Research & reports

Threice Natália Ribeiro Pexe, Julia Yumi Muraoka, Fabiana Cristina Donofrio, Cibele Bonacorsi · Scientific Electronic Archives · Brazil (Sinop)

Parasitological and microbiological evaluation was conducted on 40 vegetable samples (watercress, lettuce, chicory, kale, escarole, arugula, parsley) randomly selected from supermarkets, open-air markets, and a community garden in Sinop, Brazil. Before treatment, 12 out of 40 (30.0%) vegetable samples were contaminated with enteroparasites, and all 40 showed microbial growth, with 3 (7.5%) containing Escherichia coli. After sanitization with sodium hypochlorite, parasitic forms were absent, but high initial contamination was confirmed.

Elmira Ramazanova, Manvitha Marni, Roger Wong, Leah Gable, Zezhen Pan, Zorimar Rivera‐Núñez, Daniel E. Giammar · Environmental Geochemistry and Health · United States (St. Louis)

A study in St. Louis, Missouri, examined total metal/metalloid concentrations and in-vitro Pb bioaccessibility in soil from twenty community gardens. Lead was identified as a metal of concern, with soil in 21% of sampled plots containing Pb concentrations above recommended thresholds for gardens. Although Pb bioaccessibility was low (< 5.4%), total metal/metalloid concentrations varied spatially within gardens, and Pb and As concentrations correlated positively with garden age, highlighting the importance of multiple plot sampling.

Malone M., Johnson B., Richard SI., Garcia N., Hamlin S. · Journal of Environmental Management · United States (Seattle)

Compares heavy-metal concentrations in vegetables grown in urban community gardens in the Seattle metropolitan area with produce from the grocery stores participants regularly used — a question set by the partnering farmers themselves. Metal concentrations frequently exceeded health guidelines in both, but were generally higher in the community-garden produce. Cadmium and lead posed the greatest risk and may exacerbate health risks for some populations.

Subin Babu Neupane, Pedro F S Toledo, Katerina Velasco-Graham, Felipe N. Soto‐Adames, Arash Kheirodin · Journal of Integrated Pest Management · United States

This is the first report documenting the invasive thrips species Thrips parvispinus, native to Southeast Asia, in Texas, USA. Samples collected from 12 locations across Texas -- including greenhouse facilities, large retail outlets and community gardens -- from plants showing foliage injury confirmed the species' presence in November 2025, and detections across multiple counties suggest it has been introduced to multiple locations and may be widely distributed in the state.

Candice M. Duncan, Fatemeh Ghezelsofla, Hlengilizwe Nyoni, Jazmin Escobar, Odette Mina · Toxics · United States

A study measuring per- and polyfluoroalkyl substances (PFAS) in irrigation water at two organic farms in Maryland, USA, with no known direct PFAS input, and assessing health risk via a Hazard Index (HI). At agricultural site 1 (AG1), the most abundant compounds were PFBS (37 ng/L), PFBA (24 ng/L) and PFHxA (22 ng/L); the HI showed compliance for branched PFHxS (0.39) but non-compliance for linear PFHxS (1.51). At agricultural site 2 (AG2), despite no known industrial or PFAS-related facilities nearby, HFPO-DA (GenX) was detected at 28 ng/L, and the HI exceeded the compliance threshold (HI = 2.83), with GenX accounting for most of the calculated risk. The findings show HI exceedances occurring at small farm sites with no identifiable contamination source.

Robert J. Moriarity, Meaghan J. Wilton, Eric N. Liberda, Tim Drew, Ada John, Howard Jeddore, Atanu Sarkar, Jim D. Karagatzides, Leonard J. S. Tsuji · Journal of Agriculture Food Systems and Community Development · Canada (Newfoundland)

This study aimed to develop safe community garden sites in Miawpukek First Nation, Newfoundland, Canada, addressing potential soil contamination. Soil testing revealed inorganic arsenic levels exceeding Canadian agricultural guidelines. Hügelkultur-style raised beds with imported soil were used, resulting in undetectable arsenic in potatoes grown there, while potatoes from contaminated soil exceeded safety limits. Kale grown in both raised beds and native soil remained within safety limits.

