Search Results (163)

Urban and rural green spaces can accumulate potentially toxic elements in topsoil and support wild mushrooms that concentrate metals. This study quantified Cd, Cu, and Zn in topsoil and naturally growing wild mushrooms from Leicestershire, UK, and evaluated spatial patterns, species- and tissue-specific accumulation, apparent soil-to-fungus transfer, and a screening dietary exposure scenario. Samples were acid-digested and analysed by ICP-MS; left-censored data were treated using R/NADA, and apparent bioconcentration factors (BCFs) were calculated from matched quadrant-level medians. Urban topsoils showed higher median Cu and Zn than rural topsoils, whereas Cd medians were similar; the SW quadrant had the highest topsoil medians for all three metals. Mushroom patterns were more heterogeneous: SW had the highest median Cd (3.15 mg kg⁻¹ dw), while NW had the highest median Cu and Zn, particularly Zn (301.29 mg kg⁻¹ dw). Agaricus bitorquis caps showed the highest median Cd and Cu among retained taxa, whereas Mycena citrinomarginata showed the highest median Zn. Cd showed the strongest apparent transfer, with a pooled urban BCF of 4.66. Median Cd concentrations were below the approximate dry-weight equivalent of the European maximum level for wild fungi, although some A. bitorquis caps exceeded it. Occasional adult-consumption estimates remained below selected health-based guidance values. Wild mushrooms provide useful complementary biomonitors of biologically expressed metal availability in public green spaces. Full article

Crops can accumulate heavy metals (HMs) from soil, leading to human exposure through dietary intake. However, the influence of interregional food trade on dietary HMs exposure remains underexplored. In this study, using data derived from existing literature, the occurrence and distribution patterns of six HMs, namely arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni), lead (Pb), and zinc (Zn), in soil and crops across China were investigated. Furthermore, the influence of food trade on human exposure to soil-derived HMs was assessed. The average total concentration of the six HMs in soil was 234.01 ± 29.54 mg/kg, while concentrations in rice and wheat were 16.06 ± 2.91 mg/kg and 22.48 ± 4.22 mg/kg, respectively. The hazard quotients (HQs) for As in rice exceeded 1 in the Central, Central Coast, South Coast, Southwest, and Northeast regions, indicating potential health risks. Interregional food trade significantly redistributed these risks. Through rice consumption, the Central and Northeast regions accounted for up to 36.78% and 45.08% of the daily intakes of As and Cd in other regions, respectively. Similarly, through wheat consumption, the Central and Southwest regions accounted for up to 51.33% and 25.97% of the daily intakes of As and Cd, respectively. This redistribution is largely attributed to the concentration of major crop production in the Central, Northeast, and Southwest regions. Overall, this study highlights the critical role of interregional food trade in modulating population health risks associated with contaminants, providing a more accurate and comprehensive assessment of dietary HMs exposure. Full article

Heavy metals, such as lead (Pb), mercury (Hg), and cadmium (Cd), pose significant public health risks even at low levels of exposure. This study examined temporal trends in blood heavy metal concentrations among Korean adults over a 12-year period using nationally representative data. We analyzed data from 17,192 adults aged ≥20 years who participated in the Korea National Health and Nutrition Examination Survey (KNHANES) Cycles 3–7 (2005, 2008–2009, 2010–2012, 2013, and 2016–2017). Blood Pb, Hg, and Cd concentrations, along with relevant covariates, were measured using standardized methods. Temporal trends and sociodemographic disparities were assessed according to sex, age, body mass index, education, income, occupation, residential area, smoking status, and alcohol consumption. All three metals exhibited statistically significant declining trends over the 12-year study period (all p for trend < 0.001). Males consistently had higher Pb and Hg concentrations than females; however, the decline in Cd was steeper in men compared to women, resulting in a reversal of the sex difference, with females having higher Cd levels than males by Cycle 7. Older adults, current smokers, blue-collar workers, and individuals with lower educational attainment had persistently elevated Pb concentrations. For Hg, individuals aged 40–59 years and alcohol consumers had the highest concentrations, whereas education, income, and residential area were not significantly associated with Hg levels. For Cd, older age, smoking, and lower educational attainment were associated with higher concentrations, with the sex difference reversing over time. These findings demonstrate the need for targeted public health strategies, including occupational Pb control, dietary guidance to reduce Hg exposure, and smoking cessation programs. Full article

