Cadmium contamination in a soil-rice system and the associated health risk: An addressing concern caused by barium mining

Comparative physiological and transcriptomic analyses reveal enhanced mitigation of cadmium stress in peanut by combined Fe3O4/ZnO nanoparticles

Cadmium (Cd) pollution poses a significant threat to food safety and human health. Foliar spraying of nanomaterials has been widely used to mitigate Cd stress in agriculture. However, the effects and synergistic mechanisms of various nanomaterial combinations on Cd resistance remain unclear. This study compared the impacts of Fe3O4 nanoparticles (NPs), ZnO NPs, and their combinations at different concentrations (50-400 mg/L) on the growth and physiology of peanuts under Cd-stress. Results showed that combined-NPs reduced Cd accumulation and enhanced plant growth more effectively than single-NPs. Specifically, the concentrations of Cd in roots and shoots were reduced by 52.13 % and 47.83 %, respectively, while biomass increased by 42.86 % for roots and 100.17 % for shoots. A concentration of 150 mg/L of combined NPs was optimal, reducing root Cd concentration from 0.619 mg/g to 0.245 mg/g and shoot from 0.187 mg/g to 0.148 mg/g. Transcriptomic analysis revealed that combined NPs upregulated oxidative stress-related genes (GST23, POD2) to strengthen antioxidant defenses. Simultaneously, they also downregulated metal transports (ABCC2, Nramp2, ABCG29, ABCG2), potentially limiting Cd uptake. These findings reveal the synergistic mechanism of enhancing antioxidant systems and regulating metal transport pathways, offering a new strategy to develop combined nano-fertilizers that combat Cd pollution in similar crops.

Foliar application of Fe-fulvic acid: A strategy to reduce heavy metal accumulation and enhance nutritional quality

Pepper is a key agricultural crop susceptible to accumulating heavy metals like cadmium (Cd) and barium (Ba), posing significant health risks. To address these issues, this study investigated the effects of foliar applications of fulvic acid (FA), Zn-fulvic acid (Zn-FA), and Fe-fulvic acid (Fe-FA) on Ba and Cd uptake in pepper tissues, as well as their impact on nutritional quality, biomass, and leaf enzyme activity. Results indicated that Fe-FA application significantly reduced Cd and Ba in pepper fruit by 25 % and 93 %, respectively. Additionally, Fe-FA enhanced pepper growth, increasing vitamin C and phenolic compounds by 136 % and 13 %, respectively. Metabolomics analysis revealed that Fe-FA application up-regulated 857 metabolites and down-regulated 1045 metabolites. Furthermore, Fe-FA primarily influenced amino acid, carbohydrate, and lipid metabolism, promoting pepper growth. These findings suggest that Fe-FA foliar application offers a promising strategy for reducing Ba and Cd accumulation in pepper fruits while enhancing its nutritional quality.

Co-foliar application of zinc and nano-silicon to rice helps in reducing cadmium exposure risk: Investigations through in-vitro digestion with human cell line bioavailability assay

Foliar application of zinc (Zn) or silicon nanoparticles (Si-NPs) may exert regulatory effects on cadmium (Cd) accumulation in rice grains, however, their impact on Cd bioavailability during human rice consumption remains elusive. This study comprehensively investigated the application of Zn with or without Si-NPs in reducing Cd accumulation in rice grains as well to exactly evaluate the potential risk of Cd exposure resulting from the rice consumption by employing field experiment as well laboratory bioaccessibility and bioavailability assay. Sole Zn (ZnSO4) or in combination with Si (ZnSO4 +Si and ZnO+Si) efficiently lowered the Cd concentration in rice grains. However, the impact of bioaccessible (0.1215-0.1623 mg kg-1) and bioavailable Cd (0.0245-0.0393 mg kg-1) during simulated human rice consumption depicted inconsistent trend. The straw HCl-extractable fraction of Cd (FHCl-Cd) exhibited a significant correlation with total, bioaccessible, and bioavailable Cd in grains, indicating the critical role of FHCl-Cd in Cd accumulation and translocation from grains to human. Additionally, foliar spraying of Zn+Si raised the nutritional value of rice grains, leading to increased protein content and reduced phytic acid concentration. Overall, this study demonstrates the potential of foliar application of ZnSO4 +Si in mitigating the Cd levels in rice grains and associated health risks upon consumption.

