Levels of omega 3 fatty acids, vitamin D, dioxins and dioxin-like PCBs in oily fish; a new perspective on the reporting of nutrient and contaminant data for risk-benefit assessments of oily seafood.

Oily seafood is an important food source which contains several key nutrients beneficial for human health. On the other hand, oily seafood also contains persistent organic pollutants (POPs), including the dioxin-like compounds (DLCs) polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDD/Fs) and dioxin-like-polychlorinated biphenyls (dl-PCBs), potentially detrimental to human health. For a comprehensive comparison of the beneficial and potentially adverse health effects of seafood consumption, risk-benefit analyses are necessary. Risk-benefit analyses require reliable quantitative data and sound knowledge of uncertainties and potential biases. Our dataset comprised more than 4000 analyses of DLCs and more than 1000 analyses each of docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and vitamin D in the three most important Norwegian commercial oily seafood species: Atlantic herring (Clupea harengus), Atlantic mackerel (Scomber scombrus) and farmed Atlantic salmon (Salmo salar). The levels of several DLC congeners were below the limit of quantification (LOQ), making estimation of true levels challenging. We demonstrate that the use of upper bound substitution of censored data will overestimate, while lower bound substitution will underestimate the actual levels of DLCs. Therefore, we implement an alternative robust statistical method by combining Maximum Likelihood Estimation, Regression on Order Statistics and Kaplan-Meier analyses, which is better suited for providing estimations of levels of these contaminants in seafood. Moreover, we illustrate the impact of the toxic equivalency factor (TEF) system on estimation of the sums of DLCs by comparing the TEF system to an alternative system of relative effect potency (REP) factors (Consensus Toxicity Factors). The levels of nutrients and contaminants were related to adequate intake (AI) and tolerable weekly intake (TWI), respectively. We used AI and the TWI values established by the European Food Safety Authority (EFSA). The benefit and the risk were further viewed in the context of the Norwegian average intake of oily fish, and the Norwegian governmental official dietary recommendations of oily fish. Our results showed that both benefit and risk are met at the levels found of nutrients and DLCs in oily seafood. The comprehensive quantitative data presented here will be a key for future risk-benefit assessment of oily fish consumption. Together, our results underline that a refined formalized integrative risk-benefit assessment of oily fish in the diet is warranted, and that the data and methodology presented in this study are highly relevant for future integrated and multidisciplinary assessment of both risks and benefits of seafood consumption for human health.

Age and IQ Explained Working Memory Performance in a RCT with Fatty Fish in a Group of Forensic Inpatients.

OBJECTIVES: To investigate the effect of a long-term fatty fish intervention on a pure cognitive mechanism important for self-regulation and mental health, i.e. working memory (WM), controlling for age and IQ. DESIGN: A randomized controlled trial. SETTING: A forensic facility. PARTICIPANTS: Eighty-four young to middle aged male forensic inpatients with psychiatric disorders. INTERVENTION: Consumption of farmed salmon or control meal (meat) three times a week during 23 weeks. MEASUREMENT: Performance on WM tasks, both accuracy and mean reaction time, were recorded pre and post intervention. RESULTS: Performance on a cognitive functioning tasks taxing WM seemed to be explained by age and IQ. CONCLUSION: Fatty fish consumption did not improve WM performance in a group of young to middle aged adults with mental health problems, as less impressionable factors such as aging and intelligence seemed to be the key components. The present study improves the knowledge concerning the interaction among nutrition, health and the aging process.

Arsenic in seafood is associated with increased thyroid-stimulating hormone (TSH) in healthy volunteers - A randomized controlled trial.

