Rapid urbanization and industrial growth in China have increased brownfield site reclamation, the sustainable remediation for urban transformation and enhancing ecosystem services. However, traditional brownfield safety assessment strategies impose unnecessary costs since excessive remediation. Herein, a comprehensive system integrated by soil self-purification, potential ecological risks and human health risks is developed to investigate the safety of brownfield sites. Indices, including soil environmental loading capacity (SELC), and Nemerow integrated pollution index (NIPI), were introduced to assess heavy metals (HMs) pollution. Results show that 72.05% of the sites are identified as moderate pollution, where Cd, As, and Cr(VI) are at heavy pollution, incorporating soil self-purification. The average values of potential ecological risk (PERI) reached 6615.00, posing a significant damage to the local ecosystem, and Cd was identified as main ecological hazards in the study sites. Furthermore, the health risk assessment shows that children's health risks are higher than that of adults, with non-carcinogenic risk to children (2.60) and adults (0.41), and carcinogenic risk to children (2.30 x 10-3) and adults (1.12 x 10-4). Utilizing a multi-index decision-making approach, it is determined that 19.30% of the site exhibit high-risk values, between concentration screening (11.40%) and risk screening (83.30%) base on single-indices. The study sheds light on the comprehensive assessment of brownfield site safety.
This study examines the key drivers behind the continued reliance on traditional biomass fuels such as charcoal and firewood in urban areas of developing countries, including the city of Lubumbashi. The paper focuses on economic constraints, health problems associated with the use of these fuels, the environmental consequences of growing use and also looks at the alternatives for cooking and their accessibility. The various reasons behind the growing and constant use of charcoal and firewood are examined in the context of the city of Lubumbashi and other developing countries. However, the continuous supply of charcoal and firewood not only contributes to the degradation of forests and the extinction of species, but also disrupts the livelihoods of forest-dependent families and exacerbates soil erosion. The charcoal production process is intrinsically damaging to both the environment and human well-being. Not only does it emit large quantities of CO2, contributing to atmospheric pollution, but it also presents health risks for both producers and users. The smoke and soot generated during charcoal production expose people to harmful substances, leading to adverse health effects and even premature death, particularly among children. This review also discusses the impact of this production and use on the education of women and children, who are responsible for cooking and harvesting firewood, resulting in a higher illiteracy rate among women. Faced with the need to take global action to mitigate the impact of climate change, global carbon dioxide emissions must be drastically reduced to meet the Paris Agreement target of zero net emissions by 2050. A practical and sustainable solution is discussed in this review as an alternative to traditional cooking systems namely solar cooking, which offers enormous potential, provided it is accessible, and is an excellent alternative to the heavy reliance on biomass for household energy needs in developing countries.
Industrial development has caused significant environmental damage, especially through potentially toxic element (PTE) pollution. Combining pollution indices, health risk assessment, spatial autocorrelation (Moran's I), and receptor modeling (APCS/MLR), this study quantified sources and risks of heavy metals in smelting-adjacent farmland soils, facilitating targeted PTE pollution mitigation. Soil analysis revealed significantly elevated mean concentrations of As (326 mg/kg), Cd (23 mg/kg), Cr (104 mg/kg), Cu (106 mg/kg), Ni (73 mg/kg), Pb (274 mg/kg), and Zn (660 mg/kg), all exceeding Yunnan provincial background values. The average total non-carcinogenic risk index (HIadult = 2, HIchild = 11) and total carcinogenic risk index (TCRadult = 5.52 x 10-4, TCRChild = 6.44 x 10-4) for both adults and children exceeded the threshold (HI = 1, TCR = 1 x 10-04). The results of environmental pollution evaluation show that the overall pollution in the study area is a heavy pollution level. The ACPS-MLR model showed that Cd and Zn in soil mainly came from industrial activities (37%). Cu and Pb were derived from motor vehicle emissions and agricultural activities (20%). As may be derived from agricultural and industrial activities. Furthermore, based on the combination of source apportionalization and the spatial distribution of environmental pollution, the northeastern part of the study area and transportation hubs are the key pollution areas and need to be given priority for treatment. PTEs accumulate in the soil, will be enriched through the food chain, and seriously threaten human health and soil ecological environment. Therefore, this study can provide a basis for identifying, preventing, and controlling the risk of PTEs pollution in soil.
