
by Nilanjana Ganguli , Anna Maria Subic, Janani Maheswaran and Byomkesh Talukder
Abstract: Urban agriculture is gaining recognition for its potential contributions to environmental resilience and climate change adaptation, providing advantages such as urban greening, reduced heat island effects, and decreased air pollution. Moreover, it indirectly supports communities during weather events and natural disasters, ensuring food security and fostering community cohesion. However, concerns about planetary health risks persist in highly urbanized and climate-affected areas. Employing electronic databases such as Web of Science and PubMed and adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we identified 55 relevant papers to comprehend the planetary health risks associated with urban agriculture. The literature review identified five distinct health risks related to urban agriculture: (1) trace metal risks in urban farms; (2) health risks associated with wastewater irrigation; (3) zoonotic risks; (4) other health risks; and (5) social and economic risks. The study highlights that urban agriculture, while emphasizing environmental benefits, particularly raises concerns about trace metal bioaccumulation in soil and vegetables, posing health risks for populations. Other well studied risks included wastewater irrigation and backyard livestock farming. The main limitations in the available literature were in studying infectious diseases and antibiotic resistance associated with urban agriculture.
1. Introduction
Urban agriculture is a dynamic concept encompassing agricultural activities within urban areas, in contrast to traditional rural farming settings. This term covers various practices, including horticulture, crop cultivation, animal husbandry, forestry, agroforestry, and aquaculture1, 2, 3 Various terms like urban farming, community gardening, and rooftop farming are associated with this phenomenon. Urban agriculture constitutes a diverse array of systems and practices that vary based on the locations and socioeconomic backgrounds of those involved.4
Urban agriculture is an ancient practice, with some of the earliest evidence dating back to 3500 before the Common Era in Mesopotamia, where small farm plots existed within city walls.5 While its history is diverse and longstanding, urban agriculture has gained significant popularity on a global scale in recent times. The United Nations started showing heightened interest in urban agriculture in the early 1980s, and it has since become a prominent topic of global discussion as a sustainable solution for fostering green urban growth and climate adaptation.6,7
Numerous international organizations, including the United States Department of Agriculture, the International Development Research Centre, the Food and Agriculture Organization of the United Nations, and the European Federation of City Farms, have actively promoted urban agriculture as a means to support growing populations and enhance sustainability. Particularly in the Global North, there is a growing concern about the industrial food chain supplying grocery stores, leading to increased interest in local and regional food systems and contributing to the upsurge of urban agriculture.7 Urban agriculture is also being increasingly utilized in the Global South to enhance food security and meet nutritional requirements.8
The global population is multiplying, particularly in urban and metropolitan regions. It is estimated that around 68 % of the projected 9.7 billion people will be residing in urban areas by 2050.9 However, many urban residents, especially in the Global South, face malnutrition, poverty, and food insecurity. Urban agriculture is vital in addressing these pressing issues.10,11
In literature, urban agriculture is widely recognized for its diverse benefits, encompassing social, cultural, health, wellbeing, food security, environmental sustainability, and economic aspects (see Table 1).10,12, 13, 14, 15, 16, 17, 18, 19. Scholars increasingly focus on urban agriculture, investigating trends such as sustainability, nature-based solutions, the water-energy-food nexus, and technological innovations to enhance its sustainability.20,21

Urban agriculture offers a potential solution for food security and planetary health, particularly in underserved communities, 22, 23, 24 by providing fresh, nutrient-rich, locally grown food that addresses malnutrition-related issues like stunting and underweight. 25, 26, 27, 28, 29 These solutions especially benefit low- and middle-income countries (LMIC) experiencing rapid urban growth and complex challenges like food insecurity and poverty. Its positive impact extends to influencing BMI scores and reducing obesity risk23,30,31 through encouraging lifestyle changes and physical activity in urban dwellers.32
Moreover, urban agriculture contributes to environmental resilience and climate change adaptation by promoting urban greening and reducing the urban heat island effect33,34 by cutting food miles,35 reducing air pollution, supporting biodiversity, and facilitating groundwater recharge through increased rainwater absorption.36 Additionally, urban agriculture indirectly aids communities in responding to weather events and natural disasters like flooding, windstorms,33 and earthquakes, providing food security and fostering a sense of safety and community support.34 Engaging with urban gardens inspires pro-environmental behavioral changes, promoting sustainable growth and consumption decisions,37,38 creating aesthetically appealing environments, and fostering emotional connections.39
Urban agriculture is receiving promotion and support from United Nations organizations like Milan Urban Food Policy Pact.40 However, among scholars and policymakers, there is growing concern about the potential short-term and long-term planetary health (interconnectedness between humans and ecosystems health) issues and unintended consequences of urban agriculture, especially in highly urbanized and climate-change-affected environments. To address this concern, this paper seeks to identify and examine the health risks associated with urban agriculture in such settings. Our study intends to raise awareness within and beyond academia about the significance of adopting a critical lens to analyzing urban agriculture as a tool for sustainable development, as well as to present a thorough list of the benefits and risks of the practice in a global context.