Effects of foliar application of Zn combined with organic matters on Cd accumulation and its chemical forms in rice

Rice consumption is a key Cd exposure pathway, which poses a health risk to humans. Reducing cadmium (Cd) concentrations in rice remains challenging. In this study, a pot experiment was conducted to examine the effects of foliar spray of Zn combined with organic matters (including Zn-lysine (Zn-Lys), Zn-fulvic acid (Zn-FA), Zn-amino acid (Zn-AA), and Zn combined with glutathione (Zn + GSH)) on Cd accumulation in rice grains. Compared with the control group, all treatment groups exhibited reduced Cd concentration in rice grains, while improving plant growth, and reducing Cd transport from other tissues to the grains. Zn-FA was found to be the most effective fertilizer, which considerably reduced Cd concentrations in grains from 0.77 ± 0.068 to 0.14 ± 0.021 mg/kg and yielded reductions of up to 81%, which is within the Chinese food maximum tolerable limit of 0.2 mg/kg. Furthermore, the analysis of the chemical forms of Cd of rice tissues indicated that the treatment groups had increased proportions of integrated with pectates and protein in the stems. Except for the group treated with Zn-Lys spray, the percentages of undissolved Cd phosphate in the leaves were increased in all treatment groups, which reduced Cd toxicity to rice plants. The foliar application of Zn combined with organic matters may be a promising strategy to decrease Cd concentration in rice grains cultivated in severely Cd-contaminated agricultural soil, particularly in the karst area in southwest China with limited available cultivable agricultural land.

Potentially harmful elements pollute soil and vegetation around the Atrevida mine (Tarragona, NE Spain)

Mining activity is one of the main sources to pollute soil, water and plants. An analysis of soil and plant samples around the Atrevida mining area in Catalonia (NE Spain) was preformed to determine potentially harmful elements (PHEs). Soil and plant samples were taken at eight locations around the mining area. The topsoil (0-15 cm) samples were analysed for physico-chemical properties by standard methods, by ICP-MS for Cd, Co, Cr, Cu, Fe, Ni, Pb and Zn, and were microwave-digested. Plant, root and shoot samples were digested separately, and heavy metals were analysed by AAS. Translocation factor (TF), biological concentration factor (BCF) and biological accumulation factor (BAF) were determined to assess the tolerance strategies developed by native species and to evaluate their potential for phytoremediation purposes. Soil pH was generally acid (5.48-6.72), with high soil organic matter (SOM) content and a sandy loamy or loamy texture. According to the agricultural soil values in southern Europe, our PHEs concentrations exceeded the toxicity thresholds. The highest root content of the most studied PHEs appeared in Thymus vulgaris L. and Festuca ovina L., while Biscutella laevigata L. accumulated more PHEs in shoots. The TF values were > 1 in B. laevigata L., but BAF obtained < 1, except Pb. B. laevigata L., and can be considered potentially useful for phytoremediation for having the capacity to restrict the accumulation of large PHEs amounts in roots and Pb translocation to shoots.

Derivation and validation of soil cadmium thresholds for the safe farmland production of vegetables in high geological background area

Excessive dietary intake of cadmium (Cd) poses toxicity risks to human health, and it is therefore essential to establish accurate and regionally appropriate soil Cd thresholds that ensure the safety of agricultural products grown in different areas. This study investigated the differences in the Cd accumulation in 32 vegetable varieties and found that the Cd content ranged from 0.01 to 0.24 mg·kg^-1, and decreased in the order of stem and bulb vegetables > leafy vegetables > solanaceous crops > bean cultivars. A correlation analysis and structural equation model showed that pH, soil organic matter, and the cation exchange capacity had significant effects on Cd accumulation in the vegetables and explained 72.1 % of the variance. In addition, species sensitivity distribution (SSD) curves showed that stem and bulb vegetables were more sensitive to Cd than other types of vegetables. Using the Burr Type III function for curve fitting, we derived Cd thresholds of 6.66, 4.15, and 1.57 mg·kg^-1 for vegetable soils. These thresholds will ensure that 20 %, 50 %, and 95 % of these vegetable varieties were risk-free, respectively. The predicted threshold of soil Cd was more than twice that of China's current National Soil Quality Standard (GB 15618-2018) for Cd values. Therefore, soil scenarios and cultivars should be considered comprehensively when determining farmland soil thresholds. The present results provide a new model for setting soil Cd criteria in high geological background areas.

