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A time trend study focusing on ski waxing technicians’ exposure to perfluorinated chemicals (PFCs) from fluorinated wax fumes was performed in 2007/2008. Levels of eight perfluorocarboxylates and three perfluorosulfonates were analyzed in monthly blood samples from eight technicians. Samples were collected before the ski season, i.e., preseason, then at four FIS World Cup competitions in cross country skiing, and finally during an unexposed 5-month postseason period. The perfluorinated carboxylates perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUnDA) bioaccumulate, and continued exposure may contribute to elevated levels in ski technicians compared to the general population. The wax technicians’ median blood level of PFOA is 112 ng/mL compared to 2.5 ng/mL in the general Swedish population. A significant correlation was found between number of working years and levels of perfluorocarboxylates. The PFOA levels in three technicians with “low” initial levels of PFOA (<10.0 ng/mL in preseason blood) increased by 254, 134, and 120%, whereas five technicians with “high” initial levels (>100 ng/mL in preseason sample) were at steady state. PFHxA is suggested to have a short half-life in humans relative the other perfluorocarboxylates. The levels of perfluorosulfonates were unaffected by the wax exposure.

One possible way of monitoring plastic particles in sea water is by imaging spectroscopic measurements on filtrates. The idea is that filters from seawater sampling can be imaged in many wavelengths and that a multivariate data analysis can give information on (1) spatial location of plastic material on the filter and (2) composition of the plastic materials. This paper reports on simulated samples, with spiked reference plastic particles and real seawater filtrates containing microplastic pollutants. These real samples were previously identified through visual examination in a microscope. The samples were imaged using three different imaging systems. The different wavelength ranges were 375–970 nm, 960–1662 nm and 1000–2500 nm. Data files from all three imaging systems were analysed by hyperspectral image analysis. The method using the wavelength span 1000–2500 nm was shown to be the most applicable to this specific type of samples and gave a 100% particle recognition on reference plastic, above 300 μm, and an 84% pixel recognition on household polyethylene plastic. When applied to environmental samples the technique showed an increase in identified particles compared with visual investigations. These initial tests indicate a potential underestimation of microplastics in environmental samples. This is the first study to demonstrate that hyperspectral imaging techniques can be used to study microplastics down to 300 μm, which is a common size limit used in microplastic surveys.

One possible way of monitoring plastic particles in sea water is by imaging spectroscopic measurements on filtrates. The idea is that filters from seawater sampling can be imaged in many wavelengths and that a multivariate data analysis can give information on (1) spatial location of plastic material on the filter and (2) composition of the plastic materials. This paper reports on simulated samples, with spiked reference plastic particles and real seawater filtrates containing microplastic pollutants. These real samples were previously identified through visual examination in a microscope. The samples were imaged using three different imaging systems. The different wavelength ranges were 375–970 nm, 960–1662 nm and 1000–2500 nm. Data files from all three imaging systems were analysed by hyperspectral image analysis. The method using the wavelength span 1000–2500 nm was shown to be the most applicable to this specific type of samples and gave a 100% particle recognition on reference plastic, above 300 μm, and an 84% pixel recognition on household polyethylene plastic. When applied to environmental samples the technique showed an increase in identified particles compared with visual investigations. These initial tests indicate a potential underestimation of microplastics in environmental samples. This is the first study to demonstrate that hyperspectral imaging techniques can be used to study microplastics down to 300 μm, which is a common size limit used in microplastic surveys.

The analysis of legacy environmental contaminants, such as polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), using high resolution gas chromatography (HRGC) is well established and universally accepted. The use of an alternative separation technique, such as packed column supercritical fluid chromatography (pSFC), may be of interest as a fast, green, and cost effective method of analyzing environmental samples. The technique is amenable to a broad range of chemical compounds and could facilitate the simultaneous analysis of multiple compound classes as well as the inclusion of thermally labile compounds in a single targeted analysis. The recent re-emergence of this technology due to the introduction of more robust and efficient instrumentation may result in an increased acceptance of pSFC analytical techniques in this area. Herein, the first reported analytical separation of PCDDs and PCDFs by pSFC is described and its separation capabilities are compared with established HRGC protocols. Elution profiles of 2,3,7,8-substituted PCDDs and PCDFs were examined and the separation of PCDD/PCDF homologue groups was found to be comparable to those accomplished using HRGC. Similarly, the resolution of tetrachlorodibenzo-p-dioxin (TCDD) congeners, as required by current regulatory methods utilizing HRGC, was demonstrated and the separation of possible co-eluting PCDD/PCDF congeners was examined and compared to that achieved using popular HRGC capillary columns. The possibility of concurrent analysis of toxic polychlorinated biphenyls (PCBs) with PCDDs and PCDFs using the developed pSFC method was also investigated. The effective separation of these environmental contaminants obtained using pSFC and subsequent detection utilizing atmospheric pressure photoionization tandem mass spectrometry at environmentally relevant levels demonstrates the promise associated with this technique for the analysis of environmental extracts.

