Research & reports

Elliot Buckminster, Charlotte Breckenridge, Thomas Sedgwick · International Journal of Research in Agronomy · United Kingdom

This research quantified soil-to-plant transfer factors for six heavy metals (Cd, Pb, Zn, Cu, Ni, Cr) in lettuce, spinach, and carrot across 20 peri-urban agricultural sites in Berkshire, UK, from 2021-2022. Cadmium exhibited the highest mean transfer factor (0.31), and at 4 of 20 sites, cadmium concentrations in lettuce exceeded the EU maximum limit of 0.20 mg/kg fresh weight. Soil pH was a strong predictor for Cd and Zn transfer factors, with TFs increasing below pH 6.0.

Cosimo Dondini, Xavier Úbeda, Giacomo Certini, Marcos Francos · Journal of Soils and Sediments · Spain (Barcelona)

This study analyzed soils from ten urban gardens in Barcelona, Spain, with a special focus on possible contaminants. Irrigation water was also analyzed, and some of the waters contained a high concentration of salts and nitrites, which are listed as a pollutant. While three tests for heavy metals did not attest to significant pollution, other toxic elements not considered in this study could come from road transport gases or the port of Barcelona. Overall, the soil quality was concluded to be suitable for growing vegetables.

Lee D. Bryant, Roy Maconachie, Bastian Schnabel, Abubakarr Swaray, Howard Gigi, Solomon Gbanie, Kabba Haroun Bangura, Anthony Kamara, Prince Antwi-Agyei · Water Science & Technology Water Supply · Sierra Leone (Freetown)

This paper examined the environmental health status of three urban and peri-urban agriculture (UPA) sites in Freetown, Sierra Leone. Qualitative and quantitative data revealed heavy metal concentrations significantly exceeding regulatory limits in sweet potato leaves and arable soil. Additionally, soaring levels of faecal coliform bacteria were found in irrigation water, and crops were identified as hyperaccumulators for environmental contaminants.

Jinrong Tong, Dongsheng Feng, Xia Wang, Min Wang, Mei-Lian Chen, Yanfen Chen, Yingqing Ma, Bo Mei, R. Chen, Mengfeng Gao, Siwen Shen, Hongkang Wang, Weiyi Zhang · Heliyon · China (Shanghai)

A study investigated pesticide residues and dietary intake risk in 7028 vegetable samples grown under modern urban agriculture in Shanghai from 2018 to 2021, analyzing 68 types of pesticides. Pesticide residues were detected in 29.21% of samples, with 0.47% exceeding China's national maximum residue limits (MRLs). The target hazard quotient (THQ) and hazard index (HI) for detected pesticides were all less than 1, suggesting there may be no obvious health hazard for residents.

Anushi Anushi, A. Krishnamoorthi, Jitendra Chaurasia, Bijay Kumar Baidya, Abhishek Singh, ­ Sapna, Vijay Kumar, Anushka Singh · Journal of Scientific Research and Reports · Global

This review explores the historical evolution and diverse models of urban farming, highlighting their contributions to food security, environmental sustainability, and community resilience. Challenges faced by urban farmers include limited space, soil contamination, regulatory hurdles, and access to resources.

Nyayu Khodijah, Ratna Santi, Riwan Kusmiadi, Ivan Rismunandar · Jurnal Agritech · Global

This research investigated the effect of nutrient type and lead (Pb) absorption on water spinach growth in a Kratky hydroponic system over 30 days. Plants were exposed to PbSO4 concentrations of 50, 100, 150, and 200 mg/L, with standard hydroponic (ABmix) and alternative nutrients. The study found that nutrient type significantly affected most growth parameters, with ABmix performing better than alternative nutrients. Crucially, no growth disturbance was observed due to PbSO4 contamination, and the combination of Pb concentration and nutrient type did not significantly affect growth or production, except for the number of leaves.

ke Chinelo Gloria, Eze H.C, Obasi C.J, Euphemia Afoma Ikegwuonu, Okonkwo Ngozi Nonyelum · International Journal of Research Publication and Reviews · Nigeria

To evaluate the water quality of the Obibia River in Amawbia, Anambra State, Nigeria, water samples were collected monthly and assessed for bacteriological and physicochemical parameters. The study identified multiple bacterial isolates, including Escherichia coli, Klebsiella pneumoniae, Salmonella enterica serovar Typhi, and Vibrio cholerae. Notably, E. coli, S. Typhi, and V. cholerae were frequently observed in both rainy and dry seasons. These findings suggest the necessity of adequate treatment before use and periodic evaluation of the water's quality for drinking and urban agricultural purposes.