Induction of resilience strategies against biochemical deteriorations prompted by severe cadmium stress in sunflower plant when Trichoderma and bacterial inoculation were used as biofertilizers

Background

Cadmium (Cd) is a highly toxic heavy metal. Its emission is suspected to be further increased due to the dramatic application of ash to agricultural soils and newly reclaimed ones. Thereby, Cd stress encountered by plants will exacerbate. Acute and chronic exposure to Cd can upset plant growth and development and ultimately causes plant death. Microorganisms as agriculturally important biofertilizers have constantly been arising as eco-friendly practices owing to their ability to built-in durability and adaptability mechanisms of plants. However, applying microbes as a biofertilizer agent necessitates the elucidation of the different mechanisms of microbe protection and stabilization of plants against toxic elements in the soil. A greenhouse experiment was performed using Trichoderma harzianum and plant growth-promoting (PGP) bacteria (Azotobacter chroococcum and Bacillus subtilis) individually and integrally to differentiate their potentiality in underpinning various resilience mechanisms versus various Cd levels (0, 50, 100, and 150 mg/kg of soil). Microorganisms were analyzed for Cd tolerance and biosorption capacity, indoleacetic acid production, and phosphate and potassium solubilization in vitro. Plant growth parameters, water relations, physiological and biochemical analysis, stress markers and membrane damage traits, and nutritional composition were estimated.

Results

Unequivocal inversion from a state of downregulation to upregulation was distinct under microbial inoculations. Inoculating soil with T. harzianum and PGPB markedly enhanced the plant parameters under Cd stress (150 mg/kg) compared with control plants by 4.9% and 13.9%, 5.6% and 11.1%, 55.6% and 5.7%, and 9.1% and 4.6% for plant fresh weight, dry weight, net assimilation rate, and transpiration rate, respectively; by 2.3% and 34.9%, 26.3% and 69.0%, 26.3% and 232.4%, 135.3% and 446.2%, 500% and 95.6%, and 60% and 300% for some metabolites such as starch, amino acids, phenolics, flavonoids, anthocyanin, and proline, respectively; by 134.0% and 604.6% for antioxidants including reduced glutathione; and by 64.8% and 91.2%, 21.9% and 72.7%, and 76.7% and 166.7% for enzymes activity including ascorbate peroxidase, glutathione peroxidase, and phenylalanine ammonia-lyase, respectively. Whereas a hampering effect mediated by PGP bacterial inoculation was registered on levels of superoxide anion, hydroxyl radical, electrolyte leakage, and polyphenol oxidase activity, with a decrease of 0.53%, 14.12%, 2.70%, and 5.70%, respectively, under a highest Cd level (150 mg/kg) compared with control plants. The available soil and plant Cd concentrations were decreased by 11.5% and 47.5%, and 3.8% and 45.0% with T. harzianum and PGP bacterial inoculation, respectively, compared with non-inoculated Cd-stressed plants. Whereas, non-significant alternation in antioxidant capacity of sunflower mediated by T. harzianum action even with elevated soil Cd concentrations indicates stable oxidative status. The uptake of nutrients, viz., K, Ca, Mg, Fe, nitrate, and phosphorus, was interestingly increased (34.0, 4.4, 3.3, 9.2, 30.0, and 1.0 mg/g dry weight, respectively) owing to the synergic inoculation in the presence of 150 mg of Cd/kg.

Conclusions

However, strategies of microbe-induced resilience are largely exclusive and divergent. Biofertilizing potential of T. harzianum showed that, owing to its Cd biosorption capability, a resilience strategy was induced via reducing Cd bioavailability to be in the range that turned its effect from toxicity to essentiality posing well-known low-dose stimulation phenomena (hormetic effect), whereas using Azotobacter chroococcum and Bacillus subtilis, owing to their PGP traits, manifested a resilience strategy by neutralizing the potential side effects of Cd toxicity. The synergistic use of fungi and bacteria proved the highest efficiency in imparting sunflower adaptability under Cd stress.