Soil contamination with arsenic (As) is becoming a serious concern for living organisms. Arsenic is a nonessential metalloid for plants, humans, and other living organisms. Biochar (BC) is a very effective amendment to remediate polluted soils and it received great attention owing to its appreciable results. Arsenic toxicity negatively affects plant morph-physiological and biochemical functioning and upsurges the generation of reactive oxygen species (ROS), which negatively affect cellular structures. Arsenic toxicity also reduces seed germination and impedes plant growth by decreasing nutrient uptake, causing oxidative damage and disrupting the photosynthetic efficiency. Plants use different strategies like antioxidant defense and increased osmolyte synthesis to counteract As toxicity; nevertheless, this is not enough to counter the toxic impacts of As. Thus, applying BC has shown tremendous potential to counteract the As toxicity. Biochar application to As-polluted soils improves water uptake, maintains membrane stability and nutrient homeostasis, and increases osmolyte synthesis, gene expression, and antioxidant activities, leading to better plant performance. Additionally, BC modulates soil pH, increases nutrient availability, causes As immobilization, decreases its uptake and accumulation in plant tissues, and ensures safer production. The present review describes the sources, toxic impacts of As, and ways to lower As in the environment to decrease its toxic impacts on humans, the ecosystem, and the food chain. It concentrates on different mechanisms mediated by BC to alleviate As toxicity and remediate As-polluted soils and different research gaps that must be fulfilled in the future. Therefore, the current review will help to develop innovative strategies to minimize As uptake and accumulation and remediate As-polluted soils to reduce their impacts on humans and the environment.
Chlorpyrifos (CHP) contamination affects agricultural land and poses significant risks to plants and humans. Chitosan-oligosaccharide (COS) enhances plant resilience under stress and boosts the activity of enzymes metabolizing exogenous substances. This study aimed to explore the potential and mechanism of COS in mitigating CHP phytotoxicity and reducing CHP accumulation through both pot and field experiments. The results indicated that CHP exposure caused oxidative stress and decreased photosynthesis by 18.5 % in wheat. COS up-regulated the expression of antioxidant enzyme genes in CHP-stressed plants, resulting in a 12.1 %-29.4 % increase in antioxidant enzyme activity, which resulted in an 11.3 %-12.8 % reduction in reactive oxygen species (ROS) and an 11.5 %-14.7 % reduction in malondialdehyde (MDA) content in leaves and roots, respectively. Additionally, COS increased chlorophyll content by 6.6 % by regulating genes related to chlorophyll metabolism, enhancing photosynthesis by 13.6 %. COS also reduced CHP uptake and accelerated its metabolism by upregulating CYP450, GST, and lignin biosynthesis-related genes. Wheat treated with COS exhibited a 26.7 %-28.7 % reduction in grains' CHP content, resulting in a lower health risk index (HRI). These findings provide novel insights into the potential of COS in alleviating CHP phytotoxicity and reducing its accumulation.
Cadmium (Cd) is a highly toxic heavy metal contaminant found in soil and water due to human activities such as mining and industrial discharge. Cd can accumulate in the body, leading to various health risks such as organ injuries, osteoporosis, renal dysfunction, Type 2 diabetes (T2DM), reproductive diseases, hypertension, cardiovascular diseases, and cancers. The gut is particularly sensitive to Cd toxicity as it acts as the primary barrier against orally ingested Cd. Even at low concentrations, Cd can cause oxidative stress, inflammation, and intestinal bleeding. Cd also disrupts the gut microbiota, affecting its structure, taxonomic composition, and metabolic functions. Cd exposure alters the structure of the gut microbial community, reducing diversity and upregulating certain phyla and genera. This disturbance can lead to physiological and metabolic imbalances, including disruptions in energy homeostasis, amino acid, lipid, nucleotide, and short-chain fatty acid (SCFAs) metabolism. The effects of Cd on the gut microbiota depend on the duration of exposure, the dose of Cd, and can vary based on sex and age. Cd-induced gut dysbiosis has been linked to various diseases, including diabetes, adiposity, atherosclerosis, liver damage, infections, cancer, and neurodegenerative diseases. Interventions targeting the gut microbiota, such as probiotics, specific diets, melatonin, selenium, vitamin D3, and certain compounds, have shown potential in reducing the health risks associated with Cd exposure. However, combined exposure to Cd and other toxicants, such as microplastics (MPs), heavy metals, and antibiotics, can amplify the toxicity and dysbiosis in the gut microbiota.
Rare earth elements (REEs) are increasingly recognized as significant environmental pollutants due to their environmental persistence, bioaccumulation, and chronic toxicity. This study assessed REEs pollution in soil, water, and vegetables in an ion-adsorption rare earth mining area in Ganzhou, and evaluated the associated health risks to the local population. Results indicated that the REEs content in soil ranged from 168.58 to 1915.68 mg/kg, with an average of 546.71 mg/kg, substantially surpassing the background level for Jiangxi Province (243.4 mg/kg) and the national average (197.3 mg/kg). Vegetables displayed an average REEs content of 23.17 mg/kg in fresh weight, far exceeding the hygiene standard of 0.7 mg/kg. Water samples contained REEs at a concentration of 4.09 mu g/L. The estimated daily intake (EDI) of REEs from vegetables exceeded the threshold for subclinical damage, posing potential health risks, particularly for children and adolescents. Further analysis of the adjusted average daily intake (ADI) and non-carcinogenic risk suggested that while most vegetable consumption remains within safe threshold, the intake of REEs from high-risk vegetables such as pakchoi should be limited. Overall, carcinogenic risks associated with lifetime cancer risk (LCR) model for REEs exposure through vegetables and water were found to be low in this area.
