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The existence of natural radioactivity in phosphate fertilizers originates from the rock phosphate that is used as a feed stock for the manufacturing of various types of phosphate fertilizers. Gamma ray activity mass concentrations have been determined in phosphate rock and fertilizer samples collected from different fertilizer manufacturing factories and suppliers in Pakistan. The technique of gamma ray spectrometry was applied using a HPGe (high purity germanium) gamma ray detector coupled with a personal computer (PC) based multichannel analyzer (MCA). The specific activity values of 40K, 226Ra, and 232Th were widely distributed in the rock and fertilizer samples. Activity mass concentrations of 238U (226Ra) in the rock phosphate from Jordan and Pakistan were 428 +/- 11 and 799 +/- 10 Bq kg(-1), respectively, and that in the triple-superphosphate fertilizer was 701 +/- 21 (-1), which was greater than the average values of 238U (226Ra) for other types of fertilizers under study. The concentrations of 40K and 232Th were of the order of background level on the Earth's crust. Chemical analysis for concentration of different constituents in rock phosphate was also carried out. The higher the concentrations of P2O5 and K2O were, the higher the specific activities of 226Ra and 40K were, respectively, in the rocks under study. The amount of radioactivity in the rock phosphate is a source of continuous exposure to radiation, which varies widely depending upon the origin and grade of rock; therefore, radiation dose rate has been estimated. The values of dose rate and other derived quantities were many folds larger than the limits specified for those quantities.

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Granite is an igneous rock that contains natural radioactivity of primordial radionuclides. In Pakistan, granite is distributed in a vast area called the Ambela Granitic Complex (AGC) in North West Frontier Province (NWFP). Granite is a hard rock that exists in different colours and is used to decorate floors, kitchen counter tops, etc. The use of granite in a building as a decor material is a potential source of radiation dose; therefore, natural radioactivity has been measured in 20 granite samples of the AGC with an HPGe (high purity germanium) based gamma ray spectrometer. The average specific activities and their range (given in parentheses) for primordial radionuclides (40)K, (226)Ra and (232)Th were 1218 (899-1927), 659 (46-6120) and 598 (92-3214) Bq kg(-1), respectively. The measured activity concentrations were used for the assessment of hazard indices and radiation dose which were evaluated based on the permissible limits defined for these parameters. The measured specific activities and the derived quantities, hazard indices and radiation dose, have been compared with those given in the literature for these parameters.

Moringa oleifera, also called miracle tree, is a pharmaceutically important plant with a multitude of nutritional, medicinal, and therapeutic attributes. In the current study, an in-vitro-based elicitation approach was used to enhance the commercially viable bioactive compounds in an in vitro callus culture of M. oleifera. The callus culture was established and exposed to different monochromatic lights to assess the potentially interactive effects on biomass productions, biosynthesis of pharmaceutically valuable secondary metabolites, and antioxidant activity. Optimum biomass production (16.7 g/L dry weight), total phenolic contents (TPC: 18.03 mg/g), and flavonoid contents (TFC: 15.02 mg/g) were recorded in callus cultures placed under continuous white light (24 h), and of other light treatments. The highest antioxidant activity, i.e., ABTS (550.69 TEAC µM) and FRAP (365.37 TEAC µM), were also noted under white light (24 h). The analysis of phytochemicals confirmed the significant impact of white light exposures on the enhanced biosynthesis of plant secondary metabolites. The enhanced levels of secondary metabolites, i.e., kaempferol (1016.04 µg/g DW), neochlorogenic acid (998.38 µg/g DW), quercetin (959.92 µg/g DW), and minor compounds including luteolin, apigenin, and p-coumaric acid were observed as being highest in continuous white light (24 h with respect to the control (photoperiod). Similarly, blue light enhanced the chlorogenic acid accumulation. This study shows that differential spectral lights demonstrate a good approach for the enhancement of nutraceuticals along with novel pharmacologically important metabolites and antioxidants in the in vitro callus culture of M. oleifera.