2. Methodology
In order to achieve the study's objectives, the first step involved creating databases of the relevant literature. Subsequently, objective-focused data were extracted from these databases.
2.1. Database creation
A systematic literature review, adhering to Prisma guidelines, was conducted to build a comprehensive database for the study. A predefined research protocol was formulated: identifying articles, screening for eligibility using well-defined inclusion and exclusion criteria, and subsequent data extraction.
In May 2021, a comprehensive search for peer-reviewed articles was conducted using the Web of Science and PubMed electronic databases. These databases were chosen for their user-friendly interface, diverse data exporting options, and researcher preference. The search aimed to capture many articles on the intersection of health and urban agriculture. Various keywords were employed to achieve this, encompassing different aspects of urban agriculture, such as community gardens, rooftop farming, and backyard farming (Table 2). The search was limited to English-language articles published from 2010 onwards.

2.2. Data extraction
During the screening phase, the initial step involved exporting the search results to the reference manager Zotero to identify and eliminate duplicate articles. The studies underwent title and abstract screening, applying the predefined inclusion and exclusion criteria. Research articles utilizing primary or secondary data were considered for inclusion, while review articles and those discussing peri‑urban agriculture were excluded. To be included, the studies needed to focus on urban agriculture and present a substantial discussion on its relationship with human health. Articles lacking a clear focus on the connection between urban agriculture and human health were excluded from the analysis.
The search yielded 678 articles from the Web of Science and 439 articles from PubMed, resulting in 846 articles after eliminating duplicates. This number was reduced to 351 articles following title screening and further narrowed to 139 articles after abstract screening. Finally, 55 articles were identified and included in the data extraction process (see Fig. 1). In addition to the selected 55 articles, 52 other articles were identified through a manual hand search to support the manuscript.

During data extraction, systems thinking was applied. Systems thinking is a comprehensive analytical approach that emphasizes understanding the interconnectedness of individual components within a system and their interactions over time. It also considers the system's position within more extensive, more complex systems.
Two researchers conducted data extraction using Microsoft Excel, with each assigned a specific set of articles for extracting data. The key variables extracted included: (1) the study's location; (2) the researcher's affiliation; (3) social, environmental, or economic benefits; (4) social, environmental, or economic risks; (5) exposure pathways; and (6) direct and indirect impacts on human health. During data extraction, systems thinking guided identifying and extracting key variables using Microsoft Excel. This approach aimed to capture individual components and their dynamic interactions and relationships. Each researcher involved in the data extraction process was assigned a specific set of articles, ensuring a thorough and consistent examination of the interconnected aspects within the urban agriculture system.
3. Results
The results showcase the trend of studies of urban agriculture, a comparative analysis of research interest between risks and benefits, global participation in urban agricultural research, the various types of research conducted, and a bibliometric analysis of the planetary health risks associated with urban agriculture based on the analysis of 55 selected articles.
3.1. Trends, global participation, and risks vs. benefits of urban agriculture studies
Urban agriculture has received much attention in academic research over the last decade, and its growth has been particularly significant since 2015. However, much of urban agriculture research has been led by the Global North (n = 43), with only 22% of all our articles in our sample showing a collaboration between scholars from the Global North and South.
Although it was encouraging to find that significant research had been conducted to identify risks associated with urban agriculture (n = 39), the scope of investigation remained limited, with 51% of the risk-related articles (n = 20) in our sample focusing on trace metal contamination. Another interesting finding from this study was the difference in categorical prominence between benefits and risks, with social benefits (n = 26) dominating the benefits category and environmental risks (n = 30) dominating the risk category.
3.2. Planetary health concerns
Despite the evident benefits of urban agriculture, it is necessary to understand the various risks that can arise from urban gardening to address and avoid unintended short-term and long-term planetary health issues. The concept of planetary health recognizes that human activities, such as deforestation, pollution, climate change, habitat destruction, overexploitation of natural resources, and the release of harmful chemicals into the environment, can have profound impacts on ecological systems. These impacts, in turn, can affect human health and exacerbate existing health challenges. To capture the planetary health risk, the “Planetary Health Risks Analysis of Urban Agriculture Framework (PHRAUAF)—a heuristic tool connecting social, economic, and environmental risks and benefits of urban agriculture has developed using the findings of the literature review (Fig. 2). From the risks and benefits perspectives, this PHRAUAF advocates for a comprehensive approach to urban agriculture. Various health risks have been presented in the PHRAUAF, which can be categorized into five categories: (1) risk of trace metals in urban farms, (2) health risks associated with wastewater irrigation, (3) zoonotic risks, (4) other health risks, and (5) social and economic risks. A brief description of these categories is provided below.
