| 1. |
- Bjurlid, Filip, 1978-
(författare)
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Polybrominated dibenzo-p-dioxins and furans : from source of emission to human exposure
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Brominated flame retardants (BFRs), which are ubiquitous in modern life and the environment, are the major source for polybrominated dibenzo-p-dioxins and furans (PBDD/Fs). The knowledge about PBDD/Fs is lim-ited compared to other environmental pollutants, even though PBDD/Fs show similar toxicity as polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) which are considered to be among the most toxic man-made substances. The aim of the thesis was to provide a better understanding of PBDD/Fs by investigating the occurrence and distribution of PBDD/Fs in the following matrices: soot and gas from an accidental fire site which is a typical source of emission, blubber from marine mammals living in both far remote areas as well as areas close to anthropogenic sources, and finally in human milk from ten nursing mothers.PBDD/Fs was detected in blubber from pilot whales sampled around Faroe Islands, which proved the occurrence in marine mammals in a far remote area. The findings of PBDD/Fs in blubber from Baltic ringed seals showed slightly higher concentrations compared to the pilot whales, which is expected since the Baltic Sea in among the world’s most contam-inated water areas. In the pilot whales and the ringed seals, the average contribution from PBDD/Fs to the total (PCDD/F+PBDD/F) Total Equiv-alent Quantity (TEQ) was low, (1-8%). In gas and soot samples from the accidental fire site, PBDD/Fs were detected in all samples and the contri-bution of PBDD/Fs to the total TEQ was close to 100%. In the human milk samples, PBDD/Fs were detected in all samples and the average con-tribution of PBDD/Fs to the total TEQ was 40%. The results indicate that PBDD/Fs are of concern for human exposure, and should be monitored together with PCDD/Fs in future studies. Moreover, the occurrence at ac-cidental fire sites indicate that PBDD/Fs are a source for occupational ex-posure for firefighters and other professionals. The impact from PBDD/Fs on marine mammalians seems to be of less concern.
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| 2. |
- Riddell, Nicole, 1979-
(författare)
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Packed Column Supercritical Fluid Chromatography : Applications in Environmental Chemistry
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Although gas and liquid chromatography have emerged as dominant separation techniques in environmental analytical chemistry, these methods do not allow for the concurrent analysis of chemically diverse groups of persistent organic pollutants (POPs). There are also a small number of compounds which are not easily amenable to either of these traditional separation techniques. The main objective of this thesis was to address these issues by demonstrating the applicability of packed column supercritical fluid chromatography (pSFC) coupled to mass spectrometry (MS) in various aspects of environmental chemistry.First, pSFC/MS analytical methods were developed for legacy POPs (PCDDs, PCDFs, and PCBs) as well as the emerging environmental contaminant Dechlorane Plus (DP), and issues relating to the ionization of target analytes when pSFC was coupled to MS were explored. Novel APPI and APCI reagents (fluorobenzene and triethylamine) were optimized and real samples (water and soil) were analyzed to demonstrate environmental applicability.The possibility of chiral and preparative scale pSFC separations was then demonstrated through the isolation and characterization of thermally labile hexabromocyclododecane (HBCDD) stereoisomers. The analytical pSFC separation of the α-, β-, and γ-HBCDD enantiomers as well as the δ and ε meso forms was shown to be superior to results obtained using a published LC method.Finally, technical mixtures of phosphorus flame retardants (RBDPP, BPA-BDPP, and DOPO; a group of related compounds which are challenging to analyze concurrently) were examined using multiple analytical techniques and pSFC was found to be the only method which facilitated the accurate determination of the components of all 3 mixtures. This thesis confirms the potential of pSFC/MS as a fast, green, and cost effective means of separating and analyzing environmental contaminants.
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