BACKGROUND: Exposure to exogenous elements like arsenic (As) may influence thyroid enzymes, thyroid-stimulating hormone (TSH), and the two principal thyroid hormones, free thyroxine (FT4) and free triiodothyronine (FT3), but little is known about how this is related to organic arsenicals, the main form in seafood. AIM: To investigate whether a high intake of dietary arsenic from seafood can impact thyroid function and thyroid hormones by examining possible associations with changes in TSH, FT4, FT3 and the FT4:FT3-ratio in plasma. METHODS: Thirty-eight healthy subjects were randomized into four groups. During a 14-day semi-controlled dietary study, the subjects ingested daily portions of either 150g cod, salmon, blue mussels or potato (control). Plasma concentrations of total As, FT3, FT4, TSH and selenium (Se), and urinary concentrations of iodine were monitored. RESULTS: Plasma concentrations of TSH increased significantly in all seafood groups. The change in plasma As, with different coefficients for each seafood group, was the dominant factor in the optimal multiple regression model for change in TSH (R2=0.47). Plasma Se and iodine were negative and positive factors, respectively. There were also indications of changes in FT4, FT3 and the FT4:FT3 ratio consistent with a net inhibiting effect of As on FT4 to FT3 conversion. CONCLUSION: Ingestion of seafood rich in various organic As species was strongly associated with an increase of the TSH concentrations in plasma. Change in TSH was positively associated with total plasma As, but varied with the type of seafood ingested. These findings indicate that organic dietary As, apparently depending on chemical form, may influence thyroid hormones and function.

Treatment Algorithm for Patients with Non-arthritic Hip Pain, Suspect for an Intraarticular Pathology.

BACKGROUND: The amount of patients referred with longstanding, non-arthritic hip pain is increasing, as are the treatment options. Left untreated hip dysplasia, acetabular retroversion and femoroacetabular impingement (FAI) may lead to osteoarthritis (OA). Finding the right treatment option for the right patient can be challenging in patients with non-arthritic hip pain. PURPOSE: The purpose of this study was to categorize the radiographic findings seen in patients with longstanding hip pain, suspect for an intraarticular pathology, and provide a treatment algorithm allocating a specific treatment option for each clinical condition. MATERIAL AND METHODS: A review of the literature was performed using Public Medline searches of MeSH terms combined with synonyms for femoroacetabular impingement, acetabular retroversion, periacetabular osteotomy and hip arthroscopy. RESULTS: Radiographic findings associated with acetabular retroversion described in the literature were the crossover sign, the posterior wall sign and the ischial spine sign, while Wiberg's lateral center-edge angle (CE-angle) together with Leqeusne's acetabular index indicate hip dysplasia. A Tönnis index >2 indicates osteoarthritis, however unsatisfying results are documented following joint preserving surgery with a Tönnis index >1. Furthermore, ischial spine sign in combination with the posterior wall sign indicates total acetabular retroversion prone to periacetabular osteotomy in contrast to focal retroversion prone to hip arthroscopy. These findings were used creating a treatment algorithm for intraarticular pathologies in patients with longstanding hip pain. CONCLUSION: Based on the radiographic findings, the algorithm presented in this study can be a helpful tool in the decision-making for the treatment of patients with non-arthritic hip pain, suspect for intraarticular pathologies.

Urinary excretion of arsenicals following daily intake of various seafoods during a two weeks intervention.

The excretion pattern of arsenic (As) species after seafood intake varies widely depending on species ingested and individual handling. We have previously reported the 72 h urinary excretion of arsenicals following a single dose of seafood. Here, we report the excretion patterns in the same 37 subjects following 15 days daily consumption of either 150 g cod, salmon, blue mussels or potato (control), followed by a 72 h period with a low-As diet. In all seafood groups, total As (tAs) in plasma and urinary excretion of tAs, arsenobetaine (AB) and dimethylarsinate (DMA) increased significantly after the intervention. Confirming the single dose study AB and DMA excreted were apparently endogenously formed from other arsenicals ingested. Total tAs excretion was 1386, 763 and 303 µg in the cod, blue mussel and salmon groups, respectively; about twice the amounts after the single dose study indicating accumulation of arsenicals. In the cod group, rapid excretion after the single dose was associated with lower total As in blood and less accumulation after two weeks with seafood indicating lower accumulation. In the blue mussels group only, inorganic As (iAs) excretion increased significantly, whilst methylarsonate (MA) strongly increased, indicating a possible toxicological concern of repeated mussel consumption.

Experimental proof of adjustable single-knob ion beam emittance partitioning.

