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Biomedical subjects

C Rappe

Publications and source records attributed to C Rappe.

At least 37 records · Page 2Linked to original sources
PubMed1996

[Polychlorinated naphthalenes in Harbour porpoises Phocoena phocoena].

Concentration and composition of chloronaphthalenes (PCNs) were determined in blubber of two male and two female porpoises from the Gulf of Gdańsk. Porpoises examined died in the fishing nets in 1992. Polychlorinated naphthalenes were determined using capillary gas chromatography and high resolution mass spectrometry (HRGC/HRMS) after nondestructive cleanup with polyethylene membrane, and pre-separation of planar compounds on carbon HPLC column. 28 peaks from chloronaphthalenes were identified and quantified on a chromatogram. Concentration of total PCNs in blubber of male porpoises were 1.7-2.4 ng/glipid weight, and of female 2.0-2.4 ng/g. Among of the PCN congeners found 1,2,3,4,6,7-/1,2,3,5,6,7-hexachloronaphthalene (PCN nr 66/67) and 1,2,4,6-/1,2,5,7-tetrachloronaphthalene (PCN nr 3/34/37) were dominating compounds, followed by 1,4,6,7-tetrachloronaphthalene (PCN nr 47), 1,2,3,5-/1,3,5,8-tetrachloronaphthalene (PCN nr 28/43) and 1,2,3,5,7-/1,2,4,6,7-pentachloronaphthalene (PCN nr 52/60), and others were minor contributors.

Adipose Tissue↗
PubMed1996

[Dioxins and furans in edible species of fish from the Gulf of Gdańsk].

The levels of PCDDs and PCDFs in samples of lamprey, perch, herring, cod, flounder, round goby, eelpout and pikeperch caught in the Gulf of Gdańsk were determined by HRGC/HRMS. The results are expressed as TCDD equivalents, calculated according to international (I-TEQs), nordic (N-TEQs) models. The levels (pg TEQs/g wet weight) were from 0.263 in lamprey to 6.047 in herring (I-TEQs). Except of herring nearly all fish species sampled contained PCDDs and PCDFs in concentration below 1 pg TEQs/g wet wt, and only for pikeperch it was 1.025 pg S-TEQs/g.

Adipose Tissue↗
PubMed1995

Supercritical fluid extraction of PCBs from human adipose tissue for HRGC/LRMS analysis.

Supercritical fluid extraction (SFE) of 36 PCBs from human adipose is presented. Selective extraction of the PCBs is achieved using supercritical CO2 with a density of 0.9 g/ml (281 bar) at 40 degrees C and with AlOx as a fat retainer. Compared to the traditional liquid extraction method followed by further sample clean up, SFE is not only faster (2 hours compared to three days) but also utilises lower amounts of organic solvents (4 ml compared to over 500 ml). The recoveries of 7 added 13C labelled PCBs are 83-106%. The repeatability in the analysis of 36 PCBs in 6 identical samples is excellent, with an average R.S.D. of less than 10%.

Adipose Tissue↗
PubMed1995

Absorption of polychlorinated biphenyls, dibenzo-p-dioxins and dibenzofurans by breast-fed infants.

The absorption of polychlorinated biphenyls, dibenzo-p-dioxins and dibenzofurans was studied in four breast-fed infants. The absorption was measured by comparing the estimated total intake and the excretion in faeces, during 48 hours, at three different time points; 1, 2 and 3 months post parta. The levels of the analysed compounds in the human milk are typical for Sweden, i.e approximately 20 ppt toxic equivalents for the dibenzo-p-dioxins and dibenzofurans and for the polychlorinated biphenyls approximately 16 ppt toxic equivalents. For most of the congeners the absorption is found to be over 95%. Higher excretion is noticed for heptachlorinated and octachlorinated dioxins.

Absorption↗
PubMed1995

Adipose tissue concentrations of dioxins and dibenzofurans in patients with malignant lymphoproliferative diseases and in patients without a malignant disease.

Concentrations of dioxins (PCDD) and dibenzofurans (PCDF) were analysed in adipose tissue from seven patients with malignant lymphoproliferative diseases and 12 surgical patients without a malignant disease. All cases in the first group had reported potential exposure to PCDD and PCDF. Of the analysed congeners significantly higher concentrations of 1,2,3,7,8-pentachlorodioxin, 1,2,3,6,7,8-hexachlorodioxin, and 2,3,4,7,8-pentachlorodibenzofuran were found in the cases with lymphoproliferative diseases compared with the patients in the other group. Higher mean concentration of 2,3,7,8-TCDD was also found in the first group but not significantly so. Toxic equivalents of PCDD and PCDF were significantly higher in the first group (mean 64.7 pg/g, range 19.9-187) than in the second group (mean 29.7 pg/g, range 12.9-53.4). Even if the cases with lymphoproliferative diseases in this case series were potentially exposed to PCDD/PCDF in contrast to the other group, the observed differences may be of may be of interest in relation to the aetiology of these malignancies. Immunosuppression increases the risk for malignant lymphoproliferative diseases, and PCDD/PCDF have established immunotoxic properties.