E. Ryan Harrelson, Qingyue Zeng, Mairui Gao, Magaly Toro, Ryan A. Blaustein · Frontiers in Plant Science · United States (Washington, D.C.)

This study analyzed 87 multidrug-resistant (MDR) bacterial strains from leafy greens (n=29), root zone soil (n=42), and bulk soil (n=16) in Washington, D.C. urban agriculture systems using whole genome sequencing. The isolates, spanning 4 phyla and 14 genera, carried diverse antimicrobial resistance genes (ARGs) and mobile genetic elements (MGEs). The results indicate that MDR bacteria are present in urban agriculture systems, including on fresh produce, dominated by soil-associated taxa carrying diverse ARGs and MGEs, which suggests implications for resistance mobilization.

Carithers, Jaci, Gowen, Samantha, Jenney, Francis · Digital Commons - PCOM (Philadelphia College of Osteopathic Medicine) · United States (Atlanta)

A study in a Metro Atlanta residence, United States, analyzed lead contamination in soil and plant samples using inductively coupled plasma mass spectrometry (ICP-MS). The research found substantial lead contamination, particularly in areas where crops were grown. Results demonstrated the propagation of lead from contaminated soil into local vegetation over time, with an average level of 143.9 mg/kg, ranging from 5.1 mg/kg to 499.5 mg/kg.

Justin B. Richardson, Eric Vukicevich, Eric C. Sirkovich · Bulletin of Environmental Contamination and Toxicology · United States

Soils, sap, and maple syrup were collected from four artisanal maple syrup producers in four suburban areas across the northeastern United States to assess nutrient and trace element concentrations. Soil arsenic and lead concentrations approached or exceeded EPA limits. Sap and syrup arsenic, cadmium, nickel, lead, and zinc concentrations reached or exceeded FDA limits for food.

Ikrema Hassan, Innocent Mugudamani, Saheed Adeyinka Oke · Environments · Canada

Top and subsoil samples from Carleton community garden in New Brunswick, Canada, affected by an industrial fire hazard, were analyzed for toxic heavy metals using ICP-OES and ICP-MS, with ecological risk assessed via the ecological risk factor and potential ecological risk index (PERI) and human health risk assessed using a standard approach. Mean concentrations of lead, zinc, copper and tin exceeded permissible limits under Canadian soil quality guidelines and upper continental crust values; nickel posed a high ecological risk across both soil layers while all other metals showed low ecological risk, and overall PERI indicated low ecological threat. In the human health assessment, children faced non-carcinogenic and carcinogenic risk from arsenic exposure while adults did not face risk from any of the metals studied, identifying arsenic as the primary contaminant of concern and children as the most vulnerable population.

U.S. Environmental Protection Agency · U.S. Environmental Protection Agency (EPA) · United States

This EPA page (last updated December 22, 2025) explains chromated copper arsenate (CCA), a wood preservative used since the 1940s for utility poles, posts, and other structural lumber. Manufacturers voluntarily ended CCA use for residential wood products in December 2003. EPA notes cancer and non-cancer health risks for workers and environmental risks to aquatic invertebrates and plants, while stating there is no health risk to the general public; removal of existing CCA structures is not mandated, though periodic sealant coating is recommended to reduce leaching.

Beatriz Barbosa da Silva, Caroline Senatore, Manueli Monciozo Domingos, Jackline Freitas Brilhante de São José · Ensaios e Ciência C Biológicas Agrárias e da Saúde · Brazil (Vitória)

From March to May 2023, the microbiological quality of food and medicinal plants, soil, and irrigation water was evaluated in an urban garden at an educational institution in Vitória, Brazil. 16.6% (n=2) of the analyzed plants exceeded legal limits for total coliforms at 35ºC, and Salmonella spp. was detected in 41.6% (n=5) of plants. Salmonella spp. was also found in 80.0% (n=4) of soil samples, suggesting a potential source of plant contamination.

