Intercorrelations of Chlorinated Paraffins, Dechloranes, and Legacy Persistent Organic Pollutants in 10 Species of Marine Mammals from Norway, in Light of Dietary Niche.

Short-, medium-, and long-chain chlorinated paraffins (CPs) (SCCPs, MCCPs, and LCCPs) and dechloranes are chemicals of emerging concern; however, little is known of their bioaccumulative potential compared to legacy contaminants in marine mammals. Here, we analyzed SCCPs, MCCPs, LCCPs, 7 dechloranes, 4 emerging brominated flame retardants, and 64 legacy contaminants, including polychlorinated biphenyls (PCBs), in the blubber of 46 individual marine mammals, representing 10 species, from Norway. Dietary niche was modeled based on stable isotopes of nitrogen and carbon in the skin/muscle to assess the contaminant accumulation in relation to diet. SCCPs and dechlorane-602 were strongly positively correlated with legacy contaminants and highest in killer (Orcinus orca) and sperm (Physeter macrocephalus) whales (median SCCPs: 160 ng/g lw; 230 ng/g lw and median dechlorane-602: 3.8 ng/g lw; 2.0 ng/g lw, respectively). In contrast, MCCPs and LCCPs were only weakly correlated to recalcitrant legacy contaminants and were highest in common minke whales (Balaenoptera acutorostrata; median MCCPs: 480 ng/g lw and LCCPs: 240 ng/g lw). The total contaminant load in all species was dominated by PCBs and legacy chlorinated pesticides (63-98%), and MCCPs dominated the total CP load (42-68%, except 11% in the long-finned pilot whale Globicephala melas). Surprisingly, we found no relation between contaminant concentrations and dietary niche, suggesting that other large species differences may be masking effects of diet such as lifespan or biotransformation and elimination capacities. CP and dechlorane concentrations were higher than in other marine mammals from the (sub)Arctic, and they were present in a killer whale neonate, indicating bioaccumulative properties and a potential for maternal transfer in these predominantly unregulated chemicals.

Development of a supramolecular solvent-based extraction method for application to quantitative analyses of a wide range of organic contaminants in indoor dust.

This study investigates the efficacy of supramolecular solvent (SUPRAS) in extracting a diverse spectrum of organic contaminants from indoor dust. Initially, seven distinct SUPRAS were assessed across nine categories of contaminants to identify the most effective one. A SUPRAS comprising Milli-Q water, tetrahydrofuran, and hexanol in a 70:20:10 ratio, respectively, demonstrated the best extraction performance and was employed for testing a wider array of organic contaminants. Furthermore, we applied the selected SUPRAS for the extraction of organic compounds from the NIST Standard Reference Material (SRM) 2585. In parallel, we performed the extraction of NIST SRM 2585 with conventional extraction methods using hexane:acetone (1:1) for non-polar contaminants and methanol (100%) extraction for polar contaminants. Analysis from two independent laboratories (in Norway and the Czech Republic) demonstrated the viability of SUPRAS for the simultaneous extraction of twelve groups of organic contaminants with a broad range of physico-chemical properties including plastic additives, pesticides, and combustion by-products. However, caution is advised when employing SUPRAS for highly polar contaminants like current-use pesticides or volatile substances like naphthalene.

Mapping of common bunt resistance gene Bt9 in wheat.

KEY MESSAGE: The Bt9 resistance locus was mapped and shown to be distinct from the Bt10 locus. New markers linked to Bt9 have been identified and may be used to breed for resistance towards the seed-borne disease. Increasing organic wheat production in Denmark, and in other wheat-producing areas, in conjunction with legal requirements for organic seed production, may potentially lead to a rise in common bunt occurrence. As systemic pesticides are not used in organic farming, organic wheat production systems may benefit from genetic resistances. However, little is known about the underlying genetic mechanisms and locations of the resistance factors for common bunt resistance in wheat. A double haploid (DH) population segregating for common bunt resistance was used to identify the chromosomal location of common bunt resistance gene Bt9. DH lines were phenotyped in three environments and genotyped with DArTseq and SSR markers. The total length of the resulting linkage map was 2882 cM distributed across all 21 wheat chromosomes. Bt9 was mapped to the distal end of chromosome 6DL. Since wheat common bunt resistance gene Bt10 is also located on chromosome 6D, the possibility of their co-location was investigated. A comparison of marker sequences linked to Bt9 and Bt10 on physical maps of chromosome 6D confirmed that Bt9 and Bt10 are two distinct resistance factors located at the distal (6DL) and proximal (6DS) end, respectively, of chromosome 6D. Five new SSR markers Xgpw4005-1, Xgpw7433, Xwmc773, Xgpw7303 and Xgpw362 and many SNP and PAV markers flanking the Bt9 resistance locus were identified and they may be used in the future for marker-assisted selection.