Human milk (HM) is recognized as the optimal source of nutrition for infants, providing essential nutrients, bioactive compounds, and immunological protection crucial for proper growth and development. However, due to increasing environmental pollution, HM may also serve as a vector for exposure to toxic substances, including heavy metals. These contaminants originate from both current environmental exposure and long-term accumulation in maternal tissues, which may be mobilized during pregnancy and lactation. Objectives: The aim of this review was to comprehensively analyze the occurrence, sources, and determinants of heavy and toxic metals in human milk, with particular emphasis on maternal–infant transfer pathways and geographical variability of exposure. Methods: A structured narrative review with systematic literature search elements was conducted using PubMed, Scopus, and Web of Science databases. The search covered studies published between 2010 and 2025 and was limited to articles written in English. The search strategy included terms related to human milk and heavy metal exposure (Pb, Cd, Hg, As, Cr, Al). Predefined inclusion and exclusion criteria were applied, and a qualitative synthesis of environmental, dietary, physiological, and lifestyle-related determinants, as well as geographical variability, was performed. Results: The available evidence indicates that heavy metals are commonly detected in human milk worldwide, with concentrations strongly influenced by environmental pollution, maternal diet, and lifestyle factors. Under typical exposure conditions, reported concentration ranges are approximately 2–5 µg/L for lead (Pb), 1.4–1.7 µg/L for mercury (Hg), and below 1 µg/L for cadmium (Cd). However, substantially higher levels have been reported in highly contaminated regions, with extreme values exceeding 1000 µg/L for Pb and 100 µg/L for Hg in isolated cases. Key exposure pathways include contaminated food, drinking water, air pollution, and endogenous mobilization of metals stored in maternal tissues (particularly bone and adipose tissue). Significant geographical variability was observed, with higher concentrations reported in industrialized and mining regions. Infants represent a highly vulnerable population due to immature detoxification systems, increased gastrointestinal absorption, and ongoing neurodevelopment, which may amplify toxic effects even at low exposure levels. Conclusions: Although human milk remains the gold standard for infant nutrition, the presence of heavy metals highlights the need for continuous environmental monitoring and preventive strategies aimed at reducing maternal exposure. The benefits of breastfeeding clearly outweigh the potential risks; however, minimizing environmental contamination remains a critical public health priority. Future research should focus on standardizing analytical methods, improving biomonitoring strategies, and better characterizing long-term health outcomes associated with early-life exposure to toxic metals. Full article

Cadmium (Cd) is a heavy metal pollutant to which most people are exposed daily through their diet because of its presence in nearly all food types, including potatoes, vegetables, cereals, grains, legumes, shellfish, and organ meat. Cd has no physiological role or nutritional value in the body and causes toxicity to multiple tissues and organs via oxidative stress and chronic inflammation; as such, at high prevalence, it is frequently associated with diseases, notably cancer, heart disease, diabetes, osteoporosis, and chronic kidney disease. Using kidneys and bones as critical toxicity targets, current dietary Cd exposure guidelines vary from 0.21 to 0.83 μg/kg b.w./d. There is a widespread concern about these guidelines because they were based on the excretion of β₂-microglobulin (β₂M) at a rate of 300 µg/g of creatinine as an endpoint. Concerningly, rice is a staple food for over 50% of the world’s population; however, the permissible Cd level in this commodity has not been adequately addressed. This narrative review focuses on critiquing existing food standards and exposure guidelines for Cd. It discusses the threshold-based risk assessment that was used to define the no-observed-adverse-effect level (NOAEL) for Cd, when β₂M excretion was used with Cd excretion at a rate of 5.24 µg/g of creatinine being a threshold. The estimated glomerular filtration rate (eGFR) is recommended as an appropriate kidney disease endpoint. The current view around how Cd uses various transport proteins to enter and induce toxicity to its target cells are summarized. The strategies to minimize Cd accumulation and mitigate its nephrotoxicity are highlighted. Full article