Assessment of Cd Pollution in Paddy Soil-Rice System in Silver Mining-Affected Areas: Pollution Status, Transformation and Health Risk Assessment

Mining activities are one of the main contamination sources of Cd in soil. However, the information about the influence of silver mining on Cd pollution in soil in mining-affected areas is limited. In the present study, sixteen paired soil and rice grain samples were collected from the farmland along the Luxi River nearby a silver mine in Yingtan City, Jiangxi Province, China. The total, bioavailable, and fraction of Cd in soil and Cd content in rice grain were determined by inductively coupled plasma mass spectrometry. The transformation of Cd in the soil-rice system and potential health risk via consumption of these rice grains were also estimated. The results showed that Cd concentration in these paddy soils ranged from 0.21 to 0.48 mg/kg, with the mean Cd concentration (0.36 mg/kg) exceeded the national limitation of China (0.3 mg/kg, GB 15618-2018). Fortunately, all these contaminated paddy soils were just slightly polluted, with the highest single-factor pollution index value of 1.59. The DTPA- and CaCl₂-extractable Cd in these paddy soils ranged from 0.16 to 0.22 mg/kg and 0.06 to 0.11 mg/kg, respectively, and the acid-soluble Cd occupied 40.40% to 52.04% of the total Cd, which was the highest among different fractions. The concentration of Cd in rice grain ranged from 0.03 to 0.39 mg/kg, and the mean Cd concentration in rice grain (0.16 mg/kg) was within the national limitation of China (0.2 mg/kg, GB 2762-2017). The bioaccumulation factor of Cd in rice grain ranged from 0.09 to 1.18, and its correlation with various indicators was nonsignificant (p < 0.05). Health risk assessment indicated that the noncarcinogenic risk for local rice consumers was within the acceptable range, but the carcinogenic risk (CR) was ranging from 1.24 × 10^-2 to 1.09 × 10^-3 and higher than the acceptable range (1.0 × 10^-4), indicating that the local rice consumers suffered serious risk for carcinogenic diseases. The results of the present study can provide reference for safety production of rice in silver mining-affected areas.

Rhizobium rhizogenes-mediated root proliferation in Cd/Zn hyperaccumulator Sedum alfredii and its effects on plant growth promotion, root exudates and metal uptake efficiency

In this study, Rhizobium rhizogenes-mediated root proliferation system in Sedum alfredii has been established. Twenty strains of R. rhizogenes were screened for root proliferation. A significant difference (P < 0.01) was observed in plant morphological characters under influence of different bacterial strains. The highest root fresh weight (3.236 g/plant) was observed with strain AS12556. Furthermore, significant difference (P < 0.05) was observed in the chemical composition of organic acids, Tartaric acid (TA), Succinic acid (SA), Malic acid (MA), Citric acid (CA) and Oxalic acid (OA), pH, Total Nitrogen (TN), Total Organic Carbon (TOC) and soluble sugars in root exudates with different R. rhizogenes mediated roots. Furthermore, a series of hydroponics experiments were conducted with varying concentrations of Cd (25, 50 and 75 µM) and Zn (100, 200 and 500 µM) to assess the phytoextraction efficiency of proliferated roots with Rhizobium. Several plants with proliferated roots showed enhanced growth and improved metal extraction efficiency. Five strains (LBA 9402, K599, AS12556, MSU440 and C58C1) were identified as potential strains for root proliferation in Sedum alfredii. R. rhizogenes strain AS12556 improved Cd/Zn phytoextraction by exogenous production of phytochemicals to promote root proliferation, improved shoot biomass, lowered oxidative damage and enhanced phytoextraction efficiency in S. alfredii. Therefore, it has been selected as a potential microbial partner of S. alfredii to develop extensive rooting system for better growth and enhanced phytoremediation potential. Results suggest that R. rhizogenes mediated root proliferation system can be used for optimizing metal extraction from contaminated soils.

Spatial distribution and main controlling factor of cadmium accumulation in agricultural soils in Guizhou, China

A large-scale investigation was conducted on the cadmium (Cd) content in the farmland soils of Guizhou to explore the spatial variation in soil Cd content, identify the main factors responsible for causing Cd pollution, and determine the zonation of Cd pollution. Multivariate statistical analysis, geographic information system (GIS) analysis, and decision tree methods were used to study the distribution, spatial variation, and pollution partitioning of Cd and the factors influencing the Cd accumulation in agricultural soils of the Guizhou province. Areas with high Cd content in agricultural soil were found to be concentrated in the high-altitude areas in the western region of Guizhou province. The results of the single factor pollution index showed that the proportion of sample sites with Cd class I (priority protection), II (security utilization), and III (strict control) in the agricultural soils of Guizhou province were 65.96%, 31.27%, and 2.77%, respectively. In high-altitude areas, the Cd content in the agricultural soils was mainly derived from the soil parent material. In contrast, mining activities and road traffic were the main factors Cd accumulation in agricultural soils in lower altitude areas.