High Concentrations of Organic Contaminants in Air from Ship Breaking Activities in Chittagong, Bangladesh.

The beaches on the coast of Chittagong in Bangladesh are one of the most intense ship breaking areas in the world. The aim of the study was to measure the concentrations of organic contaminants in the air in the city of Chittagong, including the surrounding ship breaking areas using passive air samplers (N = 25). The compounds detected in the highest amounts were the polycyclic aromatic hydrocarbons (PAHs) and short-chain chlorinated paraffins (SCCPs), whereas dichlorodiphenyltrichloroethanes (DDTs), hexachlorobenzene (HCB), and polychlorinated biphenyls (PCBs) were several orders of magnitude lower in comparison. PCBs, PAHs, and HCB were highest at sites near the ship breaking activities, whereas DDTs and SCCPs were higher in the urban areas. Ship breaking activities likely act as atmospheric emission sources of PCBs, PAHs, and HCB, thus adding to the international emphasis on responsible recycling of ships. Concentrations of PAHs, PCBs, DDTs, HCB, and SCCPs in ambient air in Chittagong are high in comparison to those found in similar studies performed in other parts of Asia. Estimated toxic equivalent quotients indicate elevated human health risks caused by inhalation of PAHs at most sites.

Stepping-up accurate quantification of chlorinated paraffins: Successful certification of the first matrix reference material.

BACKGROUND: Chlorinated paraffins (CPs) are industrial chemicals categorised as persistent organic pollutants because of their toxicity, persistency and tendency to long-range transport, bioaccumulation and biomagnification. Despite having been the subject of environmental attention for decades, analytical methods for CPs still struggle reaching a sufficient degree of accuracy. Among the issues negatively impacting the quantification of CPs, the unavailability of well-characterised standards, both as pure substances and as matrix (certified) reference materials (CRMs), has played a major role. The focus of this study was to provide a matrix CRM as quality control tool to improve the comparability of CPs measurement results. RESULTS: We present the process of certification of ERM®-CE100, the first fish reference material assigned with certified values for the mass fraction of short-chain and medium-chain chlorinated paraffins (SCCPs and MCCPs, respectively). The certification was performed in accordance with ISO 17034:2016 and ISO Guide 35:2017, with the value assignment step carried out via an intercomparison of laboratories of demonstrated competence in CPs analysis and applying procedures based on different analytical principles. After confirmation of the homogeneity and stability of the CRM, two certified values were assigned for SCCPs, depending on the calibrants used: 31 ± 9 µg kg-1 and 23 ± 7 µg kg-1. The MCCPs certified value was established as 44 ± 17 µg kg-1. All assigned values are relative to wet weight in the CRM that was produced as a fish paste to enhance similarity to routine biota samples. SIGNIFICANCE AND NOVELTY: The fish tissue ERM-CE100 is the first matrix CRM commercially available for the analysis of CPs, enabling analytical laboratories to improve the accuracy and the metrological traceability of their measurements. The certified CPs values are based on results obtained by both gas and liquid chromatography coupled with various mass spectrometric techniques, offering thus a broad validity to laboratories employing different analytical methods and equipment.

Chlorinated paraffins and dechloranes in free-range chicken eggs and soil around waste disposal sites in Tanzania.

