Transatlantic Air Travel in the Third Trimester of Pregnancy: Does It Affect the Fetus?

Most commercial airlines allow pregnant women to fly up to 36 weeks of gestation. Available information suggests that noise, vibration, and cosmic radiation present a small risk for the pregnant air traveler. The goal of the study was to assess the possible effect of transatlantic flights on the condition of the third-trimester fetus. In total, 112 patients were recruited into the study between January 2005 and June 2016. All underwent a transatlantic flight in the third trimester of pregnancy. All underwent nonstress test before and within 12 hours after the transatlantic flight, and 24 hours later. Patients were asked to report changes in fetal movements (FMs), if any, during takeoff, flight itself, and landing. The time of flight varied from 8 to 15 hours; average flight time was 9 ± 3.8 hours. Ninety-eight patients were the passengers of first or business class, and the rest were of economy class. Increased FM during takeoff was reported by 17 patients (15%), no change in FM by 62 (35%), decreased FM by 4 (3.6%). During flight itself, increased FM was reported by 6 pregnant passengers (5.4%), no change in FM by 70 (63%), decreased FM by 8 (7%).

Long-term activation in a 15 MeV radiotherapy accelerator.

The high energy electrons produced by linear accelerators can generate several radioisotopes by means of photonuclear reactions. The activity produced in the head of a 15 MV Mevatron Siemens 77 medical linear accelerator was measured by high resolution gamma-ray spectrometry, during its decommissioning 1 year after the last clinical use. The activity of 54Mn, 57Co, 60Co, 181W, and 65Zn was measured while the activity of other radioisotopes which emit soft beta or gamma rays such as 59Ni, 63Ni, and 55Fe was inferred by appropriate scaling factors. The number of pieces requiring particular care is limited, their mass does not exceed some tens of kilograms, and their volume is of the order of some thousands of cm3. Moreover, these materials are metals and the emitted radiation can be easily shielded, so that storage should not create particular problems.

Secondary photon fields produced in accelerator-based sources for neutron generation.

Neutrons can be produced with low-energy ion accelerators for many applications, such as the characterisation of neutron detectors, the irradiation of biological samples and the study of the radiation damage in electronic devices. Moreover, accelerator-based neutron sources are under development for boron neutron capture therapy (BNCT). Thin targets are used for generating monoenergetic neutrons, while thick targets are usually employed for producing more intense neutron fields. The associated photon field produced by the target nuclei may have a strong influence on the application under study. For instance, these photons can play a fundamental role in the design of an accelerator-based neutron source for BNCT. This work focuses on the measurement of the photon field associated with neutrons that are produced by 4.0-6.8 MeV protons striking both a thin 7LiF target (for generating monoenergetic neutrons) and a thick beryllium target. In both cases, very intense photon fields are generated with energy distribution extending up to several MeV.

A very low-background gamma-ray counting facility in the Baradello underground laboratory.

An underground station for the measurement of low-level radioactivity is in operation in Northern Italy in the town of Como under the Baradello hill. The rock cover is -300 m water equivalent. This paper reports about the preliminary measurements carried out to characterise the site of the Baradello hill and the installation of a high-purity Ge detector with a radio-pure copper shielding. Features and levels of the achieved background are reported and discussed, in comparison with other above ground and underground low-radioactivity stations. Sensitivities to radioactivity in typical environmental matrices are evaluated, confirming the very low-gamma background attained in the laboratory.

Characterization of an underground site in Northern Italy in view of low radioactivity measurements.

A low background station for the measurement of low level radioactivity is under development in Northern Italy. The rock cover is about 300 m water equivalent. We report and discuss measurements of radon concentration in air and of gamma, muon and neutron fluxes performed in the neighborhood of the station site. We present and apply a simple analytical model capable to disentangle the contribution to the measured gamma activities due to 222Rn in air from the one due to 238U and its daughters in the rocks.

Determination of P in bones and of Al and Si in pottery by activation with reactor neutrons.

This note describes the results obtained in activation analysis with reactor neutrons. Particular attention is devoted to the analysis of P in bones, and of Al and Si in pottery. Other applications are also discussed.