Polychlorinated-p-dibenzo dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) (collectively termed ‘dioxins’) and polychlorinated biphenyls (PCBs) are three groups of persistent organic pollutants (POPs) ubiquitous in the environment due to their emission from numerous sources, high persistency and a propensity to be transported long distances. These compounds bioaccumulate in animal tissue, biomagnify through the food web and are toxic to humans and wildlife at relatively low concentrations. Humans may be exposed to POPs via ingestion, inhalation and dermal absorption, however, for the general population, approximately 90% of the total exposure occurs through intake of contaminated food particularly from lipid rich products, including seafood. An Australian national study highlighted that, similar to many other countries, seafood contributes a major proportion to dioxin and PCB exposure of Australians. As typical for national studies, the exposure assessment utilised contaminant concentrations in retail (sea)food and consumption information based on national dietary surveys. The risk assessment showed that the Australian population on the whole has a very low risk of exposure to dioxins through food. However, more than 80% of the Australian population lives within 50 km of the coast, where recreational, cultural and/or subsistence fishing of local seafood is prominent, potentially from areas with elevated PCDD/F and PCB concentrations. Through analysis of local seafood contamination and community seafood consumption patterns, this study assessed PCDD/F and PCB exposure for a coastal subpopulation in Moreton Bay, Queensland who consume locally caught seafood from an area with elevated PCDD/F and PCB concentrations but relatively low (background) toxic equivalency (TEQDP) in sediments, which is typical for Australian nearshore marine systems. Despite low sediment TEQDP levels, due to the dominance of octachlorodibenzo-p-dioxin (which is considered less potent compared to the most toxic 2,3,7,8-tetrachlorodibenzo-p-dioxin), elevated TEQDP concentrations were present in local seafood. In particular higher trophic fish species and some traditional seafood were found to contain TEQDP above current EU action and maximum limits. This highlights the efficiency of species specific contaminant uptake, bioaccumulation and biomagnification processes, which can result in accumulation of higher toxic dioxin and PCB congeners in biota. In contrast, concentrations of most organochlorine pesticides and flame retardants (polybrominated diphenylehters (PBDEs)) were relatively low in seafood from Moreton Bay. For fish, uptake of highly lipophilic contaminants, such as PCDD/Fs and PCBs occurs predominantly via food (biomagnification) and respiratory processes (bioconcentration) followed by selective accumulation of the more toxic, lower chlorinated 2,3,7,8 PCDD/F congeners. This study discovered that physical contact with sediment and dermal absorption of lipophilic contaminants also represents an important exposure pathway for sediment dwelling fish, resulting in higher lipid normalised PCDD/F, PCB and TEQ levels (up to 8, 5 and 3 fold) in skin compared to muscle tissue. PCDD/F and PCB congener profiles differed between muscle and skin suggesting biomagnification and skin absorption as the respective predominant uptake pathways for these tissues. Dermal uptake was estimated to contribute up to 46% to the total TEQDP load on a lipid basis in sediment dwelling fish species, thus representing an important exposure pathway, and extending the bioavailability of sediment-sorbed pollutants to the food web. Accurate determinations of lipid content and lipid TEQDP contamination within seafood samples are critical to human exposure assessments. To ensure quality assurance, different seafood extraction methods were tested to evaluate their impact on lipid yields and contaminant concentration. While levels of PCDD/Fs and PCBs on a lipid basis did not vary across the different methods employed in this study, sample preparation is a significant determinant of lipid yield from fattier fish species. If samples were freeze dried prior to extraction, 30% higher TEQDP values (on a wet weight basis) were obtained as compared to extraction using fresh sample material. Such variance in lipid results will have a significant impact on exposure assessments and should be taken into consideration during seafood contaminant analysis. The median TEQDP concentration from local seafood was approximately 25 fold higher compared to the retail seafood analysed for the national Australian risk assessment. The seafood consumption survey results from this study further indicate that coastal subpopulations consume considerably more seafood than the general population (2 to 6 times more in the present case study). This proved to be an important driver for contaminant exposure in this subpopulation. The average monthly dioxin intake for the coastal community ranged between 34 (best case) to 107 (worst case) pg TEQ kg bw-1 month1, (95th percentile: 114 - 362 pg TEQ kg bw-1 month1), an order of magnitude higher than that estimated for the general population. The contaminant exposure via the local seafood consumption pathway alone exceeded WHO tolerable daily intake levels in 11-44% of the population. These results have important implications with respect to adequate contaminant exposure assessments of Australian and other coastal subpopulations. The study outcomes highlight the importance of considering local conditions and information on contaminant fate processes for human exposure evaluations. Local seafood consumption in coastal communities can result in high exposure to PCDD/F and PCBs, even in background contamination areas. This information would be important to consider for developing future sediment quality guidelines and with respect to exposure and associated risks for coastal communities in general.

