Health risk assessment of heavy metals via consumption of dietary vegetables using wastewater for irrigation in Swabi, Khyber Pakhtunkhwa, Pakistan

Nickel uptake in leafy greens from contaminated soil: an investigation into phytoavailability and health risk assessment using in vitro digestion model

Nickel (Ni) is a toxic metal that not only pollutes the environment but also causes harmful impacts on plant growth and human health. Therefore, it is crucial to assess the relationship between the phytoavailability of Ni in soil and its accumulation in edible and non-edible parts of vegetables. A pot experiment was conducted to investigate Ni uptake in three different leafy vegetables, spinach (Spinacia oleracea L.), lettuce (Lactuca sativa L.), and fenugreek (Trigonella foenum-graecum L.), grown in soil artificially contaminated with Ni at three different treatment levels (100 mg kg-1, 200 mg kg-1, and 300 mg kg-1). The potential dietary toxicity of these vegetables in humans was examined by using an in vitro digestion model. The lowest and highest chlorophyll contents were detected in lettuce at 300 mg kg-1 of Ni concentration and in control plants of spinach. Their values were 34.16 ± 3.01 (SPAD unit) and 53 ± 3.7673 (SPAD unit), respectively. Among the three vegetables, lettuce and spinach at 300 mg kg-1 exhibited the highest accumulation of Ni, with 43 mg kg-1 in edible parts and 182 mg kg-1 in non-edible parts. Furthermore, health risk index (HRI) values were found to be > 1 for lettuce and fenugreek at Ni concentrations of 200 and 300 mg kg-1 for both children and adults. The average bioaccessibility of Ni in lettuce, fenugreek, and spinach during the gastrointestinal phase was 32-23%, 24-10%, and 45-37%, respectively, at a Ni concentration of 300 mg kg-1. All three vegetables grown on Ni-contaminated soil may potentially contribute to food chain toxicity. The HRI values being > 1 suggest that these vegetables are unsafe for consumption. Monitoring of Ni concentration in leafy vegetables is essential to minimize human health risks associated with food chain contamination.

Assessing Leaching of Potentially Hazardous Elements from Cookware during Cooking: A Serious Public Health Concern

The intake of toxic metals from cooking utensils through food is of growing concern to the medical community. This intake poses serious risk to human health. In many developing countries, different types of contaminated metals scraps are used to make cooking utensils. The leaching of both nutritionally essential and toxic metals in significant quantities from cookware during the cooking process results in food contamination and poses a substantial health risk. In the present study, the leaching of some toxic and potentially toxic metals from cooking utensils into different solutions and food was investigated. A preliminary survey indicated that the majority of individuals tend to use aluminum cookware due to its affordability, overlooking the potential health risks associated with these inexpensive and lower-quality cooking utensils. XRF analysis revealed that aluminum, steel, and copper cookware had K, Ca, Pb, Cd, Ni, V, Sn Mo, Zn, Bi, and Tb as contaminants. In addition, aluminum (3.2 ± 0.25 to 4.64 ± 0.20 g/kg) and copper cookware (2.90 ± 0.12 g/kg) were highly contaminated with lead. The time and pH-dependent study revealed that leaching of metals (Al, Pb, Ni, Cr, Cd, Cu, and Fe, etc.) into food was predominantly from anodized and non-anodized aluminum cookware. More metal leaching was observed from new aluminum cookware compared to old. Acidic food was found to cause more metals to leach during cooking. Blood metal analysis of the local population revealed the presence of high concentrations of Al, Pb, Cd, and Ni. In conclusion, leaching of toxic or potentially toxic metals from cookware into food, especially from anodized and non-anodized aluminum cookware, poses a potential public health risk. Practical applications: Cooking utensils are routinely used for the preparation of food. However, the harmful impact posed by these essential items is largely unknown. The current research briefly explains the toxic metals leaching from cookware in a pH-dependent manner and leaves a message to the public, especially in developing countries like Pakistan, regarding the type of cookware suitable for cooking purposes.

Amassing of heavy metals in soils, vegetables and crop plants irrigated with wastewater: Health risk assessment of heavy metals in Dera Ghazi Khan, Punjab, Pakistan

Human health is the main concern related to use of crop products irrigated with contaminated irrigation sources. Present research has been conducted to explore heavy metal status of sewage and industrial wastewater being used up for irrigation purpose in the peri-urban areas of the district Dera Ghazi Khan which has not been explored widely before. The analysis also followed heavy metal detection in the subsequent irrigated soil and vegetables/crop plants in relation to assessment of health risk to the consumer to plan the future monitoring in this area. An unremitting boost of heavy metals into the environment from wastewater irrigation has become a global issue. These heavy metals enter the food chain and pose health assumptions to consumers upon utilization. In the present study, an investigation has been conducted to determine metal concentrations in the wastewater, soil, and different plant species. For wastewater samples, pH, total dissolved solids (TDS), electrical conductivity (EC), and selected heavy metals such as Al, As, Cr, Cu, Fe, Mn, Pb, Zn, and Ni were determined. The mean values of heavy metals in the soil samples were within the WHO/FAO safe limit, while Cr and Pb were the most frequent (100%) among the metals. However, differentiating the sites, the concentration of Cr and Cu, Ni, and Fe were elevated. The metal transfer was highly effective from soil to the growing plants i.e. brinjal, red corn, wheat, tomato, and spinach than other plant species. Among the metals, Cr, Ni, Mn, and Pb in plant samples were exceeding the WHO/FAO safe limit. Health risk index (HRI) have revealed the possible potential risk of heavy metal contaminated plant species in the order of spinach (6.4) > wheat (6.4) > brinjal (5.9) > tomato (4.7) > red corn (4.5) > apple gourd (4.3) > white corn (3.8) > cabbage (3.1) > luffa (2.9). Likewise, HRI of different metals was calculated as Cu (19.6) > Zn (17.9) > Cr (2.95) > Ni (0.85) > Mn (0.48) > Fe (0.15) > Cd (0.11) > Pb (0.05) > As (0.00001). The level of HRI through the use of dietary plants revealed an elevated risk level than the acceptable limit (HRI > 1) for Cu > Zn > Cr in adults. Our findings suggest that there would be a serious health risk to the consumers due to the consumption of these plant species being irrigated with the wastewater. Therefore, a strict regulatory mechanism is proposed for the safety of food plants in the study area including monitoring and recycling of crop plants, and building water treatment plants to remove pollutants and clean wastewater.

