Research & reports

K M Tanjida Islam, Md Shahin Mahmud · Pharmacon Jurnal Farmasi Indonesia · Bangladesh

This study characterized multidrug-resistant (MDR) Shigella flexneri strains from contaminated raw vegetables in Bangladesh, retrieved from the NCBI genome database. Whole-genome sequences of four S. flexneri strains from tomatoes and green chilies in Gazipur and Dhaka were analyzed. The analysis identified 4273 core genes and 44 antibiotic resistance genes, with five essential hub genes (tolC, acrA, emrK, emrB, evgS) identified as high-priority therapeutic targets for compromising MDR mechanisms in food-borne S. flexneri.

Anaïs M. Kipelo, M. Jothilakshmi, Dhafer Mohammed M. Al Salah, Georgette N. Ngweme, Emmanuel K. Atibu, Crispin K. Mulaji, Periyasamy Sivalingam, John Poté · Toxicology Reports · Democratic Republic of the Congo (Kinshasa)

This study examined trace element levels in Brassica pekinensis Lour. from urban gardening sites (Cecomaf and Lutendele) in Kinshasa, Democratic Republic of the Congo, and associated human health risks. Analysis showed that Cr, Cu, Cd, Pb, and Hg concentrations in samples from both sites exceeded FAO/WHO maximum permissible limits. Health risk assessments indicated that Estimated Daily Intake (EDI) values for Cd and Pb exceeded recommended limits, and Target Hazard Quotient (THQ) values exceeded 1 for most metals, suggesting potential non-carcinogenic risks.

Amon Abraham, Andrew G. Mtewa, Chimwemwe Chiutula, Richard Lizwe Steven Mvula, Alfred Maluwa, Fasil Ejigu Eregno, John Njalam’mano · International Journal of Environmental Research and Public Health · Malawi (Blantyre)

This cross-sectional study in Blantyre, Malawi, characterized antibiotic-resistant bacteria (ARB) prevalence in 35 samples from five livestock farms, including manure, soil, and vegetables. It found high contamination, with Escherichia coli dominating pig manure (52%) and farm soil (35%), and Klebsiella pneumoniae contaminating all sample types (up to 67% in home soils, 60% in vegetables). All manure isolates showed sulfamethoxazole–trimethoprim resistance, and vegetables exhibited severe multidrug resistance, including 100% E. coli resistance to gentamicin. Composting for ≤6 weeks did not eliminate ARBs, indicating manure-amended farms are AMR reservoirs.

Laxman Barua, YOGITA ADHIKARI, Kuldeep Naik · International Journal of Agriculture and Nutrition · India (Prayagraj)

This research assessed heavy metal concentrations in agricultural soils near the Naini industrial area in Prayagraj, India, and evaluated remediation strategies. Lead and cadmium concentrations at 0.5 km from the industrial zone exceeded Indian permissible limits (Pb: 67.8 mg/kg vs 50 mg/kg; Cd: 6.4 mg/kg vs 5 mg/kg). A pot trial showed that Brassica juncea removed 34.7% of Pb and 41.2% of Cd, while lime + biochar reduced Pb by 52.4%. A combined approach reduced bioavailable Pb to below the permissible limit.

E.N. Jenkins, John M. Galbraith, Anna Paltseva · SOIL · Global

This study conducted a literature review of 84 publications to evaluate the accuracy, precision, and practicality of Portable X-ray fluorescence (PXRF) as a tool for analyzing heavy metal contamination in urban soils. Urban soils often face contamination with heavy metals like lead and arsenic, and PXRF was shown to achieve reliable accuracy when properly calibrated. PXRF emerges as a viable method for assessing urban soil contamination.

M. J. Ni, Shuai Yan, Ting Li, Zijun Zhou, Xiaojing Liu, Shirong Zhang, Guiyin Wang, Xiaoxun Xu, Yulin Pu, Yongxia Jia, Lan Li · Ecotoxicology and Environmental Safety · China (Chengdu)

This study investigated heavy metal (HM) contamination in urban and peri-urban agricultural soils of the Chengdu Plain, China, using an integrated multi-model approach. Four major HM sources were identified, including natural (30.0%), mixed agricultural and transportation (29.5%), metal smelting (19.4%), and atmospheric deposition (21.1%). Risk assessments revealed that Cd and Hg posed the highest ecological risks, and human health risk assessment indicated unacceptable health risks for children, with non-carcinogenic and carcinogenic risk probabilities reaching 4% and 10% respectively.

Yukarie Ayu Wulandari, Ade Sumiahadi, Dirgahani Putri, Helfi Gustia, Rosdiana · Jurnal AGROSAINS dan TEKNOLOGI · Indonesia (Jakarta)

This study, conducted from March to June 2025 in East Jakarta, investigated heavy metal contamination levels in mustard greens grown through urban agriculture. Mustard green samples were collected from five sub-districts, and lead (Pb) and cadmium (Cd) content was measured. Results showed that Cd absorption in mustard greens was very low, well below national and international maximum standards, but Pb absorption exceeded both national (0.5 ppm) and international (0.3 ppm) maximum permissible standards. No strong correlation was found between air quality and Cd or Pb content in the mustard greens.