Thesis (M. Sc.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf i-ix).

Thesis (M. Sc.)--University of Hong Kong, 1990.

This thesis is intended to improve the understanding of China’s evolving export-oriented farmed seafood systems, and in particularly, shrimp and tilapia farming value chains in Southern China. An integrated, systems thinking and interdisciplinary approach in which both top–down and bottom–up approaches were combined. The research moved from system reviews, to field surveys and workshops, and then to improving sustainability by Action Research (AR), in order to form a holistic understanding of sustainability at both national and local scales. In the new millennium, the aquaculture sector has matured, and many factors now slow the growth rate of Chinese aquaculture production, such as increasing culture of high-value species and an emerging trend of extensification. There are been some strategy shifts in the aquaculture industry such as changing from a high production to high profit orientation and from causing environmental damage to ecological remediation. A key conclusion is that high growth rates, regularly used in policy dialogues, are misleading indicators and do not reflect, realistic or sustainable, growth profiles. Although overall Chinese aquaculture production is likely to further increase to meet an increasing and changing market demand, growth rates will decrease further. China already is and will continue to be a fisheries products net importer, however, if fishmeal excluded China will remain as a seafood net exporter. The status and development of four internationally-traded farmed seafood, tilapia, penaeid shrimp, macrobrachium prawns and striped catfish in China were reviewed. China is the largest producer of tilapia, penaeid shrimp and macrobrachium prawns, and striped catfish is not produced in significant quantities due to climate limitations. Meanwhile, China is the largest exporter of tilapia, the second largest exporter in the volume and third in value of shrimp in the world, while macrobrachium prawns mainly support domestic markets. Tilapia and penaeid shrimp were selected for further research. An analysis of tilapia and shrimp farm scale indicators and their relationship to farming system and market orientation, farm intensification and performance was made. Farm area, both land and water area, labour, including paid and unpaid were effective indicators to distinguish farm scale. Small-scale farms had higher land productivity in production terms but no difference in value output term, and they had much lower labour productivity than medium and large-scale farms. Farming systems were also correlated with land and labour productivities. Market orientation was closely linked to farm scale as most farms with an export orientation required registration with CIQ (China Entry-Exit Inspection and Quarantine) and were mainly large-scale. An assessment of local stakeholder sustainability perspectives along value chains revealed that more than 80% shrimp and tilapia farmers didn’t want their children to continue basing their living on aquaculture; because they considered it hard work, high risk and poorly remunerated. Farming was comparative stable with few changes in the five years prior to the survey. Major sustainability factors identified by stakeholders included input costs, profit, water availability & quality and the weather, most of which were outside their control. The measurement of these sustainability factors was firstly proposed by stakeholders and then developed to a set of sustainability indicators (SIs). Life cycle assessment (LCA) was used as evaluate the environmental performance of tilapia, pig and integrated tilapia-pig farming systems in China. Pig farming had higher environment impacts based on most impact categories than tilapia, and integrated farming systems. Sensitivity analysis showed that improvements of 5% and 10% higher feed efficiency, reduction of fishmeal in feed to 1% level and use of EU electricity could significant reduce overall environmental impacts. An action research (AR) approach was used to assess the practice of farm record keeping with farmers which were found to be generally low and a major constraint to improving product traceability increasingly demanded by consumers. Large scale and CIQ farms were more likely to keep records and for them to be detailed and analysed to inform improved management. Farmers’ motivation, ability and capability and background had significant correlation with record keeping practice. Two major dilemmas were identified by the analysis. Easy-to-use farm record-keeping system more suitable for less formally educated farmers was a clear requirement but useful storage and analysis of farm data capacity requires sophisticated management tools such as a computer system. Another dilemma is the need for coercion by regulatory authorities or encouragement through provision of education and training in increasing on-farm record-keeping to a level required for international trade and, increasingly, domestic markets. “Precision aquaculture”, value chain integrated solution, and further social-economic reforms were discussed. Finally, sustainable intensification, diversification, and extensification were proposed as strategies for China to meet the challenges of globalization and the growing demands of export and domestic value chains. In order to enhance sustainability of the sector and provide opportunities for small-scale farmers, the current status and changes of the Chinese social, economic context, food safety and environments issues were discussed. Farmers’ organizations, future consolidation, and land reforms were identified as key to the required changes of farmed seafood value chains.