Heavy metal accumulation efficiency and subsequent of cytogenotoxicity evaluation in the medicinal plant Equisetum hyemale

Heavy metals in soils represent a threat to the environment, food safety, as well as human and animal health. The bioaccumulation of these elements in plants might enhance medium- and long-term adverse health risk promoting genetic alterations that lead to dermal, gastrointestinal, circulatory, renal, and brain disorders. The present study aimed to determine the bioaccumulation potential and cytogenotoxic effect of Equisetum hyemale extracts. E. hyemale seedlings were divided into two groups: exposed group (plants cultivated in soil with heavy metals solution) and control (plants cultivated in soil with distilled water). Heavy metals were quantified in the cultivation soils (control and exposed) and extracts (ethanolic and infusion) of vegetative parts from E. hyemale cultivated in both soils. Root length and cytogenotoxic effect were determined utilizing Allium cepa bioassay. Data demonstrated that Equisetum hyemale present the ability to absorb and bioaccumulate different heavy metals including lead, copper, cobalt manganese, zinc, iron and chromium. Given this property E. hyemale may be considered a reliable bioindicator to assess cytogenotoxicity of certain substances that exert adverse risks to environment and human and animal health.

Assessment of Heavy Metal Accumulation in Soil and Garlic Influenced by Waste-Derived Organic Amendments

Simple Summary

The utilization of organic wastes, for example, poultry waste, sugarcane press mud, and farmyard manure is extremely common among farmers from South Asia including Pakistan. We assess the biochemical nature and dietary benefit for plants and record the presence of heavy metals in garlic following cultivation in a soil amended with these organic wastes. Present investigation showed the grouping of toxicity and bioaccumulation of heavy metals with a particular link to their source of origin and highlight the hazard of some of them for public health through their excessive utilization. Selecting appropriate manure can significantly reduce health risks for humans.

Abstract

In South Asia, the high costs of synthetic fertilizers have imposed research on alternative nutrient inputs. We aimed to identify potential trace elements (PTE) present in some organic manure that might be a source of environmental pollutions and risk to public health following consumption. The study aims to evaluate how different organic waste (poultry waste, PW; press mud, PM; and farmyard manure, FYM) influences the heavy metal migration in soil, the accumulation in garlic, and their potential health risks. Organic waste caused a higher accumulation of certain metals (Zn, Cu, Fe, and Co), whereas Mn, Cd, Cr, and Pb were in lower concentrations in soil. Amendments of soil with PM revealed a higher accumulation of Cd, Cr, Fe, and Pb, whereas PW resulted in Cu and Zn accumulation in garlic. Treatment of soil with FYM exhibited higher metal concentration of Co and Mn. An environmental hazard indices study revealed that pollution load index (PLI) was highest for Cu following treatment with PM. The health risk index (HRI) was greater for Cd following amendment with PM. Maximum daily intake of metals (DIM) was observed for Zn after treatment with PW. The Pb exhibited maximum bioconcentration factor (BCF) in PM-amended plants. Based on these findings, we concluded that garlic grown on contaminated soil with organic waste may pose serious health hazards following consumption.

Heavy-Metal Speciation Distribution and Adsorption Characteristics of Cr (VI) in the Soil within Sewage Irrigation Areas

While sewage irrigation relieves water shortages in Northern China, its excessive application triggers a series of environmental problems, such as heavy-metal pollution. Soil profile and river sediment profile samples from the sewage irrigation area (SIA) were collected by selecting the farmlands in which sewage irrigation activity has been reported since the 1960s, around Huiji River (HJR) and Huafei River (HFR) in Kaifeng, Henan Province, China, as research areas. In this study, the total amount of heavy metals (Cr, Cd, Pb, Mn, Zn, and Ni) and the heavy-metal speciation analysis using the modified BCR sequential extraction method were used to evaluate the impacts of wastewater on agricultural soils and the potential risk. Furthermore, the least contaminated Cr (VI) was selected for the study of adsorption characteristics to determine the environmental capacity of soils for heavy metals when the composition of wastewater changes under long-term effluent irrigation conditions. The results show that: (1) the concentrations of heavy metals in soil continuously decreased with depth, while the opposite was observed in sediment, reflecting the continuous improvement in water quality over the historical period; (2) In the topsoil, the mean concentrations (mg·kg−1) in rank order are as follows: Mn (588.68) > Zn (284.21) > Pb (99.76) > Cr (76.84) > Ni (34.71) > Cd (3.25), where Cd exceeded the control value by 3.15 times around HFR, and sediment samples also showed higher heavy metal concentrations in HFR than in HJR; (3) Speciation distribution and risk assessment code (RAC) indicate that Mn and Cd were at medium risk and that Cd warrants attention due to its being a non-essential toxic element in humans; (4) The adsorption rates of soil in various layers in different profiles within SIAs for Cr (VI) gradually increased with the increasing initial content of Cr (VI). Among the three isothermal adsorption models, the fit result obtained by the Langmuir equation was superior to those obtained by the Freundlich equation and the linear equation.