Simone Trimmel, Stefan Wagner, Laura Feiner, M. Feiner, Daniela Haluza, Rebecca Hood‐Nowotny, Ulrike Pitha, Thomas Prohaska, Markus Puschenreiter, Philipp Spörl, Andrea Watzinger, Elisabeth Ziss, Johanna Irrgeher · Environmental Science and Pollution Research · Europe

A study of urban gardens in Vienna, Austria, building on a previous study of eleven gardens in the city that found elevated lead (Pb) levels in some soil and plant samples. This work examined the elemental composition of soil and plants from two of the affected gardens one year after compost amendment. ICP-MS analysis of tomato fruit skin, pulp and seeds showed only minor variations in elemental composition unlikely to affect food safety, whereas radishes showed a tendency toward contaminant accumulation in root tips and leaves. Washing lettuce significantly reduced levels of potentially toxic elements including Be, Al, V, Ni, Ga and Tl, underscoring the importance of washing garden produce before consumption; compost amendment was associated with reduced Zn, Cd and Pb levels in radish bulbs. Lead isotope ratios in soil and spinach leaf samples from the earlier study, assessed by MC-ICP-MS, showed a direct linkage between the Pb isotopic signatures in soil and spinach leaves, supporting their use as tracers of Pb sources in the environment.

Anne-Kristin Løes, Sebastian Eiter, Tatiana Rittl · Environmental Sciences Europe · Europe

Using soil data from ten peri-urban case farms near Oslo and Bergen, Norway, this study estimated how quickly potentially toxic element (PTE) concentrations would rise in soil under intensive application of compost or digestate from food waste, composted garden waste, or horse and poultry manure applied annually to meet a theoretical carrot crop's nitrogen, phosphorus and potassium demand. Under this intensive fertilization scenario, Norwegian soil quality limits for PTEs would be reached within 20-85 years, faster in soils with more organic matter, with limits reached first for copper and zinc, both essential micronutrients. The urban waste-based fertilizers were also found to be poorly balanced in macronutrients, with rates covering potassium demand leading to high phosphorus and nitrogen surpluses. The study concludes Norway's PTE regulations are stricter than the EU's and do not support recycling organic matter and nutrients from urban waste.

Gizaw Ebissa, Aramde Fetene, Hayal Desta · City and Environment Interactions · Ethiopia

Treated wastewater from the plant serving Bole Lemi Industrial Park (BLIP) in Addis Ababa, Ethiopia was sampled at the treatment plant's influent and effluent and analyzed using a treated wastewater quality index (TWWQI) to assess suitability for urban irrigation agriculture. The aggregate TWWQI classified the water as 'very poor' for urban irrigation agriculture, with heavy metals contributing 85% of that grade, nutrient load 4%, salinity 8%, and miscellaneous contaminants 4%. Discrete indices varied: heavy metals scored 'very polluted', nutrients 'excellent', salinity 'poor', and miscellaneous contaminants 'good'. Contaminant removal efficiency ranged from 30% to 100% (58% in aggregate), and some contaminants showed higher concentrations in the effluent than the influent, indicating the treatment plant failed to remove them. Cr3+, Cl− and TDS contributed most to the poor rating, and the plant was found to need upgrading to increase removal efficiency.

Annamaria Gentile, Luca Di Stasio, Gianmaria Oliva, Giovanni Vigliottá, Angela Cicatelli, Francesco Guarino, Werther Guidi Nissim, Massimo Labra, Stefano Castiglione · Environmental Research · Global

A review examines the dynamics of antibiotic resistance (AR) in urban soils, cataloguing multiple sources that introduce antibiotics into urban soil, including domestic wastewater, industrial effluent and urban agricultural practices, as well as microplastics and domestic animal excrement. It states that the selective pressure from these anthropogenic sources promotes the proliferation of antibiotic-resistant bacteria through horizontal gene transfer among soil microorganisms, poses a significant public health threat by potentially transferring resistance genes to human pathogens via direct contact, food consumption and water ingestion, and disrupts microbial community dynamics in ways that affect soil fertility, plant growth and overall environmental quality.

