Low Health Risk Research Articles

Source identification and human health risk to polychlorinated biphenyls in public parks and playground surface soils, southern zone of Ghana.

Polychlorinated biphenyls (PCBs) constitute a typical example of persistent organic pollutants (POPs) that have been detected globally in most environmental media. Soil serves as a critical reservoir for PCBs. This research is aimed at evaluating the potential exposure and associated health risks posed by soil-laden PCBs to humans during outdoor activities on public playgrounds and parks within the southern zone of Ghana where limited studies have been undertaken. Surface soils collected from 56 sites were processed and analyzed for seven indicator PCBs in soil particle sizes less than 63µm. A multi-residual analytical approach for the simultaneous analysis of PCBs and polycyclic aromatic hydrocarbons (PAHs) via gas chromatography tandem mass spectrometry was utilized. The results indicated that the concentration of PCBs ranged from 0.26 to 24.00µg/kg with an average total concentration of 1.86 ± 3.23µg/kg which is below the environment guideline threshold of 1.3mg/kg stipulated by the Canadian Council of Ministers for residential playgrounds/parkland soils. Multivariate analysis showed that the sources of the PCBs could be attributed predominantly to historical release, atmospheric transfer, and deposition. The excess lifetime cancer risks posed to children and adults are less than 10-6 thereby implying the existence of low carcinogenic health risk to the human populace within the southern zone of Ghana. Thus, the conduct of outdoor activities at the public playgrounds/parks within these highly populated areas poses no significant risk to human health.

Chemical Migration from Reusable Plastic Bottles: Silicone, Polyethylene, and Polypropylene show Highest Hazard Potential in LC-HRMS Analysis

Estimating the chemical hazards of drinking water stored in reusable plastic bottles is challenging due to the numerous intentionally and unintentionally added chemicals. To address this, we developed a broad screening strategy using evaporation enrichment and liquid chromatography high-resolution mass spectrometry (LC-HRMS) to evaluate migration of non-volatile chemicals from various reusable plastic bottles. The study analyzed a wide range of materials, revealing significant variability in chemical profiles across different bottle types. Over 70% of nearly 1,000 unknown compounds were unique to specific bottles. Silicone, HDPE, LDPE, and PP bottles showed the highest migration rates, with silicone releasing the most unknowns, but also phthalates and plasticizers. PP bottles exhibited concerning migration of clarifying agents and bisphenol A derivatives. In contrast, PS, PET, PETG, and PCTG had minimal migration, indicating lower health risks. These findings highlight the need for comprehensive assessments of plastic materials to improve consumer safety.

Bioinsecticides based on neem (Azadirachta indica) and rue (Ruta graveolens) against Agrotis ipsilon

Agrotis ipsilon is an important pest of several crops, where it causes damage to various parts of the plant such as stems, roots, leaves and tubers. Due to the growing demand for controlling these pests, there is a constant need for new products as the organisms acquire resistance after continuous contact. And this also generates a demand for bioinsecticides, which normally pose a lower health risk and are less harmful to the environment. Among the plants commonly used as insecticides are neem and rue, which have already been studied for several pests, although never together. This work aimed to determine the insecticidal activity of a natural insecticide derived from a mixture of neem and rue, commonly used in the region of Senhor do Bonfim-BA against A. ipsilon. Four different solutions were prepared, containing a) 20 neem leaves, 10 rue leaves and 5 A. ipsilon caterpillars, b) 20 neem leaves and 10 rue leaves, c) 20 neem leaves and d) 10 rue leaves. Water was tested as control. In the tests carried out, both the mixture popularly used in the region, containing neem, rue, and A. ipsilon caterpillars, as well as the solution containing only neem and rue had good results, killing all caterpillars in 72 hours. Isolated plant extracts did not obtain good results, only delaying the formation of pupae for neem extracts. Therefore, the mixture of Neem and Rue showed good insecticidal potential against A. ipsilon, with much higher activity than its isolated components.

