Natural radioactivity of some Egyptian materials used in glasses manufacturing and glass ceramics

Background: the new glasses from harmful environmental waste such as cement dust; limestone phosphate, sand and borax [Genkare] were manufactured. Investigation of the radioactivity present in these materials [Phosphate rock, cement dust, limestone, sand and borax] enables one to assess any possible radiological hazard to humankind by such materials

Materials and Methods: fifteen samples were collected from five locations. Activity measurements have been performed by gamma-ray spectrometer, employing a high-resolution scintillation detector Nal [Tl] crystal 3 ×3 inch. In addition, the radiological hazards were calculated for the investigated samples

Results: the average values of activity ranged from 28 +/- 2 to 163 +/- 12, 2.8 +/- 0.7 to 40 +/- 3 and from 49 +/- 4 to 1337 +/- 74 Bq kg-1 for 226R, 232Th and 40K, respectively. The values of absorbed dose rates, radium equivalent activities and annual effective dose due to 226Ra, 232Th and 40K respectively, are ranged from 22.05 to 101.59 nGy h-1, 45.90 to 224.22 Bq kg-1 and 27.04 to 124.59 micro Sv y-1. In addition, the values of external hazard index, internal hazard index and gamma index have been calculated

Conclusion: according to the obtained results, all materials would not present a significant radiological hazard except phosphate. The results of the study could serve as important baseline radiometric data for future epidemiological studies and monitoring initiatives

Correlation of abdominal ultrasonographic findings with continuous 24-hour PH monitoring oesophageal studies in children with gasrtroesphageal reflux disease [GORD]

Gastro oesophageal reflux [GOR] is a common, benign, usually self limiting condition but gastro oesophageal reflux disease [GORD] is less common and can lead to oesophagitis, pulmonary aspiration and acute life threatening events. The assessment of GOR normally requires invasive techniques. Our objective was to assess the role of gastro oesophageal ultrasound [US] as a screening tool for children with significant GOR compared with 24 hour pH studies. US and pH monitoring was compared retrospectively in 31 symptomatic children who underwent both investigations. Average age of 3.7 years [range 2 months to 11 years]. 16 US was found to be a useful technique with 93% sensitivity, 53% specificity, a low false negative rate of 3% and a negative predictive value of 88% for the detection of significant GOR compared with pH probe studies. Abdominal ultrasound can be a useful non-invasive screening method for the detection of significant GOR allowing more invasive pH probe, studies to be reserved for selected patients