Analysis of the brominated flame retardant hexabromocyclododecane (HBCDD) is characterized by the separation of its three predominant diastereomers. This analysis is typically performed using reversed phase liquid chromatography (RPLC) coupled with mass spectrometric (MS) detection with analysis times in the order of 10 minutes or greater. Here we describe a rapid method using supercritical CO2and methanol to baseline separate the three most abundant HBCDD diastereomers within a three minute run time using a High Strength Silica (HSS) C18 1.8 μm particle size column. A unique elution order of the α-, β- and γ-HBCDD diastereomers using supercritical CO2was observed, and can be used as an orthogonal separation for further confidence in diastereomer identification when used in conjuction with RPLC. A tandem quadrupole mass spectrometer with negative mode electrospray ionization was used for detection, operating in multiple reaction monitoring (MRM) mode. Ionization was enhanced by the addition of a make-up flow, which was introduced to the post-column effluent. Method limit of detection (LOD) and limit of quantification (LOQ) for α-, β- and γ-HBCDD were based on peak-to-peak signal to noise ratios of greater than 3 or 10, respectively. The LOD for all HBCDD diastereomers as solvent standards was 100 fg on-column, and LOQs 500 fg on-column for α- and γ-HBCDD and 250 fg on-column for β-HBCDD. In order to test the efficiency of this method, small subsets of complex human serum and whale blubber extracts were analyzed using this method, resulting in positive detections in samples of α-HBCDD.

Established risk factors for left ventricular hypertrophy (LVH) are hypertension, diabetes, and obesity. However, as these risk factors explain only part of the variation in left ventricular mass, we investigated whether persistent organic pollutants (POPs) might also play a role in LVH, because exposure to polychlorinated biphenyl 126 induced cardiac growth in rats.

Brominated flame retardants BFRs have been used extensively and are considered ubiquitous contaminants. To evaluate exposure to brominated flame retardants within an electronic recycling facility personal air monitoring was done during a two year period. A total of 22 polybrominated diphenyl ethers PBDEs and 2 other bromine containing organic compounds have been analysed and evaluated in 17 personal air samples. The most abundant congeners of PBDE was 209 <0.7–61 ng m−3, 183 <0.1–32 ng m−3 indicating the use of the commercial octaBDE mixture, followed by PBDE 99 and 47 <1.3–25 and <0.9–16 ng m−3, respectively. The second most abundant peak in the chromatogram from all samples was identified as 1,2-bis2,4,6-tribromophenyxyethane BTBPE in the concentration range <0.6–39 ng m−3semi-quantitatively calculated against PBDE 191. A second bromine containing compound was also detected, structurally similar to decabromodiphenyl ethane DeBDethane, however no definite identification could be made. The air samples were also evaluated on a work exposure category basis. The workers represented three different categories: dismantlers, other workers and unexposed. There was a significant difference p< 0.05 with the Mann–Whitney test among the dismantlers and the unexposed categories for PBDE congeners 47, 100, 99, 154; 153, 183, 209 and BTBPE. Another observation was that the air concentrations of PBDEs and BTBPE in the breathing zone were negatively correlated p< 0.05 to the amount of recycled material in kg. The present work shows that the exposure to brominated flame retardants varied within the electronic facility and that further research is needed to evaluate how the exposure differs with different products being dismantled as well as how the bioavailability of the different BFRs to humans is related to particle exposure.