Electronic waste is a source of both legacy and emerging flame retardants to the environment, especially in regions where sufficient waste handling systems are lacking. In the present study, we quantified the occurrence of short- and medium chain chlorinated paraffins (SCCPs and MCCPs) and dechloranes in household chicken (Gallus domesticus) eggs and soil collected near waste disposal sites on Zanzibar and the Tanzanian mainland. Sampling locations included an e-waste facility and the active dumpsite of Dar es Salaam, a historical dumpsite in Dar es Salaam, and an informal dumpsite on Zanzibar. We compared concentrations and contaminant profiles between soil and eggs, as free-range chickens ingest a considerable amount of soil during foraging, with potential for maternal transfer to the eggs. We found no correlation between soil and egg concentrations or patterns of dechloranes or CPs. CPs with shorter chain lengths and higher chlorination degree were associated with soil, while longer chain lengths and lower chlorination degree were associated with eggs. MCCPs dominated the CP profile in eggs, with median concentrations ranging from 500 to 900 ng/g lipid weight (lw) among locations. SCCP concentrations in eggs ranged from below the detection limit (LOD) to 370 ng/g lw. Dechlorane Plus was the dominating dechlorane compound in all egg samples, with median concentrations ranging from 0.5 to 2.8 ng/g lw. SCCPs dominated in the soil samples (400-21300 ng/g soil organic matter, SOM), except at the official dumpsite where MCCPs were highest (65000 ng/g SOM). Concentrations of dechloranes in soil ranged from below LOD to 240 ng/g SOM, and the dominating compounds were Dechlorane Plus and Dechlorane 603. Risk assessment of CP levels gave margins of exposure (MOE) close to or below 1000 for SCCPs at one location.

Spatial trends of chlorinated paraffins and dechloranes in air and soil in a tropical urban, suburban, and rural environment.

There are large knowledge gaps concerning environmental levels and fate of many organic pollutants, particularly for chemicals of emerging concern in tropical regions of the Global South. In this study, we investigated the levels of chlorinated paraffins (CPs) and dechloranes in air and soil in rural, suburban, and urban regions in and around Dar es Salaam, Tanzania. Samples were also collected near the city's main municipal waste dumpsite and an electronic waste (e-waste) handling facility. In passive air samples, short chain CPs (SCCPs) dominated, with an average estimated concentration of 22 ng/m3, while medium chain CPs (MCCPs) had an average estimated concentration of 9 ng/m3. The average estimated air concentration of ∑dechloranes (Dechlorane Plus (DP) + Dechlorane 602 + Dechlorane 603) was three to four orders of magnitudes lower, 2 pg/m3. In soil samples, MCCPs dominated with an average concentration of 640 ng/g dw, followed by SCCPs with an average concentration of 330 ng/g dw, and ∑dechloranes with an average concentration of 0.9 ng/g dw. In both air and soil, DP was the dominating dechlorane compound. Urban pulses were observed for CPs and dechloranes in air and soil. CPs were in addition found in elevated levels at the municipal waste dumpsite and the e-waste handling facility, while DPs were found in elevated levels at the e-waste handling facility. This suggests that waste handling sites represent important emission sources for these pollutants. Investigations into seasonal trends and environmental fate of CPs and dechloranes showed that monsoonal rain patterns play a major role in governing air concentrations and mobility, particularly for the less volatile MCCPs and dechloranes. This study is the first to report levels of CPs in air from sub-Saharan Africa, and DP, Dechlorane 602, and Dechlorane 603 in soil from sub-Saharan Africa.

Distribution profiles of selected organic pollutants in soils and sediments of industrial, residential and agricultural areas of South Africa.

Currently very little data exists on the presence of persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) in the South African environment. To address this data gap a preliminary study of a highly industrialised area of South Africa, the Vaal Triangle, was done. Soil and sediment samples from the Vaal Triangle, as well as other areas in central South Africa, were analysed with high resolution gas chromatography-high resolution mass spectrometry (HRGC/HRMS) for the presence of PAHs, polychlorinated biphenyls (PCBs), dioxin-like chemicals and organochlorine pesticides (OCPs). Results showed that these chemicals are present in the South African environment with concentrations ranging between 39,000 ng g(-1) for SigmaPAHs and 0.01 ng g(-1) for dicofol. Principal component analysis (PCA) indicated different pollution sources in industrial and agricultural areas.

Concentrations of selected chemicals in indoor air from Norwegian homes and schools.