Adipose Tissue↗
PubMed1995

Occupational exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans in a magnesium production plant.

OBJECTIVES: The production of magnesium is a well known source of both aliphatic and aromatic chlorinated compounds, among others the polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The aim of this study was to establish whether increased concentrations of PCDDs and PCDFs could be found in the blood of workers in a magnesium plant. METHODS: Blood plasma from 10 workers, employed at a magnesium plant for 10 to 36 years, and from a control group consisting of nine people who had no direct contact with the production were studied. Isomer specific analyses of PCDDs and PCDFs by means of high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) techniques were performed. RESULTS: A significant increase was found in the concentrations of some of the congeners, mainly PCDFs, in the workers compared with the control group. Octachlorodibenzofuran (OCDF) is the congener that most strongly correlates with occupational exposure in the magnesium plant. Low concentrations of 1,2,3,4,6,8,9-heptachlorodibenzofuran were found in seven of the workers. Such isomers--that is, not 2,3,7,8-substituted--are rarely found in human samples. CONCLUSION: Due to the long biological half lives and lipid solubility of PCDDs and PCDFs, blood analyses may serve as an index of past cumulative occupational exposure and a means of assessing a person's exposure situation.

Benzofurans↗
PubMed1994

A toxic equivalency factor scale for polychlorinated dibenzofurans.

The ethoxyresorufin O-deethylase (EROD) induction of 20 polychlorinated dibenzofurans (PCDFs) was examined in the H4IIE rat hepatoma cell bioassay. The selection of the compounds tested was based on a multivariate chemical characterization laying the groundwork for covering the whole chemical series of PCDFs. The EROD induction potency was found to vary in ED50 values from 25 to 100,000,000 pg/mg, i.e., nearly seven orders of magnitude. The response of the bioassay was calibrated against the 2,3,7,8-tetrachlorodibenzo-p-dioxin, enabling the corresponding toxic equivalency factors (TEFs) to be calculated. In order to establish a quantitative structure-activity relationship (QSAR) for the TEF values, 37 physicochemical descriptor variables were used to chemically characterize the 87 tetra- to octachlorinated PCDFs. Using partial least-squares modeling on a training set of 10 congeners, a QSAR model with sound predictive power was obtained. The QSAR model was validated with a validation set of additional 10 congeners. The predicted TEFs indicate that a large number of congeners are potent EROD inducers.

Animals↗
PubMed1992

World Health Organization international intercalibration study on dioxins and furans in human milk and blood.

Under the sponsorship of the World Health Organization (WHO), an interlaboratory calibration on the analysis of PCDD/PCDFs in human milk and blood was carried out which included 19 laboratories from 14 countries. The study design involved the analysis of three samples of each matrix in triplicate. Selected samples were spiked with native standards of certain 2,3,7,8-substituted congeners at concentrations known only to WHO staff. The study design resulted in approximately 4000 individual pieces of PCDD/PCDF data generated by a variety of analytical methods, at various concentrations, and by laboratories of widely different experience. This was, by considerable margin, the largest study which allowed for the direct comparison of laboratory and method performance. The results of statistical analysis of this data base addresses the effect on data quality of clean up methods, instrumental methods, analyte concentration, laboratory QA programs, and laboratory experience. The study has shown that the laboratory is the single most important determinant of data precision and accuracy. The method of analyte enrichment (sample clean up), analyte measurement [gas chromatography/mass spectrometry (GC/MS) protocol], and analyte concentration have weaker correlations with data quality.

Chromatography, Gas↗
PubMed1992

Impact of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls on human and environmental health, with special emphasis on application of the toxic equivalency factor concept.

A scientific evaluation was made of the mechanisms of action of polychlorinated dibenzo-p-dioxins, dibenzofurans and biphenyls. Distinction is made between the aryl-hydrocarbon (Ah) receptor-mediated and non-Ah receptor-mediated toxic responses. Special attention is paid to the applicability of the toxic equivalency factor (TEF) concept.

Animals↗
PubMed1991

Exposure to dioxins and dibenzofurans through the consumption of fish.

BACKGROUND: In some regions, including the Baltic Sea, fatty fish such as salmon and herring contain high levels of polychlorinated dibenzodioxins and dibenzofurans. We investigated human exposure to these potentially toxic substances in relation to the consumption of fish from the Baltic Sea. METHODS: Plasma levels of 10 different dibenzofurans and 7 dioxins were analyzed in three groups of Swedish men: one group with a high intake of fish (fish eaten almost daily; n = 11), one with a moderate intake of fish (about once per week; n = 9), and one with no consumption of fish (usually because of allergy; n = 9). RESULTS: Plasma levels of several of the compounds we measured were higher in the men with a high intake of fish than in those who consumed moderate amounts, and the levels were higher in those who ate moderate amounts of fish than in those who ate none. The median amounts of the most toxic dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin) were 8.0 pg per gram of plasma lipid (range, 2.0 to 13) in the high-intake group, 2.6 pg per gram (range, 1.2 to 4.2) in the moderate-intake group, and 1.8 pg per gram (range, 1.0 to 2.5) in the nonconsumers (P = 0.001 and 0.02, respectively). There were consistent and statistically significant associations between the reported amount of fish eaten and the plasma levels of several of the dibenzofurans and dioxins. CONCLUSIONS: Contaminated fish such as those from the Baltic Sea are an important source of exposure to polychlorinated dibenzofurans and dibenzodioxins in persons who eat fish regularly. However, the clinical consequences of such exposure remain uncertain.