Heavy metal contamination in agricultural production is a significant public health issue in Mexico, as it directly impacts food safety and population exposure through dietary intake. Available scientific evidence indicates that vegetables and other plant-derived foods can serve as significant exposure pathways for toxic elements such as arsenic, cadmium, lead, chromium, and mercury. The consumption of contaminated foods may contribute to cumulative adverse health effects, including neurological, renal, and reproductive alterations, as well as an increased risk of chronic diseases. In Mexico, risk assessment is further constrained by methodological heterogeneity across studies and by difficulties in translating scientific evidence into concrete regulatory actions. Critically, the national regulatory framework lacks specific standards establishing maximum permissible limits for heavy metals in fresh fruits, vegetables, and grains, despite their central role in the population’s diet. Regulations focus primarily on drinking water quality and selected processed foods, creating a regulatory gap in the direct control of contaminants in crops. The findings underscore the urgent need to strengthen public policies by establishing crop-specific regulatory standards, implementing systematic monitoring programs, and integrating food safety considerations more effectively into environmental, agricultural, and public health policies in Mexico. Full article

Bovine milk is a primary dietary source of nutrients and bioactive compounds. However, its safety is increasingly under threat due to contamination from mining and intensive agriculture. In the Peruvian Andes, where small-scale dairy farming coexists with historical environmental liabilities, identifying the transfer of metals into the food chain is essential for public health. This study quantifies the concentrations of lead (Pb) and cadmium (Cd) in raw milk from small-scale producers in rural districts in the province of Huancayo. Non-carcinogenic risks for populations aged 2–85 years were assessed under three consumption scenarios. Forty-five samples were analyzed using microwave plasma atomic emission spectrometry (MP-AES). The mean concentrations of Pb and Cd were 11.30 ± 18.94 µg/kg and 7.85 ± 18.11 µg/kg, respectively, which are below the maximum permissible limits (MPL). However, spatial analysis identified critical hotspots near smelters, where Pb levels reached 103 µg/kg, which is a significant exceedance of the MPL of 20 µg/kg. Toxicological modelling showed that the Hazard Index (HI) remained below the unity threshold (HI < 1) for all scenarios, ruling out immediate systemic risks. Nevertheless, the highest HI (0.78) was observed in two-year-old children in the high-consumption scenario, highlighting a localized neurodevelopmental concern. These findings emphasize the importance of georeferenced environmental monitoring and differentiated public health policies to mitigate the chronic low-level exposure to metals in vulnerable, high-altitude populations. Full article

