LC-MS/MS Investigation of nitrosamine impurities in certain Sartan group medicinal products available in Istanbul, Türkiye

Nitrosamines (NAs) are molecules that include the nitroso functional group. In 2018, the US Food and Drug Administration (FDA) received its first report of NAs in pharmaceuticals. The fact that NA impurities are likely human carcinogens is relevant to these compounds. Furthermore, prolonged exposure to NA contaminants above safe limits may raise the risk of cancer. The goal of this article was to assess the amounts of six different NAs in Sartan group medicines purchased from formal pharmacies in Istanbul, Türkiye, using a validated LC-MS/MS assay. An LC-MS/MS-based analytical assay was undertaken. The separation was performed with a HR ODS 150mm×3.0mm and 5-analytical columns, providing effective separation of major peaks from NA impurities. In mobile phase A, formic acid was 0.10% in water, while in mobile phase B, formic acid was 0.10% in methanol. The flow rate was 0.4mL/minute, and the total runtime was 18minutes with the gradient elution mode. The validation was conducted in line with ISO/IEC 17025 requirements. Up to 100μg/L, linearity was determined using correlation coefficients (r2>0.995) for all NAs. The limit of quantification values for all NAs analyses were below 1.0μg/L. The mean recovery value obtained during the spike experiment was 95.18%, demonstrating the accuracy of the procedure. In addition, the accuracy was shown by a certified reference analysis, which yielded relative standard deviation and relative error values of 1.82% and 3.34%, respectively. During the intermediate precision testing, bias and relative standard deviation were 0.96 and 2.87%, respectively. Of the 75 study samples involving Sartan group medical products, no nitrosamine impurities were detected, demonstrating that pharmaceutical companies have adequate medication safety precautions in place in accordance with FDA and European Medicines Agency (EMA) regulations published to prevent NA contaminants in human medicinal products.

Measurement of enhanced radium isotopes in oil production wastes in Turkey

Gamma dose rates of oil production equipment and wastes were measured externally by survey meter. They were found to be between 0.2 μSv h(-1) and 25.7 μSv h(-1). Activity concentrations of radium isotopes in crude oil, scale, sludge, contaminated soil and water samples were determined by gamma spectrometric method. Activity concentrations of (224)Ra, (226)Ra and (228)Ra in samples varied from MDA to 132,000 Bq kg(-1). Radium isotopes enriched up to 14,667 times in scale samples. The highest value of (226)Ra was found to be 35,122 ± 1,983 Bq kg(-1) for sludge samples. Activity concentrations of a considerable number of samples were found to be higher than the exemption level recommended by IAEA. Measurement results revealed that oil production wastes caused soil contamination up to 70,483 Bq kg(-1). They may pose a radiological risk for workers and members of the public.

Unintentional irradiation of conceptus by diagnostic imaging examinations in Turkey

Exposure of the fetus to medical radiation sources during the diagnostic procedures without intention is one of the most significant concerns in the medical community. In this study, 45 conventional X-ray and computed tomography (CT) examinations of the women who were unaware of their pregnancy were investigated. Effective doses and fetal doses were calculated for each application by using PCXMC and ImPACT CT scan software. The exposure of abdominal CT and abdominal conventional X-ray examinations was found to be over the literature for both the range and the average values. Average effective dose for abdominal CT examinations was calculated to be ∼3.1 times higher than that in the literature. For abdominal CT and conventional X-ray examinations, the mean fetal doses were found to be ∼3.5 times and ∼5.4 times higher than those in the literature, respectively.

Activity concentrations of 224Ra, 226Ra, 228Ra and 40K radionuclides in refinery products and the additional radiation dose originated from oil residues in Turkey

A total of 56 crude oil, refinery product, waste water, sludge and scale samples collected from three refineries were measured by gamma-ray spectrometry. Except for nine samples, all refinery product samples were found to have activity concentrations below the minimum detectable activity (MDA) values. The maximum (224)Ra, (226)Ra, (228)Ra and (40)K activity concentrations in crude oil and refinery product samples were measured as 11.7 ± 4.5, 14.9 ± 3.5, 11.6 ± 4.5, 248.5 ± 18.5 Bq kg(-1), respectively. The maximum (224)Ra, (226)Ra, (228)Ra and (40)K activity concentrations in scale, sludge and water samples were measured as 343.7 ± 11.8, 809.2 ± 29.0, 302.5 ± 21.6, 623.0 ± 80.9 Bq kg(-1), respectively. Radium equivalent activities of the residue samples were calculated up to 1241.8 ± 42.4 Bq kg(-1). The maximum activity concentration index and the alpha index were found to be 4.2 and 4.0, respectively. The annual effective doses of residue samples were calculated below the permitted dose rate for the public, i.e. 1 mSv y(-1).