Wendy J. Heiger-Bernays, Alicia Fraser, Valerie Burns, Kerry Diskin, Diedre Pierotti, Kian Merchant-Borna, Michael D. McClean, Daniel J. Brabander, H. Patricia Hynes · Scholarworks (University of Massachusetts Amherst) · United States (Boston)

This study identified the nature and extent of soil contamination by polycyclic aromatic hydrocarbons (PAHs) from railroad ties and arsenic from chromated copper arsenate (CCA) pressure-treated lumber in a representative community garden in Boston. Elevated levels of PAHs and arsenic were present in the gardens studied, with these timbers serving as a continuous source of contaminants. This is the first study to investigate contaminants other than lead and evaluate the effect of adding city compost on select soil contaminants in urban garden soil.

Ivonne Alonso Durán, Elizabeth Hernández-Álvarez, Ofelia Mortón-Bermea, Javier Castro-Larragoitia, Margarita Collazo-Ortega · Revista Internacional de Contaminación Ambiental · Mexico (Mexico City)

This study investigated the concentrations of 15 metal(loid)s in four vegetables (tomato, onion, chili, lettuce) cultivated in four urban garden locations in Mexico City. While soil analysis showed only vanadium exceeded Mexican limits in one location, various vegetables harvested in the study exceeded international recommended limits for cadmium, mercury, and lead. Lettuce exhibited the highest metal concentrations and transfer factors, with exceptionally high transfer factors for cadmium in lettuce and mercury in tomato.

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.

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.

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.

Nathália Miasato Pimont, Rafael Alves Santomauro, Carolina De Abreu Pianta, Pablo Menegon Castilho, João Gabriel Neves Viana, Giovanna Carolina Silva Boscolo, Letícia Santos Balbino, Juliana Izidoro Lucas, Aline Ticiani Pereira Paschoal, Italmar Teodorico Navarro, Regina Mitsuka‐Breganó, Fernanda Pinto Ferreira · Ensaios e Ciência C Biológicas Agrárias e da Saúde · Brazil (Londrina)

This study, conducted in Londrina, Paraná, Brazil, between 2019 and 2020, analyzed community garden vegetables for parasites and irrigation water for *Escherichia coli*. *Escherichia coli* and total coliforms were detected in 66.7% (6/9) of water samples. Parasites of *Ascaris*, *Ancylostoma*, and *Entamoeba* genera were identified in vegetable samples, demonstrating contamination of both community garden vegetables and irrigation water.

Luciane Maria Vieira, Leonardo Antunes Pessoa, Vinícius Estevan Carvalho Pereira, Karen Silvério Góis, Edivando Vítor do Couto · International Journal of River Basin Management · Brazil

Water and sediment samples from four sites in a countryside urban-farming watershed landscape in Southern Brazil were analyzed for pollution assessment. All water samples were contaminated with faecal and total coliforms, indicating issues with treatment effectiveness. While pesticide concentrations in water were not significant, sediment copper concentrations were eight times higher than the Threshold Effect Level (TEL), with chromium and copper exceeding TEL at all sites. Sources for zinc, copper, nickel, cadmium, and chromium included plantations, forests, and domestic sewage discharges.

Ainsley C. McStay, S.L. Walser, Eric C. Sirkovich, Nicolas Perdrial, Justin B. Richardson · Journal of Environmental Quality · United States

This study evaluated portable X-ray fluorescence (pXRF) measurements of macronutrients, micronutrients, and toxic elements (As, Pb) in soils and plants from 10 urban community gardens across the eastern United States. It found that pXRF and traditional methods provided agreeable estimates for some elements (Mn, Cu, Zn, Pb) but not for macronutrients (Ca, K, P). While pXRF is an accurate tool for screening Mn, Cu, Zn, and Pb, macronutrients were poorly estimated in fruits, leaves, and roots, and genus-specific and garden-specific factors may be important for plant uptake models.

