222Rn exposure, as the second risk factor for lung cancer can also damage DNA, penetrate the stomach and move through the human body via the bloodstream 5, 8. The inhalation and ingestion are the main pathways of exposure to 222Rn the occurrence of high levels of this carcinogenic agent in indoor air and groundwater resources give rise to human internal exposure 16, 17, 18, 19. Radon is characterized with long-term half-life and capability of alpha particle emission, causing lung, blood and gastrointestinal cancer in humans during long term exposure 5, 16. 222Rn is recognized as the colorless, tasteless, and odorless radioactive gas with half-life of 3.82 days 14, 15. Radon gas is derived from soil, rock, and sediments and commonly observed in the groundwater due to high solubility (510 cm 3 L −1) and density (9.73 g L −1) 10, 11, 12, 13. Radon (222Rn), as the heaviest noble gas, which is produced via alpha decay of 238U is naturally ubiquitous in the environments 222Rn alone comprises 50% of total natural radiation 8, 9. However, artificial radionuclide fallouts caused by accidents and nuclear explosion can contaminate the water resources and environment which human live 6, 7. The naturally occurring sources include the 238U and its daughter’s 226Ra and 222Rn, commonly observed in water resources, rocks and soil 4, 5. Radioactive materials are commonly introduced into the environment via naturally occurring sources and man-made or artificial radionuclide fallouts 3, 4. The environmental sources, especially groundwater drawn from granitic and metamorphic rocks are considered as the primary source of radioactivity 1, 2. Overall, this study indicated that the Iranian people receive no significant radiological risk due to exposure to radon concentration in bottled water brands common consumed in Iranian market. The mean annual effective dose due to ingestion of radon in bottled water for adults, children, and infants were estimated to vary from 5.30 × 10 −4 mSv −1, 4.90 × 10 −4 mSv −1, and 2.15 × 10 −4 mSv −1, respectively. The annual effective dose of 222Rn due to ingestion bottled water was also evaluated in this research. The measured radon concentration ranged from 0.003 to 0.618 Bq L −1 in bottled water samples, which were much lower than the recommended value for radon in drinking water by WHO (100 Bq L −1) and United states environmental protection agency (USEPA) (11.1 Bq L −1). The 222Rn concentration in 70 bottled water samples were measured by the sniffing mode technique and RTM 1688-2 (SARAD, Germany) in immediate sampling time and 3 months later for determination of radon decay. I know Ted uses it as well as other players… maybe a question direct to him on what he likes best and why is in order.A comprehensive study was made to measure the radon concentration in bottled water available in Iran market. I have mine set to display the library as a Windows tree structure… I like it and find no reason to change players. However, wierder things have happened in this audio world… so… to each his/her own.īTW, foobar has super-fast database organization and management… I don’t know if others are as fast/good, but years ago, foobar was peerless in this aspect. The Direct Stream DAC and Junior take great pains to eliminate jitter and other bit stream related issues. Regarding sound… if the player is passing a bit-perfect stream, it should sound no different from other bit-perfect players. If you are not getting bit-perfect pass through, then check if you have Windows volume up to 100… windows kernal does evil to a bit stream. Playing these files will light up on your display (senior or junior) and let you know if you are getting bit-perfect pass through. PS Audio has files you can play to determine if your system is bit perfect. The Geek Illuminati notes that it is very lite on computer resources. It also has a sliding buffer size tool to help with any juttering you may have using an older, slower computer. I have it configured with a dropdown to select output drivers with a click, so I can select output between my PS Audio DAC, and my Woo Audio headphone DAC/Amp. Further, it has a zillion plugins to play all kinds of crazy files and has file utilities. The good is that you can make it look and handle anyway you like. The challenge with Foobar is that it is a geek’s tool and requires some configuration to look good, and for that it helps to have some computer savvy. It is fully bit-perfect, but you can install digital equalizer plug-ins if you like. Sorry, I don’t mean to hijack this thread, but I do want to post that there are other options for a player. If anyone is interested in using Foobar with Windows, I can provide to you my configuration files to get you up and running in no time. BTW, yes I am a Foobar evangelist (it is free).
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