Radiocarbon dating of modern peat profiles: Pre- and post-bomb C-14 variations in the construction of age-depth models

We present studies of 9 modern (up to 400-yr-old) peat sections from Slovenia, Switzerland, Austria, Italy, and Finland. Precise radiocarbon dating of modern samples is possible due to the large bomb peak of atmospheric 14C concentration in 1963 and the following rapid decline in the 14C level. All the analyzed 14C profiles appeared concordant with the shape of the bomb peak of atmospheric 14C concentration, integrated over some time interval with a length specific to the peat section. In the peat layers covered by the bomb peak, calendar ages of individual peat samples could be determined almost immediately, with an accuracy of 23 yr. In the pre-bomb sections, the calendar ages of individual dated samples are determined in the form of multi-modal probability distributions of about 300 yr wide (about AD 16501950). However, simultaneous use of the post-bomb and pre-bomb 14C dates, and lithological information, enabled the rejection of most modes of probability distributions in the pre-bomb section. In effect, precise age-depth models of the post-bomb sections have been extended back in time, into the wiggly part of the 14C calibration curve.

High-resolution AMS (super 14) C dating of post-bomb peat archives of atmospheric pollutants.

Peat deposits in Greenland and Denmark were investigated to show that high-resolution dating of these archives of atmospheric deposition can be provided for the last 50 years by radiocarbon dating using the atmospheric bomb pulse. (super 14) C was determined in macrofossils from sequential one cm slices using accelerator mass spectrometry (AMS). Values were calibrated with a general-purpose curve derived from annually averaged atmospheric (super 14) CO (sub 2) values in the northernmost northern hemisphere (NNH, 30 degrees -90 degrees N). We present a through review of (super 14) C bomb-pulse data from the NNH including our own measurements made in tree rings and seeds from Arizona as well as other previously published data. We show that our general-purpose calibration curve is valid for the whole NNH producing accurate dates within 1-2 years. In consequence, (super 14) C AMS can precisely date individual points in recent peat deposits within the range of the bomb-pulse (from the mid-1950s on). Comparing the (super 14) C AMS results with the customary dating method for recent peat profiles by (super 210) Pb, we show that the use of (super 137) Cs to validate and correct (super 210) Pb dates proves to be more problematic than previously supposed. As a unique example of our technique, we show how this chronometer can be applied to identify temporal changes in Hg concentrations from Danish and Greenland peat cores.

Reconnaissance survey of Galveston Bay sediments for selective nonresidual trace metals

The nonresidual concentrations of five trace metals were determined for 322 sediments that were the product of a systematic sampling program of the entire Galveston Bay system. The nonresidual component of the trace metal concentration (e.g. that fraction of the metals that can be relatively easily removed from the sediments without complete destruction of the sediment particle) was considered to be more indicative of the anthropogenic metal pollution that has impacted the Galveston Bay ecosystem.^ For spatial analysis of the metal concentrations, the Galveston Bay system was divided into nine bay-areas, based on easily definable geological and geographical characteristics. Isopleth mapping analyses of these metal concentrations indicated a direct relationship with the $<$63$\mu$m fraction of the sediment (%FINE) in all of the bay areas. Covariate regression analyses indicated that position of the sediment within the Galveston Bay system (e.g. bay-area) was a better predictor of metal concentration than %FINE. Analysis of variance of the metals versus the bay-areas indicated that the five metals maintained a relatively constant order and magnitude of concentration for all the bay-areas.^ The major shipping channels of the Galveston Bay system, with their associated vessels and transported materials, are a likely source of metal pollution. However, these channels were not depositional corridors of high metal concentration. All metal concentration highs were found to be located away from the channels and associated with %FINE highs in the deeper portions of the bay-areas.^ Disturbance of the sediments, by the proposed widening and deepening of these channels, is not predicted to remobilize the trace metals. A more likely adverse effect on the health of the Galveston Bay ecosystem would come from the increase in turbidity of the water due to the dredging and in an extension of the salt water wedge farther north into the bay system. ^

