Heavy metal contamination in agricultural soils poses serious threats to food safety, ecosystem integrity, and public health. This study investigates the concentrations, ecological risks, and human health impacts of nine heavy metals Cr, Mn, Co, Ni, Cu, Zn, Pb, As, and V in homestead agricultural soils collected from two depths, surface (0–20 cm) and subsurface (21–50 cm), across industrial and non-industrial regions of Bangladesh, using inductively coupled plasma mass spectrometry (ICP-MS). Results revealed that surface soils from industrial areas exhibited the highest metal concentrations in order of Mn > Zn > Cr > Pb > V > Ni > Cu > As > Co. However, maximum As levels were detected in non-industrial areas, suggesting combined influences of local geology, intensive pesticide application, and prolonged irrigation with As-contaminated groundwater. Elevated concentrations in surface soils indicate recent contamination with limited downward migration. Multivariate statistical analyses indicated that industrial and urban activities are the major sources of contamination, whereas Mn remains primarily geogenic, controlled by natural soil forming processes. Contamination factor (CF) and pollution load index (PLI) analyses identified Pb and As as the principal pollutants, with hotspots in Nairadi, Majhipara (Savar), Gazipur sadar, and Chorkhai (Mymensingh). Ecological risk (ER) assessment highlighted As and Pb as the dominant environmental stressors, though overall risk remained low. Human health risk analysis showed that ingestion is the primary exposure pathway, with children being more susceptible than adults. Although the hazard index (HI) values were within the acceptable safety limits, the estimated carcinogenic risks for As and Cr exceeded the USEPA thresholds, indicating potential long term health concerns. Therefore, the cumulative carcinogenic risk (CCR) results demonstrate that As is the primary driver of lifetime carcinogenic risk in homestead soils, followed by Cr, while contributions from other metals are minimal. These findings emphasize the urgent need for continuous monitoring, improved industrial waste management, and targeted mitigation strategies to ensure safe food production, a cleaner environment, and better public health.

Agricultural soils near roadways are increasingly contaminated with presumably contaminating elements (PCEs), raising concerns for food safety and health risks in Bangladesh. This study quantified Mn, As, Co, Cr, Zn, Ni, Cu, Cd and Pb in roadside agricultural farm soils at three depths (0–5, 5–10, 10–15 cm) across industrial, peri-urban, and research areas using ICP-MS. The average mass fractions ranked as Mn > Zn > Cr > Ni > Cu > Pb > Co > As > Cd with peri-urban soils exhibiting the elevated levels of Cr (80.48 mg.kg⁻¹ and Ni (65.81 mg.kg⁻¹). Contamination indices indicated Cd (Contamination Factor: 2.01–2.53) and Ni (Contamination Factor: up to 2.27) as the most enriched elements, with all sites showing a Pollution Load Index (PLI) >1 (1.07–1.66), reflecting cumulative soil deterioration. Cd posed moderate ecological risk (Er: 60.3–75.9), whereas other PCEs were low risk. Health risk assessment showed elevated non-carcinogenic hazard indices (HI: 7.87–10.5 for children; 3.72–4.78 for adults), with Mn, Cr, and Co as major contributors. Cumulative carcinogenic risk (CCR) values were dominated by Cr, reaching 7.22 × 10⁻⁴ in industrial areas and 3.98 × 10⁻⁴ in peri-urban areas, exceeding the acceptable range (10⁻⁶–10⁻⁴). Metal mass fractions were consistently higher in surface soils (0–5 cm) than at deeper layers, indicating anthropogenic deposition from traffic and industry. Multivariate analysis distinguished geogenic (Cr-Ni-Cu; Mn-Co-As) from anthropogenic (Cd-Pb-Zn) sources. These findings identify Cd and Cr as priority pollutants, highlighting the need for soil management and pollution control near roadways in Bangladesh.

Heavy metal contamination poses significant ecological and public health concerns due to its persistence, toxicity, and bioaccumulative potential of toxic metals, threatening environmental quality and sustainable development. This study evaluated the distribution, pollution status, health risks, and sources of heavy metals in soils from industrial, agricultural, and residential areas of Rivers State, Nigeria, using Inductively Coupled Plasma–Mass Spectrometry (ICP-MS). Elevated concentrations of As, Mn, Se, Zn, and Co were detected across the study locations. Arsenic recorded the highest concentration in the Trans-Amadi industrial area (366.8 mg/kg), while Mn and Zn reached maximum concentrations of 1312 mg/kg and 327.9 mg/kg in Woji and Egi, respectively, exceeding the DPR limits for soil HMs. Pollution indices, including contamination factor, geo-accumulation index, enrichment factor, pollution load index, and Nemerow Integrated Pollution Index, revealed moderate to severe contamination, with the industrial zone exhibiting a NIPI value of 12.5. Health risk assessment identified ingestion as the dominant exposure pathway. Hazard quotient values for As (9.15) in the children category exceeded USEPA-acceptable limits, indicating potential non-carcinogenic risks. Carcinogenic risk assessment identified arsenic as the principal carcinogenic contaminant, with ingestion-derived Incremental Lifetime Cancer Risk (ILCR) values in the industrial area exceeding the USEPA maximum acceptable lifetime cancer risk threshold (1 × 10⁻⁴), particularly among children, whereas the carcinogenic risks associated with the other investigated metals generally remained within acceptable or tolerable limits. Source identification indicated that industrial emissions, vehicular activities, waste disposal, and agricultural practices were the primary contributors to heavy metal accumulation. These findings provide critical scientific evidence for targeted remediation, pollution prevention, and informed health-risk environmental management to protect soil quality, ecosystem integrity, and public health. The study supports evidence-based policies that advance sustainable land management, environmental protection, and progress in Rivers State, Nigeria.

