impact of vehicle exhaust on the human airways among extensively exposed workers in few gas stations. The extent of exposure to polycyclic aromatic hydrocarbons [PAHs] is measured by estimating the level of 1-hydroxypyrene [1-OHP], a pyrene metabolite. Respiratory inflammation is clinically assessed and evaluated using pulmonary function tests. The impact of respired vehicle exhaust on the immunobiology of the respiratory system is evaluated by estimating the level of the cytokine interleukin-8 [IL-8] in serum, being used as an indication for respiratory inflammation and tissue damage. The study population consisted of 34 highway gas-station workers exposed to vehicle exhaust and 30 matched non-exposed office workers. The exposed population was further subdivided into a fueling group [n=22] working in petrol filling of cars and a car washing group [n=12] working in car cleaning. The study population was subjected to thorough clinical examination, pulmonary function testing and laboratory investigations. Measurement of the urinary 1-OHP level was done using the high performance liquid chromatography [HPLC] with electrochemical water detectors. As for the cytokine IL-8, estimation was done using quantitative sandwich enzyme-linked immunosorbent assay [ELISA]. Medical history and clinical examination revealed significantly higher frequency of repeated chest infections among the exposed group [41%] than among the control subjects [6.6%]. As for chronic bronchitis, asthmatic attacks and dyspnea, the results were higher among the exposed groups but with no statistically significant difference. Ventilation function tests revealed the presence of an obstructive affection among exposed workers correlating strongly with age and smoking habits but not with the duration of exposure. The level of FEV[1] /FVC ratio correlated with the level of 1-OHP that is the PAHs biomarker of exposure [r=-0.313; P<0.01]. The urinary 1-OHP was found to be significantly higher among the exposed population, but still no significant correlation was obtained with exposure duration. The serum IL-8 level was markedly elevated among the exposed workers and significantly correlated with FEF[25%-75%] [r = -0.263; P<0.05] revealing the presence of a high risk of chronic inflammation and lung cancer. Occupational exposure of workers in the gas stations to vehicle exhaust carries an increased risk for respiratory diseases such as repeated chest infections, chronic bronchitis and asthmatic attacks as proved by the presence of dyspnea and the decrement in pulmonary functions. Alteration of the immunological responses of the respiratory epithelium should be considered bearing a risk factor for lung cancer development later on in life. Using the urinary 1-OHP level as a biomarker for exposure and the serum IL-8 level for chronic inflammation and respiratory disease severity and progression should be further evaluated. Long-term impact on the environment needs to be properly investigated in addition to the implementation of protective measures aiming at reducing the occupational exposure to diesel-related polycyclic aromatic hydrocarbons

Effect of work- related stress on secondary school teachers

This work aimed at investigating the effect of job stress on the level of some stress hormones as well as on the blood pressure and heart rate among a group of secondary school female teachers. The study population was composed of 42 secondary school female teachers who were divided into a group of high tasks [n=30] and a group of low task [n=12]. The control group was composed of 43 matched females. Every subject was examined using a medical questionnaire, measurement of radial pulse and blood pressure in addition to measurement of serum cortisol and urinary level of vallinylmandelic acid [VMA], the main catecholamine metabolite. There was a statistically insignificant increase in the prevalence of stress related symptoms such as fatigue, low back pain and gastrointestinal disturbances among the teachers' group compared to the controls. The mean levels of heart rate, systolic blood pressure, diastolic blood pressure, serum cortisol and urinary vallinylmandelic acid were significantly higher among the teachers of the high task group. Heart rate and blood pressure were significantly correlated with the age and duration of work. Being one of the stressful jobs, teaching is associated with an increase of the level of stress hormones [cortisol and catecholamines] with a consequent increase in the blood pressure and the risk of development of heart disease

Oxidative stress among nuclear medicine workers

Whereas large doses of radiation produce identifiable effects within a relatively short period of time, the effects are difficult to ascertain at low doses. The biological effects of low dose radiation have been a focus of research in recent years. This study was conducted an a group of individuals working in a nuclear medicine unit, in an attempt to assess the oxidative stress among them and its relation with the level of exposure reading by dosimetry. This study was carried out among 40 individuals. They were presented in two groups. Exposed group [N = 25] which was subdivided into groups of technicians [N = 7], group of physicians [N = 6] and a group of nurses [N = 12]. Control group included 15 individuals. Estimation of glutathione peroxidase [GPX] plasma level by ELISA technique was used as a marker of oxidative stress. Personal dosimetry readings using TLD [trans luminescent dosimetry] were recorded for every subject in the exposed group. The study revealed marked lowering of glutathione peroxidase level [GPX] with a highly significant difference between the exposed and control subjects [P < 0.01]. The exposure reading by dosimetry was higher among the technicians and physicians groups compared with nurses and the difference was statistically significant [P < 0.05]. Correlation between duration of exposure, dosimetry readings with GPX was negative. Although all dosimetry readings were below the TLV recommended by ICRP. It is evident that there is no threshold for radiation damage below which there is zero risk of deleterious effects

Health profile of workers in the paint industry

In paint manufacture, there is unacceptably high chemical exposure with consequent effects on health. Raw materials used to manufacture paints constitute major chemical hazards to workers as a result of mechanical operations. This study is conducted on a group of workers in a paint industry in an attempt to assess the impact of the paints and coatings on health and on the clinical and laboratory parameters. Due to the high concentration of solvents in this industry, high incidence of renal impairment has been observed. The liver was less affected as evidenced by the serum transaminases level, though these were considered unreliable measures being unrelated to sub-clinical affection. Chest examination revealed the presence of some cases of chronic bronchitis and others with frequent asthmatic attacks. Immunological assessment revealed statistically significant elevation in the serum immunoglobulin E [IgE] among the exposed population. Contrarily, the IgG was not significantly elevated though positively correlating with the IgE level. The paint industry is, therefore, one of the most hazardous industries that need further investigations to keep the levels of toxic dust to minimum and set the precautions to protect the working population