2011 ◽  
Author(s):  
Kristjen B. Lundberg ◽  
Lawrence J. Sanna ◽  
Craig D. Parks ◽  
Edward C. Chang

2021 ◽  
Vol 33 (1) ◽  
Author(s):  
Johannes Haedrich ◽  
Claudia Stumpf ◽  
Michael S. Denison

Abstract Background Low maximum and action levels set by the European Union for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in pig meat (pork) have led to a demand for reliable and cost-effective bioanalytical screening methods implemented upstream of gas chromatography/high-resolution mass spectrometry confirmatory technology, that can detect low levels of contamination in EU-regulated foods with quick turn-around times. Results Based on the Chemically Activated LUciferase gene eXpression (CALUX) bioassay, extraction and clean-up steps were optimized for recovery and reproducibility within working ranges significantly lower than in current bioassays. A highly sensitive “3rd generation” recombinant rat hepatoma cell line (H4L7.5c2) containing 20 dioxin responsive elements was exposed to pork sample extracts, and their PCDD/Fs and DL-PCBs levels were evaluated by measuring luciferase activity. The method was validated according to the provisions of Commission Regulation (EU) 2017/644 of 5 April 2017 with spiking experiments performed selectively for PCDD/Fs and DL-PCBs and individual calibration for PCDD/Fs, DL-PCBs and the calculated sum of PCDD/Fs and DL-PCBs. The resulting performance parameters met all legal specifications as confirmed by re-calibration using authentic samples. Cut-off concentrations for assessing compliance with low maximum levels and action levels set for PCDD/Fs and DL-PCBs within a range of 0.50–1.25 pg WHO-TEQ/g fat were derived, ensuring low rates of false-compliant results (ß-error < 1%) and keeping the rate of false-noncompliant results well under control (α-error < 12%). Conclusions We present a fast and efficient bioanalytical routine method validated according to the European Union’s legal requirements on the basis of authentic samples, allowing the analyst to reliably identify pork samples and any other EU-regulated foods of animal origin suspected to be noncompliant with a high level of performance and turn-around times of 52 h. This was facilitated in particular by a quick and efficient extraction step followed by selective clean-up, use of a highly sensitive “3rd generation” H4L7.5c2 recombinant rat hepatoma cell CALUX bioassay, and optimized assay performance with improved calibrator precision and reduced lack-of-fit errors. New restrictions are proposed for the calibrator bias and the unspecific background contribution to reportable results. The procedure can utilize comparably small sample amounts and allows an annual throughput of 840–1000 samples per lab technician. The described bioanalytical method contributes to the European Commission's objective of generating accurate and reproducible analytical results according to Commission Regulation (EU) 2017/644 across the European Union.


2007 ◽  
Vol 127 (1-4) ◽  
pp. 411-414 ◽  
Author(s):  
O. Kurihara ◽  
C. Takada ◽  
K. Takasaki ◽  
K. Ito ◽  
T. Momose ◽  
...  

2018 ◽  
Vol 53 (3) ◽  
pp. 199-206 ◽  
Author(s):  
F. Otoo ◽  
E.O. Darko ◽  
M. Garavaglia ◽  
C. Giovani ◽  
S. Pividore ◽  
...  

Indoor radon concentration for annual, rainy and dry season have been studied in 228 buildings which includes bedroom, kitchen, sitting room, laboratories and offices in Accra metropolis of Greater Accra of Ghana. The passive radon CR-39 SSNTD was used for this study. The cumulative frequency distribution, normalizing Q-Q plots, Kolmogorov-Smirnov and Shapiro-Wilk statistical test showed that the result of both workplaces and dwellings are not normally distributed. The strong positive correlation between the two seasons occurred at 95% confidence level with 2 tailed. The rainy season recorded highest coefficient variation of r2 = 0.982. Statistical analysis of median (39.3), AM (103.4), GM (57.9) and GSD (3.2) for rainy season were greater than that of the dry season of median (26.9), AM (88.2), GM (49.2) and GSD (2.8) respectively. Rainy season was found to contain high radon concentrations than the dry season for all the studied locations. In general, workplace had radon concentration far greater than dwellings. The results obtained from this study ranged between 13.6 to 533.7 Bq/m3, out of which 9.6%, 12.7% and 3.5% were found to be greater than action levels proposed by WHO, EC and ICRP.