Assessment of heavy metal accumulations and health risk potentials in tomatoes grown in the discharge area of a municipal wastewater treatment plant

Some heavy metals were detected in organs of the tomatoes grown in the discharge area of effluents of a municipal wastewater treatment plant. Also, the health risk potentials of heavy metals in the tomatoes consumed by human were investigated. The highest concentrations for Cu, Ni, Cr, Mn and Pb were followed the order of root>leaf>stem>fruit. When the bioconcentration factors values calculated for bioconcentration of metals from effluent to stem and root were examined, the highest values were determined for Cu. When translocation factors values are examined, the highest translocation from root to leaf was determined for Cd. The highest translocation from stem to leaf was determined for Pb. The estimated total exposure dose for male, female and children was listed as Zn>Mn>Cu>Cr>Ni>Pb>Cd. In terms of dietary, we can list the non-carcinogenic risks of heavy metals as children> female> male. The highest carcinogenic risk was calculated for Cr via dietary intake.

The regulatory role of root in cadmium accumulation in a high cadmium-accumulating rice line (Oryza sativa L.)

There are some key processes that regulate cadmium (Cd) accumulation in rice. Understanding the characteristics and mechanisms of Cd accumulation in high Cd-accumulating rice lines benefits for excavating relevant genes. Cd accumulation and distribution in roots of Lu527-8, a high Cd-accumulating rice line, were investigated by a hydroponic experiment, with a control of a normal rice line (Lu527-4). Lu527-8 showed significantly higher Cd concentrations in roots than Lu527-4. More than 81% of Cd in roots of two rice lines is distributed in soluble fraction and cell wall. In soluble fraction, there were more organic acids, amino acids, and phytochelatins in Lu527-8, benefiting Cd accumulation. Pectin and hemicellulose 1 (HC1), especially pectin, were main polysaccharides in cell wall. Lu527-8 showed more pectin and HC1 along with higher pectin methylesterase (PME) activity compared with Lu527-4, promoting Cd accumulation. Besides, Lu527-8 showed higher Cd translocation from root to shoot due to more amounts of ethanol-extractable Cd in roots than Lu527-4. In conclusion, specific characteristics of Cd chemical forms and subcellular distribution in roots of high Cd-accumulating rice line are important for Cd accumulation and translocation.

Cadmium exposure as a key risk factor for residents in a world large-scale barite mining district, southwestern China

Cadmium (Cd) contamination is easily generated during the mining and manufacturing of barium (Ba). In this study, concentrations of both Ba and Cd in rice, vegetables, pork, fish, drinking water, and soil samples from an active barite mining district were determined. Daily intakes of Ba and Cd, as well as corresponding health risks, were evaluated. The average total daily exposure doses of Cd were 0.0035 and 0.0012 mg/kg BW/day (geometric mean) in the mining zone (MZ) and the chemical plant zone (PZ), respectively. These values significantly exceed the provisional tolerable monthly intake (25 μg/kg BW/month, equal to 0.00083 mg/kg BW/day). Based on the daily exposure doses, vegetable consumption was the most significant Ba exposure route for residents, contributing around 66.1% of the total exposure. In contrast, rice consumption was the major Cd exposure pathway, accounting for about 85.6% of the total exposure. Although the geometric mean (0.17) and 95th percentile (P95, 0.75) of the total hazard quotient (HQ) for Ba were below the acceptable level (1), suggesting that there were no significant health effects caused by Ba exposure, Cd exposure was associated with significant health risks, with the geometric mean of the HQ (1.7) and the P95 (21) well above the acceptable limit (1), indicating the unacceptable non-carcinogenic risk of Cd exposure. In summary, high Cd exposure risk, rather than Ba, was observed for populations living in a large-scale active Ba mining area.

