long-term exposure to high concentrations of fluoride is associated with several adverse effects on human including dental and skeletal fluorosis. we studied all the groundwater wells located in rural areas of khaf city, razavi province, northeastern iran between 2009 and 2010. fluoride concentration of water samples was measured by spadns method. we found that in rural areas the fluoride conce...

proposing a noise standards should be considered seriously by the governmental authorities because of the prevalence of hazardous noise exposure and the seriousness of the effects . in a survey founded by world health organization’s regional office in iran, the existing as well as gathered data from field were applied to propose a national occupational noise exposure limit. the collected data p...

This paper describes cognitive characteristics of timing difference for closed captions superimposed onto TV news programs. It was reported that timing delays for superimposing disrupts hearing impaired people's enjoyment and intelligibility of TV, but nobody has yet investigated the permissible limit for timing difference. This study presents subjects' permissible and preferable limits of the ...

Introduction: In recent years, attraction toward drinking bottled mineral water has increased. Therefore, chemical composition and safety of these waters considering trace elements and heavy metals should confirm the national or international standard limits. The aim of this study was to evaluate and comparison of the mineral and heavy metal composition of bottled waters in Bandar Abbas with Ir...

conclusions the adoption of 85 dba as the permissible exposure limit has preserved hearing threshold level among participants at 3000 hz compared to those who embraced 90 dba. patients and methods this is an intervention study done on two automobile factories. there were 203 employees exposed to noise levels beyond the action level. hearing protection devices were distributed to reduce noise le...

aim: this study was conducted to investigate the accumulation of three heavy metals including lead, tin and zinc in the liver and muscle tissues of 60 silver carp (hypophthalmichthys molitrix) collected from different stations of the anzali wetland (located at the west south of caspian sea): pirbazar, anzali, khazarvila, beshman, sangachin and abkenar, in april 2011. materials and methods: samp...

The purpose of this study is investigating the chemical analysis of drinking water in Kashan district. This district contained Kashan, Aran and Bidgol and Nooshabad cities and it had an estimated population more than of 400,000 in 2007. 42 Samples were collected during October 2006 to May 2007.The temperature of the water Samples is in the range 25-30°C. The water samples were analyzed for pH ,...