Described in many studies as dangerous for the environment and potentially carcinogenic for humans, Chlorinated Paraffins (CPs) are easily widespread due to their substantial production and use in different products. Previous studies reported the presence of CPs in different plastic polymers. However, the impact of recycled content in plastic materials on the CPs levels hasn’t particularly been considered. Recycling plastics is becoming essential but the accumulative potential of pollutants, such as CPs, need investigations. The presence of CPs in both virgin and mixed recycled and virgin plastics was studied. Plastic pellets and plastic pieces from products made of three polymer types:Poly(methyl 2-methylpropenoate) (PMMA), Thermoplastic Rubber (TPR) and Thermoplastic Polyurethane (TPU) were analysed. A solid-liquid extraction assisted by ultrasonication was performed, followed by cleanup using silica. CPs in plastic extracts were analysed by Gas Chromatography Orbitrap High Resolution Mass Spectroscopy (GC-Orbitrap-HRMS). Because of the high volatility characteristic of long chain Chlorinated Paraffins (LCCPs), only short chain and medium chain Chlorinated Paraffins (SCCPs and MCCPs ) have been studied in this project. Interesting variations in the presence of SCCPs and MCCPs have been observed from one polymer type to another. In the results, we show that MCCPs were less frequently detected compared to SCCPs. A higher detection frequency of CPs was observed for samples containing recycled plastics. The results indicate that CPs are present in plastic polymers (TPU, PMMA and TPR) and that the content of recycled material has a direct impact on the levels of SCCPs and MCCPs.

Chlorinated paraffins (CPs) are ubiquitous environmental contaminants. They fulfill all of the criteria (persistent, toxic, and subject to long-range transport) for persistent organic pollutants (POPs) according to the United Nations Economic Commission for Europe (UNECE). CPs are also under consideration for inclusion in the Stockholm Convention on POPs. Their presence has been shown in various environmental matrices in the industrialized parts of the world, as well as in remote regions such as the Arctic. The aim of this thesis was to increase the limited knowledge of the presence of CPs in the environment, their sources to the environment, and the resulting human exposure. An analytical procedure for the determination of CPs in environmental samples based on gas chromatography coupled to electron capture detection (GC-ECD) has been developed. GC-ECD is a relatively inexpensive instrument that is fast and easy to operate. These advantages open up the possibility for a comprehensive screening of the occurrence of CPs in the environment, including developing countries. Furthermore, the occurrence of CPs in ambient air and in indoor air and dust was studied. Elevated CP concentrations in indoor air (<5-210 ng/m3) were observed compared to ambient air (0.7-33 ng/m3), which is indicative of the presence of indoor emission sources. Indoor air and dust concentrations were used to estimate the human exposure to CPs via the indoor environment. Comparison of the estimates to available dietary intake estimates indicated that the indoor exposure pathways are not negligible. CP concentrations in ambient air from urban Stockholm were higher than in rural Aspvreten, Sweden. This indicates the presence of additional (emission) sources in urban areas compared to rural sites. Additionally, a seasonal variation of air concentrations was observed at both locations, suggesting temperature dependent emission sources for CPs. These observations were supported by a substance flow analysis of CPs performed for Stockholm. This study estimated the major emission sources of CPs to the Stockholm environment to be emissions from painted surfaces and in-place sealants. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 3: Manuscript. Paper 4: Manuscript.

京都大学 / 0048 / 新制・課程博士 / 博士(社会健康医学) / 甲第19968号 / 社医博第73号 / 新制||社医||9(附属図書館) / 33064 / 京都大学大学院医学研究科社会健康医学系専攻 / (主査)教授 木原 正博, 教授 松原 和夫, 教授 中山 健夫 / 学位規則第4条第1項該当 / Doctor of Public Health / Kyoto University / DFAM

Rapid economic development has occurred during the past few decades in China with the Yangtze River Delta (YRD) area as one of the most progressive areas. The urbanization, industrialization, agricultural and aquaculture activities result in extensive production and application of chemicals. Organohalogen contaminants (OHCs) have been widely used as i.e. pesticides, flame retardants and plasticizers. They are persistent, bioaccumulative and pose a potential threat to ecosystem and human health. However, limited research has been conducted in the YRD with respect to chemicals environmental exposure. The main objective of this thesis is to investigate the contamination level, distribution pattern and sources of OHCs in the YRD. Wildlife from different habitats are used to indicate the environmental pollution situation, and evaluate selected matrices for use in long term biomonitoring to determine the environmental stress the contamination may cause. In addition, a method is developed for dicofol analysis. Moreover, a specific effort is made to introduce statistic power analysis to assist in optimal sampling design. The thesis results show extensive contamination of OHCs in wildlife in the YRD. The occurrences of high concentrations of chlorinated paraffins (CPs) are reported in wildlife, in particular in terrestrial species, (i.e. short-tailed mamushi snake and peregrine falcon). Impurities and byproducts of pentachlorophenol products, i.e. polychlorinated diphenyl ethers (PCDEs) and hydroxylated polychlorinated diphenyl ethers (OH-PCDEs) are identified and reported for the first time in eggs from black-crowned night heron and whiskered tern. High concentrations of octachlorodibenzo-p-dioxin (OCDD) are determined in these samples. The toxic equivalents (TEQs) of polychlorinated dibenzo-p-dioxin (PCDDs) and polychlorinated dibenzofurans (PCDFs) are at mean levels of 300 and 520 pg TEQ g-1lw (WHO2005 TEQ) in eggs from the two bird species, respectively. This is two orders of magnitude higher than European Union (EU) regulation limit in chicken eggs. Also, a novel pattern of polychlorinated biphenyls (PCBs) with octa- to decaCBs, contributing to as much as 20% of total PCBs therein, are reported in birds. The legacy POPs shows a common characteristic with relatively high level of organochlorine pesticides (i.e. DDT, hexacyclohexanes (HCHs) and Mirex), indicating historic applications. In contrast, rather low concentrations are shown of industrial chemicals such as PCBs and polybrominated diphenyl ethers (PBDEs). A refined and improved analytical method is developed to separate dicofol from its major decomposition compound, 4,4’-dichlorobenzophenone. Hence dicofol is possible to assess as such. Statistic power analysis demonstrates that sampling of sedentary species should be consistently spread over a larger area to monitor temporal trends of contaminants in a robust manner. The results presented in this thesis show high CPs and OCDD concentrations in wildlife. The levels and patterns of OHCs in YRD differ from other well studied areas of the world. This is likely due to the extensive production and use of chemicals in the YRD. The results strongly signal the need of research biomonitoring programs that meet the current situation of the YRD. Such programs will contribute to the management of chemicals and environment in YRD, with the potential to grow into the human health sector, and to expand to China as a whole. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 5: Submitted. Paper 6: Manuscript.</p><p> </p>