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Twenty-seven black guillemot eggs and 39 livers were analysed for polychlorinated biphenyls (PCBs), chlorinated pesticides including chlordane-related compounds and toxaphene, and polybrominated diphenylethers (PBDEs). The samples were collected at Qeqertarsuaq (Godhavn, West Greenland) and Ittoqqortoormiit (Scoresbysund, East Greenland). The concentrations of halogenated organic compounds in samples from East Greenland were somewhat higher than the corresponding concentrations from West Greenland. Differences in compound patterns were found between West and East Greenland, with higher percentages of the heavier PCB molecules, p,p(')-DDE and alpha-HCH in the samples from Ittoqqortoormiit. Similarly, different levels and different compositions were observed for eggs and livers. The eggs had generally higher concentrations of all compounds as well as higher percentages of CHB-50, CHB-62 and alpha-HCH than liver samples from the same area. Dividing the liver samples into age groups revealed increasing concentrations with age.

In the United States, it is necessary to analyze for toxaphene using approved, validated methods acceptable to the regulatory agencies. As a result of an interlaboratory study and technical exchanges among the US EPA Region IV (EPA), the State of Georgia Environmental Protection Division (EPD), and Hercules Incorporated, guidelines for the application of SW-846 Method 8080 were developed. Results of analyses for sludge, soil, and water samples agreed within a percent relative standard deviation (% RSD) range of 6.9-20%. Through continued technical interchanges, guidance for the application of SW-846 Method 8081 has been developed. The results of analyses of fourteen split samples of soil and sediment produced a percent relative standard deviation that ranged from 1.6% to 127%, with an average of 38%. When two unusually divergent results were removed from consideration, the average % RSD reduced to 26%. The results of analyses of split samples show agreement between the EPA laboratory and a Hercules contract laboratory. Therefore, the guidance has achieved its purpose of producing agreement among data from different laboratories so that data reviewers may have assurance that the analytical method has been applied correctly and consistently for the determination of toxaphene in environmental samples.

Organochlorines (DDT, toxaphene, PCBs, chlordane, HCHs, dieldrin) were quantified in the blubber of eleven fur seals of the species Arctocephalus pusillus pusillus. The sample clean-up included microwave-assisted extraction (MAE), gel-permeation chromatography (GPC), adsorption chromatography on silica gel and quantitation with GC/ECD. Compounds of technical toxaphene (CTTs) were determined after separation from the PCBs. Highest levels arose for p , p ′-DDE (7–1000 μg/kg). A so far unknown compound labelled Q1 caused the second most abundant peak in the samples. Q1 was identified as a heptachloro compound by GC/MS in the electron capture negative ionisation and electron impact ionisation mode. Levels of Q1 were estimated relative to the ECD response factor of trans -nonachlor. These estimated Q1 levels ranged from 27 to 351 μg/kg being in the range or higher than the levels of PCBs (6–697 μg/kg), toxaphene (10–97 μg/kg), chlordane (3–159 μg/kg), and dieldrin (4–36 μg/kg). One sample which showed significantly higher DDT and PCB levels (but not toxaphene, dieldrin, Q1, and chlordane) than the others is most likely migrated from an area higher polluted with DDT and PCBs. Another one showed very low levels which were not explained. Except these samples, the levels determined in the blubber were among the lower levels reported for this kind of tissue. The data also confirmed that the organochlorine levels in Africa are varying from region to region, and that there is still a need for further research.

Enantioseparations of 26 chiral organochlorine compounds (α-hexachlorocyclohexane, toxaphene, chlordane, atropisomeric polychlorinated biphenyls) were studied with GC–electron-capture detection. The chiral stationary phases (CSPs) consisted of 35% heptakis (6 -O-tert. -butyldimethylsilyl-2,3-di -O- methyl)-β-cyclodextrin (β-TBDM) diluted in OV1701. One CSP was made of pure β-TBDM (purity>99%) while the other was randomly silylated β-TBDM. High-temperature gas chromatography showed that this CSP contained five products in almost equal amounts. Both β-TBDM columns were installed in parallel in the same GC system. On the randomly silylated β-TBDM, aromatic compounds had shorter and aliphatic compounds had longer retention times than on the purified β-TBDM. The randomly silylated β-TBDM resolved the enantiomers of 24 compounds (16 of them were baseline separated) and the purified β-TBDM only six (four of them were baseline separated). Thus, the purification of β-TBDM decreased the efficiency of the chiral resolution of organochlorine compounds on β-TBDM. The results clearly demonstrate that the randomly silylated β-TBDM contains one or more side products more suitable for the enantioseparation of organochlorine compounds than the purified β-TBDM.