INTRODUCTION Tobacco farming plays a crucial role in the livelihoods of many rural communities in Pakistan, particularly in Khyber Pakhtunkhwa (KPK). However, this agricultural practice is associated with severe environmental degradation and significant health risks to workers during cropping. METHODS This study evaluates the ecological and health impacts of tobacco farming in Pakistan, employing both quantitative (surveys) including 200 respondents (farmers and field workers/laborers) and qualitative methods (in-depth interviews) involving 10 respondents (farmers, policy experts, agriculturist and environmental specialists). The research focuses on Swabi, a key tobacco-growing region, and highlights the negative effects of excessive pesticide use, fertilizer application, and deforestation, which contribute to soil erosion, water pollution, and biodiversity loss RESULTS Regression analysis shows that pesticide use ((3=0.65, p<0.001) and deforestation ((3=0.82, p<0.001) are the leading contributors to ecological degradation. The relationship between tobacco yield and environmental degradation, although showing a trend (p=0.062), is statistically negligible and unlikely to have practical significance ((3=-0.15). Health risks are equally concerning, with farmworkers (labor hired for farming, farmers, landlords) exposed to harmful agrochemicals and nicotine absorption leading to respiratory diseases, skin conditions, and green tobacco sickness (GTS). Pesticide exposure ((3=0.71, p<0.001) and contact with tobacco leaves ((3=0.53, p<0.001) significantly impact workers'health, while using personal protective equipment (PPE) helps mitigate these risks ((3=-0.43, p=0.001). The study also reveals that many farmers are interested in transitioning to alternative crops like maize or cotton, but they face financial and informational barriers. CONCLUSIONS The growing of tobacco in Pakistan entails significant ecological and health dangers, emphasizing the immediate need for the implementation of sustainable farming strategies to mitigate environmental harm and enhance the socio-economic conditions of farmers. Government support through financial incentives, educational programs, and sustainable farming techniques is essential to reduce the environmental damage and improve public health.
Continuous misuse of difenoconazole (DFZ) results in farmland contamination, posing risks to crops and human health. Salicylic acid (SA) has been shown to enhance plant resistance and reduce pesticide phytotoxicity and accumulation. However, whether SA effectively reduces DFZ phytotoxicity and accumulation and its underlying mechanisms remain poorly understood. To address this, a short-term indoor experiment and a long-term outdoor pot experiment were conducted to evaluate the potential of SA to alleviate DFZ-induced phytotoxicity and its effects on DFZ uptake, translocation, metabolism, and accumulation. The underlying mechanisms were explored through physiological, biochemical, and gene expression analyses. The results showed that DFZ induced oxidative damage and reduced photosynthesis by 15.6% in wheat. SA upregulated the expression of genes encoding antioxidant enzymes (POD, CAT, SOD1, and SOD2) in the roots and leaves of DFZ-exposed plants, leading to a 7.5%-13.4% increase in antioxidant enzyme activities and a subsequent 9.7%-14.5% decrease in reactive oxygen species levels. Additionally, SA increased the total chlorophyll content by 16.3%, which was enhanced by regulating chlorophyll synthesis and degradation-related genes, thereby improving the net photosynthetic rate by 12.2%. Furthermore, SA upregulated the expression of lignin biosynthesis-related, CYP450, and GST genes, which reduced DFZ uptake and accelerated its degradation. Consequently, the wheat grain DFZ content decreased by 36.2%, thus reducing the health risk index. This study confirms the potential of SA to reduce DFZ phytotoxicity and accumulation. Based on these findings, we recommend using SA in DFZcontaminated areas to mitigate phytotoxicity and the associated human dietary exposure risks.
There has been a growing concern on the health effect of edible plants growing near/on/within the vicinity of dumpsites. This study investigated two edible vegetables: Amarathus hybridus and Talinum triangulare (Jacq) grown in the vicinity of a major informal dumpsite of electronic waste in Nigeria. The levels of polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and heavy metal concentrations in the vegetables were measured. The health risks of consuming the vegetables were assessed using the hazard index (HI), lifetime cancer risk (LCR), estimated daily intake (EDI), and hazard quotient (HQ). Using the Ames Salmonella fluctuation test on Salmonella typhimurium (TA100 and TA98) and the SOS chromo test on Escherichia coli (PQ37), the mutagenicity and genotoxicity of the vegetables were evaluated. The two vegetables have elevated levels of heavy metals, PBDEs, PCBs, and hazardous PAHs. Compared to A. hybridus, , T. triangulare was more contaminated. The amounts of organic constituents and heavy metals in the vegetables correlated favorably. The levels of the HQ, HI, and LCR were above the suggested guideline values, indicating a significant risk of both carcinogenic and non-carcinogenic consequences, particularly in children. The two vegetables were mutagenic even at 50 % concentration in the Ames test. This was corroborated with SOS-chromo test results showing that the two vegetables were indeed genotoxic. This study demonstrated the harmful effects of growing food crops close to dumpsites; therefore, sufficient measures should be implemented to stop farmers and individuals from utilizing dirt from dumps as fertilizer or from planting in soil that has been used as a dump in the past or present.