To evaluate the sediment quality of selected sites in the catchment area of the River Neckar, an integrative assessment approach was used to assess the ecological hazard potential of dioxin-like sediment compounds. The approach is based on 7-ethoxyresorufin-O-deethylase (EROD) induction in embryonic chicken liver culture and comprehensive chemical analyses of polycyclic aromatic hydrocarbons (priority PAHs according to the US Environmental Protection Agency). The majority of the sediment extracts exhibited high potencies as EROD-inducers. In one sediment sample, which was influenced by a sewage treatment plant, a very high concentration of 930 ng bioassay 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) equivalents (bio-TEQs )/g organic carbon could be determined. However, in none of the samples, more than 6% of the EROD-inducing potency could be explained by the PAHs analyzed chemically. Thus, non-analyzed compounds with EROD-inducing potency were present in the extracts. A fractionation of sediment samples according to pH allowed to localize the major part of EROD-inducing compounds in the neutral fractions. However, a significant portion of the EROD induction could also be explained by the acidic fractions. Following the concept of the Sediment Quality Triad according to Chapman, in situalterations of macrozoobenthos were examined. A comparison of the results predicted by the EROD assay and chemical analyses with alterations in situ, as measured by means of the saprobic index and the ecotoxicological index according to Carmargo, revealed a high ecological relevance of the results of bioassays and chemical analyses for major sites.

A rapid increase in the incidence of non-Hodgkin lymphoma (NHL) has been reported in many countries. Exposure to certain pesticides or organochlorines has been shown to be a risk factor. Epstein–Barr virus (EBV) is a human herpesvirus that has been associated with some subgroups of NHL, such as Burkitt lymphoma and lymphomas related to severe immunosuppression. In this study we measured concentrations of dioxins and dibenzofurans in 33 NHL cases and 39 surgical controls. For 23 of the cases and 32 of the controls EBV titers were also available. Median titer of antibodies to EBV early antigen (EA) IgG was higher in patients than in controls. Concentrations of dioxins and dibenzofurans were divided into two groups according to the median concentration for the controls. Unconditional logistic regression analysis was performed adjusting for sex, age, and body mass index. For several higher chlorinated congeners increased risk was found for patients in the high-concentration and high-titer group. For toxic equivalency factor >27.79 and EA>80 an odds ratio of 2.8 with 95% confidence interval 0.52–18 was calculated. These results indicated that current exposure to certain organochlorines in combination with EBV might increase the risk for NHL.

Unique solvent properties of water, which can be changed by adjusting the temperature, were fully exploited to extract low polarity organic pollutants from soil samples. Solubility enhancement of the non-polar compounds due to the temperature increase of water together with enhanced thermal desorption and compounds’ vapour pressures theoretically and in practice opens the way to extract this kind of compound with pure water. Pressurised hot water extraction (PHWE), here defined as both water and steam extraction, of spiked polychlorinated dibenzofurans (PCDFs) from sand was investigated under different conditions. Optimum extraction conditions for these hydrophobic compounds were found at temperatures between 300 °C and 350 °C. Most effective extraction took place in the gas phase at a pressure of 50 atm. With steam at 300 °C and 50 atm quantitative extraction (compared to Soxhlet extraction) of polychlorinated naphthalenes from real industrial soil was achieved. Additionally, compared to the values obtained by an international laboratory comparison study, the toxicity of the soil, caused by PCDFs, was reduced at least 90% using PHWE. In most cases the RSD was less than 20%, which showed good repeatability of the whole analytical method including the PHWE step.

Adequate multivariate structure-activity relationships (SARs) were calculated by partial least-squares (PLS) predicting the complete uptake and elimination curves for 63 PCDFs (tetra to hexa chlorinated congeners) in adipose tissue for guinea pig, hamster, mouse and rat. The SARs for uptake and elimination for these 63 congeners were calculated from a experimental determined data set which contained 16 congeners. The models were tested by selecting a training set (12 congeners) from which predictions were computed for a validation set (4 congeners). This validation set was selected from the 16 congeners by means of a principal component analyses (PCA) of 13 physico-chemical properties of the PCDFs. Models using only the half-life (t½) for elimination showed less predictive capability than modelling the complete uptake and elimination curves.Loading plots from the PLS analyses revealed that different physico-chemical properties were responsible for uptake and elimination. The ionisation potential, the lowest unoccupied molecular orbital, the octanol/water partition coefficient, the number of lateral chlorine atoms and the UV-maximum wavelength are important variables in modelling elimination. The dipole moment, GC-retention times and the number of non-lateral chlorine atoms are more influential in the uptake and distribution steps. The molecular weight and the total number of chlorine atoms play a role in both processes.