In the last decades, the rapidly growing urban population of China led to intensifying the flows of vegetables from rural to urban areas. Contamination of these vegetables with pesticides and heavy metal residues is prevalent. So far, vegetable value chain members and public regulation have achieved limited success in eliminating these chemical food safety hazards. This thesis attempts to explain the determining factors of chemical food safety hazards and to identify potential interventions that can reduce these threats.
In this thesis, I aim to address the prevalence of vegetable safety hazards in urban China. Although the food safety issue in China has been intensively investigated, earlier research lacked a thorough analysis of the distribution of food safety hazards for urban China. By reviewing previous studies, research gaps were identified in the introduction section: food safety hazards might be more prevalent in some cities, retail outlets, wholesale markets and urban districts than in others. This disparity needs to be properly measured and explained. This thesis closes this research gap by first retrieving vegetable safety data from publicly accessible sources and preparing the data for empirical analysis. Next, I applied various theoretical approaches derived from the food system framework to explain the prevalence of food safety hazards. In contrast to normative research on the legal framework or on food safety standards, I conducted an empirical analysis to explain the variations in food safety hazards distribution among different food outlets and among different locations. Through the comparative studies in this thesis, I have identified the actors that are relevant for food safety management and derived feasible policy implications.
In this thesis, I introduce and discuss cross-cutting themes with regard to the contribution of this thesis to food safety management. In China, the production of perishable vegetables is geographically concentrated in certain regions. Agricultural agglomerations can result in environmental externalities, such as soil degradation and pollution. So far, little attention has been paid to the externality effects of agricultural agglomerations on food safety. Hence, an empirical study is conducted to research the link between agricultural agglomerations, vegetable supply chains and vegetable safety hazards. Supermarketization has led to the reorganization of the vegetables provision system, through closer coordination along the supply chain and the use of secured production bases. Following the emergence of large-scale retail enterprises in developed countries in the early 20th century, the lead firms in the food retail sector in China were expected to integrate the food production and processing sectors, reorganize the food value chain, and eliminate food safety hazards. According to the value chain theory, the transition from market to hierarchy in value chain governance was expected to improve food quality and safety. However, this transition has stagnated in China a decade ago. Food safety in the hierarchical chain is still far from optimal and is unlikely to improve as many enterprises claim that they downscale or even close down their own production bases. Large-scale supermarket chains nowadays still rely on the conventional vegetable supply network consisting of numerous wholesalers. Hence, supermarkets improve vegetable safety to a limited extent only. On the other hand, the dominant role played by wholesalers in the vegetable value chain attracted me to further investigate their impact on food safety. To evaluate the renovation program, I apply the co-regulation framework to assess the implementation and results of the renovation program on the safety of vegetables. The qualitative study elaborates on the implementation of the renovation program and the behavioural changes of stakeholders in handling vegetables through interviews and field observations. The quantitative results confirm that the renovation program has a positive impact on vegetable safety. This research shows that the key factor for the success of the renovation program is the transition of authority from the local, public authority to the market management. At last, research was undertaken to evaluate the local food environment in urban China and to find out whether urban residents in China have equal access to safe and healthy food. We selected safe / contaminated vegetables and fresh / processed vegetables as two indicators to measure the local food environment. The former reflects the commitment of local government, and the latter displays the preferences of local consumers. We found that a vegetable sample is more likely to be contaminated, if it is retrieved from a township with a high population of domestic migrants than from other townships. Furthermore, processed vegetables are more prevalent in townships with more domestic migrants or rural residents than in other townships. In addition, the focus in previous research on local food environment and obesity is replaced by more context-specific concerns, which are correlated with the presence of a socio-economically vulnerable population. This study has also contributed to the research on the Hukou system by revealing the unsatisfying local food environment for domestic migrants. I expect that more studies using spatial clusters will shed further light on the increasingly complex urban food environment of mega-cities in the Global South.
I have attempted to evaluate food safety management in China with regard to the collaboration between private actors as well as between the public and the private sector. The thesis confirms that value chain members, coordination between value chain members, and public regulation are all relevant in reducing vegetable contamination. The explanation for the prevalent vegetable safety hazards lies within the organization of the food system. The thesis comes to the overall conclusion that contaminated vegetables are produced in highly intensive production areas that mainly supply to adjacent cities. A relatively high share of unsafe vegetables is distributed through small-scale, less regulated, wholesale markets and ends up in the least inspected streets and townships, where the socio-economic vulnerable population lives. This thesis highlights that the new urban migrants are the most vulnerable population in regard to food safety hazards. Moreover, new migrants and other socio-economic disadvantaged groups tend to concentrate in certain areas. Future research on the inequality in food distribution in these areas is needed and may deliver suggestions for effective interventions also in other countries.