Fig. 2. Planetary health risks analysis of urban agriculture framework.
The diagram summarizes the risks of UA grouped into three categories: environmental (green), economic (blue), and social (yellow). The colors are solely for aesthetic purposes. The weight of each section is determined by the distribution of articles by type of risk, demonstrating one of our key findings that environmental risks outweigh the social and economic risks.
3.2.1. Urban farm trace metal risk
Bioaccumulation of trace metals, such as lead (Pb), Cadmium (Cd), and Mercury (Hg), among others, in soil and vegetables grown in urban farms can pose potential long-term health impacts (see Fig. 2) such as cancers and immune system, blood, urine excretory, and nervous systems issues in human beings depending on the type and quantity of consumed produce and location of farms.41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52 Economically vulnerable populations are at a disproportionate risk for trace metals presence and contamination in both the Global North and Global South due to high air pollution levels53 and the use of wastewater for irrigation.54, 55, 56 Apart from fruits and vegetables, eggs from backyard poultry farms—an increasingly popular activity in urban areas across the globe—have also been found to have high lead concentrations.57,58
3.2.2. Wastewater irrigation health risks
Wastewater irrigation can pose a risk to health through increased exposure to fecal pathogens through food and accidental water consumption.51 Studies conducted in Ivory Coast, Ghana, and India found urban farmers using lake water and wastewater for irrigation to be at a high risk of infection from pathogens such as Giardia lamblia and Escherichia coli due to poor waste management, fecal drainage in nearby lakes, and lack of self-protective measures during farming.55,56
3.2.3. Zoonotic risks
Backyard livestock farming has also been linked to zoonotic diseases such as influenza and leptospirosis in Bangladesh, Mexico, and Niger from unvaccinated ducks, close interaction between wild and domesticated livestock species, and rodent urine-contaminated water, respectively.59, 60, 61, 62 Urban agriculture has been suggested to provide favourable conditions for breeding insecticide-resistant mosquitoes carrying the malaria virus.63,64
3.2.4. Other health risks
While studies on such important issues of infectious diseases and antibiotic resistance65are limited but still available, other issues like the threat of invasive species from store-bought seeds used in urban agriculture and urban agriculture's carbon footprint were non-existent in the two databases used in this search, proving that research on environmental risks in urban agriculture is still relatively narrow at the moment.
3.2.5. Social and economic risks
Although risks are very limited, the leading social and economic risks of urban agriculture were mainly associated with lack of governance,23,39 inequity of land, water resources, access to knowledge,39,66 gender inequity with women in developing countries being more exposed to contaminants than men54, lack of time,67,68 social conflicts,24 high-priced and insufficient produce,69 and additional costs.70 Other risks not captured by the sample literature could be water damage to roof infrastructure and greenwashing.

4. Discussion
Analysis of the 55 selected articles revealed crucial insights into urban agriculture research. Firstly, it highlighted a substantial increase in attention to urban agriculture over the past decade, particularly since 2015. The field gained further momentum in 2020, which corresponded with the coronavirus disease 2019 pandemic, although the authors make no claim that the pandemic was the primary force behind this upward trend. The analysis also emphasized the significant involvement of European and North American countries in global urban agriculture research.
A key finding of the analysis was the focus on risks outweighing benefits. Environmental risks garnered substantial attention among academics, indicating growing concerns about the potential impact of urban farming on the surrounding ecosystems and the environment. Conversely, research highlighted social benefits more than other types of benefits, suggesting the possible positive effects of urban agriculture on social aspects such as community building and affordability.
However, it is essential to note that the scope of investigating urban agriculture risks remains relatively narrow. A significant portion of the discussions within the risk category centered on trace metal contamination in soil and vegetables, highlighting the need for more comprehensive research on other environmental risks associated with urban farming. The PHRAUAF was introduced to capture the potential risks associated with urban farming. The PHRAUAF identifies the bioaccumulation of trace metals in soil and vegetables as a significant health risk. This accumulation could lead to long-term health issues, including cancers and impacts on various bodily systems. Moreover, urban farmers in economically vulnerable populations are at higher risk of trace metal contamination, necessitating targeted interventions to address this disparity.
The risks associated with wastewater irrigation were also highlighted, indicating the potential for pathogen exposure and infection through contaminated water sources. Backyard livestock farming was linked to zoonotic diseases, emphasizing the importance of maintaining proper animal husbandry practices to minimize health risks.
