Determining accurate exposure estimates and subsequent risk of hydrophobic organic contaminants (HOCs) in aquatic sediments requires measuring the bioavailable and/or bioaccessible concentration in sediment; as total extractable concentrations have not been found to produce accurate results. Organic carbon normalization was originally proposed as a means of accounting for the bioavailable concentration by estimating the chemical activity of the contaminant expressed as the freely dissolved chemical concentration in the interstitial water, thus correcting exhaustive extractable concentrations for the sorbing phase of sediments. Organic carbon normalization often fails, however, to accurately reflect exposure as other environmental variables (i.e. organic carbon composition, aging time of contaminants in the environment) alter desorption, such that changes in chemical activity as represented by the interstitial water concentrations are not controlled by organic carbon alone. Desorption-based samplers, such as single-point Tenax extractions (SPTE), provide a clearer estimate of bioaccessibility than organic carbon normalization by serving as a sink for desorbing compound for the length of the extraction. In this way, SPTEs account for all the factors affecting desorption and the resulting interstitial water concentrations, providing estimates of the chemical concentration that will become available for exposure in a given time frame. The utility of SPTEs as an exposure metric has been demonstrated many times in the literature through estimates of bioaccumulation and development of toxicity benchmarks. The simplicity, accuracy, and robust nature of this technique suggests this tool could serve as an ideal means of evaluating exposure and risk of HOCs, and more specifically acutely toxic compounds, such as pyrethroids, during environmental sampling and risk assessments of aquatic sediments. However, the use of this method is limited within the scientific literature and absent from most risk assessment protocols. The reasons for its limited use are linked to poor methodological standardization, an absence of understanding of environmental and methodological variation on estimates of bioaccessibility provided by SPTEs, and only a vague idea of how Tenax extractions relate to other exposure metrics, such as passive samplers. Therefore, the dissertation goals were to: evaluate the effects of variation in the SPTE, specifically the Tenax mass to organic carbon mass (Tenax:OC) ratio, on exposure estimates of pyrethroids (Chapter Two); understand how methodological and environmental variation affect the relation of SPTEs to bioaccessibility represented by desorption of pyrethroids from the labile desorbing fraction (Frap) (Chapter Three); and, determine how bioavailability and bioaccessibility are linked through evaluation of chemical activity expressed as the freely dissolved chemical concentrations provided by SPTEs, passive sampler concentrations, and Frap (Chapter Four). The most variable aspect of the SPTE within the Tenax literature is the Tenax:OC ratio used during 24 h SPTEs. Yet, no study has evaluated how altering this ratio may affect 24 h SPTE concentrations and thus, biological exposure estimates provided by Tenax extractions. Manipulating the Tenax:OC ratio used during 24 h SPTEs of pyrethroids from laboratory-spiked and field-contaminated sediments revealed the effect of this variation was such that Tenax extractable pyrethroid concentrations varied between 0.85 to 3.91-fold between the highest and lowest ratios examined. The results of this experiment suggest most of the variation in toxicological endpoints derived using Tenax extractable concentrations is due to toxicokinetic and toxicodynamic variation in biological responses across sediments and not due to methodological variation of the Tenax extraction (Chapter Two). The utility of the SPTEs as an estimate of exposure is linked to the ability of SPTEs to reflect the chemical concentration that desorbs from sediment. As many factors, such as the organic carbon content, aging time of sediments, and hydrophobicity of the compounds, can impact desorption, understanding how these factors affect the relationship of SPTEs to biological exposure is needed to evaluate the consistency of the Tenax extraction. The relation of SPTE concentrations to Frap was proportional despite changes in organic carbon content of the sediment being extracted, the hydrophobicity of the pyrethroids, or the Tenax mass used during the extraction, such that the SPTE concentration was equal to 1.46 ± 0.03 times the pyrethroid concentration in Frap (Chapter Three). Only the aging