Research & reports

P. Antwi Agyei, Jeroen H. J. Ensink · Journal of Science and Technology (Ghana) · Ghana (Accra)

A study in Accra, Ghana, from September 2012 to August 2013, analyzed 323 soil and irrigation water samples and 501 produce samples for E. coli, and interviewed 693 participants. It found irrigation water was significantly more contaminated than farm soil, and over 80% of produce samples were contaminated with E. coli, with street food salad being the most contaminated. Key risk factors included farm soil, wastewater use, and poor hygiene, while consumers did not prioritize health indicators despite high risk awareness.

Ladina Knapp, E.J. Veen, H. Renting, J.S.C. Wiskerke, J.C.J. Groot · Urban Agriculture & Regional Food Systems · Europe

This study assessed criteria for the successful establishment and continuity of 29 small-scale, bottom-up urban agriculture (UA) initiatives in the Netherlands and Switzerland, using a vulnerability analysis framework. Biophysical and socio-institutional criteria were analyzed through interviews with project leaders. Findings revealed that the vulnerability of UA systems strongly depends on local circumstances, with the main perturbations and causes of vulnerability originating from social-institutional and human conditions, such as the institutional sphere, local authority assistance, and project leaders' determination.

Godswill Azinwie Asongwe, Bernard Palmer Kfuban Yerima · Greener Journal of Soil Science and Plant Nutrition · Cameroon (Bamenda)

This study analyzed heavy metal levels (chromium, manganese, lead, cadmium) in 21 urban and peri-urban agricultural wetland soil samples in Bamenda municipality, Cameroon. Average concentrations were 35.73 mg/kg for chromium, 0.08 mg/kg for manganese, 30.64 mg/kg for lead, and 0.45 mg/kg for cadmium. These concentrations were generally lower than the maximum WHO permissible levels.

Alexandra Grace Lancey · · United States (Florida)

This ethnographic study in Pinellas County, Florida, investigated school gardening efforts at Title I elementary schools, focusing on an organization that installs gardens in "failing" schools. The research found that strict public school standards and neoliberal education reform paradoxically prevent teachers and administrators from fully utilizing school gardens for nutrition education. This limits their effectiveness in discussing nutrition, healthy eating, and local food, as the focus shifts to state-regulated education standards, revealing significant infrastructural challenges.

Diogo José Amorim de Almeida, Dilamar Dallemole, Arturo Alejandro Zavala Zavala · Revista Ibero-Americana de Ciências Ambientais · Brazil (Varzea Grande)

This study analyzed the urban and peri-urban horticultural production structure in Varzea Grande, Mato Grosso, Brazil, using an exploratory empirical and bibliographic approach followed by Cluster Analysis of primary data from local producers. Despite contributing to food production and maintaining disease-vector-free land, the research found that this activity is in decline. Its low profitability and challenging commercialization process make it unattractive or merely a supplementary income, as small productive forces struggle to sustain themselves against the current market structure and unfavorable social policies.

Christiane Joi Allen · Libraries and Cultural Resources (University of Calgary) · India (Mumbai)

This study evaluated the environmental, social, and economic benefits of urban agriculture in Mumbai, India, using Life Cycle Assessment and Cost Benefit Analysis. Results indicate that urban agriculture has lower greenhouse gas emissions, energy consumption, and water consumption but higher eutrophication potential compared to commercial large-scale agriculture.

Jennifer C. Latimer, David Van Halen, James H. Speer‬, Stephanie Krull, Patricia G. Weaver, Joseph M. Pettit, Heather Foxx · PubMed · United States (Indiana)

This study collected over 1,061 surface soil samples from an approximately 1.25-acre urban community garden in Terre Haute, Indiana, during the summer of 2012, to evaluate the spatial distribution of lead at the plot level. The results highlighted significant variability in lead concentrations within small areas of a former residential property, with some areas showing high lead concentrations (600 ppm). Based on these findings, several areas of concern were identified, and the community garden was reconfigured to reduce potential lead exposure to gardeners and the local community.

Kamal Kishore Yadav, Pradeep Kumar Singh, R. C. Purohit · Water science and technology library · India (Udaipur)

A study in the peri-urban area of Udaipur City, India, investigated heavy metal contamination in soil, vegetable crops, and groundwater due to wastewater reuse. While groundwater-irrigated vegetables showed heavy metal levels within WHO limits, wastewater-irrigated spinach, tomato, and radish at site 3 (Kanpur – Madri Villave) exceeded maximum permissible limits for Fe, Zn, and Cd. Urban wastewater-irrigated spinach was found to accumulate Fe, Zn, and Cd significantly above permissible limits at all three selected locations, making it unsafe for human consumption.