While the analysis addressed several vital risks, there were limitations in the available literature, particularly in studying infectious diseases and antibiotic resistance in urban agriculture. This indicates a potential gap in understanding and addressing health risks. Similarly, the limited but significant discussion on social and economic risks revealed various challenges, including governance issues, inequity in resource access, gender disparities, time constraints, and social conflicts. These findings underscore the importance of addressing broader socio-economic factors to ensure the sustainable and equitable development of urban agriculture.
Urban agriculture has emerged as a promising remedy for addressing social and economic inequalities on a global scale, with the Global North displaying notable enthusiasm for this practice. Nonetheless, the lack of unpolluted environments in urban areas poses considerable obstacles to the safe and sustainable implementation of urban farming. This study offers valuable insights into the current state of urban agriculture research, exploring its associated risks and benefits. It emphasizes the significance of adopting systems thinking and planetary health perspectives to tackle the challenges and opportunities presented by urban farming. The study underscores the need for ongoing research to foster the sustainable development of urban agriculture while mitigating potential adverse impacts on human health and the environment.
In the context of global health, the significance of urban agriculture is underscored by its increasing popularity as a strategy to achieve Sustainable Development Goals (SDGs), particularly SDG 3: good health and well-being. The urgent call for governments to integrate urban agriculture into city planning emphasizes the need for a careful assessment of associated risks.
The importance lies in preventing the exacerbation of existing illnesses or the emergence of new health challenges. Failing to systematically consider these risks during the planning and implementation of urban agriculture initiatives may have detrimental effects on public health. The study's contribution is pivotal as it provides a comprehensive list of potential risks and benefits to human health and well-being. This information serves as a foundational resource for future, context-specific, and in-depth research endeavors aimed at promoting global health through sustainable urban agriculture practices.
Our study's scope was restricted by the data set we used, as it contained no non-English or grey literature articles. This would have allowed us to examine a broader range of Global South regions where urban agriculture has been practiced for decades. Additionally, since we did not perform a quantitative assessment, our study cannot be utilized as a measuring tool for risk assessment. The main objective of the project was to create a library of articles on the benefits and risks of urban agriculture for members of the scientific community who are interested in or already working on this subject.
5. Conclusion
Urban agriculture is gaining widespread popularity worldwide and is promoted as a potent environmental tool to address social and economic disparities. This surge in enthusiasm is particularly evident in the Global North. However, a significant impediment to its success lies in the scarcity of unpolluted land, water, and air environments in urban areas. This scarcity poses safety concerns for agricultural practices. The adoption of urban farming as an adaptation strategy in resource-scarce regions, especially amidst urbanization, is rapidly gaining traction. Nevertheless, it is imperative to exercise caution in the Anthropocene era, avoiding overly simplistic approaches that may yield adverse effects on society and the environment. Instances such as the impact of windmills on birds and the role of honeybees in biodiversity illustrate potential risks. This study pioneers a comprehensive evaluation of urban agriculture, an age-old yet newly embraced concept, examining its benefits, foreseeable risks, and unforeseen consequences. By shedding light on these aspects, this research also serves as a proactive guide to prevent urban agriculture from becoming a mere greenwashing tool. The findings underscore the significance of meticulous planning, prudent site selection, adherence to best practices, and active engagement with relevant stakeholders to effectively mitigate these risks. The results of this study provide context for considering the risks associated with urban agriculture in the future, as the practice will become more prevalent with increasing urbanization and as a natural remedy for the effects of climate change and food security in urban areas.
CRediT authorship contribution statement
Nilanjana Ganguli, Dahdaleh Institute for Global Health Research & Faculty of Environmental & Urban Change, York University: Conceptualization, Formal analysis, Methodology, Visualization, Writing – original draft, Writing – review & editing. Anna Maria Subic, Dalla Lana School of Public Health, University of Toronto: Methodology, Data curation, Formal analysis. Janani Maheswaran, Faculty of Health, York University: Methodology, Data curation, Formal analysis. Byomkesh Talukder, Department of Global Health, Florida International University: Conceptualization, Formal analysis, Methodology, Visualization, Writing – original draft, Writing – review & editing. References in the original article in Global Health Journal, Volume 8, Issue 1, March 2024.
Nilanjana (Nell) Ganguli is a PhD candidate in the Faculty of Environmental & Urban Change at York University. Her doctoral research focuses on modelling the gendered health impacts of climate change in Malawi using a combination of community participatory methods and soft systems methodologies. She is also a Dahdaleh Global Health Graduate Scholar having demonstrated outstanding academic achievement in global health research and creative activities in line with the themes of the Institute. Her research on "Modelling Health Impacts of Climate Change" takes an intersectional system thinking approach to modelling the gendered health impacts of climate change in Malawi’s capture fisheries.