time of the pyrethroids in the sediment significantly affected this relationship, as desorption from longer aged sediments slowed, reducing the 24 h SPTE concentration to Frap ratio by -0.0027/d (Chapter Three). The results of Chapters Two and Three demonstrate the consistency of the Tenax extraction as a representation of biological exposure of pyrethroids in sediment. However, other aspects limit the widespread use of the Tenax method, particularly the relation of this technique to more widely accepted bioavailability-based metrics, such as passives samplers. Tenax extractions are often disregarded in favor of passive samplers as the link between bioavailability-based metrics, chemical activity, and exposure is well understood. However, as SPTEs and passive samplers both demonstrate a clear relation to bioaccessibility through estimates of Frap, it was hypothesized that both exposure metrics represent the same chemical fraction of sediment, and as such could be considered complementary tools for evaluating biological exposure through estimates of the freely dissolved interstitial water concentration. This was confirmed when comparisons of the chemical activity expressed as the interstitial water concentration at equilibrium were done using the chemical concentration estimated by Frap, a passive sampler, and SPTEs. Strong linear relationships (p<0.0001) were found among all three metrics, such that Frap, passive sampler, or 24 h SPTE concentrations of pyrethroids from sediment provide comparable estimates of the freely dissolved interstitial water concentration in sediment. Thus, Tenax extractions and passive samplers, which describe the bioaccessible and bioavailable concentrations, respectively, describe the same chemical fraction in sediment; the labile desorbing fraction. This dissertation provides further concrete evidence that the SPTE offers a robust, rapid, and cost-effective means of evaluating exposure of acutely toxic compounds in sediment. With data that link this exposure metric to more widely accepted methods, such as passive samplers, and demonstrate the robust character of the SPTE, the research presented here should further the use of the SPTE within the scientific and risk assessment communities.

The adoption of children in care who are legally referred to as “looked after”, (Children Act 1989, s22, HMSO, 1989) usually by local authorities is a key national Government objective (DfE, 2016a) where rehabilitation with the birth family is not viable. The desire to place more "looked after" children for adoption with greater speed is not new. It became increasingly apparent after the election of the New Labour Government in 1997 due to concerns about drift and delay in planning for children in care (DoH, 2000a) leading to poorer outcomes. This led to a series of measures aimed at increasing the use and speed of adoption. Eventually this resulted in the introduction of the Adoption and Children Act 2002 (HMSO, 2002) that also for the first time in English law recognised that the welfare of the child is of paramount concern when considering adoption. There is an abundance of published literature that considers the topic of adoption. However, there is a dearth of studies that have comprehensively considered the journey that adopters undertake to become parents. This practice based study was conducted by a researcher who is a senior academic manager and an active social work practitioner with extensive professional experience of adoption. A unique aspect of the study is the longitudinal mixed methods approach used to gather data in real time from a sample of adopters. The three part study tracks the journeys of the sample of adopters from when their application to adopt had been accepted by an adoption agency until after children were placed. The study was supported by five adoption agencies based in England. The data was collected over a period of two years from the adopters who described their experiences and perceptions of their journeys in real time. The information from the adopters is triangulated with data from adoption professionals from the agencies that supported the study. The professionals discussed their approaches to the adoption process, as well as their own experiences of working with adopters. The longitudinal nature of the study enables an analysis of how and why adopters’ experiences and perceptions changed over time. The research considered the changing power dynamics between adopters and professionals during the different stages of the journey to adopt. Furthermore, the long-term impact of professional interactions with adopters during the adoption process are discussed.

