Mercury is a metal found in elemental, organic, and inorganic forms in the nature. This substance is present in the composition of earth crust, soil, air, and even in some tissues of plants and sea animals. Each year nearly 3400 tons of Mercury compounds are released in the environment, which 95% settle in the soil, 3% in the oceans, and 2% in the atmosphere. Different industrial products like medicines, health products (soaps, creams, skin lightening creams), medical instruments (thermometer, sphygmomanometer), some substances in dentistry (amalgam), mirrors, and even some of toys contein Mercury. All of these compounds may enter into the human body via skin, gastrointestinal and respiratory tracts and cause serious harms. They may cause different signs of toxicity, local and general signs and symptoms, and in some cases even they may end up to death. When Mercury toxicity is suspected, in addition to primary evaluations, some special laboratory tests may be of a great help.In order to provide a treatment, the basic steps for all toxicities must be performed to prevent further serious damages,and of course the care giver has to pay attention to specific and non specific features of this toxicity.

Background and Objective: The aim of radiotherapy is deliver enough doses to the tumor and protecting organs at risk that are around the tumor. In order to get appropriate dose distribution one can use radiation modifiers and compensators. So knowing attenuation coefficient of absorbers is necessary for treatment calculations.Materials and Methods: In this study Mercury was introduced as suitable material for radiotherapy shielding. A new method is presented by physics of interaction of photon with matter and complex integration calculation to calculate attenuation coefficient for any material with different thickness and energies.Results: Radiation quality changes with thickness of absorber and this variation were significant. However, changes in field sizes did not produce any significant variations.Conclusions: Variation of attenuation coefficient with thickness of absorber cannot be ignored and it is necessary for accurate radiotherapy treatment. On the other hand using one number as an attenuation coefficient for radiotherapy compensators or modifiers is not accurate enough and variation of attenuation coefficient with thickness of absorber must be considered in radiotherapy treatment planning systems.

An analytical equation of state by Song and Mason is developed to calculate the PVT properties of Mercury. The equation of state is based on the statistical-mechanical perturbation theory of hard convex bodies and can be written as a fifth-order polynomial in the density. There exists three temperature dependent parameters in the equation of state; the second virial coefficient, an effective molecular volume, and a scaling factor for the average contact pair distribution function of hard convex bodies. The temperature-dependant parameters have been calculated using corresponding-states correlations based on the heat of vaporization and the liquid density at the melting point. The average absolute deviation for the calculated density of Mercury in the saturation and compressed state is 0.38.

Due to hygienic risks of Mercury residues in food and marine originated supplements, measuring total Mercury and methyl Mercury contents of canned tuna as a highly consumable marine food product is essential. In this study, 40 canned Tuna fish (from Persian Gulf) were collected in 2015 and then flame atomic absorption spectrometer (FAAS) and thermo gas chromatography mass spectrophotometry were used to measure total Mercury and methyl Mercury, respectively. The results indicated that the average contents of total Mercury and methyl Mercury of the canned tunas, with 34.2 and 29.5 ppb decrements compared with 2009’s measurement, were 177.4 and 143.7 ppb respectively. The highest concentration of the total Mercury was 315.2 while it was 267.9 ppb for methyl Mercury. This study showed that the content of the Mercury in canned tunas of the Persian Gulf was less than the Maximum Residue Limit (MRL).

Background and aims: Methyl Mercury is a well- known environmental pollutant and toxicant to the nervous tissue, particularly during development of prodecure of brain. Low concentration of methyl Mercury chloride (MMC) can be transferred to the fetus through the placenta and to newborn offspring through dam. This study aimed at investigating the toxicity significant difference effect of methyl Mercury chlyoride on nearborn rat.Methods: In this experimental study 21 adult female Wistar rats were devided in 3 groups, 2 experimental and 1 control group, the experimental groups were inoculated with MMC 0.5 and 4.5 mg/kg on the 15th, 16th and 17th gestation days. On day 25 after birth, 6 newborn rats from each experimental group were anesthetized. Blood samples were collected, alanine amino transferase (ALT), gamma glutamyle transferase (GGT), aspartate amino transferase (AST), alkaline phosphatase (ALP), tri iodo thyronine (T3), thyroxine (T4) and growth hormone (GH) were determined according to routine laboratory methods and the amount of Mercury accumulation in some tissues were measured using atomic absorbtion. Histological examination of the brain, liver and kidney were also performed. The data were analyzed using Kruskal-Wallis and Mann Whitny tests.Results: Serum analysis showed no significant difference in the experimental groups in GGT, AST, ALT, T4 compared to control group (P>0.05). Also ALP, T3 and GH significantly increased compared to the control group (P<0.05). The Mercury accumulation significantly increased retrospectively in brain, thyroid, kidney and liver with the increase in the injection dose (P<0.005). In the histopathologic study of the brain, degeneration and apoptosis were observed.Conclusion: This study showes that exposure to the low doses of induced MMC, reduces T3, growth hormone and it decreases ALP level in experimental groups compared to the control group. It may impair memory, learning and growth.

Background and objectives: Methyl Mercury can carry out harmful effects on the reproductive, respiratory, and nervous system of human. Moreover, Mercury is known as the most toxic heavy metal in nature. Fish and seafood consumption is the major MeHg exposure route for human. The present study tries to cover researches which have been conducted on Mercury levels in 21 species of fish from Persian Gulf, Caspian Sea and Anzali Wetland during the past 6 years, and in addition to stating Mercury level, it provides recommendations about the restriction of monthly fish consumption for each species separately.Material and methods: Fish samples were transferred to the laboratory and stored in refrigerator under-20oC until they were dissected. Afterwards, the muscle tissues were separated and dried. The dried samples were ground and changed into a homogenous powder and then the Mercury concentration rate has been determined by advanced Mercury analyzer, model 254.Results: In general, Mercury contamination in fishes caught from Anzali Wetland was much more than fishes from Caspian Sea. Also, from among all studied fishes, oriental sole (Euryglossa orientalis), caught from Persian Gulf, allocated the most Mercury level to itself with the rate of 5.61ml per kg., therefore, it exercises a severe consumption restriction for pregnant women and vulnerable groups.Conclusion: Based on the calculations, about 50% of fishes, mostly with short food chain, can be easily consumed during the year. However, with regard to Oriental sole (Euryglossa orientalis) and shark (Carcharhinus dussumieri), caught from Persian Gulf, special consideration should be taken in their consumption.On the other hand, careful planning should be made for the high rate of fish consumption among fishing community.

MeHg and total Mercury concentrations were determined in the muscle tissues of four fish species (Cyprinus carpio, Rutilus frisii, Carassius auratus and Esox lucius) from Anzali wetland (Guilan, Iran). Fish with the highest amount of MeHg was selected to determine the thermodynamic parameters of MeHg extraction. The extractions process was performed in the range of temperatures 331.15 to 367.15 K and at atmospheric pressure. Results show the extraction of MeHg from SH groups of sulfhydryl proteins was an endothermic process with a positive value for entropy and Gibbs free energy changes at the room temperature. Significant difference was found between MeHg content at T=367.15 K and other temperatures. Correlation coefficients results showed that the Mercury concentration in muscle tissue was significantly related to the length and weight of fish (p≤0.01). Also, thermodynamic parameters of methylMercury extractions had significant correlation (p≤0.05) with length and weight of the six fish specimen.