Potentially toxic elements (PTEs) in mining-impacted wetlands can transfer from soil and water to forage and grazing livestock, resulting in dietary exposure for nearby communities. In this study, arsenic (As), lead (Pb), and cadmium (Cd) were quantified in key environmental matrices (soil, surface water, and forage) and in sheep tissues (liver, kidney, and muscle) from six georeferenced grazing sites in the Ite coastal wetland (Tacna, Peru) during the dry season. Samples were acid-digested following U.S. EPA protocols and analyzed by atomic absorption spectrometry (AAS) under QA/QC procedures (certified reference materials, blanks, duplicates, and matrix spikes); matrix-specific detection and quantification limits are reported. Arsenic dominated the contamination profile (forage: 428.6 mg kg⁻¹, dry weight; soil: 48.61 mg kg⁻¹; water: 0.97 mg L⁻¹) and was detected in sheep tissues (kidney: 0.1577 mg kg⁻¹; muscle: 0.1538 mg kg⁻¹; liver: 0.0644 mg kg⁻¹). Lead and cadmium were <LOQ in muscle and liver but were measurable in kidney (Pb: 0.0415 mg kg⁻¹; Cd: 0.0011 mg kg⁻¹). To support the interpretation of trophic transfer, screening transfer/bioaccumulation metrics (soil-to-forage, forage-to-tissue, and water-to-tissue) were calculated. Human dietary exposure was screened using estimated daily intake (EDI), hazard quotient (HQ), and margin of exposure (MOE). Because arsenic speciation was not measured, inorganic arsenic (iAs) risk was evaluated as a conservative upper bound (100% iAs) and through sensitivity scenarios (10–50% iAs). Under a high-meat-consumption scenario (300 g day⁻¹), the upper-bound assumption yielded HQ = 2.2 and MOE = 0.46; however, scenario analyses indicate that risk conclusions are highly dependent on the assumed iAs fraction. Overall, the results identify arsenic as a priority contaminant and support targeted grazing management, the provision of low-arsenic water sources, and remediation and monitoring actions to reduce exposure in vulnerable rural communities. Full article

Heavy metal contamination of foods remains a persistent global challenge for food safety and public health, driven by industrialization, mining activities, intensive agriculture, and ongoing environmental degradation. This scoping review synthesizes peer-reviewed literature on the occurrence of priority toxic metals—arsenic, cadmium, lead, mercury, and nickel—in food matrices, with emphasis on contamination pathways, analytical detection strategies, and documented human health effects. The reviewed studies reveal widespread accumulation of heavy metals in staple foods, including cereals, vegetables, seafood, and processed products, with concentrations frequently approaching or exceeding international regulatory limits, particularly in regions exposed to strong anthropogenic pressure. Conventional laboratory-based techniques, such as atomic absorption spectrometry and inductively coupled plasma methods, remain the reference standards for quantitative determination and regulatory compliance; however, their application to large-scale or continuous monitoring is often constrained by cost, infrastructure, and operational complexity. Consequently, increasing attention has been directed toward emerging detection approaches, including portable X-Ray fluorescence, Raman/SERS spectroscopy, electrochemical biosensors, electronic tongues, and in situ magnetic measurements, as complementary tools for rapid screening and field-based surveillance. Among these, environmental magnetism and in situ magnetic techniques stand out as non-destructive, low-cost proxies capable of identifying metal-associated particulate contamination linked to food production systems. Chronic dietary exposure to heavy metals is consistently associated with neurotoxicity, nephrotoxicity, carcinogenicity, and oxidative stress, underscoring the need for integrated, multi-tiered monitoring frameworks to support early detection, risk assessment, and prevention. Full article

The focus of modern livestock production is increasingly shifting toward improving animal health, welfare, and product quality through the use of natural feed ingredients. Pumpkin (Cucurbita spp.) and its seeds are of interest because they contain biologically active compounds, including tocopherols and phenolic antioxidants. This study evaluated the effects of pumpkin seed cake (PSC) in rabbit diets on blood parameters, oxidative status, and trace element distribution in tissues. Sixty Popielno White rabbits were initially assigned to three dietary groups: control (0% PSC), 5% PSC, and 10% PSC. At 90 days of age, samples from 30 rabbits (10 per group) were collected and analysed. PSC supplementation significantly increased red blood cell count, haemoglobin, haematocrit, and platelet indices (p ≤ 0.05), indicating affected haematological status. It also reduced (p ≤ 0.05) urea, triglycerides, total cholesterol, and LDL cholesterol. Antioxidant status significantly improved, as indicated by higher superoxide dismutase activity and ferric-reducing antioxidant power, together with lower malondialdehyde levels (p ≤ 0.05). Mineral analysis showed lower manganese concentrations in muscle and kidney tissues; cadmium remained low, and lead was below the detection limit in muscle and liver samples. Overall, PSC may be considered a promising feed ingredient that supports haematological status, antioxidant protection, and metabolic balance under the conditions of the present study. Full article