Introduction: Poor insight is included as a risk factor for violence in risk assessment tools such as the Historical Clinical Risk-Management-20 version 3 (HCR-20v3) yet there is a lack of consensus around the relationship between poor insight and violence in individuals with psychosis. A systematic literature review was therefore carried out to clarify this relationship. Relatedly, a research project aimed to outline the predictive validity of the HCR-20v3 total and sub-scale scores to violence in forensic inpatients. A secondary aim was to understand the predictive ability of 2 dynamic risk factors within the HCR-20v3 clinical sub-scale; insight and positive symptoms, alongside age and history of violence in relation to violence in psychosis. Method: A systematic search of studies investigating insight and violence in patients with psychosis, published between 1980 and 2016 was carried out on relevant databases.17 articles from combined search results of 5694, met the inclusion criteria. These were selected for full-text review and quality grading which was subject to inter-rater reliability. In the research project, the predictive validity of the HCR-20v3 to violence was assessed in N=167 forensic inpatients. A sub-sample of N=135 was then used to investigate insight, positive symptoms, age and history of violence in relation to violence. Data was extracted from case files, with the exception of violence data which was collected prospectively from date of HCR-20v3 publication via DATIX. Results: The systematic review found 8 studies in support of a positive relationship between poor insight and violence, whilst 9 studies did not support this relationship. The majority of better quality studies measured the clinical insight dimension which tended to demonstrate a positive relationship between poor insight and violence. Methodological limitations were apparent across studies. The research project found HCR-20v3 total and clinical and risk-management sub-scale scores to predict violence. The clinical sub-scale was the strongest predictor of violence and physical violence specifically. Sub-sample analysis found positive symptoms and history of violence to significantly predict violence generally whilst only positive symptoms demonstrated prediction of physical violence. Insight and age were not significantly associated with either violence type. Discussion: The systematic review found partial support for a positive relationship between poor insight and violence in psychosis. Future good quality research is required to develop a fuller understanding of this issue. Research project results support the use of the HCR-20v3 in the risk assessment and management of forensic inpatients. They reinforce the usefulness of dynamic risk factors within the clinical sub-scale in particular. In line with the majority of studies within the systematic review however, a relationship between insight and violence in a sub-sample of patients with psychosis was not found. Recommendations are made for the regular re-assessment of dynamic risk factors within the HCR-20v3 clinical sub-scale in order to support patients to reduce their level of risk, with the caveat that future research is still required to support a relationship between insight and violence in this patient group.

abstract: Over the last few decades, specialized courts have received an increasing amount of research attention. The existing literature mostly supports drug courts and demonstrates their effectiveness in reducing recidivism and substance abuse, more generally (Belenko, 1998; Bouffard & Richardson, 2007; Gottfredson, Najaka, & Kearley, 2003). Whether the drug court model “works” across offender subgroups remains an open empirical question. The current study uses data originally collected by Rossman and colleagues (2003-2009) for the Multi-Site Adult Drug Court Evaluation (MADCE) to examine the effect of drug court participation on recidivism among unique offender subgroups. First, a context-specific risk score is used to examine recidivism outcomes. Second, offender subgroups are statistically created using latent class analysis (LCA). Recidivism outcomes are then assessed by subgroup, with these results compared to the initial measure of risk. Both analyses are performed using the full sample of drug court participants and the comparison groups. Finally, the third model uses a split sample analysis by court participation to explore the full effects of drug court. The findings of the present study contribute to the theoretical literature and help inform future policy regarding risk assessment and the treatment of offenders in drug courts. / Dissertation/Thesis / Masters Thesis Criminology and Criminal Justice 2018

Master of Science / Department of Geology / Saugata Datta / Children are the demographic most susceptible to and affected by lead poisoning. Lead contamination in soil has been recorded as being primarily from lead-based paint, historic leaded gasoline emissions, and from lead point-source emitters. The highest risk of elevated blood lead level (BLL) is correlated with living in an area dominated by pre-1950’s housing. From 1976 to 1994, midst the phasing out and removal of lead from gasoline, the blood lead levels of children in the United States decreased from 16 µg/dL to 3.2 µg/dL. There is evidence showing the irreversible effects of intellectual impairment still occur at levels of BLL below 10 µg/dL. In Kansas, Barton and Ellis counties residential soils were sampled, and chemical composition was examined with a handheld XRF and an HR ICP-MS. Particle size and pH were recorded for all samples. The presence or lack of of lead sulfate and lead carbonate was identified using XRD. Chemical tests revealed elevated Zn and As with increasing Pb concentrations. There was weak evidence of lead sulfate in one of eight tested samples. Barton county has courser sediments and the top five highest Pb concentrations recorded in this study. There is a significant correlation with Pb concentrations and age of housing for houses built prior to1950. Pb Isotopic analysis on eight samples showed multi-source contamination in the soil. We believe the source of most of the lead is from ambient lead mixed with historic leaded gasoline deposits and possible output from factories/coal, along with leaded paint in older homes. Three of the eight samples had paint chips which tested positive for lead. Maps were created showing central Kansas having elevated blood lead levels in children and overlays were made illustrating oil well density in counties. Five variables were used to create a risk assessment map for Kansas: housing age, poverty levels, blood lead levels, number of oil wells, and population.

