Journal of School of Public Health and

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  Background and Aim : Contamination of the surface soils of the urban ecosystem with heavy metals poses potential ecological risks. In this research, a preliminary investigation was carried out to evaluate the potential ecological risk of cadmium and lead contamination in urban park soils in Assadabed City, Iran.

  Materials and Methods : Soil samples were taken from the urban parks of Asadabad city and analyzed for heavy metals using atomic absorption spectrometry. Based on the concentrations of Cd and Pb in the soils, contamination factor (CF), contamination degree (Cdeg) and potential ecological risks status (RI) of the soils were calculated.

  Results : Preliminary results showed a low degree of contamination of urban parks of of Asadabad City. Assessment of the potential ecological risk index (RI) indicated that the cumulative heavy metal contents of the soil do not pose any significant ecological risks. In any case, further analysis of the data showed that the potential ecological risk posed by cadmium was higher than that by lead.

  Conclusion : The findings indicate that although urban park soils may be polluted due to presence of certain heavy metals, on the whole their ecological risk is insignificant. These findings can help greatly environmental managers in planning, risk assessment and decision-making in the area.

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Background and Aim: Ergonomics climate indicates employee perceptions of the extent to which the organization emphasizes and supports the design and modification of work, so that both performance and well-being of the personnel are improved. The purpose of this study was to determine the validity and reliability of the Persian version of the ergonomics climate assessment questionnaire in order to create a suitable tool for determining the overall values of an organization in connection with ergonomics and climate assessment.
Materials and Methods: First, the ergonomics climate assessment questionnaire was obtained from the Colorado State University of America, where it had been developed. The back-translation method was used to confirm its language suitability and precision. The content validity of the questionnaire was assessed by 10 relevant experts, followed by a cross-sectional study using a sample of 50 employees of a power generation plant using Cronbach's alpha to determine its reliability.
Results: The content validity ratio (CVR), content validity index (CVI) and reliability of thequestionnaire were found to be 0.90, 0.94 and 0.96 (a for the 59 items), respectively. These resultsindicating that the questionnaire is a valid and reliable tool.
Conclusion: Considering the acceptable validity and reliability of the ergonomic climate assessment questionnaire, it can be used as a valid and reliable tool to assess and analyze the status of ergonomic climate in different industries and organizations in Iran.

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Background and Aim: Healthy food and nutrition have always been a serious concern of human beings. In this regard, food safety is extremely important. As an example, nitrates in foods may affect their safety. The purpose of this study was to investigate the nitrate contents of highly consumed food products (potatoes, tomatoes and onions) on sale in wholesale fruit and vegetable markets (Heravi, Mellat and Lavizan) in District 4 of Tehran, Iran.
Materials and Methods: Samples of the foods were collected in winter and spring, and their nitrate content was measured spectrophotometrically. The SPSS-20 software was used for data analysis.
Results: The results showed that there was a statistically significant difference between the vegetables nitrate contents in winter and spring. The nitrate content of onions in the spring in the Heravi market and that of potatoes in the winter in the Lavizan market were higher than the respective standard, while that of tomatoes was less than the standard in both seasons.
Conclusion: The nitrate content in the samples was in most cases below the respective standard, indicating that the vegetables on sale in the wholesale markets in Tehran were acceptable as regards nitrate content (at least in spring and winter).