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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.

Two interlaboratory studies on individual toxaphene congeners have been organised by the project Quality Assurance of Information for Marine Environmental Monitoring in Europe (QUASIMEME). Fifteen laboratories analysed two standard solutions in the first study and 13 laboratories analysed a standard solution and two cleaned biota extracts in the second study. The coefficients of variation obtained for the standard solutions were 6-21% and for the cleaned extracts 16-39%. Although the results were comparable to those of other studies, further improvement in the level of agreement between the participating laboratories was considered possible. (C) 2000 Elsevier Science Ltd.

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.

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.

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.

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.

The methodology presented combines mass selective detection technology for routine automated total toxaphene determinations with electron capture detection confirmation of congener results. Total toxaphene values were calculated using a custom developed series of data analysis macroinstructions (macros) that eliminate potential interferences and collate peak areas. These macros create multi-level calibration tables with results automatically corrected for surrogate and performance standards. It is possible to produce congener data that provides results from both detectors in one report from a single injection.

Levels and distribution of eight compounds of technical toxaphene (CTTs) were determined in different marine species (seals, cetaceans, birds, and fish). The eight CTTs included six commercially available and two chlorobornanes prepared in our lab. These congeners were present in all investigated samples. In agreement with earlier studies, the octachlorobornane B8-1413 (P-26) and the nonachlorobornane B9-1679 (P-50) were the most abundant congeners in most of the samples. In seal blubber, B8-1413 (P-26) and B9-1679 (P-50) contributed with up to ∼80% (Weddell seal) to the sum of the eight CTTs. In seals from the northern hemisphere the nonachlorobornane was more abundant while in those from the southern hemisphere (Antarctic and Namibia), the octachlorobornane B8-1413 (P-26) usually appeared at higher concentrations. Depending on the species the contribution of the other congeners varied significantly. B9-1025 (P-62) ranged from 2–20%, B8-1412 was found at 4–25% with highest contribution in birds, and B8-2229 (P-44) was found at 5–15%. The remaining three congeners B7-1453, B8-1414 (P- 40), and B8-1945 (P-41) were lower abundant except B8-1414 (P-40) which was found at high contribution in liver and kidney of birds. The sum of the eight CTTs ranged from 4 μg/kg to 1.4 mg/kg, depending on the species and region. In most of the seal blubber samples, PCBs and DDT were more abundant (factor 2–20) but Antarctic Weddell seals showed higher CTT levels than PCBs and DDT.

Theoretical molecular descriptors have been calculated for 36 polychlorinated bornanes, the majority compound class of the insecticide Toxaphene. The results demonstrate that thermodynamic stability by the use of molecular structural energies can be used as a general parameter for persistence. Since these descriptors agree well with polychlorinated bornanes found in the environment, these compounds should be included as important indicator compounds in future trace analytical investigations of polychlorinated bornanes and also within experimental metabolism studies to investigate potential toxic metabolites. Reactivity descriptors such as electronaffinity, hardness, LUMO location and atomic charges may guide to potential chemical reactions like the dechlorination of polychlorinated bornanes in reductive environment. Further it is advised to use these descriptors and other new potential ones in combination with experimental degradation and toxicology studies to explore the relationship between molecular structure and biological effects of chlorobornanes.

A method for the congener-specific analysis of toxaphene in eggs of seabirds from a monitoring program from the northern part of Germany was carried out. The method was optimized in most steps of the procedure: injection temperature, HRGC with an HT-8 column, ion source temperature and the MS detection mode NCI/SIM measuring the isotope clusters of [M] , [M-Cl]-, [M-HCl]- and [M-2Cl]-. The suitability of 1,4-exo, 7,8,9,10,10-heptachloro-5-methoxytricyclo [5,2,1,0(2,6)]dec-3,8-diene as internal standard was demonstrated. 14 toxaphenes with Parlar numbers and more than 60 unknown toxaphenes could be identified. Spatial and temporal trends of toxaphene contamination are presented by using the Parlar 22 components standard for quantification.

Human milk from residents ofnorthern Canada (Keewatin) was compared to that in national surveys of southern Canada with respect to residues of toxaphene, PCBs, PCDD/PCDFs, chlordane, and several other persistant organic compounds. Concentrations of toxaphene were approximately ten-fold higher in specimens from Keewatin than from the south. Toxaphene concentrations in samples from the Great Lakes Basin collected in 1992 were not significantly (p

A method for the determination of environmentally relevant toxaphene congeners (eg chlorinated bornanes (CHBs) in serum is described. Four chlorinated bornane congeners are predominant in serum.

Toxaphene is a pesticide whose use was banned in North America because of concerns regarding its toxicity. To obtain better data on the metabolism and toxicity of toxaphene in primates, a one year feeding study was carried out in cynomologous monkeys at a dose of 1 mg/kg/day for one year. Levels of toxaphene residues in blood and adipose tissue during the dosing period were measured by GC-ECD and ECNI GCMS. The dosing toxaphene mixture was found to be extensively metabolized. Four chlorinated bornane congeners were the predominate residues found in the tissue samples. Blood levels of toxaphene residues plateaued at 40 ppb, adipose levels at approximately 4000 ppb. Kidney, liver, feces and urine were analyzed for toxaphene residues after necropsy.