Amy Laura Cahn, Paula Z. Segal · ˜The œFordham urban law journal/Fordham urban law journal · United States

This paper argues that the invisibility of community-stewarded spaces, such as community gardens, within urban governance frameworks in North American cities leads to their enclosure and loss. It highlights that marginalized residents often have the least acknowledged claim to urban space. The study suggests that making existing community-stewarded places visible and exposing pathways to access is crucial to prevent enclosure and promote equity.

Isaiah Sewanu Akoteyon, Adeyemi Davidson Aromolaran · International Journal of Environment and Sustainable Development · Nigeria (Lagos)

This study evaluated peri-urban market gardening and shallow well water quality for irrigation in Lagos, Nigeria. It found that the mean values of bicarbonate, calcium, and pH in shallow wells exceeded detection levels in 66.7%, 60%, and 53.3% of samples, respectively. Salinity and sodium hazard patterns showed that approximately 66.7% of shallow wells had low salinity, 26.7% medium, and 6.7% high.

Taylor L. Frazier, Jin‐Kyu Jung · International Journal of Undergraduate Research and Creative Activities · United States (Seattle)

This study employed a mixed-methods research design to explore the hypothesis that areas around Seattle's P-Patch community gardens were associated with a reduction in crime from 1996 to 2006. Spatio-temporal GIS analyses, statistical analyses, and qualitative interviews with gardeners were utilized. Outcomes of the correlation between P-Patch and crime variables were inconclusive.

Joshua Oluwole Olowoyo, Gladness Nteboheng Lion · South African Journal of Science · South Africa

This review reports on the concentrations of trace metals in crops, including leafy vegetables, harvested from various urban areas. It highlights the presence of trace metals in leafy vegetables and discusses various pathways of uptake, possible health risks associated with urban farming, and morphological and physiological impacts of trace metals in leafy vegetables.

Silvia Mancarella, Giuseppina Pennisi, Daniela Gasperi, L. Marchetti, V. Loges, Francesco Orsini, Giorgio Gianquinto, Gilmo Vianello, Livia Vittori Antisari · Archivio istituzionale della ricerca (Alma Mater Studiorum Università di Bologna) · Brazil (Recife)

This study assessed heavy metal accumulation in an urban garden in Recife, Brazil, at varying distances from a high-traffic road. It found that increasing distance from the street decreased the accumulation of many potentially toxic elements. However, the study revealed a greater human health danger associated with the accumulation of antimony in lettuce, while concentrations of other elements in leaf tissues were within reported thresholds.

Hardiyanto Hardiyanto, Constancio C. de Guzman · Indonesian Journal of Agricultural Science · Philippines (Metro Manila)

This study investigated the levels and distribution of lead (Pb) and cadmium (Cd) in white cabbage, soil, and irrigation water from urban agricultural sites in Las Piñas and Parañaque, Metro Manila, Philippines. Field areas were divided into three sections based on distance from the main road (0, 25, and 50 m), and metal contents were measured by Atomic Absorption Spectrophotometry. The average Pb content (1.09 µg g-1 dry weight) in white cabbage was highest immediately beside the main road, with a similar trend in soil. A negative relationship was found between distance from the main road and Pb and Cd contents in white cabbage and soil. While overall concentrations of Pb and Cd in white cabbage, soil, and irrigation water were within acceptable limits, further study on heavy metal contamination in crops, especially those grown along main roads, was suggested.

Kafeel Ahmad, Zafar Iqbal Khan, Asma Ashfaq, Ameer Khan, Hazoor Ahmad Shad, Mujahid Sher, Zahoor-ul-Hassan Dogar, Ijaz Rasool Noorka, Sumaira Yasmin, Vincenzo Tufarelli, Eugenio Cazzato · The Philippine Agricultural Scientist · Pakistan

This study analyzed heavy metal and metalloid levels in soil and cabbage (Brassica oleracea) from two urban farming sites in Sargodha, Pakistan, irrigated with wastewater. Findings showed that mean concentrations of arsenic (As) and cadmium (Cd) in soil, and manganese (Mn), nickel (Ni), copper (Cu), zinc (Zn), molybdenum (Mo), cadmium (Cd), and lead (Pb) in cabbage, exceeded permissible limits at both sites. Significant differences were observed in metal and metalloid levels in vegetable samples between sites.

Subhashni Raj, Samina Raja, Bree-Ana Dukes · Journal of Hunger & Environmental Nutrition · United States

This study examined the influence of urban agriculture (UA) programming on fruit and vegetable consumption among urban youth in Buffalo, New York. Results indicated that while youth were willing to try new foods, other food behaviors did not change. The study found that UA programming is beneficial but not sufficient to engender healthy eating behavior in youth, with fruit and vegetable consumption also associated with gender and neighborhood median household income.