Both building materials and consumer products have been identified as possible sources for potentially hazardous substances like phthalates, polychlorinated biphenyls (PCBs), organophosphorous flame retardants (OPFRs), polybrominated diphenyl ethers (PBDEs) and short chain chlorinated paraffins (SCCPs) in indoor air. Thus, indoor air has been suggested to contribute significantly to human exposure to these chemicals. There is lack of data on the occurrence of several of the aforementioned chemicals in indoor air. Therefore, indoor air (gas and particulate phase) was collected from 48 households and 6 classrooms in two counties in Norway. In both the households and schools, median levels of low molecular weight phthalates (785 ng/m3), OPFRs (55 ng/m3) and SCCPs (128 ng/m3) were up to 1000 times higher than the levels of PCBs (829 pg/m3) and PBDEs (167 pg/m3). Median concentrations of dimethyl phthalate (DMP), diethyl phthalate (DEP), di-isobutyl phthalate (DiBP) and SCCPs were 3-6 times higher in households compared to schools. The levels of OPFRs, PCBs and PBDEs were similar in households and schools. In univariate analysis, the indoor concentrations of different environmental chemicals were significantly affected by location of households (OPFRs), airing of living room (some PCBs and PBDEs), presence of upholstered chair/couch (OPFRs), pet animal hold (some PBDEs) and presence of electrical heaters (selected PCBs and PBDEs). Significant correlations were also detected for the total size of households with OPFRs, frequency of vacuuming the living room with selected PCBs and PBDEs, frequency of washing the living room with selected PCBs and the total number of TVs in the households with selected phthalates and SCCPs. Finally, intake estimates indicated that indoor air contributed more or equally to low molecular weight phthalates and SCCPs exposure compared to food consumption, whereas the contribution from indoor air was smaller than the dietary intake for the other groups of chemicals.

Elevated levels of polybrominated diphenyl ethers (PBDEs) in fish from Lake Mjøsa, Norway.

Surprisingly high levels of PBDEs (polybrominated diphenyl ethers) in fish from Lake Mjøsa watercourse initialized a more detailed study of PBDE contamination in the Lake Mjøsa region as well as fish from other lakes in southeast Norway. With exception of the fish from Lake Mjøsa, the sum concentration of PBDEs in trout was, on a wet weight (ww) basis, in the range of 0.3-40 ng/g (21-1215 ng/g lipid weight (lw)) in fish fillet and 39-446 ng/g (125-915 ng/g lw) in burbot liver. The PBDE levels in fish from Lake Mjøsa, was found in the range of 72-1120 ng/g ww (2348-16,753 ng/g lw) in trout and 156-2265 ng/g ww (4201-45,144 ng/g lw) in burbot. It was later confirmed that the elevated levels in Lake Mjøsa were mainly caused by the release of PBDEs to the water from a textile manufacturer in the town of Lillehammer. In addition to PBDE levels in fish we also present information on the spatial distribution of PBDEs in air around the Mjøsa watercourse, based on the complementary use of passive air samples and analysis of moss, including data on measured air concentrations. The results confirm the presence of an active source of atmospheric PBDEs in the region of Lillehammer. Although this source appears to have a limited impact on atmospheric levels towards the southern reaches of the lake, it could still be a significant source of PBDEs to the lake as a whole. However, more research is needed to better understand and quantify the relative importance of various sources and pathways for which PBDEs enter Lake Mjøsa in order to support the development of future control strategies.

Evaluation of four mass spectrometric methods for the gas chromatographic analysis of polychlorinated n-alkanes.

The suitability of four mass spectrometric methods for the gas chromatographic analysis of polychlorinated n-alkanes (PCAs, also called chlorinated paraffins) was evaluated and compared using spiked and fish liver samples. Electron ionization tandem mass spectrometry (EI-MS/MS) as well as electron capture negative ionization (ECNI) combined with low and high resolution mass spectrometry and CH4/CH2Cl2-negative ion chemical ionization (NICI) low resolution mass spectrometry were investigated. All methods showed an accuracy of <21% for the analysis of spiked fish samples. However, the analysis of real samples showed deviations of up to 46% between the four mass spectrometric methods. The influence of the selected reference standard on quantification was also evaluated. The use of a quantification standard with a degree of chlorination deviating from that of the sample can result in differences of > 100% for the ECNI methods. EI-MS/MS and CH4/CH2Cl2-NICI led to errors of maximum 17% and 33%, respectively, independent from the degree of chlorination of the used reference standard.

Polychlorinated alkanes in fish from Norwegian freshwater.

Short-chain polychlorinated alkanes (sPCAs) have been measured in freshwater fish samples from different lakes all over Norway and from the Norwegian Arctic. The analyses were performed with high-resolution GC coupled to high-resolution MS in electron capture negative ion mode. The species investigated were trout, Arctic char, and burbot (Lota lota). Muscle tissue in the lake trout and Arctic char, and liver in burbot, were selected for analyses because of their high lipid content. SigmasPCA concentration ranged from 108 to 3700 ng/g fat. The highest value was found in the south of Norway near an industrial area.

Evaluating the environmental fate of short-chain chlorinated paraffins (SCCPs) in the Nordic environment using a dynamic multimedia model.