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.

Álvaro Luis José Reyes Córdova · Horizontes Amazónicos · Ecuador

A bibliographic review of research on water quality in the Puyo River and its tributaries in Pastaza, Ecuador, compiled studies from scientific databases and institutional repositories reporting physicochemical, microbiological, and heavy metal parameters. The main sources of contamination were found to be wastewater discharges, fecal coliforms, and accumulation of heavy metals such as lead and mercury linked to urban, agricultural, and mining activities, with community perception aligning with technical findings as most of the population rated the water poor quality and associated it with health problems. Over the past twenty years, a progressive deterioration in water quality parameters has been documented, with increases in turbidity and pathogenic microorganisms despite some isolated recovery efforts, and the review concludes that lack of attention from the municipality and prefecture, together with the absence of continuous monitoring, is worsening the water crisis and demands comprehensive, participatory governance.

Jacek Antonkiewicz, Iwona Paśmionka, Grzegorz Szychowski · Soil Science Annual · Poland

Following a flood that inundated allotment gardens in Nysa, southern Poland, for up to 14 days after the water rose on 14 September 2024, researchers analyzed 12 soil samples collected in early spring 2025 from two allotment garden sites. Most soils were found limed and disinfected, with high organic matter but low total potassium, sodium and sulfur. Zinc and copper concentrations exceeded the average for Polish arable soils, pointing to use of materials enriched with these elements.

Pierre‐Alexandre Deyris, Franck Pélissier, Claire M. Grison, Claude Grison · Journal of Hazardous Materials Advances · Global

Herbicide use worldwide has doubled over the past 30 years, and diuron contamination of tropical aquatic ecosystems — affecting food crops such as pineapple — has been reported across Southeast Asia, the Pacific, and Africa. This perspective article examines taro (Colocasia esculenta), a widely cultivated crop whose tubers are consumed locally, as a nature-based means of mitigating diuron impact on tropical aquatic ecosystems through rhizofiltration, i.e., phytoaccumulation of the herbicide by the roots. Analysis of treated tubers found that diuron levels in the tuber core were below recommended European standards, indicating the tubers could remain edible for the local population and confirming compatibility with existing food uses.

Abubakar Mohd Habu, Ali Sanusi Hassan, Adeniyi Olarewaju Adeleye, Michael Edet Nkereuwem, Ijanu Emmanuel Madu, Garba Barde Bate, Olukemi Adeleye, Usman Mohammed Isah · Biological Environment and Pollution · Nigeria

This study assessed heavy-metal accumulation and non-carcinogenic health risks in commonly consumed leafy vegetables -- lettuce, spinach, and cabbage -- cultivated with wastewater in Zawaciki, Kano State, Nigeria. Vegetable and rhizospheric soil samples were analyzed for cadmium, lead, chromium, nickel, zinc, and copper using atomic absorption spectrophotometry, and bioaccumulation factors (BAFs) were calculated as the ratio of metal levels in plant tissue to soil. Metal concentrations varied significantly across the vegetables (p < 0.05), with lead in lettuce leaves exceeding the FAO/WHO permissible limit by more than 120 times; chromium in cabbage reached 32.22 mg/kg, while lettuce showed elevated zinc (19.83 mg/kg) and copper (9.26 mg/kg). Hazard-quotient risk assessments found HQs for chromium and lead both exceeding 1, and the cumulative hazard index exceeded 1 for all vegetables, reaching its highest value of 18.861 in lettuce.

Md. Rafiqul Islam, Syed Anisur Rahman, Tanvir Ahmed · International Journal of Agriculture and Food Science · Asia

Six heavy metals (lead, cadmium, chromium, nickel, copper, zinc) were measured by atomic absorption spectrophotometry in spinach, amaranth and fenugreek collected from four peri-urban sites around Dhaka, Bangladesh, during January-March 2024, where more than 2,000 hectares of vegetable land are irrigated with untreated industrial and domestic wastewater via canal networks. Lead in amaranth from the industrial-effluent site reached 0.94 mg/kg fresh weight, more than three times the WHO/FAO permissible limit of 0.30 mg/kg, while cadmium, chromium and nickel stayed within permissible limits at all sites and zinc, though highest in absolute terms (8.6-14.7 mg/kg), also remained within safe limits; contamination was highest at the industrial-effluent site and lowest at the borewell-irrigated control site, indicating a localized food-safety risk for consumers of peri-urban leafy greens grown with wastewater irrigation.

Jarosław Chmielewski, Barbara Gworek, Alicja Walosik, Magdalena Florek-Łuszczki · Annals of Agricultural and Environmental Medicine · Poland

Soil (N=196) and root vegetable (N=94) samples from 16 allotment gardens in Warsaw, Poland, were analyzed for manganese, zinc, copper, lead and cadmium and assessed for health risk. Parsley, carrots, beetroots and celery grown in these gardens accumulated elevated levels of all five metals, and the health risk assessment found an increased risk of carcinogenic effects from cadmium and lead in consumers of these root vegetables; the authors conclude consumption of vegetables from the examined gardens should be very limited or eliminated from the diet entirely.