The performance of accelerators profits from phase-space tailoring by coupling of degrees of freedom. Previously applied techniques swap the emittances among the three degrees but the set of available emittances is fixed. In contrast to these emittance exchange scenarios, the emittance transfer scenario presented here allows for arbitrarily changing the set of emittances as long as the product of the emittances is preserved. This Letter is the first experimental demonstration of transverse emittance transfer along an ion beam line. The amount of transfer is chosen by setting just one single magnetic field value. The envelope functions (beta) and slopes (alpha) of the finally uncorrelated and repartitioned beam at the exit of the transfer line do not depend on the amount of transfer.

Major and minor arsenic compounds accounting for the total urinary excretion of arsenic following intake of blue mussels (Mytilus edulis): a controlled human study.

Blue mussels (Mytilus edulis) accumulate and biotransform arsenic (As) to a larger variety of arsenicals than most seafood. Eight volunteers ingested a test meal consisting of 150 g blue mussel (680 µg As), followed by 72 h with an identical, low As controlled diet and full urine sampling. We provide a complete speciation, with individual patterns, of urinary As excretion. Total As (tAs) urinary excretion was 328 ± 47 µg, whereof arsenobetaine (AB) and dimethylarsinate (DMA) accounted for 66% and 21%, respectively. Fifteen minor urinary arsenicals were quantified with inductively coupled plasma mass spectrometry (ICPMS) coupled to reverse-phase, anion and cation-exchange high performance liquid chromatography (HPLC). Thio-arsenicals and non-thio minor arsenicals (including inorganic As (iAs) and methylarsonate (MA)) contributed 10% and 7% of the total sum of species excretion, respectively, but there were large individual differences in the excretion patterns. Apparently, formation of thio-arsenicals was negatively correlated to AB formation and excretion, possibly indicating a metabolic interrelationship. The results may be of toxicological relevance since DMA and MA have been classified as possibly carcinogenic, and six of the excreted As species were thio-arsenicals which recently have been recognized as toxic, while iAs toxicity is well known.

Component-resolved in vitro diagnosis of carrot allergy in three different regions of Europe.

BACKGROUND: Carrot is a frequent cause of food allergy in Europe. The objective of this study was to evaluate a panel of carrot allergens for diagnosis of carrot allergy in Spain, Switzerland and Denmark. METHODS: Forty-nine carrot allergic patients, 71 pollen allergic but carrot-tolerant patients and 63 nonatopic controls were included. Serum IgE to carrot extract, recombinant carrot allergens (rDau c 1.0104; rDau c 1.0201; rDau c 4; the isoflavone reductase-like proteins rDau c IFR 1, rDau c IFR 2; the carrot cyclophilin rDau c Cyc) were analyzed by ImmunoCAP. RESULTS: The sensitivity of the carrot extract-based test was 82%. Use of the recombinant allergens increased the sensitivity to 90%. The Dau c 1 isoforms were major allergens for Swiss and Danish carrot allergic patients, the profilin rDau c 4 for the Spanish patients. The rDau c IFR 1 and rDau c IFR 2 were recognized by 6% and 20% of the carrot allergics, but did not contribute to a further increase of sensitivity. Among pollen allergic controls, 34% had IgE to carrot extract, 18% to each of rDau c 1.0104, rDau c 1.0201 and rDau c 4, 8% to rDau c IFR 1 and 7% to rDau c IFR 2. Sensitization to rDau c Cyc occurred in one carrot allergic patient and one nonatopic control. CONCLUSION: Component-resolved in vitro analyses revealed a significant difference in IgE sensitization pattern between geographical regions and in the prevalence of sensitization to carrot components between carrot allergic and carrot-tolerant but pollen sensitized patients.

Humans seem to produce arsenobetaine and dimethylarsinate after a bolus dose of seafood.