Spatial distribution and risk assessment of perchlorate in raw cow milk from China

Perchlorate is a ubiquitous environmental contaminant worldwide, recognized as an emerging thyroid toxicant. This study focused on the pollution status, spatial distribution, possible sources of perchlorate in raw cow milk collected from 155 dairy farms in China, as well as the health risk of exposure to perchlorate through dairy products. The results showed that the detection rate of perchlorate in raw milk was 100% with the mean of 15.9 μg/kg, indicating the ubiquitous contamination of perchlorate in raw milk from China. The simulation of spatial distributions indicated that the levels of perchlorate in raw milk were spatially correlated, and relatively high levels of perchlorate exist in certain parts of Beijing-Tianjin-Hebei, Shanxi, Henan, and Zhejiang, suggesting potential environmental perchlorate contamination in these regions. A positive correlation was found between the perchlorate level in milk and the perchlorate level in feed, indicating the transfer process of perchlorate from feed to milk. The hazard quotient (HQ) values of exposure to perchlorate by dairy products ranged between 0 and 2.14, with the mean of 0.0188 and P95 of 0.101, indicating relatively low health risk to perchlorate through dairy products. To our knowledge, this is the first nationwide study on the spatial distribution and risk assessment of perchlorate in raw cow milk from China.

Microplastic and associated emerging contaminants in marine fish from the South China Sea: Exposure and human risks

Microplastics can act as vectors of chemical contaminants in aquatic environments, but the extent to which this phenomenon contributes to chemical exposure in marine organisms remains poorly understood. We investigated the occurrence of microplastics and emerging contaminants (ECs), including antibiotics and per- and polyfluoroalkyl substances (PFAS) in 14 marine fish species. Microplastics were detected in all marine fish species, mainly in the gastrointestinal tract. Fluoroquinolones and tetracyclines were the dominant antibiotics in fish muscles with maximum concentrations of 24.84 and 26.95 ng g−1 ww, while perfluorooctanesulfonic acid (PFOS, 0.039–0.95 ng g−1 ww) was the dominant component in the PFAS profile. Fish with more microplastics had significantly higher concentrations of fluoroquinolones and perfluoroalkyl acids than fish with less microplastics (p < 0.05), but the correlation was not observed in other chemicals. Structural equation modeling revealed the contribution of microplastics in fish on the level of ECs contamination. The health quotient value indicated the low health risk of single compounds via fish consumption to humans; however, the combined risk of microplastics and ECs still needs to be considered. This work highlights the link between microplastics with associated ECs ingested by aquatic organisms and the human health risk of consuming polluted seafood.

Psychomodulatory substances: New legislative framework for control of psychoactive substances in Czechia

This article challenges drug prohibition advocated by UN conventions as the prevailing regulatory model for psychoactive substances, highlighting its ineffectiveness, harmfulness and outdated nature. At the same time, the conventions exclude some psychoactive substances from international regulation, leaving control to individual countries. Presenting an innovative approach, this article outlines an approach to the legal regulation of psychomodulatory substances (psychoactive substances with low health and societal risk) in non-medical contexts. Acknowledging the potential benefits of such psychoactive substances and balancing them with potential harms, it suggests stringent rules for marketing, safety, and preventing sales to minors. This approach aims to quell illicit markets, safeguard vulnerable populations, and encourage controlled use. Through a case study of the Czech Republicʼs introduction of a new category of psychomodulatory substances, this article showcases a paradigm shift from the prevailing repressive approach to drug regulation. This adaptive model effectively navigates the regulatory void, offering a viable alternative to the UNʼs prohibition framework.

Investigation of insecticide residues in fig and health risk assessment

This study aimed to detect insecticide, acaricide, and nematicide residues in 92 fresh and 50 dried fig samples collected from locations with intensive fig, Ficus carica L. (Rosales: Moraceae) production in Aydın, Türkiye in 2022. The analysis method was validated according to SANTE 11312/2021 guidelines. The recoveries ranged between 70% and 120%, with repeatability (RSDr) and within-laboratory reproducibility (RSDwR) ≤ 20% and expanded measurement uncertainties below 50% for all insecticides indicating satisfactory analytical performance. In total, 114 different insecticides were screened, revealing residues in 27 samples. Bifenazate was detected in 13 samples, etoxazole in 3 samples, spiromesifen in 5 samples, and both bifenazate and spiromesifen in 6 samples. No detectable residues were found in the dried fig samples. All samples in which bifenazate was detected were above the European Union Maximum Residue Limits (EU-MRL). Etoxazole and spiromesifen, unauthorized in figs, showed etoxazole residues above EU-MRLs, while spiromesifen residues were below EU-MRLs. The acute and chronic health risk indices for the insecticides were found to be below 1, indicating low health risks associated with fig consumption. The risk assessment suggests that fig consumption is safe for consumers.

