Separation, reserve estimation and radioactivity responsibility of the economic heavy minerals of East El- Arish black sand, North Sinai, Egypt.

Multi-heavy mineral separation techniques like density, magnetic, and electromagnetic techniques are followed by picking, grain counting, and mineralogical examinations conducted with an environmental scanning electron microscope (ESEM). These techniques have been applied to several drill hole (well) composite samples representing beach sand and dunes of East El-Arish area, North Sinai, Egypt. The results explain the remarkable enrichment in total heavy minerals (THM) of beach sand (4.4%) compared to sand dunes (2.6%): this is due to the natural concentration of the currents of the Mediterranean Sea. After characterizing the heavy minerals in terms of the abundance of each mineral species, the mean values of content relative to total economic heavy minerals (TEHM) were determined as 70.03% ilmenite, 3.81% leucoxene, 3.03% magnetite, 8.7% garnet, 10.6% zircon, 3.13% rutile, 0.37% monazite, and 0.31% titanite in the sand dune samples. The total economic heavy minerals in the beach samples were 64.08% ilmenite, 1.6% leucoxene, 2.84% magnetite, 18.16% garnet, 10.4% zircon, 2.18% rutile, 0.61% monazite, and 0.13% titanite. Monazite, thorite, zircon, and apatite are the main radioactive minerals in the study area. The combination of two specific characteristics of the studied monazite (relatively high Th-U content and high frequency) makes monazite the main contributor to radioactivity of the study area.

Radioactive risk assessment of beach sand along the coastline of Mediterranean Sea at El-Arish area, North Sinai, Egypt.

Beach sand includes various levels of natural radioactivity, which can cause health effects. The natural radioactivity was measured in the beach sand along the coastline of the Mediterranean Sea at the east of the El-Arish area, Egypt. Using the HPGe spectrometer, the contribution of radionuclides 226Ra, 232Th and 40K in the gamma emitted radiation illustrated that the 226Ra, 232Th and 40K activity concentrations are 8.8 ± 3.9, 30.8 ± 12.2 and 106.9 ± 46.8 Bq kg-1, respectively, which is lower than the reported worldwide limit 33, 45 and 412 Bq kg-1. The radioactive hazards associated with the beach sand along the coastline of the Mediterranean Sea at the east of the El-Arish area were investigated. The obtained results among the radiological hazard parameters, the radium equivalent content (Raeq), the absorbed dose rate (Dair), annual effective dose (AED), external (Hex) and internal (Hin) hazard indices were estimated. Moreover, the excess lifetime cancer risk (ELCR) and the annual gonadal dose equivalent (AGDE) were also computed and illustrated their values less than the recommended levels. Multivariate statistical approaches like Pearson correlation, the principal component analysis (PCA) and the hierarchical cluster analysis (HCA) were applied to investigate the correlation between the radionuclides and the corresponding radiological hazard variables. Based on the statistical analysis, the 226Ra and 232Th mainly contribute to the radioactive risk of beach sand. Finally, no significant risk of the public associated with utilizing beach sand in building materials.

Waterborne outbreak of Campylobacter enteritis.

A report is given on an outbreak of enteritis which occurred in July 1982 in a kibbutz near Jerusalem. About 150 of the 512 inhabitants were affected. Campylobacter jejuni was isolated from ten out of 42 stool samples examined toward the end of the outbreak. No other enteric pathogen was found. Strong circumstantial evidence indicated an association between the outbreak and the use of water from an unprotected reservoir, but no bacteriological confirmation was obtained.