M Mosaferi, M Shakerkhatibi, A Mehri Badloo,
Volume 8, Issue 4 (20 2011)
Abstract
Background and Aim: Recently the use of heterotrophic plate count (HPC) has received much attention as a supplementary indicator of the MPN test in water quality control. The US Environmental Protection Agency (USEPA) has declared 500 cfu/mL as the maximum acceptable level for heterotrophic bacteria in distribution networks. Currently the HPC determination is not among the routine control items in Tabriz city and there is no published information on the presence of heterotrophic bacteria in that city's potable water. In this study the presence of HPC in potable water main was determined in Tabriz city, Iran.
Materials and Methods: A total of 50 water samples, representing drinking water of the whole city of Tabriz, were taken randomly from different districts of Tabriz city and their HPC, coliform, residual chlorine, turbidity, temperature, and pH were measured. For the heterotrophic bacteria the R2A and Nutrients Agar culture media were used, while the spread plate count method was used for the HPC test. The statistical tests used for data analysis were the t-test and regression.
Results: In 50% of the samples heterotrophic bacteria were present. In 6 districts the HPC was higher than 500 cfu/mL. Based on Nutrient Agar and R2A, the HPC indicator in Tabriz drinking water was 184±340 and 154±315 cfu/mL, respectively, the growth rate being higher in the former medium. There was a significant correlation between the HPC and residual chlorine in both media (for Nutrients Agar, p<0.05 R= -0.347, and for R2A, p<0.05 R= -0.312). Also, there was a significant positive correlation between the HPC and pH (p<0.05). Further analysis of the data showed that the correlation between HPC values in both media was also significant (p<0.95, R= 0.95).
Conclusion: The presence of heterotrophic bacteria in 50% of the water samples tested indicates that drinking water contamination with these bacteria is a public health problem in Tabriz city. As a result, monitoring of HPC at least once every 6 or, at least, 12 months, together with coliform bacteria, and the comparison of the results over time can help to better determine water quality in the distribution system, as well as boost the system operation and ensure drinking water with a high quality.
Ahmad Mehri, Ali Akbar Hasanpour, Akram Robatjazi, Mehrsadat Mahdizadeh,
Volume 19, Issue 2 (9-2021)
Abstract
Background and Aim: Social capital is a social component affecting health outcomes considered to be one of the important factors influencing health inequity in the communities; it is one of the main concerns of health system in the suburbs. This study aimed to determine social capital and its relationships with demographic factors and perceived health status in the suburbs of Mashhad, Iran in 2020.
Materials and Methods: This was a descriptive-analytical study including 300 residents in the suburbs of Mashhad, Iran selected using the cluster sampling method. The data collection tool was a questionnaire containing demographic and perceived health status questions, as well as the Onyx and Bullen social capital questionnaire. Data were analyzed using the t-test, Pearson correlation test, one-way analysis of variance and multiple linear regression, using SPSS-version 24.
Results: The mean age of the individuals was 34.6± 11 years and their social capital score 53.63± 10.52. Among the eight social capital components, the value of life (57.91± 17.7) and participation in the local community (44.28± 15.28) were found to have the highest and lowest mean scores, respectively. Further analysis of the data showed that sex, education level and perceived health could predict 23% of the changes in the total social capital (p <0.001).
Conclusion: In this study, the level of social capital of the participants was low, but the demographic factors and health status were related to social capital. Therefore, policymakers and social and health planners should design and implement community-based interventions to improve the level of social capital.