The persistent organic pollutants (POPs) refer to many different chemicals that, upon release into the environment, remain intact for several decades. These contaminants travel long distances through repeated cycles of deposition and evaporation, and eventually deposit in the Arctic regions. The purpose of this work was to examine the potential human health implications of POP exposures among the Canadian Inuit, using modelling and epidemiological approaches. Blood guideline values were developed for the organochlorine pesticides, chlordane and toxaphene, and the polychlorinated biphenyls (PCBs) using the concept of biomonitoring equivalents (BEs), which are based on toxicity endpoints and toxicokinetic modelling to convert an oral reference dose to an equivalent blood concentration. The biomonitoring data from the Adult Inuit Health Survey (2007-2008) and the Canadian Health Measures Survey (CHMS, Cycle 1 2007-2009) were compared with the derived guideline values to assess population-level risks of exposures for the Inuit and the general Canadian population, respectively. Epidemiological analyses were also conducted to explore if POPs were associated with diabetes and high cholesterol, using data from the Inuit Health Survey. A set of BE values were derived for chlordane isomers and metabolite, three abundant toxaphene isomers, and the PCBs. The derived values are in a similar range of the BEs of other POPs in the literature. Among the Inuit, a large percentage exceeded the trans-nonachlor guideline value, particularly among the elderly. Fewer exceedances were observed for cis-nonachlor and oxychlordane, none for toxaphene, and minimally for the PCBs. In comparison, no exceedances for any of the POPs were observed in the general Canadian population. Highest vs. lowest quartile exposures to PCBs and p,p’-DDE were associated with increased risk of diabetes and an increase in fasting glucose among the Inuit. In addition, PCBs were associated with increased risk of high cholesterol, and higher levels of serum triglycerides, total cholesterol, and low-density lipoprotein cholesterol (LDL-C), but not high-density lipoprotein cholesterol (HDL-C). The results of this work suggest that exposures to POPs remain a potential health concern among the Canadian Inuit. Future research efforts should be devoted to collecting updated contaminant concentrations for the Inuit, measuring contaminants in prepared food samples, conducting cohort studies on contaminant exposures and health outcomes, and assessing the effects of chemical mixtures using statistical approaches and toxicokinetic modelling.