Greetings: 50 years of Atomic Bomb Casualty Commission–Radiation Effects Research Foundation studies

The Atomic Bomb Casualty Commission was established in Hiroshima in 1947 and in Nagasaki in 1948 under the auspices of the U.S. National Academy of Sciences to initiate a long-term and comprehensive epidemiological and genetic study of the atomic bomb survivors. It was replaced in 1975 by the Radiation Effects Research Foundation which is a nonprofit Japanese foundation binationally managed and supported with equal funding by the governments of Japan and the United States. Thanks to the cooperation of the survivors and the contributions of a multitude of scientists, these studies flourish to this day in what must be the most successful long-term research collaboration between the two countries. Although these studies are necessarily limited to the effects of acute, whole-body, mixed gamma-neutron radiation from the atom bombs, their comprehensiveness and duration make them the most definitive descriptions of the late effects of radiation in humans. For this reason, the entire world relies heavily on these data to set radiation standards. As vital as the study results are, they still represent primarily the effects of radiation on older survivors. Another decade or two should correct this deficiency and allow us to measure definitively the human risk of heritable mutation from radiation. We look to the worldwide radiation and risk community as well as to the survivors who have contributed so much to what has been done already to accomplish this goal.

The Atomic Bomb Casualty Commission in retrospect

For 50 years, the Atomic Bomb Casualty Commission (ABCC) and its successor, the Radiation Effects Research Foundation (RERF), have conducted epidemiological and genetic studies of the survivors of the atomic bombs and of their children. This research program has provided the primary basis for radiation health standards. Both ABCC (1947–1975) and RERF (1975 to date) have been a joint enterprise of the United States (through the National Academy of Sciences) and of Japan. ABCC began in devastated, occupied Japan. Its mission had to be defined and refined. Early research revealed the urgent need for long term study. In 1946, a Directive of President Truman enjoined the National Research Council of the National Academy of Sciences to develop the program. By 1950, ABCC staff exceeded 1,000, and clinical and genetic studies were underway. Budgetary difficulties and other problems almost forced closure in 1953. In 1955, the Francis Report led to a unified epidemiological study. Much progress was made in the next decade, but changing times required founding of a binational nonprofit organization (RERF) with equal participation by Japan and the United States. New programs have been developed and existing ones have been extended in what is the longest continuing health survey ever undertaken.

Le principe de reconnaissance mutuelle dans la libre prestation de services = The principle of mutual recognition in the free provision of services. Research Papers in Law 2/2009

No abstract.

Stigmatisation of EU mobile citizens: a ticking time bomb for the European project. EPC Commentary, 24 January 2014

The 2013 European Year of Citizens was profoundly marked by escalating attacks against one of the EU’s major achievement for EU citizens: freedom of movement. In April 2013, Home Affairs Ministers from Austria, Germany, the Netherlands and the UK were party to a letter claiming that “a significant number of new immigrants draw social assistance in the host countries, frequently without genuine entitlement, burdening host societies’ social welfare systems”. This letter laid the groundwork for a “battle plan”, presented by David Cameron in November, which aimed to make the free movement of persons “less free” and put forward the idea of capping “EU migration”. Furthermore, in December, the German conservative Christian Social Union (CSU) took up a similar petty political discourse. After the end of the transitional period for Romania and Bulgaria on 1 January 2014, the debate continues with Chuka Umunna (British Labour Party) proposing to restrict the freedom of movement to highly skilled EU citizens and to citizens in possession of a firm job offer. Alongside this, the German Chancellor, Angela Merkel announced the formation of a committee to investigate “poverty migration” in Germany. This wave of resentment has been more recently followed by the UK Prime Minister David Cameron, expressing his intention to re-negotiate EU law in order to be able to withdraw child benefits from EU citizens working in the UK, citing Polish citizens working in the UK as an example. Seeing this as a stigmatisation of the Polish population, the Polish foreign minister, Radosław Sikorski, qualified Cameron’s discourse as “unacceptable”. The debate over limiting freedom of movement has continuously escalated and reached a worrying level. With the EP elections approaching in May 2014, this debate is likely to become worse.