1990 ◽  
Vol 11 (2) ◽  
pp. 95-102 ◽  
Author(s):  
K. C. YOUNG ◽  
K. KOURIS ◽  
M. AWDEH ◽  
H. M. ABDEL-DAYEM
Keyword(s):  

2020 ◽  
Vol 13 ◽  
pp. 120
Author(s):  
C. A. Papachristodoulou ◽  
K. G. Ioannides ◽  
K. C. Stamoulis ◽  
D. L. Patiris ◽  
S. B. Pavlides

An investigation of atmospheric radon levels in the Perama Cave, North-western Greece, has been carried out using CR-39 detectors. The detectors were placed at various locations along the guided cave pathway and exposed during different sampling periods. Mean concentrations amounting to 925±418 and 1311±352 Bq m-3 were recorded in the summer and winter months, respectively. The quantification of effective doses from radon daughters' inhalation was important, as the Perama Cave is one of the most popular in Greece, attracting more than 85,000 tourists per year. Due to the short duration of the guided tour along the cave, exposure of tourists was found to be insignificant, lying below 5.1 μSv per visit. Permanent cave guides receive doses ranging from 4.2 to 5.9 mSv y-1. Considering the ICRP-65 recommendation that action levels in dwellings and workplaces should be set between 3 and 10 mSv y-1 untertaking remedial measures to reduce the exposure of cave staff may be appropriate.


2004 ◽  
Vol 4 (4) ◽  
pp. 143-154 ◽  
Author(s):  
R. Appleyard ◽  
K. Ball ◽  
F. E. Hughes ◽  
W. Kilby ◽  
R. Nicholls ◽  
...  

Purpose: Having previously reviewed the implementation of systematic in vivo dosimetry at the Norfolk and Norwich Hospital this paper examines the results of entrance dose measurements for specific sites/techniques and determines whether different action/alert protocols are required for these different categories.Methods and materials: Entrance dose measurements using p-type diodes were analysed for the following treatment categories: Breast, head and neck in beam direction shell, abdomino-pelvic and intrathoracic. A 4% tolerance was applied.Results: Mean deviations from expected dose and proportion of measurements exceeding tolerance were: Breast: +1.15%±3.04% (1SD), 238/1073≥4%; Head and neck: +0.35%±2.20% (1SD), 21/326≥4%; Abdomino-pelvic: +0.52%±2.75% (1SD), 93/712≥4%; Intrathoracic: −0.01%±2.75% (1SD), 22/119≥4%. Significant improvements in results for breast patients were noted following the introduction of a commercial breast board. The results for abdomino-pelvic patients confirmed a substantial variation in diode response under short FSD, wedged fields at 16MV (that had not been corrected for). The statistical uncertainty in dose measurement for each treatment category was calculated in order to assist determination of appropriate tolerance levels.Conclusions: A blanket tolerance of 4% was generally too low given the extent of measurement uncertainty. The relatively high number of readings outside tolerance where identification of errors was difficult/impossible resulted in inconsistent application of the action protocol. Some widening of tolerances is likely to improve quality of procedure and treatment. Appropriate action levels are recommended for each treatment category.


PEDIATRICS ◽  
1992 ◽  
Vol 89 (5) ◽  
pp. 827-829
Author(s):  
AUDREY K. BROWN ◽  
DANIEL S. SEIDMAN ◽  
DAVID K. STEVENSON

All seems infected that th' infected spy, As all looks yellow to the jaundiced eye. —Alexander Pope An Essay on Criticism, 1711 We take note of Alexander Pope's admonition, and we are reminded by others that, from their perspective, the evidence is unconvincing that moderate neonatal hyperbilirubinemia adversely affects the neurodevelopmental outcome of healthy, term infants. Moreover, although there is ample evidence that high levels of bilirubin may be associated with neurologic injury, a linear relationship between neonatal serum bilirubin levels and long-term neurodevelopmental impairment does not seem to exist.1 Such observations have been recognized for some time2,3 and have encouraged some of our colleagues to propose new guidelines for the treatment of jaundice in well, term infants.4,5


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