Made available in DSpace on 2014-10-09T12:27:43Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:13Z (GMT). No. of bitstreams: 0 / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Made available in DSpace on 2014-10-09T12:27:43Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:13Z (GMT). No. of bitstreams: 0 / A crescente preocupação com o nível de risco associado ao transporte de materiais perigosos levou várias instituições internacionais a empenhar esforços na avaliação de risco em nível regional. Seguindo essa tendência, o objetivo deste trabalho foi analisar os mais recentes processos de análise de riscos decorrentes do transporte rodoviário de materiais perigosos. No presente trabalho foram avaliadas 21 metodologias de análise de riscos, desenvolvidas por vários autores e para diversas localidades. Em especial, duas foram revistas e discutidas: um método recentemente desenvolvido pelo Instituto Federal Suíço de Tecnologia (Nicolet-Monnier e Gheorghe, 1996) e a estratégia delineada pelo Center for Chemical Process Safety - CCPS (1995), levando em consideração a estimativa do risco individual e social. Também foram aplicados os modelos de Harwood et al. (1990) e de Ramos (1997), adaptados por Hartman (2003) à realidade das estradas do Estado de São Paulo. A extensão dessas metodologias foi explorada, a fim de encontrar as suas vantagens e desvantagens. Como estudo de caso o presente trabalho considerou o transporte de amônia ao longo de duas rotas possíveis por rodovias do Estado de São Paulo, incluindo uma parcela significativa de avaliação em área densamente povoada, obtendo-se os resultados utilizando uma das metodologias de analise de risco. A inovação proposta por esse trabalho foi a pesquisa, o desenvolvimento e a introdução de duas variáveis ao modelo proposto por Harwood et al. (1990). Essas variáveis ponderadoras no valor do risco foram: a idade do condutor e a zona de impacto conforme o período do dia em que o transporte foi realizado em função do volume do produto transportado. As alterações propostas têm como objetivo deixar o valor do risco mais sensível em relação ao tipo do produto transportado e a idade do condutor. As principais etapas processuais relacionadas com a análise quantitativa dos riscos para sistemas de transporte são suportadas pelos métodos precedentes para instalações fixas. Especial atenção foi dada à forma de coletar informações locais e para estimar coeficientes que refletissem as condições prevalecentes na região considerada no estudo de caso apresentado. / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Abstract The aim of this study was to assess a series of caries risk indicators to find a suitable model for screening adolescents for risk cases, and to evaluate the long-term efficacy and cost-effectiveness of an one-year intervention programme provided for the resulting risk groups. To reduce the spread of infectious diseases at 20 day-care centres, risk factors for the occurrence of salivary mutans streptococci were surveyed in 345 children before and after 8 months of intervention, i.e. withdrawal of tooth brushing in 10 centres. Dental health habits were evaluated by means of questionnaires. Four clinical and six salivary tests were related to 11-month caries increment in 181 adolescents. The 109 high-risk subjects presenting four or more risk factors were provided either with chlorhexidine or fluoride treatment, the low-risk group receiving basic prevention. An age and sex-matched control group was chosen. Life-long data on all 390 subjects were collected from their dental records. Survival analysis was applied, taking as the starting point the time of tooth eruption and as the event the first filling due to caries. The costs of the intervention and the number of fillings were compared between the groups. The dental health of the risk groups tended to approach the average level for the control group. One tooth surface per subject was saved from filling. The costs of fillings for the control group were twice as great as those for the risk groups at the end of the intervention, but only slightly more after the five-year follow-up period. The model (DFS, Candida and sucrase) offers additive information for finding adolescents at risk of caries, and for targeting preventive measures at the individual level and for the motivation of patients. The results stress the importance of dental age and of providing preventive procedures at the time of tooth eruption. The present risk-based strategy proved to be of moderate benefit to dental health by comparison with the costs of normal preventive and restorative care and cannot be recommended as such for a target population with a high risk of caries.