Adult↗
PubMed1991

Chloracne caused by ingestion of olive oil contaminated with PCDDs and PCDFs.

1. All members of a Spanish family (father, mother and six children) developed chloracne. 2. The causative agent was found to be the family's stock of olive oil, which had become contaminated with polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), pentachlorophenol, and hexachlorobenzene. 3. The more highly chlorinated PCDDs, in particular octachlorodibenzo-p-dioxin, were the predominant congeners in the oil. 4. Three members of the family exhibited either an overt or a sub-clinical disturbance of kidney function. The father also had a chronic respiratory problem. These changes could not be unequivocally attributed to the PCDDs. 5. Experimental toxicity of the oil was limited to the development of an hepatic porphyria in mice. 6. A serum sample, taken 5 years after consumption of the oil ceased, contained high levels of the PCDDs and PCDFs. Extrapolation back to ingested dose was used to validate dosage estimates. 7. The use of toxicity equivalence factors (TEFs) provided estimates of cumulative dosage to produce chloracne as 0.13-0.31 micrograms 2378-TCDD kg-1 (using EPA TEFs) or 6.7-16 micrograms 2378-TCDD kg-1 (using Nordic/NATO TEFs). 8. This is the first incident in which human toxicity is related primarily to ingestion of PCDDs and for which estimates of dosage can be made.

Acne Vulgaris↗
PubMed1990

Environmentally stable chlorinated contaminants from the pulp and paper industry.

Toxic polychlorinated dioxins and dibenzofurans have been identified in effluents and products from pulp and paper mills using chlorine bleaching. The amounts and levels depend on the bleaching technique used and the product quality. The same compounds have also been identified in sediment samples and aquatic organisms collected in the vicinity of pulp mills. The highest levels were found in hepatopancreas from crustaceans. Much higher levels of alkyl-substituted polychlorodibenzofurans have been found in sediment and sludge samples.

Animals↗
PubMed1989

Residues of polychlorinated-dibenzodioxins, -dibenzofurans and -biphenyls in human milk samples collected in a continental town in Croatia, Yugoslavia.

The levels of several polychlorinated-dibenzodioxins (PCDDs), polychlorinated-dibenzofurans (PCDFs) and total polychlorinated-biphenyls (PCBs) were determined in pooled human milk samples. The samples were collected in a continental town of Croatia, Yugoslavia, during the years 1981/82 and 1985. The concentrations of seven PCDDs and nine PCDFs were within the range less than 0.2-116 ng/kg milk fat; the total PCBs were 0.47 and 0.32 mg/kg milk fat. The levels determined were about the same as those reported for the general population in other countries.

Benzofurans↗
PubMed1988

Dioxins and dibenzofurans in blood and adipose tissue of Agent Orange-exposed Vietnam veterans and matched controls.

Vietnam veterans who were heavily exposed to Agent Orange exceeded matched control subjects in both blood and adipose tissue levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) but not in the levels of the 12 other 2,3,7,8-substituted dioxins and dibenzofurans that were detected. Since only TCDD among these compounds was present in Agent Orange but all are present in the population of the industrialized world, it is likely that the elevated TCDD levels arose from wartime exposure. The high correlation (r = +.89) of blood with adipose tissue level suggests that there may be a mobile equilibrium between them and that blood measurement could replace adipose tissue measurement of TCDD levels, making the collection of human data less invasive.

2,4,5-Trichlorophenoxyacetic Acid↗
PubMed1986

Short-term mortality and cancer incidence in capacitor manufacturing workers exposed to polychlorinated biphenyls (PCBs).

A cohort study of 142 male Swedish capacitor manufacturing workers was performed. PCB had been used as a dielectricum in power capacitors between 1960 and 1978. Mortality was investigated for the period 1965 to 1982 and cancer incidence from 1965 to 1980. Twenty-one deaths and seven cancers were observed, which was in agreement with the anticipated numbers calculated from national statistics. One person had developed two rare tumors, a slow growing mesenchymal tumor (desmoid) and a malignant lymphoma. The results cannot rule out the possibility of a carcinogenic risk from PCB exposure because of the small size of the cohort and relatively brief follow-up period, but they do not indicate any excess mortality or cancer incidence in this factory so far.

Adult↗