Seafood is the predominant food source of several organoarsenic compounds. Some seafood species, like crustaceans and seaweed, also contain inorganic arsenic (iAs), a well-known toxicant. It is unclear whether human biotransformation of ingested organoarsenicals from seafood result in formation of arsenicals of health concern. The present controlled dietary study examined the urinary excretion of arsenic compounds (total arsenic (tAs), iAs, AB (arsenobetaine), dimethylarsinate (DMA) and methylarsonate (MA)) following ingestion of a single test meal of seafood (cod, 780 µg tAs, farmed salmon, 290 µg tAs or blue mussel, 690 µg tAs or potato (control, 110 µg tAs)) in 38 volunteers. The amount of ingested tAs excreted via the urine within 0-72 h varied significantly among the groups: Cod, 74% (52-92%), salmon 56% (46-82%), blue mussel 49% (37-78%), control 45% (30-60%). The estimated total urinary excretion of AB was higher than the amount of ingested AB in the blue mussel group (112%) and also ingestion of cod seemed to result in more AB, indicating possible endogenous formation of AB from other organoarsenicals. Excretion of iAs was lower than ingested (13-22% of the ingested iAs was excreted in the different groups). Although the ingested amount of iAs+DMA+MA was low for all seafood groups (1.2-4.5% of tAs ingested), the urinary DMA excretion was high in the blue mussel and salmon groups, counting for 25% and 11% of the excreted tAs respectively. In conclusion our data indicate a possible formation of AB as a result of biotransformation of other organic arsenicals. The considerable amount of DMA excreted is probably not only due to methylation of ingested iAs, but due to biotransformation of organoarsenicals making it an inappropriate biomarker of iAs exposure in populations with a high seafood intake.

[The Innovation Office of the Paul-Ehrlich-Institut. Regulatory support during the scientific development of ATMP]. / Das Innovationsbüro am Paul-Ehrlich-Institut. Ein Angebot zur regulatorischen Begleitung der Entwicklung neuartiger Therapien.

In conformity with Regulation (EC) No. 1394/2007, advanced therapy medicinal products (ATMP) are now subject to the centralized marketing authorization procedure. This also applies to most medicinal products in regenerative medicine. ATMP that have been marketed in a member state by the end of 2008 must be centrally authorized by the end of 2012 at the latest. In exceptional cases, a national authorization is acceptable. Developers of these medicinal products are usually academic institutions or small- and medium-sized enterprises (SME). They focus on scientific aspects and usually have little experience with pharmaceutical law. The Innovation Office of the Paul-Ehrlich-Institut (PEI) is designed to support developers of medicinal products in the areas between research and development, on the one hand, and regulatory requirements, on the other. Its main role is supportive advice in the regulatory field with an emphasis on ATMP. For this purpose, the Innovation Office makes use of core competences from various experts at the PEI in order to provide a quality consulting service to those companies who are seeking advice as early as possible and hand in hand with the development process. The aim is to support the developer to identify the appropriate regulatory pathway and to provide advice for each individual medicinal product at its corresponding stage of development in order to develop a high-quality ATMP manufactured on the basis of positive nonclinical results and appropriate clinical studies that meet all the necessary requirements for the application of a marketing authorization.

Digested Ara h 1 has sensitizing capacity in Brown Norway rats.

BACKGROUND: Food allergies are a public health issue of growing concern, with peanuts in particular being associated with severe reactions. The peanut allergen, Ara h 1, belongs to the cupin plant food allergen family, which, unlike other structural families, appears to be broken down rapidly following gastrointestinal digestion. OBJECTIVE: Using Ara h 1 as a model allergen, the ability of digested protein to sensitize has been investigated. METHODS: Ara h 1 was purified from whole roasted peanuts. Intact Ara h 1 was digested in an in vitro model, simulating the human gastrointestinal digestion process. Digestion products were analysed for peptide sizes and their ability to aggregate. Brown Norway (BN) rats, used as an animal model, were immunized with purified intact Ara h 1 or the gastrointestinal digestion products thereof. The sensitizing capacity was evaluated by analyses of specific antibody (IgG1, IgG2a and IgE) responses and ability to trigger mediator release of rat basophilic leukaemia (RBL)-2H3 cells. RESULTS: The present study showed that Ara h 1 was broken down, resulting in peptide fragments of sizes<2.0 kDa, of which approximately 50% was in aggregated complexes of Mr up to 20 kDa. Ara h 1 digesta were shown to have sensitizing capacity in BN rats, being capable of inducing specific IgG and IgE antibodies. The IgE response was functional, having the capacity to induce specific degranulation of RBL cells. CONCLUSION: From this study, it can be concluded that lability of a food allergen to gastrointestinal digestion does not necessarily abrogate its allergenic sensitizing potential.