The term ‘superfoods’ refers to a rapidly expanding group of food products that have gained increasing global interest due to their high nutritional value and association with health-oriented dietary patterns. Many superfoods, particularly grains and seeds, are rich sources of essential minerals, plant protein, dietary fibre, and bioactive compounds, making them valuable components of gluten-free, vegetarian, and vegan diets. The aim of this study was to evaluate the elemental composition of selected superfood grains and seeds and to verify the reliability of manufacturers’ declarations. The analyses confirmed that the investigated samples possess a rich macro- and trace elemental composition, with pronounced differences among product groups. Based on median concentrations, pumpkin and hemp seeds were characterized by generally high levels of Mg, K, P, Fe, Mn, and Zn, whereas chia seeds exhibited notably elevated Ca content. In contrast, quinoa and amaranth showed comparatively lower elemental concentrations. Most of the results obtained for the analysed products are within the permissible deviation from the value declared on the packaging, as specified in the relevant EU regulations. The presence of potentially toxic elements, including Al, Pb, and Cd, was also detected. Cadmium accumulation was of particular concern in flax seeds, where all samples exceeded the limit of quantification and approached permissible levels. Principal component analysis revealed clear clustering patterns, indicating similarities between amaranth and quinoa, as well as between hemp and pumpkin seeds, while chia and flax seeds formed distinct groups. These results highlight both the nutritional potential of superfoods and the necessity for independent verification of their elemental composition. Full article

In the present study, arsenic, cadmium, lead, and manganese contamination in propolis was assessed. A total of 12 raw propolis samples were analysed using atomic emission spectrometry with inductively coupled plasma (ICP-OES) for each of the metals. The analyses revealed that the samples were contaminated with each of the following metals: arsenic (ranging from <0.21 to 0.4 ppm), cadmium (<0.008 to 0.123 ppm), lead (0.580 to 117.01 ppm), and manganese (4.22 to 47.57 ppm). Lead levels exceeded the acceptable limits for consumption. A chemometric characterization was performed, looking at the correlation between elemental contamination, showing high correlation between cadmium and manganese levels (r = 0.80). Furthermore, the samples with the highest contamination levels were in areas with high industrial and agricultural activity. A risk assessment for toxic metals indicated a risk associated with lead. While the amount of lead present in the propolis samples was deemed to pose a low carcinogenic risk, it is noteworthy that the levels of the other metals detected do not pose any discernible health risk associated with the consumption of propolis. This conclusion is crucial for understanding the safety profile of propolis as a dietary supplement or natural product. Full article

Heavy metals in agricultural systems pose a significant challenge to food security, especially in regions with long-term intensive land use. While the Pannonian Plain represents Croatia’s primary breadbasket, accounting for a significant portion of the nation’s cereal production, data on the soil-to-grain transfer of heavy metals and the associated human exposure risk are limited. The objective of this study was (i) to determine the concentrations of arsenic (As), cadmium (Cd), and lead (Pb) in agricultural soils and corresponding grains (wheat, barley, and maize) across four principal counties within the Pannonian region of Croatia; (ii) to evaluate the soil-to-grain transfer factors that varied regionally and among cereal types; and (iii) to assess the potential non-carcinogenic health risks for both adults and children highlighting differences in exposure due to body weight and consumption patterns. Soil and cereal grain samples were collected in 2019 and 2020, and metal concentrations were determined by ICP-MS after microwave acid digestion. The transfer of metals from soil to grain was estimated using the transfer factor (TF), while exposure assessment was conducted by calculating the estimated daily intake (EDI), hazard quotient (HQ), and hazard index (HI). Due to the nonlinear distribution of the data and the lack of strictly matched soil and grain samples, median metal concentrations pooled across all studied regions were used for exposure assessment. For As, a conservative approach was applied, assuming that 50% of the total As is in inorganic form. Additionally, a probabilistic risk assessment using Monte Carlo simulations was conducted to account for variability in body weight and cereal intake, providing a more comprehensive evaluation of potential exposure. The results showed differences in metal accumulation among cereal species, with wheat and barley tending to accumulate more Cd than maize, while As and Pb concentrations in grains were low for all crops studied. Although soil metal concentrations in Međimurje County were generally low, elevated TF values for As and Pb were observed, indicating enhanced soil-to-plant transfer under specific local soil conditions. In contrast, high soil metal concentrations in Slavonski Brod–Posavina County were associated with low TF values, suggesting limited bioavailability and restricted transfer to cereal grains. Both deterministic and probabilistic assessments indicated that the HQ and HI for adults and children were below 1, suggesting low non-carcinogenic risk from cereal consumption. These findings highlight pronounced regional and crop-specific differences in soil-to-plant metal transfer and confirm that low soil contamination does not necessarily imply low transfer potential, emphasizing the importance of integrated soil–plant–grain monitoring for food safety assessment. Full article

