Tritium in urine from members of the general public and occupationally exposed workers in Lund, Sweden, prior to operation of the European Spallation Source

A powerful neutron source, the European Spallation Source (ESS), is currently under construction in Lund, Sweden (~90 000 inhabitants). Levels of tritium (3H) in urine were estimated in members of the public in Lund and employees at the ESS using liquid scintillation counting, to obtain baseline levels before the start of operation of the ESS. These were compared with levels in other occupationally exposed radiation workers. Both the spallation reaction in the ESS tungsten target and the activation of various materials by the protons produced by the 5 MW linear accelerator will generate tritium, which will be released into the atmosphere mainly as tritiated water (HTO). Urinary HTO activity concentrations were determined in a total of 55 individuals belonging to four different categories: ESS employees, neighbours of the ESS, members of the general public in Lund and exposed workers from other facilities. The participants were asked to provide information on their beverage intake the day before urine sampling. The urine samples were filtered on activated charcoal and distilled before analysis. The effect of sample preparation on the isotope fractionation of urine samples was investigated by isotope ratio mass spectrometry (IRMS) of 2H/1H, which showed no influence. IRMS was also used to investigate if the ratio between the stable hydrogen isotopes (2H/1H) could provide useful data of the origin, and hence the tritium concentration, of various types of drinking water. Urinary HTO activity concentrations determined using liquid scintillation counting (LSC) were found to be below the minimum detectable activity (MDA) of 2.1 Bq⋅L−1 for most of the participants. Five of the workers actively handling organic tritiated material were found to have activity concentrations between 3.5 and 11 Bq⋅L−1, which were higher than the average value in local tap water of 1.5 ± 0.6 Bq⋅L−1. The results will be used to evaluate the radiological impact on the population from future releases of tritium resulting from the operation of the ESS

The prototyping of a high-resolution neutron activation analysis system - Based on a Pelletron accelerator and fast pneumatic sample-transport

A new neutron activation analysis system is currently being designed at Lund University. The design incorporates a compact accelerator driven neutron source, based on a 3 MV Pelletron accelerator and a pneumatic sample conveyor to transport samples from the neutron source to a measurement station consisting of an array of high-purity Ge γ-ray detectors. A prototype for this new station is currently in operation, with a Genie 16 SODERN neutron generator used in place of the compact accelerator driven neutron source. Preliminary results from the prototype system are presented, alongside qualitative analysis supported by simulations performed in FISPACT-II. The system has been tested with the measurements of Al and In foils, using a PLA sample holder. The results demonstrate that activation products with half-lives of as little as 2 s can be measured. γ-rays from the 2 s isomer, 116n In are clearly observed providing the irradiation and measurement times are appropriately chosen

Layer‑by‑Layer Assemblies Based on a Cationic β‑Cyclodextrin Polymer: Chiral Stationary Phases for Open‑Tubular Electrochromatography

Non-covalent chiral stationary phases for open-tubular capillary electrochromatography (OT-CEC) were developed using polyelectrolyte multilayer (PEM) coatings. These chiral coatings were made by alternately flushing the separation capillary with cationic and anionic polymers using a polymer of trimethylammonium-β-CD (pCD+) as a chiral selector. The layer-by-layer construction was monitored by EOF measurements. To our knowledge, it is the first OT-CEC chiral stationary phase based on a layer-by-layer assembly including an ionic cyclodextrin polymer. The composition of PEM coating was optimized as regards chiral separation. Thus, the influence of the nature of the first adsorbed cationic polymer (pCD+, polyethyleneimine or poly(diallyldimethyl ammonium chloride)) and the influence of the anionic polymer (poly(sodium 4-styrenesulfonate), polycarboxymethyl-β-CD or chondroitin sulfate) were studied with regard to the apparent surface charge and the enantioselective properties of the coatings. Interactions between the studied enantiomers and the internal layers of the stationary phase were pointed out. We found that the optimal stationary phase was based on a pCD+/poly(sodium 4-styrenesulfonate)/pCD+ three-layer coating. This optimal coating was found to be stable as evidenced by the RSD of 2.2 % for the EOF values calculated from five independent analyses. It was effective for the chiral separation of both neutral and anionic solutes