Instrumental neutron activation analysis of air suspended particles in Rasht city, Iran

In addition to gas pollutants, many chemicals and air pollutants are in the form of particulate matter. Particulate matter consists of a complex mixture of variable sized particles and physicochemical composition. These particles mainly contain minerals including Fe, Al, Ca, K, Cu, Ti, Mn, Ni, V and their size, chemical composition and concentration are important to assess the extent to which people has been protected. Instrumental neutron activation analysis [INAA] was employed to determine the composition of elements in material collected on Whatman 41 filter using high volume air sampler in Rasht. Conce ntration of elements including Al, Ca, V, Mg, Cu, Ti, K, Ba, Cl, Mn, Na, As, Br, Cr, La, Sb, Co, Fe, Hg, Sc and Zn were determined in samples. Results showed that the levels of most air pollutants in Rasht to be lower than those measured in other cities in Iran [Tehran, Esfahan and Shiraz] by the same technique. Compared to other cities in world except for some elements, mean concentration of elements in air in Rasht were lower than those reported for Milan, Pavia and Beijing. Although the level of most air pollutants in Rasht are lower than those measured in other cities in Iran, due to considerable differences in element concentrations depending on the day of sample collection, more detailed studies are needed to control the emission of pollutants in this region

Derived intervention levels for mostly consumed foodstuffs in Iran

Measures to protect the public following an accidental release of radionuclides to the environment will depend on the circumstances including the extent of the potential hazards. The projected levels of risk are an important precondition in emergency planning. The levels can be expressed in terms of concentration levels in the environment or in foodstuffs. These derived intervention levels [DILs] can be determined for the range of important radionuclides that could be released to the environment in the event of a nuclear accident. Derived intervention levels for [90]Sr, [131]I, [134]Cs + [137]Cs, [238]Pu + [239]Pu + [241]Am and [103]Ru + [106]Ru radionuclide groups were calculated for infants [<1 year] and adults [>17 years] for mostly consumed foodstuffs in Iran. Calculations of DILs were based on recommendations from international, national organizations and average food consumption rate data for Iran. From our research it was found that DILs for foodstuffs consumed in Iran for above mentioned radionuclide groups except for Ruthenium group are equal to 387, 250, 1023 and 2.8 Bqkg[-1] respectively. The comparison of DILs for foodstuffs consumed in Iran and DILs adopted in the new food and drug administration [FDA] Compliance Policy Guide [CPG] which are 160, 170, 1200, 2 Bq.kg[-1] for [90]Sr, [131]I, [134/137]Cs, [238/239]Pu plus [241]Am radionuclide groups respectively, shows agreement with cesium and plutonium group and higher values for strontium and Iodine group. In the case of nuclear accident or radiological events that might affect our country calculated DILs can be used to prevent or reduce exposure due to consumption of foodstuffs

Transfer of [226]Ra and [137]Cs from tea leaves to drinking tea

Two of the important radionuclides which are entered to environment and human diet are radium-226 [[226]Ra] and cesium-137 [[137]Cs]. It is clear that the methods for preparation of foods such as peeling, washing, cooking or frying can affect the dose which is received by human due the to consumption of foodstuffs. An experiment has been performed at the environmental monitoring section of NRPD, aiming to measure the transfer of [226]Ra and [137]Cs from the tea leaves to drinking part of tea. Tea samples were pulverized to obtain a homogenous matrix which was weighed and placed in 1000 cm[3] Marinelli beaker. After making tea, the liquid tea and tea-discard were analyzed separately. Measurement of [226]Ra and [137]Cs was performed by gamma spectrometry system using a high purity germanium [HPGe] detector with 40 % relative efficiency. The detector was shielded by 10 cm lead an all sides with cadmium -copper as liners. It was found that the activity concentration transferred from tea leaves to drinking tea for [137]Cs and [226]Ra are less than 2% and 17% respectively. On the basis of these measurements it seems that no significant levels of radioactivity of [226]Ra and [137]Cs can be found in drinking part of tea. The low concentration of the mentioned radionuclides in drinking tea is mostly due to tea dust and can be removed by its washing before preparing tea

Estimation of annual effctive dose from 226Ra and due to consumption of foodstuffs by inhabitants of Ramsar 228Ra city, Iran

[226]Ra and [228]Ra contents in foodstuffs of Ramsar which is a coastal city in the northern part of Iran were determined by gamma spectrometry. Measurement results together with food consumption rates were used to estimate annual effective dose from [226]Ra and [228]Ra, due to consumption of food stuffs by inhabitants of Ramsar city. A total of 33 samples from 11 different foodstuffs including root vegetables [beetroot], leafy vegetables [lettuce, parsley and spinach] and tea, meat, chicken, pea, broad bean, rice, and cheese were purchased from markets of Ramsar city and were analyzed for their [226]Ra and [228]Ra concentration. 1-8 kg of fresh weight sample was placed in Marinnelli beaker and sealed. The measurement of natural radioactivity levels as performed by gamma-spectrometry system, using a high purity germanium [HPGe] detector with 40% relative efficiency. The highest concentrations of [226]Ra and [228] Ra were determined in tea samples with 1570 and 1140 mBq/kg, respectively, and the lowest concentration of [226]Ra was in pea, cheese, chicken, broad bean, and beetroot.The maximum estimated annual effective dose from [226]Ra and [226]Ra due to consumption of foodstuffs were determined to be 19.22 and 0.71 microSv from rice and meat samples respectively, where as, the minimum estimated annual effective dose for [226]Ra was 0.017, 0.018 and 0.019 microSv from beetroot, cheese and pea samples respectively

Determination of [226] Ra and [228] Ra concentrations in foodstuffs consumed by inhabitants of Tehran city of Iran

The presence of primordial radionuclide in human habitats has always been a source of prolonged exposure. Measurement of naturally occurring radionuclides in the environment can be used as baseline to evaluate the impact of non-nuclear activities and also routine releases from nuclear installations. A total of 56 samples from 18 different foodstuff including root vegetables [beetroot, carrot, onion, potato, radish and turnip], leafy vegetables[lettuce, parsley, spinach and white cabbage] and lentil, kidney bean, Soya, eggs, rice, meat, tomato and cooking oil were purchased and analyzed by low level gamma spectrometry. The [226] Ra concentrations from root vegetables varied from 13-62 mBqkg[-1] [fw] with turnip of highest concentration, i.e. 62mBq kg[-1]. Among leafy vegetables; parsley showed the maximum concentration of [228] Ra equal to 173 mBqkg[-1] [fw]. [226] Ra and [228] Ra contents in the soya, 394 and 578 mBq kg[-1] [fw] was much higher than those of other samples respectively. Results indicate that foodstuff consumed by Tehran inhabitants have low radium content and are safe, as far as radium concentrations is concerned