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.

Jennifer Newell, Siobhan Cox, Rory Doherty · Urban Agriculture & Regional Food Systems · Global

A systematic review synthesized literature on the oral bioaccessible fraction (BAF) of arsenic, cadmium, chromium, nickel, and lead in vegetables grown on contaminated soils, drawing values from multiple online databases across potentially toxic elements (PTEs), in vitro test methods, and vegetable types. The review starts from the premise that many urban and peri-urban brownfield sites carry a legacy of soil metal and metalloid contamination, so crops grown there may pose human health risks. Median PTE BAFs ranked Cd > Ni > Cr > As > Pb; among in vitro methods, the unified BARGE method (UBM) produced the highest median BAFs (63.0% gastric, 59.6% gastrointestinal); and by crop type, BAFs ranked non-vegetables (e.g., rice, fungi) > legumes > root vegetables > bulb vegetables > leafy vegetables.

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.

Chmielewski J., Wszelaczyńska E., Pobereżny J., Florek-Łuszczki M., Gworek B. · Sustainability · Poland

The study sampled 112 items — 72 vegetable and 40 fruit — from 16 allotment gardens in Warsaw and measured Fe, Mn, Zn, Cu, Pb and Cd. Vegetables accumulated markedly more heavy metals than fruits, and leafy vegetables grown near high-traffic roads carried the highest Pb, Cd and Zn. Lead exceeded permissible limits by six to twelve times and cadmium by one to thirteen, leading the authors to advise against growing tomatoes in urban settings. Only trace amounts appeared in fruits, and the Hazard Index rated the fruits alone as safe. The paper calls for continuous monitoring of urban garden soils, remediation of contaminated ground and safer growing practices.

Yizhou Peng, Grigorieva Iya Yu · Ecological Indicators · China (Chengdu)

This study assessed heavy metal pollution in rural, urban-rural interface, and urban agricultural lands in Chengdu, China. It found varying degrees of heavy metal pollution across all areas, with arsenic (As) and cadmium (Cd) being the most severe pollutants. Concentrations of As and Cd in soil samples exceeded risk thresholds, and these elements showed high spatial variability, indicating significant anthropogenic influence. Pollution sources included livestock manure, natural sources, agricultural activities, and industrial activities in urban areas.

Roopika Sivaraman, Haritha Thulaseedharan Nair, Sharmila Krishnan, Perumal Siddhuraju · Soil and Sediment Contamination An International Journal · India (Coimbatore)

This study analyzed biocompost and water samples from four agricultural nurseries in semi-urban Coimbatore, India, for microplastic contamination using density separation and ATR-FTIR. While physicochemical properties met Indian standards, microplastic fragments (85%) and fibers (15%) were found in two biocompost samples (BC-B and BC-C), identifying PMMA, PP, and EVA polymers. No microplastics were detected in samples BC-A and BC-D, but the findings suggest semi-urban agricultural gardening may contribute to microplastic accumulation in terrestrial environments, potentially harming soil and plant health.

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.

Miles P.A. Bate-Weldon, Jill L. Edmondson, Katie J. Field · iScience · Global

This study investigated the effect of urban environmentally relevant concentrations of zinc in soils on nutrient exchange between arbuscular mycorrhizal fungi and pea plants using radio-isotope tracing. It found that at higher zinc concentrations, the transfer of phosphorus from fungi to plants and carbon from plants to fungi dramatically decreased. The results suggest that while urban horticulture has potential for food production, the unchecked presence of contaminants like zinc in urban soils may critically hinder its realization.

Anjoulie Brandner, Karolina Taczanowska, Brenda Maria Zoderer, Christoph Schunko · Urban forestry & urban greening · Austria (Vienna)

A survey of 458 respondents in Vienna, Austria, analyzed urban wild food foraging locations and preferences for urban green spaces (UGS). 1239 foraging locations were identified across 9 UGS types, with forest and meadow landscapes, parks, and UGS mosaics being most utilized. Foragers' major concerns were contamination from traffic and dogs.

Dragana Šunjka, Sanja Lazić, Slavica Vuković, Siniša Berjan, Hamid El Bilali · · Serbia

This chapter examines the food safety of urban agriculture systems in the Republic of Serbia through selected case studies. It highlights that agricultural products from urban production may be contaminated by polluted soil, water, and air, as well as by pesticides, heavy metals, persistent organic pollutants, nitrate and nitrite, and mycotoxins. The study emphasizes the need for strict control and reduction of synthetic pesticides and other agrochemicals in urban agriculture.

Mohammad Reza Khalilnezhad, Mohammad Taheri, Alessio Russo, Negin Nasseh, Ahmad Taheri · Cities & Health · Iran

This study investigated factors affecting lead and cadmium levels in urban fruits in Tehran's Tarasht neighborhood, Iran, due to heavy traffic and urban gardens. It found that sites taller than 10 meters had the highest cadmium, while sites without barriers or with 4-meter barriers showed the highest lead content. Barrier width, urban fruit tree height (for lead), distance to the street, and fruit type also influenced heavy metal absorption, indicating significant contamination risks.