Experimental evidence of the 90 degrees stop band in the GSI UNILAC.

In a particle accelerator with a periodic structure beam space charge force may excite resonant beam emittance growth if the particle's transverse phase advance approaches 90 degrees . A recent simulation study with the PARMILA code [D. Jeon, Phys. Rev. ST Accel. Beams 12, 054204 (2009)]10.1103/PhysRevSTAB.12.054204 has shown the feasibility of measuring the stop band of this fourth order resonance in the GSI Universal Linear Accelerator UNILAC and proposed its experimental verification, which is reported here. Measurements of transverse phase space distributions behind a periodically focusing structure reveal a fourfold symmetry characteristic of fourth order resonances as well as a resonance stop band above sigma_{0}=90 degrees per focusing cell. These experimental findings agree with results from three different beam dynamics simulation codes, i.e., DYNAMION, PARMILA, and TRACEWIN.

Experimental evidence of space charge driven emittance coupling in high intensity linear accelerators.

In high intensity linacs emittance exchange driven by space charge coupling may lead to the well-known "equipartitioning" phenomenon if the stop band at sigma(parallel) = sigma(perpendicular) is crossed at sufficiently slow rate. This Letter is the first experimental evidence of this phenomenon in a high intensity linear accelerator, here the UNILAC at GSI. Measurements of emittances at the entrance and exit of one drift tube linac tank comprising 15 lattice cells are taken for a set of transverse and longitudinal tunes. The onset of exchange on the stop band of previously derived "stability charts" confirms theoretical predictions. The measured transverse emittance growth also compares well with results from the beam dynamics simulation codes DYNAMION and TRACEWIN.

Differences in trabecular bone texture between knees with and without radiographic osteoarthritis detected by fractal methods.

OBJECTIVE: To develop an accurate method for quantifying differences in the trabecular structure in the tibial bone between subjects with and without knee osteoarthritis (OA). METHODS: Standard knee radiographs were taken from 26 subjects (seven women) with meniscectomy and radiographic OA Kellgren & Lawrence grade 2 or worse in the medial compartment. Each case knee was individually matched by sex, age, body mass index and medial or lateral compartment with a control knee. A newly developed augmented Hurst orientation transform (HOT) method was used to calculate texture parameters for regions selected in X-ray images of non-OA and OA tibial bones. This method produces a mean value of fractal dimensions (FD MEAN), FDs in the vertical (FDV) and horizontal (FDH) directions and along a direction of the roughest part of the tibial bone (FDSta), fractal signatures and a texture aspect ratio (Str). The ratio determines a degree of the bone texture anisotropy. Reproducibility was calculated using an intraclass correlation coefficient (ICC). Comparisons between cases and controls were made with paired t tests. The performance of the HOT method was evaluated against a benchmark fractal signature analysis (FSA) method. RESULTS: Compared with controls, trabecular bone in OA knees showed significantly lower FD MEAN, FDV, FDH and FDSta and higher Str at trabecular image sizes 0.2-1.1mm (P<0.05, HOT). The reproducibility of all parameters was very good (ICC>0.8). In the medial compartment, fractal signatures calculated for OA horizontal and vertical trabeculae were significantly lower at sizes 0.3-0.55 mm (P<0.05, HOT) and 0.3-0.65 mm (P<0.001, FSA). In the lateral compartment, FDs calculated for OA trabeculae were lower than controls (horizontal: 0.3-0.55 mm (P<0.05, HOT) and 0.3-0.65 mm (P<0.001, FSA); vertical: 0.3-0.4mm (P<0.05, HOT) and 0.3-0.35 mm (P<0.001, FSA). CONCLUSION: The augmented HOT method produces fractal signatures that are comparable to those obtained from the benchmark FSA method. The HOT method provides a more detailed description of OA changes in bone anisotropy than the FSA method. This includes a degree of bone anisotropy measured using data from all possible directions and a texture roughness calculated for the roughest part of the bone. It appears that the augmented HOT method is well suited to quantify OA changes in the tibial bone structure.