Short chain chlorinated paraffins (SCCPs) raise concerns due to their potential for persistence, bioaccumulation, long-range transport and adverse effects. An understanding of their environmental fate remains limited, partly due to the complexity of the mixture. The purpose of this study was to evaluate whether a mechanistic, integrated, dynamic environmental fate and bioaccumulation multimedia model (CoZMoMAN) can reconcile what is known about environmental emissions and human exposure of SCCPs in the Nordic environment. Realistic SCCP emission scenarios, resolved by formula group, were estimated and used to predict the composition and concentrations of SCCPs in the environment and the human food chain. Emissions at the upper end of the estimated range resulted in predicted total concentrations that were often within a factor of 6 of observations. Similar model performance for a complex group of organic contaminants as for the well-known polychlorinated biphenyls strengthens the confidence in the CoZMoMAN model and implies a relatively good mechanistic understanding of the environmental fate of SCCPs. However, the degree of chlorination predicted for SCCPs in sediments, fish, and humans was higher than observed and poorly established environmental half-lives and biotransformation rate constants contributed to the uncertainties in the predicted composition and ∑SCCP concentrations. Improving prediction of the SCCP composition will also require better constrained estimates of the composition of SCCP emissions. There is, however, also large uncertainty and lack of coherence in the existing observations, and better model-measurement agreement will require improved analytical methods and more strategic sampling. More measurements of SCCP levels and compositions in samples from background regions are particularly important.

Relevance of 1,2,5,6,9,10-hexabromocyclododecane diastereomer structure on partitioning properties, column-retention and clean-up procedures.

To optimize clean-up procedures for the analysis of alpha-, beta-, and gamma-hexabromocyclododecanes (HBCD) in environmental and biological extracts, their retention behavior on silica gel and florisil was investigated using diverse mobile-phase solvents and accounting for matrix effects. The beta-diastereomer, relative to the alpha- and gamma-diastereomers, is substantially retained on both florisil and silica gel regardless of the solvent used. The beta-diastereomer is therefore prone to undergo selective loss during clean-up. This sequence is counterintuitive to sequences based on reverse-phase chromatography with a C18-column, in which the alpha- (and not the beta-) isomer is eluted first when using a polar solvent. There has been some discrepancy regarding the structures of these diastereomers in the literature, with structures based on X-ray crystallography only becoming recently available. Based on these X-ray crystal structures, physical-chemical properties (the octanol-water partitioning constant, the Henry's law constant, subcooled liquid vapour pressures and subcooled liquid water solubilities) of the HBCD diastereomers were estimated using the quantum-chemistry based software COSMOtherm, and were found to differ from previously calculated values using different structures (e.g. log K(aw) for alpha-, beta-, and gamma-HBCD are here estimated to be -8.3, -9.3 and -8.2 respectively). Hypothesis relating differences in structure to physical-chemical properties and retention sequences are presented. The extra retention of the beta-diastereomer on silica gel and florisil is likely because it can form both greater specific (i.e. polar) and non-specific (i.e. non-polar) interactions with surfaces than the other diastereomers. Non-specific interactions can also account for the counter-intuitive elution orders with C(18)-reverse-phase chromatography. These results indicate that care should be taken when isolating HBCDs and other molecular diastereomers from environmental and biological samples, and that reported concentrations of beta-HBCD in the literature may be negatively biased.

Dioxin-like chemicals in soil and sediment from residential and industrial areas in central South Africa.

Persistent organic pollutants (POPs) are a global concern due to their ubiquitous presence and toxicity. Currently, there is a lack of information regarding POPs from South Africa. Here we report and interpret concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), -dibenzofurans (PCDFs) and co-planar-biphenyls (PCBs) in soils and sediments collected from central South Africa. High resolution gas chromatography-high resolution mass spectrometry (HRGC/HRMS) and the H4IIE-luc bio-assay were used to identify and quantify individual PCDD/F congeners and to report the total concentration of 2,3,7,8-tetrachloro dibenzo-p-dioxin equivalents (TCDD-EQ), respectively. TCDD-EQs determined by use of the bio-assay, and concentrations of WHO(2005)-TEQ (toxic equivalents) determined by chemical analysis, were similar. The limit of detection (LOD) for the bio-assay was 0.82 and 2.8 ng TCDD-EQ kg(-1), dw for sediment and soil, respectively. EQ20 concentrations determined by use of the bio-assay ranged from