James D. Blount, Leah E. K. Lenoch, Faith A. Fitzpatrick · Journal of Great Lakes Research · United States

A study of Apple Creek, Wisconsin (119 km²), a Great Lakes tributary like many others subject to Total Maximum Daily Load (TMDL) targets requiring reductions of 51.2% in suspended sediment and 64.2% in total phosphorus. From August 2017 to October 2018, an integrated stream sediment budget and fingerprinting study quantified upland and stream-corridor sources of suspended sediment and sediment-bound phosphorus. Phosphorus concentrations varied among source groups and fluvial sediment types, with higher concentrations in suspended sediment and cropland soils. Eroding streambanks accounted for 100% of the TMDL model's (SWAT) suspended sediment load but only 20% of the total phosphorus load; fine-grained streambed sediment equated to roughly three years of modelled suspended sediment load but only one-third of the total phosphorus load. The two primary sources of fine-grained streambed sediment were streambanks and cropland, with the relative streambank contribution increasing downstream and with watershed area. The relative proportion of suspended sediment varied by season and streamflow, but weighted for representative streamflow, cropland and streambank erosion accounted for 54% and 23% of suspended sediment respectively. Urban land was a source in the upper watershed, but its signature was sequestered by a mid-watershed detention basin, and contributions from construction sites were higher in fall 2018, likely corresponding to increased activity following a wet spring.

K. K. Dey, Maria Velez-Climent, P. Soria, Özgur Batuman, Vessela Mavrodieva, Guo Wei, Jun Zhou, Scott Adkins, John D. McVay · New Disease Reports · United States (Florida)

In October 2019, Tomato brown rugose fruit virus (ToBRFV) was detected in six of eight symptomatic tomato plants from a 1.6 ha community garden in Alachua County, Florida. The plants also showed symptoms of Tomato yellow leaf curl virus (TYLCV), with three samples testing positive for TYLCV. This marks the first report of ToBRFV infecting tomatoes in Florida, USA.

Chammi P. Attanayake, Ganga M. Hettiarachchi, Mónica Palomo, Gary M. Pierzynski, Blanca Calderón · ACS Agricultural Science & Technology · United States

The effect of limestone and composted manure on lead (Pb) in vegetables and Pb bioaccessibility was assessed in a contaminated urban garden (total Pb ~200 mg kg⁻¹). Amendments did not affect Pb in vegetables or Pb bioaccessibility. Peeling reduced Pb concentration in radish by half, and removing surface dust reduced Pb in leafy vegetables by 40-50%. Daily Pb intake from consuming lettuce and carrot/beetroot from this garden was approximately 1.5 times higher than the interim reference level proposed by the U.S. Food and Drug Administration.

Jonathan Hall, Isabel Shargo, Niya Khanjar, Jianna Howard, Laura Schmidt, Ashley Deng, Camryn Edwards, Isabelle Berman, Joseph Galarraga, Sacoby Wilson · Environmental Justice · United States

This study in Baltimore, Maryland, used GIS mapping and spatial analysis to assess the proximity of urban farms to environmental hazards, including those with heavy metal contamination. Analyses indicated that contamination of urban farms is a possibility due to proximity: more environmental hazards were found in census tracts with urban farms, and low-income communities of color had hazards near urban farms. Historically industrial areas showed a higher concentration of environmental hazards with heavy metal or unknown contamination.

Isabel Shargo, Jonathan Hall, Ashley Deng, Niya Khanjar, Camryn Edwards, Isabelle Berman, Joseph Galarraga, Sacoby Wilson · Landscape Journal · United States (Baltimore)

This study in Baltimore, Maryland, used GIS mapping and hotspot analysis to assess the proximity of urban farms to environmental hazards. Most urban farms were located in low-income communities of color. However, most environmental hazards were not near urban farms but in predominantly White areas or historical industrial centers. Despite a generally low risk of contamination, some urban farms in low-income and Black/African American communities were potentially contaminated by hazardous sites.