Validity and reliability of functional performance tests in meniscectomized patients with or without knee osteoarthritis.

AIMS: Reduced functional performance and muscular dysfunction after knee injury and in knee osteoarthritis (OA) is suggested to be a factor in OA development. Validated functional performance tests applicable in the clinic and large-scale studies are lacking. The aim was to study the reliability and validity of 10 functional performance tests. METHODS: Two hundred and eighty-five subjects, 15-22 years post-meniscectomy, performed 10 functional performance tests. The mean age was 54 years (SD+/-11.2) and 79% were men; 52% had radiographic OA, and 48% were categorized as symptomatic. The tests were evaluated for test-retest reliability, discriminative ability (younger vs older age, men vs women, symptom-free vs symptomatic) and floor and ceiling effects. RESULTS: Two of the 10 tests, maximum number of knee bendings in 30 s and one-leg hop for distance, had good test-retest reliability (ICC 0.92, 95% CI 0.86-0.96 and 0.93, 95% CI 0.87-0.97) and were able to discriminate with regard to age, gender and symptoms, and had acceptable floor effects (9% and 3%, respectively). CONCLUSION: This study suggests the use of two functional performance tests: knee bendings/30 s and one-leg hop for distance, easy to use for evaluation of interventions due to knee injury and knee OA and when attaining long-term data of natural disease history.

Heart murmurs recorded by a sensor based electronic stethoscope and e-mailed for remote assessment.

BACKGROUND: Heart murmurs are common in children, and they are often referred to a specialist for examination. A clinically innocent murmur does not need further investigation. The referral area of the University Hospital is large and sparsely populated. A new service for remote auscultation (telemedicine) of heart murmurs in children was established where heart sounds and short texts were sent as an attachment to e-mails. AIM: To assess the clinical quality of this method. METHODS: Heart sounds from 47 patients with no murmur (n = 7), with innocent murmurs (n = 20), or with pathological murmurs (n = 20) were recorded using a sensor based stethoscope and e-mailed to a remote computer. The sounds were repeated, giving 100 cases that were randomly distributed on a compact disc. Four cardiologists assessed and categorised the cases as having "no murmur", "innocent murmur", or "pathological murmur", recorded the assessment time per case, their degree of certainty, and whether they recommended referral. RESULTS: On average, 2.1 minutes were spent on each case. The mean sensitivity and specificity were 89.7% and 98.2% respectively, and the inter-observer and intra-observer variabilities were low (kappa 0.81 and 0.87), respectively. A total of 93.4% of cases with a pathological murmur and 12.6% of cases with an innocent murmur were recommended for referral. CONCLUSION: Telemedical referral of patients with heart murmurs for remote assessment by a cardiologist is safe and saves time. Skilled auscultation is adequate to detect patients with innocent murmurs.

[Cases of measles in Denmark are caused by reintroduction of virus from abroad]. / Maeslingetilfaelde i Danmark skyldes gentagne introduktioner af virus fra udlandet.

Measles vaccination was implemented in the child vaccination programme in Denmark in 1987 and produced a rapid decline in the incidence. Few cases were recorded annually until 1999. The measles virus isolated in Denmark during 1997-1998 was compared by partial sequencing of the haemagglutinin-coding region with Danish strains from the prevaccination era collected in 1965-1983, as well as with representatives of globally circulating strains of today. The dissimilarity of the prevaccination era strains identified in Denmark in 1997-1998 along with the similarity of these five strains with globally circulating strains at present, substantiate the conclusion that there is no persistent circulation of the measles virus in Denmark.

High-nuclearity close-packed palladium-nickel carbonyl phosphine clusters: heteropalladium.