Gamal El Afandi, Hossam Ismael, Souleymane Fall · Sustainability · United States

Using a hybrid approach combining the HYSPLIT and AgDRIFT models, this study estimated organophosphate pesticide spray drift from corn and soybean fields into urban-agricultural interface communities in Sangamon County, Illinois, at both field and county scales. Preliminary findings indicate that all residential areas near agricultural land are at risk of pesticide drift, since buffer zones do not exceed 25 meters; of 34 water bodies (rivers, lakes, streams, and drains) within the 30,200-acre study region, 12 fall within the high-drift zone, and roughly 106 buildings across an estimated 10,300 km² were found to have potential exposure to drift.

Elżbieta Skorbiłowicz, Piotr Ofman, Mirosław Skorbiłowicz, Marcin Sidoruk, Urszula Tarasiuk · Water · Poland

This study assessed heavy metal contamination in 96 surface sediment samples collected from urban, agricultural, and forested areas of the Bug River catchment in Poland between July 2018 and 2020, measuring metals (Zn, Pb, Cr, Ni, Cu, Fe, Mn, Cd) by atomic absorption spectroscopy and applying the geoaccumulation index (Igeo), contamination factor (CF), and pollution load index (PLI). Urban sediments showed significantly higher heavy metal concentrations than agricultural or forested areas, with cadmium reaching up to 2.5 mg/kg; the average Igeo for cadmium was 0.24 in agricultural areas and 0.15 in urban areas, while the highest PLI values, reaching a maximum of 0.33, occurred in urban areas, and statistical analysis showed both urban emissions and agricultural activities significantly influenced heavy metal presence in the sediments.

Arcadius Martinien Agassin Ahogle, Sammy Letema, Gertrud Schaab, Veronica Ngure, Abraham R. Mwesigye, Nicholas Kibet Korir · Frontiers in Soil Science · Kenya (Nairobi)

This study assessed heavy metal and trace element contamination risks in peri-urban farmlands in Nairobi city catchment, Kenya, by analyzing 60 soil samples from ten vegetable farming zones. Results showed elevated concentrations of elements including As, Cd, Mn, Pb, and Zn, with some exceeding permissible agricultural thresholds. As, Cd, Hg, and Pb exhibited high ecological risks, with Cd contributing 46-66% of the overall risk.

Myeong Seok Jeong, Mina Lee, Chaw Su Lwin, Kwon-Rae Kim · 한국토양비료학회지 · Korea (Jinju)

This study investigated heavy metal concentrations in soil and crop leaves from 23 urban gardens in Jinju, Korea, to assess suitability for cultivation. While average concentrations of As, Cd, Cr, Cu, Ni, Pb, and Zn generally did not exceed Korean guidelines, the Geoaccumulation Index indicated ongoing contamination by Cd, Cu, Pb, and Zn. A significant amount of Pb was introduced into some soils from the atmosphere, and continuous monitoring for heavy metals in urban garden soils is required for food safety.

Muhammad Luqman, Muhammad Uzair Awan, Shaukat Khan, Razzaq Ahmed, Hsi‐Hsien Yang, Muhammad Rizwan Goraya · Agricultural Water Management · Pakistan (Lahore)

A study in Lahore, Pakistan, investigated trace element (TE) contamination in water, soil, fodder, and buffalo milk due to the use of untreated wastewater from the Hudiara drain for agriculture. Samples collected along the drain showed that TE contamination, including Cd, Cu, Ni, and Zn, increased from upstream to downstream sites. Concentrations of these elements in water, soil, fodder, and milk surpassed permissible limits, indicating a significant transferability risk up the food chain and high Hazard Index values for irrigation water, fodder, and milk.

Moussa Coulibaly · International Journal for Advanced Studies and Research in Africa · Côte d'Ivoire (Korhogo)

This study in Logokaha, Korhogo, Côte d'Ivoire, aimed to show the impact of urban agriculture on food production and the health of farmers. Despite contributing to the empowerment of farmers, urban agriculture exposes them to health hazards. The methodology involved documentary research and field surveys.

COULIBALY Moussa · International Journal of Advanced Research · Côte d'Ivoire (Korhogo)

This study in Korhogo, Côte d'Ivoire, surveyed 81 farmers to assess the impact of urban agriculture on food production and farmer health. It found that urban agriculture, predominantly practiced by women (85.19%) with no formal education (71.61%), involves the use of chemical fertilizers and pesticides with non-adherence to application intervals. A significant portion of farmers (59.26%) discard chemical packaging in the environment. Despite contributing to empowerment, this practice exposes farmers to health problems including fatigue (53.09%), injuries (25.92%), skin burns (11.11%), dry coughs/colds (32.10%), and diarrheal diseases (19.75%).