Rice (Oryza sativa L.) readily accumulates cadmium (Cd), posing dietary exposure risks in populations dependent on rice-based diets. This study investigated how sulfur (S) redox processes regulate Cd mobility in S-deficient, Cd-contaminated paddy soil under waterlogged conditions. A pot experiment was conducted with two S treatments (−S and +S, 30 mg kg⁻¹) throughout the rice growing season. S addition markedly increased pore water S²⁻ concentrations during early growth (tillering) and mid-season (booting) and suppressed the diffusion of SO₄²⁻ from non-rhizosphere to rhizosphere at later stages (filling–maturity). Consequently, Cd in soil pore water was significantly lower in +S than −S treatments at all stages. Sulfur-amended soil showed a redistribution of Cd from labile fractions (exchangeable and carbonate-bound) to more stable fractions (Fe/Mn oxide-bound). Sulfur application also altered the rhizosphere microbiome: the relative abundance of sulfate-reducing bacteria (SRB) increased at the booting and filling stages, while sulfur-oxidizing bacteria (SOB) became more dominant at maturity. Additionally, +S enhanced Cd sequestration on rice root iron plaque by 32–67% during the grain-filling and maturity stages compared to −S. Throughout the rice growing period, redox-driven shifts in the S²⁻/SO₄²⁻ ratio emerged as a key control on Cd behavior, with low pe + pH (strongly reducing conditions) promoting Cd sulfide precipitation and high pe + pH (more oxidizing conditions) causing Cd remobilization. Full article

Diet plays a central role in shaping the composition and metabolic activity of the oral microbiota, thereby influencing both oral and systemic health. Disturbances in this delicate host–microbe balance, triggered by dietary factors, smoking, poor oral hygiene, or antibiotic use, can lead to microbial dysbiosis and increase the risk of oral diseases such as periodontitis, as well as chronic systemic disorders including diabetes, cardiovascular disease, Alzheimer’s disease, and certain cancers. Among dietary contaminants, exposure to toxic heavy metals such as cadmium (Cd), lead (Pb), mercury (Hg), nickel (Ni), and arsenic (As) represents an underrecognized modifier of the oral microbial ecosystem. Even at low concentrations, these elements can disrupt microbial diversity, promote inflammation, and impair metabolic homeostasis. Saliva has recently emerged as a promising, non-invasive biofluid for monitoring nutritional status and early metabolic alterations induced by diet and environmental exposures. Salivary biomarkers, including metabolites, trace elements, and microbial signatures, offer potential for assessing the combined effects of diet, microbiota, and toxicant exposure. This review synthesizes current evidence on how diet influences the oral microbiota and modulates susceptibility to heavy metal toxicity. It also examines the potential of salivary biomarkers as integrative indicators of nutritional status and metabolic health, highlights methodological challenges limiting their validation, and outlines future research directions for developing saliva-based tools in personalized nutrition and precision health. Full article