[Pd(16)Ni(4)(CO)(22)(PPh(3))(4)](2)(-) (1) and [Pd(33)Ni(9)(CO)(41)(PPh(3))(6)](4)(-) (2) were obtained as the two major products from the reduction of PdCl(2)(PPh(3))(2) with [Ni(6)(CO)(12)](2)(-). Their crystal structures as [PPh(4)](+) salts were unambiguously determined from CCD X-ray crystallographic analyses; the resulting stoichiometries were ascertained from elemental analyses. Infrared, multinuclear (1)H, (31)P[(1)H] NMR, UV-vis, CV, variable-temperature magnetic susceptibility, and ESI FT/ICR mass spectrometric measurements were performed. The Pd(16)Ni(4) core of 1 ideally conforms to a ccp nu(3) tetrahedron of pseudo-T(d)() (4 3m) symmetry. Its geometry normal to each tetrahedral Pd(7)Ni(3) face (i.e., along each of the four 3-fold axes) may be viewed as a four-layer stacking of 20 metal atoms in a ccp [a(Ni(1)) b(Pd(3)) c(Pd(6)) a(Pd(7)Ni(3))] sequence. A comparative analysis of the different ligand connectivities about the analogous metal-core geometries in 1 and the previously reported [Os(20)(CO)(40)](2)(-) has stereochemical implications pertaining to the different possible modes of carbon monoxide attachment to ccp metal(111) surfaces. The unique geometry of the Pd(33)Ni(9) core of 2, which has pseudo-D(3)(h)() (6 2m) symmetry, consists of five equilateral triangular layers that are stacked in a hcp [a(Pd(7)Ni(3)) b(Pd(6)) a(Pd(7)Ni(3)) b(Pd(6)) a(Pd(7)Ni(3))] sequence. Variable-temperature magnetic susceptibility measurements indicated both 1 and 2 to be diamagnetic over the entire temperature range from 5.0 to 300 K. Neutral Pd(12)(CO)(12)(PPh(3))(6) (3) and [Pd(29)(CO)(28)(PPh(3))(7)](2)(-) (4) as the [PPh(4)](+) salt were obtained as minor decomposition products from protonation reactions of 1 and 2, respectively, with acetic acid. Compound 3 of pseudo-D(3)(d)() (3 2/m) symmetry represents the second highly deformed hexacapped octahedral member of the previously established homopalladium family of clusters containing uncapped, monocapped, bicapped, and tetracapped Pd(6) octahedra. The unprecedented centered 28-atom polyhedron for the Pd(29) core of 4 of pseudo-C(3)(v)() (3m) symmetry may be described as a four-layer stacking of 29 metal atoms in a mixed hcp/ccp [a(Pd(1)) b(Pd(3)) a(Pd(10)) c(Pd(15))] sequence.

Determination of iodine in seafood by inductively coupled plasma/mass spectrometry.

A method was developed for determination of total iodine content in different standard reference materials (SRMs) and seafood products by inductively coupled plasma/mass spectrometry (ICP/MS). If iodine is present as iodide and nitric acid is used in the wet digestion system, the observed signal is not stable when iodine is measured by ICP/MS at m/z 127. To stabilize the iodine signal, 3% ammonia solution (1 + 1, v/v) was added to the digest. The limit of quantitation of the method, defined as 6 times the standard deviation in the blank solution (n = 20) was estimated to be 15 mg/kg (using 0.2 g dry mass and a dilution factor of 50). The precision, expressed as repeatability of the iodine concentration, varied between 3.2 and 12% in SRMs, with concentrations of 4.70-0.17 mg/kg dry matter. The described method was compared with a method using tetramethylammonium hydroxide extraction. Both methods showed good precision and trueness by analyses of SRMs. The 2 methods were used to determine iodine in seafood from the Barents Sea, the Norwegian Sea, and the North Sea. The results showed great variation between different fish species as well as between individuals within a species. The lowest values of iodine were recorded in muscle of ling (Molva molva) with a mean of 0.07 mg/kg fresh weight and a variation between 0.03 and 0.11 mg/kg fresh weight. The highest values were found in cod (Gadus morhua) from the Barents Sea, with a mean of 2.5 mg/kg and a variation between 0.7 and 12.7 mg/kg fresh weight.