Alicja Kicińska, Justyna Wikar · Plant and Soil · Global

This study assessed human health risks from contact with contaminated soil and consumption of plants grown in contaminated soils in allotment gardens and farmlands located in areas affected by Zn-Pb and steel industries and hard coal mining. Using US EPA methodology and pseudo-total concentrations of Potentially Toxic Elements (PTEs) in soil and plant samples, estimated daily intake and non-carcinogenic and carcinogenic health risks were analyzed for recreational and residential exposure scenarios. Findings indicated that the proportion of different exposure pathways in total health risk decreased in the order: intake of contaminated vegetables > accidental soil ingestion > dermal contact > inhalation of contaminated soil particles, and children are more exposed to toxic effects of PTEs than seniors and economically active adults.

Weisong Chen, Weixuan Xian, Guiying He, Zhongye Xue, Shaomin Li, Wenyan Li, Yongtao Li, Yulong Zhang, Xingjian Yang · Ecotoxicology and Environmental Safety · China (Guangzhou)

A study in seven districts of Guangzhou City, China, evaluated the large-scale occurrence and spatiotemporal distribution of 16 PAHs and 14 OPAHs in urban agricultural soils. Average concentrations of ΣPAHs and ΣOPAHs during the flood season (59.6 ± 31.1-213 ± 115.5 μg/kg) were significantly higher than during the dry season (42.1 ± 13.3-157.2 ± 98.2 μg/kg). Coal combustion and traffic emissions were identified as the dominant sources for these contaminants in both seasons.

Bethaney Turner · · Global

This chapter explored human-soil relations in urban home and community gardens through ethnographic fieldwork. While biodiverse soil offers direct health benefits, the presence of contaminated, toxic soils, prevalent in lower socio-economic neighborhoods, was shown to expose inequities in access to safe gardening sites and hinder the realization of potential therapeutic benefits. It argues that the therapeutic benefits of gardens are best realized when humans cultivate attentive relationships with myriad multispecies companions.

Jordi Guimera Garcia, Natalie Bray, Yowhan Son, Aleah L. Butler-Jones, Sara Perl Egendorf, Jenny Kao‐Kniffin · Journal of Urban Ecology · United States (New York City)

In New York City, a study investigated plant growth (tomato, pepper, kale) in soils constructed from four municipal composts mixed with sediments from the NYC Clean Soil Bank, to assess the potential for safe urban agricultural soils. While Clean Soil Bank sediments enhanced plant growth when mixed with BRL compost, they also negatively impacted tomato aboveground biomass production by 29% in LES compost and tomato plant height by 18% in QBG compost, indicating variable effects depending on compost properties.

Gerhard Fischer, F. Fischer · Revista Colombiana de Ciencias Hortícolas · Global

This overview, based on the ScienceDirect database, addresses heavy metal (HM) contamination in vegetables from urban and peri-urban areas. It notes that HMs like Cd, Pb, Hg, Cr, and As accumulate to toxic levels in the soil-plant-consumer continuum, causing health damage to consumers and physiological alterations in plants. Leafy and solanaceous vegetables accumulate the most HMs, while cucurbits and legumes are least affected.

Julia Reichl, Christina Proßegger, Bernhard Eichholzer, Pamina Plauder, Maria Sophia Unterköfler, Karin Lebl, Alexander Indra, Hans‐Peter Fuehrer · Parasitology Research · Austria

In allotment gardens and a second location in Graz, Styria, Austria, citizen scientists collected adult Aedes albopictus mosquitoes and eggs, which underwent morphological examination and DNA barcoding. A total of 217 eggs and 14 adult specimens were found, indicating that Aedes albopictus is already breeding in Graz. However, continued monitoring efforts are needed to determine if stable populations can survive there.

Eri Saikawa, Erin Lebow-Skelley, Rosario Hernandez, Faith Flack-Walker, Leann Bing, Candis M. Hunter · Journal of Public Health Management and Practice · United States (Atlanta)

In Atlanta, Georgia, in-person and virtual Soil Screening, Health, Outreach and Partnerships (soilSHOPs) were implemented through a community-engaged partnership to screen soils for lead. These soilSHOPs informed best practices for increasing awareness about lead exposure and led the US Environmental Protection Agency to identify a Superfund site, confirming soil lead contamination.