ABSTRACT
Background: Groundwater nitrate pollution is an important environmental problem in water resources management. In this regard, specific measures aiming at prevention of water pollution will be helpful to managers and decision-makers. Identification of aquifers' vulnerable areas and determination of groundwater protection zones using most widely used models, such as DRASTIC and CD, are one of the most useful approaches in water resources' hygiene
Objective: The present study aimed to assess the vulnerability of Shiraz plain's unconfined aquifer using the above-mentioned models
Methods: The main hydro-geologic factors affecting the transmission of pollution, including depth to water table, net recharge, aquifer media, soil media, topography, impact of the vadose zone, aquifer hydraulic conductivity, and land use parameters were rated, weighted, and integrated using GIS 9.3. Finally, the maps of Shiraz plain's unconfined aquifer vulnerability were prepared
Results: The vulnerability maps based on these two indexes showed very similar results, identifying the southeastern part of the aquifer, around Maharlu Lake, as the vulnerable zone. The observed nitrate concentrations from the wells in the underlying aquifer were in accordance with these findings. The results of sensitivity analyses indicated the depth parameter as the most effective parameter in vulnerability assessment of Shiraz plain
Conclusion: As Shiraz plain has been covered with fine-grained sediments, except for some central and south-east regions which have moderate vulnerability and high nitrate concentration, its vulnerability is low. Given the intensive agricultural activities and also the rise in groundwater level in southeastern regions, more attention should be paid to these areas
ABSTRACT
Background: Evidence shows that job stress potentially has adverse effect on individuals' health and organizational productivity. It has, therefore, become an important issue in the occupational health context. The aims of this study were to investigate job stress dimensions among nurses of Shiraz University of Medical Sciences [SUMS] hospitals and comparing the results with the findings of the previous studies conducted in other countries
Methods: In this cross-sectional study, 385 randomly selected nurses of SUMS participated. The Persian version of Job Content Questionnaire [P-JCQ] and demographic questionnaire were used for data collection. The linguistic validity and psychometric properties of P-JCQ have been assessed and approved in a previous study. One sample t-test was used to examine the differences between means of job stress dimension scores of the present and those of the previous studies carried out in other countries
Results: The means [SD] of decision latitude, psychological job demands, social support, physical job demands and job insecurity were found to be 58.15 [6.50], 38.19 [5.14], 22.67 [3.67], 16.03 [2.58], and 7.74 [3.85], respectively. The results revealed that decision latitude and social support dimensions were in a low level among the study subjects. In contrast, psychological job demand, physical job demand, and job insecurity dimensions were shown to be in a high level
Conclusion: The SUMS hospital environment collectively imposes higher job stress on the nurses as compared to that of other countries. To prevent harmful effects of job stress on the nurses' health and job performance, developing macro-ergonomic strategies in this working environment, such as enhancing job control, reducing job demands, and providing supportive climate, seem necessary
ABSTRACT
Background: Noise is one of the most pervasive hazards in industrial settings. This retrospective study was carried out to assess the effects of noise exposure on hearing status, blood lipids and blood pressure of employees of a local fireclay mine
Methods: Two hundred and forty male workers were studied. Data on audiometric measurements, blood lipids and blood pressure were derived from the workers' medical records and analyzed. Furthermore, area noise measurements were performed. Data were analyzed using SPSS version 16.0
Results: Workers were exposed to a mean noise level of 91 +/- 15 dB. The means of triglyceride [TG], total cholesterol [TC], systolic and diastolic blood pressure [SBP and DBP] were within the normal range for the first three years of the study. However, a slight, non-significant increase in TG level was noted in 2010. Most of the participants [63.6%] suffered from moderate hearing loss [HL]. About 23.6% and 12.7% of the employees had developed severe and mild HL, respectively. A statistically significant difference was noted in the number of workers with high-frequency noise-induced HL. Furthermore, a statistically significant association was found between the mean of highfrequency HL and log-transformed TG values in 2009 and 2010
Conclusions: High frequency HL could be used as a biomarker for identifying workers exposed to excessive noise levels. Highfrequency HL developed over a 4-year exposure to noise was associated with hypertriglyceridemia. Implementing a hearing conservation program seems to be mandatory to prevent further increases in the number of workers who are already in the severe HL group