In a world where the human population is increasing, new innovations to produce enough food are required. Aquaculture’s part of the global animal protein production has increased in recent years and could be a possible solution. However, if aquaculture is poorly managed, it can result in negative consequences and one such consequence is the development of antibiotic resistance. In this review, I examine how aquaculture affect antibiotic resistance by studying what the literature says on accumulation of antibiotics in different organisms and sediment, if antibiotics can be transferred to humans through consumption of antibiotic treated products, and if human pathogens in aquaculture farms may acquire antibiotic resistance. Furthermore, I examine what factors are contributing to irresponsible antibiotic use and how such use is managed. The result of this review indicate that antibiotics are able to accumulate in organisms and sediment. It is not clear however how consumption of these affect human microbiomes. In contrast, it is clear that antibiotic resistance can be transferred from antibiotic-resistant bacteria to human pathogens. Regarding antibiotic use, irresponsible use foremost exists in low-income countries and the main drivers behind such use are socioeconomic ones, such as lack of knowledge, poverty and food security. Finally, I propose possible solutions that might improve future management. / I en värld där den mänskliga befolkningen ökar krävs nya innovationer för att producera tillräckligt med mat. Vattenbrukets andel av den globala animaliska proteinproduktionen har ökat de senaste åren och kan ses som en potentiell lösning. Om vattenbruk dock hanteras ansvarslöst kan det uppstå negativa konsekvenser. En sådan konsekvens är utveckling av antibiotikaresistens hos skadliga bakterier. I denna litteraturstudie undersöker jag vattenbrukets påverkan på antibiotikaresistens genom att studera vad litteraturen säger om ackumulation av antibiotika i olika organismer och sediment, om antibiotika kan överföras till människor genom konsumtion av antibiotikabehandlade produkter, och om mänskliga patogener i vattenbruksodlingar kan förvärva antibiotikaresistens. Jag undersöker också vilka faktorer som bidrar till ansvarslös antibiotikaanvändning och hur den hanteras ur ett hållbarhetsperspektiv. Resultaten i denna studie tyder på att antibiotika kan ackumuleras i organismer och sediment men att det råder oklarheter huruvida konsumtion av antibiotikabehandlad mat påverkar mänskliga bakteriekulturer. Antibiotikaresistens kan dock överföras från antibiotikaresistenta bakterier till mänskliga patogener. Ansvarslös antibiotikaanvändning sker huvudsakligen i fattigare länder och det är förmodligen i stor utsträckning till följd av socioekonomiska faktorer som okunskap, fattigdom och livsmedelstrygghet. Slutligen föreslår jag lösningar som möjligen kan bidra till bättre hantering av framtida antibiotikaanvändning.

京都大学 / 新制・課程博士 / 博士(地球環境学) / 甲第24768号 / 地環博第240号 / 新制||地環||47(附属図書館) / 京都大学大学院地球環境学舎環境マネジメント専攻 / (主査)准教授 浅利 美鈴, 講師 BAARS ROGER CLOUD, 教授 宇佐美 誠 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM

published_or_final_version / Urban Planning / Master / Master of Science in Urban Planning

Responsible Sourcing is gaining growing importance for companies willing to demonstrate responsibility and commitment to sustainable practices. Sourcing is a key element of supply chain management and by adopting responsible sourcing practices, companies can greatly contribute to the sustainability of their entire supply chains. Being close to both customers and suppliers, retailers hold a particularly influential position in the supply chain and their sourcing choices can play a key role for sustainability improvements. This paper investigates the different strategies that can be adopted to guarantee responsible sourcing in the retail sector, through the specific case study of two UK retailers, Sainsbury´s and Tesco, and their offer of sustainable seafood. Specifically, the relation between the offer of MSC certified products and the retailers´ commitment to source responsibly is here analysed. The main source of data collection is a content analysis of retailers´ CSR online reports and web pages. Additional information is obtained through reports and web pages’ analysis of four UK organizations dealing with sustainable seafood issues. The findings of the study suggest that the offer of MSC certified products is positively correlated with the adoption of responsible sourcing practices; different strategies are available to retailers to guarantee responsible sourcing and that retailers´ sourcing policies can be influenced by other stakeholders´ guidelines for responsible sourcing.