Noëllie W. Kpoda, Mariam Sou Dakouré, Boubacar Savadogo, Amadou H. Maïga, Jean-Noël Poda, G.B. Kabre · Journal of Water and Environment Technology · Burkina Faso (Ouagadougou)

This study in Ouagadougou, Burkina Faso, compared the parasitological characteristics of wastewater at a treatment plant's inlet and outlet, and in an open channel conveying treated wastewater to a garden site. Non-viable parasite cysts or eggs were found at the treatment plant, but viable parasite cysts and eggs were detected in the open channel. An epidemiological study demonstrated that open defecation by highly infected individuals within the garden site caused recontamination of the treated wastewater.

Eduardo De Miguel, Miguel Izquierdo‐Díaz, Amaia Gómez, Juan Mingot, Fernando Barrio‐Parra · Environmental Toxicology and Chemistry · Spain (Madrid)

Forty-two soil samples from seven urban gardens in Madrid, Spain, were collected to measure concentrations of arsenic, antimony, and selenium, along with soil properties. Antimony concentrations exceeded recommended values for agricultural use in 70% of the urban gardens. A human health risk assessment indicated acceptable levels for noncarcinogenic and carcinogenic risks, though carcinogenic values were elevated, with arsenic identified as the main risk driver.

Prince Antwi-Agyei, Anne Peasey, Adam Biran, Jane Bruce, Jeroen H. J. Ensink · PLoS ONE · Ghana (Accra)

This study, conducted from September 2012 to August 2013 with 490 respondents in Accra, Ghana, assessed knowledge and awareness of wastewater use in urban agriculture. It found low awareness of irrigation water sources among consumers and street food vendors, and low health risk awareness among farmers, despite high awareness among salespersons and consumers. Crucially, consumers did not prioritize health indicators when purchasing produce, and farmers' health risk awareness did not influence their adoption of safer practices.

Emad Abdulrahman Al-Heety, Kadhim H. Yassin, Safa Abd-Alsalaam · Human and Ecological Risk Assessment An International Journal · Iraq (Baghdad)

This study evaluated the health risk of heavy metals (Cd, Cr, Cu, Ni, Pb, Zn) in soils from 14 urban community gardens in Baghdad City, Iraq. The non-carcinogenic hazard index (HI) was below the threshold (HI < 1), indicating no non-carcinogenic hazard. However, the carcinogenic risk index (RI) for Cd, Cr, and Ni exceeded the unacceptable threshold (RI < 1 × 10−4), demonstrating a serious carcinogenic risk for children and adults in the study area.

Heather Ohly, Sarah Gentry, Rachel Wigglesworth, Alison Bethel, Rebecca Lovell, Ruth Garside · BMC Public Health · Global

A systematic review of 40 articles on school gardening programs found that quantitative research was generally of poor quality, with limited evidence for changes in fruit and vegetable intake based on self-report. Qualitative research, though of better quality, attributed a range of health and well-being impacts to school gardens, but more robust quantitative research is needed to support these findings.

Mujtaba Baqar, Nadia Jamil, Naveed Ahsan, Kiran Khanum, Abdul Qadir, Mariyam Zameer, Anam Khalid · Transylvanian Review · Pakistan (Lahore)

This case study investigated the impacts of heavy metals from wastewater irrigation on soil, groundwater, and leafy vegetables (Indian mustard, spinach, fodder) in the Charrar Drain catchment, Lahore, Pakistan. Samples were collected from seven sites. Drain water showed Cd, Cr, and Pb concentrations exceeding limits at most sites, and groundwater Cd concentrations also exceeded limits, though Cr and Pb were within permissible ranges. Soil samples contained Cd, Cr, and Pb, and leafy vegetables irrigated with wastewater showed varying heavy metal concentrations, indicating a heavy metal bioaccumulation issue that may exceed threshold limits.

Masdjidin Siregar · Jurnal Agro Ekonomi · Indonesia (Jakarta)

This paper describes intensive peri-urban leafy vegetable agriculture in Jakarta, which utilizes idle land and provides employment and income for rural migrants. However, the prospect of this agriculture is unclear because it uses non-agricultural land that will eventually be developed. The study concludes that government assistance in credit, extension, and research is needed, and alternative lands for cultivators must be found.

Kirsten Schwarz, Bethany B. Cutts, Jonathan London, Mary L. Cadenasso · Sustainability · Global

This paper proposes reframing the issue of soil lead contamination and urban gardening in shrinking cities from a potential conflict to a potential solution. Many shrinking cities face high soil lead burdens from their industrial past and the historic use of lead-based paint and leaded gasoline, which is often seen as a barrier to urban agriculture. The paper argues that urban gardening can be a solution to the soil lead problem through soil management, including soil testing and the addition of amendments, and through social network and community building.

Daniel Orlins Trigg · ScholarWorks -A service of University of Vermont Libraries (University of Vermont) · United States

This study investigated food insecurity screening among clinicians in Vermont, where 76% of residents experience some level of food insecurity. It found that physicians and physician assistants prefer using an established two-item screen for food insecurity. However, these clinicians tend to underestimate the actual prevalence of food insecurity in their practice communities.