The HRGC determination of toxaphene residues in environmental samples is often difficult because of different degradation rates and accumulation behavior of individual toxaphene components. Therefore, isolated environmentally relevant chlorinated bornanes are used as standards. During the last years, single components as well as different combinations of them have been tested for their suitability for HRGC-HRMS-ECNI quantification. In this study, Parlar #26, Parlar #40, Parlar #41, Parlar #44, Parlar #50, and Parlar #62 have been used. The results show the sum of these six components to be at least 80–85% of toxaphene in fish oils.

Capillaries based on tert.-butyldimethylsilylated β-cyclodextrin (TBDMS-CD) diluted in OV-1701 have gained increasing interest for the enantioselective separation of lipophilic polychlorinated pesticides. A modified test according to Schurig for chiral stationary phases was not suitable for testing TBDMS-CD due the lack of sufficiently lipophilic compounds. A test mixture was developed containing the chiral polychlorinated pesticides α-hexachlorocyclohexane, cis- and trans-chlordane, heptachlor-exo-epoxide and 2-exo,3-endo,5-exo,6-endo,8,8,9,10,10-nonachloro-bornane. They are especially sensitive to changes in the enantioselective properties of TBDMS-CD which is also frequently used for these compounds. Cis- and trans-chlordane with different enantiomer ratios facilitate the detection of changes of the enantiomer elution order. Test results of laboratory-made and commercial capillaries are presented showing the usefulness of the test to detect differences in the enantioselective behaviour such as changes in the elution order of enantiomers. Electrospray MS was used for the characterisation of TBDMS-CD. The analysed batches contained homologues with 7–10 TBDMS groups in a mixture of variable composition. This is assumed to be the reason for the observed differences.

An abundant heptachloro bornane in cod livers, TOX7, has been isolated by repeated high performance liquid chromatography. Its identity was confirmed by GC/MS in the EI and ECNI mode. Larger quantities of TOX7 were isolated from Melipax® and its structure was elucidated by EI mass spectrometry and 1 H-NMR measurements as 2-exo, 3-endo, 5-exo, 9, 9, 10, 10-heptachlorobornane. The structural similarity of TOX7 with TOX8 as well as Parlar #41 were discussed.

A summary is given of research conducted by our laboratory since 1991 on the dispersion and pathways of persistent organochlorines (POCs) to remote regions of the Northern North Atlantic. This review includes data not previously published and an overall interpretation of our results. Levels of polychlorinated dibenzo-p-dioxins, dibenzofurans, biphenyls and pesticides in marine mammals and sediments from these areas are presented and discussed. Special attention is given to the levels of polychlorinated bornanes (toxaphene), to date the most heavily used insecticide worldwide. Finally, temporal trends are presented.

In the literature the nomenclature used for chlorinated substances with bornane and camphene skeletons is nonuniform. In order to prevent misunderstandings the current WPAC rules are presented and applied to known Toxaphene components.

A systematic code for a comprehensive numbering of toxaphene congeners on the basis of IUPAC rules has been developed. All chlorinated bornanes were characterized with a descriptor consisting of up to six letters and numbers. Each descriptor presents both enantiomers in the case of chiral compounds. Furthermore, chlorinated bornane congeners with a known structure are presented with both IUPAC nomenclature and the new systematic code. A computer program listing all the congener numbers is available from the authors.

Residues of DDT and its metabolites, hexachlorocyclohexanes (HCHs), chlordane, toxaphene, polychlorinated biphenyls (PCBs), and hexachlorobenzene (HCB) were determined by GC ECD and GC MS in the blubber of a seal (Phoca caspica) from the coast of Iran on the Caspian Sea. The organochlorine pattern was dominated by DDT and its metabolites while PCBs (65 PCB congeners including non-ortho PCBs were quantified) only played a minor role. The high content of β-HCH determined by GC ECD and confirmed by GC MS was interpreted to be caused by local sources. On the other hand, residues of chlordane compounds were correlated to atmospheric long-range transport.

Theoretical aspects of polychlorinated bornanes—the major part of technical toxaphene—and the composition of technical toxaphene were compared with results derived from multidimensional gas chromatograph analysis of the multicomponent mixture. Stereochemical aspects and a common nomenclature for polychlorinated bornanes are presented. Considerations of the persistence of some toxaphene compounds are made.

There are still wide differences in the number of congeners estimated and measured for the insecticidal toxaphene mixture. Purely theoretical considerations are not very helpful, since compounds with the most unlikely Cl substitution are counted and included just like those that are known and already isolated. Counting the substances with the aid of a high resolution GC-MS system can, aside from the errors that are involved, not provide any structural information except whether the compounds are saturated or unsaturated. For this reason it is not known what chlorine substitutions are possible for the bornanes and accordingly which are present in the mixture. Recent results on the isolation and structural elucidation of 27 congeners form the basis for postulates made in this contribution concerning the structure of chlorinated bornanes and a calculation of the number of significant toxaphene components. This allows a concrete picture to be formed of this class of substance.