Microplastic (MP) contamination in terrestrial ecosystems has emerged as a critical environmental concern, particularly in agricultural soils influenced by anthropogenic activities. This study investigated the depth-wise distribution, polymer composition, and associated ecological and human health risks of MPs in homestead agricultural soils across four regions of Bangladesh representing different levels of industrialization: Narayanganj (old industrial), Savar (moderate industrial), Gazipur (emerging industrial), and Mymensingh (non-industrial). Soil samples were collected from two depth intervals (0–20 cm and 21–50 cm), and MPs were extracted using density separation, identified through microscopic analysis, and characterized via ATR-FTIR spectroscopy. A diverse range of MP morphologies and polymers was detected, with irregular particles and fragments dominating the composition. Polypropylene (PP), high-density polyethylene (HDPE), and polyethylene terephthalate (PET) were the most abundant polymers, reflecting widespread domestic, industrial, and agricultural plastic usage. MP abundance was consistently higher in surface soils, indicating dominant surface inputs, although vertical migration into subsoil layers was evident. Spatial analysis revealed higher MP contamination in industrial regions, particularly Narayanganj and Savar, compared to the non-industrial reference site. Ecological risk assessment indicated low risk levels across all regions; however, significant spatial variability was observed. Human exposure assessment demonstrated that inhalation was the primary pathway, followed by dermal contact and ingestion, with children exhibiting higher exposure levels than adults. Lifetime average daily dose (LADD) and carcinogenic risk estimates remained below acceptable thresholds, suggesting minimal immediate health risks. Nevertheless, the persistence, mobility, and cumulative nature of MPs highlight potential long-term concerns. Therefore, this study provides comprehensive insights into the sources, distribution, and risks of MPs in homestead agricultural soils and underscores the need for improved waste management practices, sustainable agricultural strategies, and long-term monitoring to mitigate environmental and human health impacts.

Microplastic (MP) contamination of agricultural soils is an emerging environmental concern because MPs may alter soil physicochemical properties and nutrient dynamics. However, information on polymer- and soil-dependent responses in South Asian agricultural systems remains limited. This study investigated the temporal effects of polypropylene (PP) and polyethylene terephthalate (PET) microplastics (≤20 μm) on soil pH and dissolved ion concentrations in agricultural soils from Gazipur and Mymensingh, Bangladesh. Soil–MP composite systems were prepared with a 1% (w/w) MP loading and incubated under controlled laboratory conditions for 30 days, with measurements conducted on days 1, 15, and 30. Concentrations of NH₄⁺, Na⁺, SO₄²⁻, Cl⁻, and Br⁻ were determined by ion chromatography. The results showed substantial temporal and treatment-dependent variation in soil pH and ion concentrations. PP-containing systems showed pronounced changes in NH₄⁺, whereas PET-amended Mymensingh soil exhibited marked changes in SO₄²⁻ and Br⁻. Na⁺ generally declined during incubation, while Cl⁻ showed pronounced short-term variation. PCA identified distinct patterns among the measured ions, with three components explaining 91.471% of the total variance. These findings indicate that PP and PET microplastics can be associated with changes in nutrient and ion dynamics under controlled laboratory conditions, with responses varying according to polymer type, soil characteristics, and incubation time. However, the single MP concentration, short incubation period, limited polymer types, non-sterile experimental conditions, and incomplete nitrogen speciation limit direct extrapolation to field conditions. Further studies using environmentally realistic concentrations, longer incubation periods, diverse and aged polymers, complete nitrogen speciation, and soil–plant or field systems are needed to clarify the broader implications of MP contamination in agricultural soils.

Rice is the staple food crop of Bangladesh, playing a critical role in national food security. This study investigated the morpho-physiological traits and the impact of source-sink manipulations on grain yield in four rice varieties Binadhan-14, Binadhan-19, China IRRI and Kalihatta under field conditions. Various treatments, including partial spikelet and flag leaf removal at different growth stages, were applied to assess their effects on yield components. Among the tested varieties, Binadhan-19 exhibited the highest grain yield under normal conditions, attributed to a greater number of grains per panicle and fewer sterile spikelets. Source-sink manipulations revealed that spikelet removal significantly increased individual grain size and weight, indicating that yield was sink-limited. Conversely, flag leaf removal reduced grain size and weight, emphasizing the importance of source strength for grain filling. These findings highlight that grain yield in rice is co-regulated by both source activity, sink capacity and strategic manipulation of these factors could be a promising approach in breeding programs aimed at enhancing rice productivity.