Aquaculture and fisheries hold promise for supplying a growing world population with healthy food produced without undermining the earth’s carrying capacity. However, just as livestock production and agriculture, seafood production can have negative environmental impacts and if a continuous or even increased supply is to be guaranteed, the pressure on affected ecosystems needs to be limited. Due in part to a perceived failure of other governance mechanisms in improving the environmental performance of the sector, a large number of voluntary market based standards for farmed and wild caught seafood have been developed. Nonetheless, the knowledge base on the extent to which implementation leads to environmental improvements remains limited. Moreover, the role of consumers in driving demand for eco-labeled seafood is presently an under-researched area. This thesis aims at reducing this knowledge gap through an examination of the potential environmental effectiveness of aquaculture eco-certification and internal, psychological variables predicted to be of importance for sustainable seafood consumption. Put differently, what is the potential of eco-certification in greening the blue revolution and fuel ‘turquoise growth’, and how can consumer demand be spurred? In Paper I, the role of eco-certification in improving the growing aquaculture sector at large was explored. Results showed that environmental effects at global scale likely will be limited due to e.g. partial coverage of species groups and environmental impacts, and a lack of focus on Asian markets and consumers. In Paper II the environmental performance of eco-certified and non-certified mangrove-integrated shrimp farms in Vietnam was compared by using Life Cycle Assessment and put in relation to conventional, more intensive farms. While there was no substantial difference between certified and non-certified farms in terms of environmental impacts, emissions of greenhouse gasses were higher for mangrove-integrated than conventional farms due to mangrove land use change. The results from Paper III demonstrated that the body of literature investigating ecological effects of seafood eco-certification is limited. ‘Spatially explicit ecosystem service information’ (ES-information) on e.g. key ecosystem services and biodiversity in a given area is suggested to have potential to improve sustainability standards. Taking guidance from the pro-environmental behavior literature, consumers in Stockholm, Sweden were consulted on awareness of and attitudes towards eco-labeled seafood (Paper IV-V). Two variables, concern for environmental impacts and knowledge about seafood eco-labels were the best predictors for stated eco-labeled seafood purchasing. Moreover, there seemed to be a misalignment between consumers’ expectations on eco-labeled food in general and certification requirements for eco-labeled seafood. From this set of findings, a number of improvements of current seafood eco-certification are suggested. First, include an LCA-perspective in standards to a higher degree than presently done and provide readily available ES-information in the implementation and evaluation phase of certification. Second, introduce standardized mechanisms for capturing potential environmental improvements over time. And finally, stimulate demand by targeting Asian consumers and markets as well as strengthen consumer eco-label awareness and emotional involvement. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 5: Manuscript.</p><p> </p>

Oyster tongers are a cultural icon of Florida's maritime heritage and geography. Challenged for generations by the vagaries of weather, including catastrophic storms and years-long droughts, and economic uncertainties this maritime heritage is fading fast. While Florida's north and west coasts produce 90 percent of the Florida oyster harvest and ten percent of oysters consumed in the United States, the industry is at risk today for reasons including a declining demand for Florida oysters because of health concerns; water pollution; population growth and its accompanying development of condominiums, gated communities, and retail shopping centers; and declining interest in the hard work of oystering as a livelihood. This work investigates those challenges to Florida's Gulf Coast oyster industry through the lens of a twenty-first century consumer. I examine why the U.S. Department of Agriculture considers raw oysters a significant challenge to public health and how local, state, and federal government regulations, along with cooperative efforts of the seafood industry, offset the potential for oysters to convey foodborne illness to human consumers. The fact that raw oysters carry a high propensity for conveying bacterial disease makes them a unique marketing challenge, especially outside of months that have an r in them. As a subject of culinary tourism, Florida oystering maintains an iconic maritime heritage. The labor force of the commercial oystering business has ranged widely-from migrant mothers working with toddlers at their side and their school-age children forgoing education for shucking oysters at the turn of the twentieth century to a new, Hispanic work force whose strong work ethic heartily satisfies oyster processors as local interest for the hard work in the industry declines. The threat to sustainability of both the working traditions of the Apalachicola oyster folk, and the oysters themselves as a bountiful resource, grows in direct proportion to the environmental pressures fostered by rapid and poorly-regulated population growth. A legitimate question might be, given the difficulties of the work and challenges to the industry, is it worth the state's effort to help sustain this industry?