The HRGC determination of Toxaphene R residues in fish tissues is often difficult because of the differing accumulation behaviour and decomposition rates of the individual Toxaphene compounds. This problem can satisfactorily be overcome by using purely isolated environmentally relevant chlorinated bornane derivatives (Parlar Nr. 26, 32, 50, 42, 69). The method is highly selective for measuring Toxaphene residues in complex marine organism matrices.

Concentrations of toxaphene (polychlorinated monoterpenes, chlorobornanes) were determined in human milk samples from Nicaragua and in fish from the North Sea. Relatively high toxaphene levels were found in the Nicaraguan human milk samples. The lack of correlation between the number of children of the mothers and toxaphene levels in their milk suggests a compensation of the elimination of toxaphene by a regularly high toxaphene intake. The increasing trend of toxaphene concentrations in North Sea fish sampled further away from the European coast suggests an aerial transport of toxaphene from the American continent to Europe.

In order to interpret present and predict future environmental concentrations of persistent organochlorine pesticides in remote regions information on historical and future trends in emissions and use of these compounds on a global scale is required. Through contact with international agencies, literature surveys and other means information on registration status, trends in regional use/emissions, mode and time of application as well as representative soil concentrations of ten pesticides are been compiled. Data of global toxaphene usage were collected for more than 50 countries around world. The accounted for cumulative global toxaphene usage were estimated to be 450,000 tonnes, the interpolated usage from 1950 to 1993 were 1,330,000 tonnes and from 1970 to 1993 were 670,000 tonnes. Toxaphene is still being in applied eg. in former Soviet Union and in Mexico. International cooperation and improved record keeping by governments are required to improve the estimates.

Pooled samples of homogenized Guillemot eggs from 1974, 1978, 1982 and 1987 and ten individual eggs for each of the two years, 1976 and 1989 have been analyzed for PCC with GC-ECD and GC-MS in the ECNI mode. Regression analysis on PCC concentrations versus sampling year, using the results obtained in GC-ECD analyses based on pooled egg samples and the mean values of the egg samples from 1976 and 1989 respectively, revealed a significant (p

In the past five years the National Institute of Standards and Technology (NIST) has developed several Standard Reference Materials (SRMs) to assist in the validation of measurements of polychlorinated biphenyl (PCB) congeners and chlorinated pesticides in environmental samples. The following natural matrix SRMs have been issued: SRM 1588, Organics in Cod Liver Oil; SRM 1939, PCB Congeners in River Sediment; SRM 1941, Organics in Marine Sediment; SRM 1974, Organics in Mussel Tissue (Mytilus edulis); and SRM 1945, Whale Blubber. All of these SRMs have been analyzed for selected PCB congeners and chlorinated pesticides, and three of these materials (SRMs 1939, 1941, and 1974) have also been analyzed for polycyclic aromatic hydrocarbons (PAHs). In 1982, SRM 1649, Urban Dust/Organics, was issued with certified concentrations for selected PAHs. Recently, SRM 1649 has been analyzed for selected PCB congeners and chlorinated pesticides. Toxaphene measurements have not been made at NIST for these SRMs; however, these SRMs represent the environmental matrices that are typically analyzed for toxaphene. Recommended values for toxaphene concentrations could be established on any of these materials through interlaboratory comparison exercises involving laboratories experienced in making toxaphene measurements. In this paper we describe these SRMs and discuss their suitability as potential reference materials for toxaphene measurements.

An electron capture negative ion mass spectrometric method for quantitative determination of chlorobornanes was tested on selected samples from an arctic marine food chain. The method provided sufficient sensitivity to detect residues down to 0.3 ppb. Detailed area counts at prescribed mass scans were collected and processed for two selected samples, a fish and a neuston sample. Total chlorobornane concentrations were, 1.6 ng/g for the neuston and 12.8 ng/g for the pollack. Chlorine homologue class (Cl 6 to Cl 10 ) concentrations for each sample were determined. Relative homologue amounts linked the neuston to an atmospheric input since it had highest concentrations of Cl 6 , which is more prevalent in air, while the fish had a higher relative levels of Cl 8 and Cl 9&10 homologues indicative of the tendency for these more lipophilic homologues to concentrate in fish lipids.

The gaschromatographic determination of Toxaphene and its residues in different environmental compartments is often difficult. This problem can satisfactorily be overcome if purely high chlorinated bornane derivatives are available. In the present work it was able to isolate large quantities of eleven of these highly chlorinated Toxaphene components (7–17) and to elucidate their structures with the help of spectroscopical methods.

The theoretical number of chlorinated bornanes, the basic skeleton of toxaphene, has been determined. In addition, the distribution on different chlorine content as well as a short consideration of the symmetry and optical isomerism is given.

Special Issue Tools for the Reach Programme - Analytical Methods for the Evaluation of Industrial Contaminants : Foreword