Detection of oxidative stress, genotoxicity and changes in plasma fibronectin level induced by aluminium in exposed workers

Concern about the health hazards in the aluminum industry has initiated this study. The aim of this study was to detect fibronectin [FN] and glutathione peroxidase [GPX] levels as well as genotoxicity in aluminium - exposed workers. A group of 40 workers exposed to aluminium in an aluminium reduction plant with a mean duration of exposure of [20.4 +/- 4.8] years and a group of 20 non-exposed workers were subjected to full history taking, thorough clinical examination and ventilatory function measurements. The plasma FN level and the GPX level were estimated in both the exposed workers and the control group. The age and sex distributions among the 2 groups were comparable. Cultured lymphocytes from blood samples were used to perform cytogenetic analysis. A statistically significant reduction in the ventilatory function parameters among the exposed when compared with the control group was demonstrated. The level of plasma FN of the exposed group was significantly higher than that in the control group [p< 0.05]. It was positively correlated with the cytogenetic data of the exposed group [p < 0.05]. The occupational exposure of workers resulted in a statistically significant decrease of [GPX] [p < 0.05] when compared with the control group. Statistically significant difference could also be detected between the exposed and the control groups as regards the CA [gaps and breaks] [p<0.05], while the DNA adducts rates showed no statistically significant difference between both groups. Concerning smoking, the analysis of Spearman correlation showed no significant difference in the results of cytogenetic parameters between smokers and non-smokers in the exposed group, but a significant inverse correlation [p < 0.05] between smoking and GPX level was observed. A nonsignificant correlation could be detected between duration of exposure and both the cytogenetic parameters and each of FN and GPX levels [p > 0.05]. Environmental Al concentrations were also measured at the various workstations and the mean value was [1.5 +/- 0.7] mg/m[3]

Impact of chronic noise exposure on stress response, cardiovascular system and auditory system among marble and granite workers

Noise-induced hearing loss is a major health risk worldwide. Also, noise is one of the commonest physical stressors to which industrial workers are exposed. The objective of this study was to find out whether chronic exposure of workers to loud occupational noise during the daytime would cause changes in their cardiovascular system, stress hormone levels and their hearing thresholds. Thirty eight male marble and granite workers were interviewed, using questionnaires, as regards their medical and occupational history, use of hearing protection and they underwent clinical and laboratory examinations including measurement of blood pressure, ECG and pure-tone audiometry. We assessed noise-induced alterations in physiological stress by measuring serum and urinary levels of cortisol, catecholamines and the lipid profile. In the study areas, the noise levels ranged from 90 to 105 dBA. Results were analyzed and compared with the data of 20 normal persons matched in age, sex and socioeconomic status. Compared to the control group, the exposed workers showed statistically significant noise-induced hearing loss. Noise exposure produced physiological stress responses in workers in the form of significant increase in the serum and urinary cortisol levels after exposure to noise. Also, the exposed group displayed greater serum lipid responses and higher catecholamines levels than their controls. urthermore, blood pressure was significantly higher and ECG changes were more significant among the exposed than the control group. The present data suggest that chronic noise exposure might potentially lead to endocrine dysfunctions. Thus, we can say that workers exposed to loud occupational noise react to the stress and show, in addition to the NIHL, changes in the ECG and development of hypertension which may be attributed to the exposure to noise

Auditory dysfunction among printing workers

The aim of this study is to explore the combined effect of occupational exposure to noise and lead on the hearing process of the exposed workers. Twenty-four exposed workers [48 ears] from two printing facilities at Cairo University and twenty controls [40 ears], not occupationally exposed to noise or lead, were included in this study. All studied personnel were subjected to medical and occupational history, clinical and ENT examination, blood lead level determination and audiological assessment including: pure tone hearing thresholds, otoacoustic emissions [OAE] and auditory brain-stem response [ABR]. The work environments were tested for noise levels which were found to be 88 and 92 dB A, respectively. Statistically significant differences were detected between the exposed group and the controls as regards the hearing thresholds at frequencies 4 and 8 KHz and the OAE, The ABR revealed significant prolongation of the absolute latencies of waves 1 and 3 with increased [1 -3] interpeak latency in the exposed group. The 5/ 1 amplitude ratio was also smaller in the exposed compared to the controls. The blood lead level was significantly higher in the exposed in comparison to the controls [p < 0.001]

Serum melatonin rhythms and prolactin levels in workers exposed to electeomagnetic fields around high voltage electric power lines

One of the more contentious issues in the scientific community today is that of the biological effects of electromagnetic fields [EMFs] and whether or not they adversely affect our health. Many authors studied the effect of EMFs on melatonin and prolactin serum levels. Our results revealed a significant reduction of serum melatonin levels and an increase in prolactin secretion in workers exposed to EMFs around high voltage power lines. A significant correlation was detected between the reduction in serial measurements of melatonin levels and the strength of electric fields, while no such correlation was detected concerning prolactin level. Although negative correlation was found between serial melatonin levels and duration of exposure, yet it was not significant. Previous studies reported that reduction of melatonin increases cell vulnerability to alteration by carcinogenic agents. Concerning prolactin, no such correlation was detected. We recommended periodic screening tests for early detection of cancer in high risk workers