فهرست مطالب nasrin fathabadi

Mercury is a one of the pollutant that can cross the placenta. Contamination by mercury in mothers and their neonates is associated with many problems.

This study aimed to compare mercury levels of cord blood in term and preterm neonates in Akbarabadi Hospital, Tehran, Iran, 2014.

In this analytical cross-sectional study, we evaluated 50 term and 50 preterm neonates who were born in Akbarabadi Hospital in 2014. Necessary information including mother’s age, location, mother’s job, use of amalgam, use of fish, use of blood products and level of mercury were collected. Data were entered into SPSS V.16 and analyzed.

Mean age of mothers was 30.1 (SD = 6.4) years. Location in 86 (86%) were Tehran and in 14 (14%) were out of Tehran. Mean of mercury in neonatal cord blood was 2.7 (SD = 1.3) g/L. There was significant difference between this mean in term and preterm neonates (P value = 0.009), while mean of mercury level in term neonates was 2.3 (SD = 0.7)g/L and in preterms was 3 (SD = 1.7)g/L. Mean of using fish in term neonates was1.2 (SD = 1.3) and in preterms was 1.6 (SD = 2.5). We could not find any significant difference between mercury level and using amalgam, fish and blood products in term and preterm neonates (P value > 0.05).

Mercury level of cord blood in our study was higher compared to other studies, although it is not in the level of toxicity. Also we found that mercury level in preterm neonates is significantly higher than term neonates, therefore evaluating factors affecting mercury levels in neonates is essential.

The coastal area of ​​Ramsar in northern of Iran located in the province of Mazandaran has been known as the highest levels of natural radiation background in the world. The background radiation is mainly due to the presence of radioactive isotopes of the radium element and its decay products, which is brought to the surface by hot springs. In this study, the indoor gamma dose rate in Ramsar was directly measured and the public annual effective dose due to indoor gamma radiation was calculated. To measure the gamma dose rate, a portable gamma spectrometer with sodium iodide detector (Na I) was used. 100 houses are randomly selected and the measurements were carried out at one meter height above the ground surface in each place, which was mostly occupied by people in each house. The public annual effective dose due to indoor gamma exposure was calculated. The maximum, minimum, and average dose rates were 222 nSv h-1, 44 nSv h-1 and 94 nSv h-1, respectively. The highest, lowest, and average public annual effective dose of Ramsar residents due to indoor gamma exposure were 1.55, 0.31 and 0.66 mSv, respectively. The results of this study indicate that average of the public annual effective dose of Ramsar people due to indoor gamma exposure is equal to 0.66 mSv and it is approximately 1.6 times greater than the worldwide average exposure to indoor gamma radiation reported by the United Nations Scientific Committee on the Effects of Atomic Radiation (0.41 mSv). In addition, it is not significantly different from the other reported results (average of 0.7 mSv) for the homes in normal radiation background areas in Ramsar.

Radon is a radioactive gas and the second leading cause of death due to lung cancer after smoking. Ramsar is known for having the highest levels of natural background radiation on earth. In this research study, 50 stations of high radioactivity areas of Ramsar were selected in warm season of the year. Then gamma dose and radon exhalation rate were measured. Results showed that gamma dose and radon exhalation rate were in the range of 51-7100 nSv/hr and 9-15370 mBq/m2s, respectively. Compare to the worldwide average 16 mBq/m2s, estimated average annual effective of Radon exhalation rate in the study area is too high.