Microplastics with cadmium inhibit the growth of Vallisneria natans (Lour.) Hara rather than reduce cadmium toxicity

Microplastics and heavy metals are discharged into a freshwater environment either directly or via surface runoff and are largely deposited in sediments, posing risks to aquatic organisms. Few studies have thus far been devoted to the interaction of microplastics and heavy metals in sediments. Whether microplastics can affect the toxicity and accumulation of heavy metals in submerged macrophytes remains unclear. We evaluated the effects of polyvinyl chloride microplastics (PVC-MPs) and cadmium (Cd) exposure levels (0, 5, 15, and 25 mg) on Vallisneria natans (Lour.) Hara grown in sediment in a microcosm experiment for 14 d. In this study, PVC-MPs decreased the fresh weights of V. natans in the absence of Cd and markedly reduced the fresh weights at 5 and 15 mg Cd exposure levels. Moreover, PVC-MPs substantially increased the malondialdehyde (MDA) content of V. natans leaves at a Cd exposure of 25 mg. However, the PVC-MPs neither reduced the Cd concentration nor independently increased the antioxidant enzyme activities of the plants. These findings indicate that microplastics can independently, or jointly with a Cd contaminant, inhibit the growth of submerged macrophytes rather than reduce Cd toxicity. To our knowledge, this study is the first to evaluate the effects of microplastics and Cd exposure in sediments on the growth and physiological traits of submerged macrophytes, which could provide important implications for the interaction and future risk assessment of microplastics and heavy metals in sediments of freshwater ecosystems.

Dietary exposure assessment of cadmium, arsenic, and lead in market rice from Sri Lanka

Rice is frequently reported to be contaminated with heavy metals (HMs); thus, the human health risks from its consumption have received increasing attention. A total of 165 commercial rice samples from Sri Lanka were collected to determine their cadmium (Cd), arsenic (As), and lead (Pb) concentrations. The exposure risk for Sri Lankans from the estimated daily intakes (EDIs) of these toxicants was assessed. Simultaneously, non-carcinogenic and carcinogenic risks were evaluated using hazard quotients (HQs) and the hazard index (HI). The results revealed that the average levels of Cd, As, and Pb in commercial rice were 0.080 ± 0.130, 0.077 ± 0.040, and 0.031 ± 0.050 mg/kg, respectively, with ranges of 0.003-0.727, 0.019-0.217, and 0.001-0.345 mg/kg (expressed on a dry weight basis), respectively. The average EDIs of Cd, inorganic As (iAs), and Pb were 0.772, 0.490, and 0.306 μg/kg body weight (bw)/day, respectively; these were below provisional tolerable weekly intake (PTWI) values recommended by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), but iAs was above the recommended reference doses (RfDs) recommended by the United States Environmental Protection Agency (USEPA). However, approximately 25% and 75% of the Cd and iAs HQs for the Sri Lankan population, respectively, were greater than 1, suggesting a potential health risk, whereas the HQs for Pb was less than 1. Considering the additive effect, HI values of the P90, P95, P97.5, and P99 percentiles would reach 4.773, 6.458, 8.392, and 11.614, implying that intake of the combined metals might result in potential health risks.

Environmental and human health risks from cadmium exposure near an active lead-zinc mine and a copper smelter, China

Cadmium (Cd) contamination from mining and smelting operations has led to growing environmental health concerns. In this study, soil, surface water, drinking water, rice, vegetables, and biomarkers (hair and urine) were collected from local residents near an active lead-zinc mine and a copper smelter. The aim was to determine how nonferrous metal mining and smelting activities have affected the health of local residents. It was found that the Cd concentrations in most soil and rice samples exceeded the national tolerance limits of China. Dietary intakes of rice and vegetables were the two major pathways of Cd exposure to local residents, accounting for >97% of the total probable daily intake. The excessive daily intake of Cd resulted in potential non-carcinogenic risks to the local residents, especially to children living around the two areas. The mean hair and urine Cd concentrations were 0.098 ± 0.10 mg kg^-1 and 5.7 ± 3.1 μg L^-1 in the mining area, and 0.30 ± 0.21 mg kg^-1 and 5.5 ± 3.5 μg L^-1 in the smelting area, respectively. A significantly positive correlation between hair Cd concentrations and the hazard quotient (HQ) for rice ingestion indicated that rice contamination had the most critical adverse effect on local residents. Due to the high levels of environmental Cd contamination, residents of the smelting area had a much higher Cd exposure than residents of the mining area. The results suggested that nonferrous mining and smelting should not coexist with agricultural activities. Effective contamination mitigation strategies and environmental remediation should be formulated and implemented to improve the health of local residents.