In conjunction with horizontal drilling, hydraulic fracturing or fracking has enabled the recovery of natural gas from low permeable shale formations. In addition to water, these fracking fluids employ proppants and up to 38 different chemical additives to improve the efficiency of the process. One important class of additives used in hydraulic fracturing is biocides. When applied appropriately, they limit the growth of harmful microorganisms within the well, saving energy producers 4.5 billion dollars each year. However, biocides or their harmful daughter products may return to the surface in produced water, which must then be appropriately stored, treated and disposed of. Little is known about the effect of mineral-fluid interactions on the fate of the biocides employed in hydraulic fracturing. In this study, we employed laboratory experiments to determine changes in the persistence and products of these biocides under controlled environments. While many minerals are present in shale formations, pyrite, FeS2(s) is particularly interesting because of its prevalence and reactivity. The FeII groups on the face of pyrite may be oxidized to form FeIII phases. Both of these surfaces have been shown to be reactive with organic compounds. Chlorinated compounds undergo redox reactions at the pyrite-fluid interface, and sulfur-containing compounds undergo exceptionally strong sorption to both pristine and oxidized pyrite. This mineral may significantly influence the degradation of biocides in the Marcellus Shale. Thus, the overall goal of this study was to understand the effect of pyrite on biocide reactivity in hydraulic fracturing, focusing on the influence of pyrite on specific functional groups. The first specific objective was to demonstrate the effect of pyrite and pyrite reaction products on the degradation of the bromine-containing biocide, DBNPA. On the addition of pyrite to DBNPA, degradation rates of the doubly brominated compound were found to increase significantly. DBNPA is proposed to undergo redox reactions with the pyrite surface, accepting two-electrons from pyrite, and thus becoming reduced. The primary product is the monobrominated analogue of DBNPA, 2-monobromo-3-nitrilopropionamide (or MBNPA). The surface area-normalized first-order initial degradation rate constant was found to be 5.1 L.m-2day-1. It was also determined that the dissolution and oxidation products of pyrite, FeII, S2O32- and SO42- are unlikely to contribute to the reduction of the biocide. Taken together, the results illustrate that a surface reaction with pyrite has the ability to reduce the persistence of DBNPA, and as a consequence change the distribution of its reaction products. The second objective was to quantify the influence of water chemistry and interactions with pyrite on the degradation of the sulfur-containing biocide. Dazomet readily hydrolyzes in water due to the nucleophilic attack of hydroxide (OH-) anions. Thus the half-life of dazomet during the shut-in phase of hydraulic fracturing will decrease with increasing pH: 8.5 hours at pH 4.1 to 3.4 hours at pH 8.2.Dazomet degradation was rapidly accelerated upon exposure to the oxidized pyrite surface, reacting five times faster than hydrolysis in the absence of pyrite at a similar pH. The products measured were identical to those identified on hydrolysis (methyl isothiocyanate and formaldehyde) and no dissolved iron was detected in solutions. This suggests that the dithiocarbamate group in dazomet was able to chemisorb onto the oxidized pyrite surface, shifting the electron density of the molecule which resulted in accelerated hydrolysis of the biocide. The third objective explored the reactivity of various biocide functional groups due to the addition of pyrite. Several elimination mechanisms were identified, and tied to the reactivity of the specific functional group involved. The addition of pyrite led to accelerated degradation of dibromodicyanobutane. This is because the bromine (-Br) group is easily reduced. For methylene bis(thiocyanate), hydrolysis was a noteworthy elimination mechanism since the thiocyanate (-SCN) functionality is a good leaving group. Benzisothiazolinone and methyl isothiazolinone were stable at low pH due to the stabilizing donor-acceptor interactions between the organic biocides’ carbonyl (–C=O) groups and salts in the solution. This body of work has illustrated that pristine pyrite can undergo redox reactions with brominated biocides used in hydraulic fracturing, reducing their persistence and altering the product distribution. This will change the efficacy and the risks associated with the use of these biocides in shales containing pyrite, particularly at lower pH where organic compounds are more stable to hydrolysis. However, at higher pH hydrolysis becomes more important, and additional studies will need to be conducted to investigate the pyrite contribution under these conditions. Conversely, the FeIII surface groups on oxidized pyrite can catalyze the hydrolysis of dazomet and may do so for other labile, sulfur-containing biocides as well. Overall, this research has shown that the physicochemical properties (such as the acid dissociation constant and the standard reduction potential) that govern the environmental reactivity of a molecule can be used to anticipate its reactivity in hydraulic fracturing.