Ecological and health risk assessment of heavy metals in interior dust from college campus.

Contamination of college campus dust with heavy metals and the calculation of their ecological and health risks to the students and staff did not receive much attention except in recent years. This study aims to assess the ecological and human health risks of Cd, Cr, Cu, Pb, and Zn in interior dust of College of Science/University campus. An atomic absorption spectrophotometer was utilized to estimate the samples that were collected from 46 locations of the college campus including: classrooms, offices, and laboratories. The Pb, Cu, Cr and Zn metals in the interior dust of the College of Science pose low potential ecological risk, whereas Cd generates medium potential ecological risk. The gained results showed that the student and staff of the College are exposed to low non-cancerous health risks (HI < 1) caused by Cd, Cr, Cu, Pb, and Zn in interior dust. The total lifetime carcinogenic risks (TLCR) of Cd, Cr, and Pb are within the acceptable safe limit (10-6-10-4). The low non-carcinogenic health risks of Cd, Cr, Cu, Pb, and Zn and that the carcinogenic health risks of Cd, Cr and Pb fall within acceptable safe limits, measured in the interior dust of the campus of the College of Science, does not mean neglecting the continuous assessment of those risks.

Quantitative tracing of typical herbicides and their metabolites in sorghum agrosystems for fate tendency and cumulative risk

Elucidating the combined exposure of agrochemicals is essential for safeguarding human health and agroecosystem safety. A rapid and high-sensitivity UHPLC-MS/MS method was developed for simultaneous quantification of nine compounds in sorghum by an assembly-line optimization process with a limit of quantitation of 0.001 mg/kg. The concentration variation of atrazine, quinclorac, fluroxypyr-meptyl and metabolites was reflected by terminal magnitudes of ≤0.0665 mg/kg. Additionally, atrazine was dealkylated to deethyl atrazine and desethyl desisopropyl atrazine at concentrations of 0.0014–0.0058 mg/kg during the sorghum harvest. Acceptable health hazardous of atrazine and quinclorac for all life cycle populations were comparatively assessed via deterministic and probabilistic models, in which atrazine gained an 83.55 % share of cumulative dietary risks. Rural residents had significantly higher risks than urban residents, and children were the most sensitive group. Despite the low health risks, combined exposure to herbicides and their metabolites should be continuously stressed, given their cumulative amplification effects.

An investigation of the mechanical strength, environmental impact and economic analysis of nano alkali-activated composite

The current study explores both the mechanical strength and life cycle assessments of fly ash (FA)-based alkali-activated concrete (AAC) with/without colloidal nano-silica (NS) addition at high and low molar concentrations of sodium hydroxide in the activator fluid (12 M and 3 M). The cradle-to-gate approach is used to establish the system boundaries for life cycle assessments (LCA). The environmental impact of AAC (with/without NS) and conventional cement concrete (CC) mixtures was determined using the ReCiPe midpoint and endpoint approaches across various impact categories. The AAC mixes with and without NS addition reduce greenhouse gas (GHG) emissions by 30 % and 25 % with respect to CC mix, respectively. Within the majority of impact categories, sodium silicate and sodium hydroxide production are the primary contributors, accounting for up to 91 %. However, in water depletion, global warming potential, and fuel depletion, the overall contribution is as high as 65 %. Also, the AAC mix with and without NS addition consumes 34 % and 14 % less electricity during its production with respect to the CC mixture. The CC mixes have almost 70 % more ecological damage and approximately 30 % more health risk than AAC with and without NS. However, the NS-modified AAC shows 20 % lower ecological and health risks than AAC without NS. The effect of resource scarcity on NS modified AAC is 50 % less than that of other mixes, including both AAC mix without NS and CC mix. In comparison to AAC without NS, the NS modified AAC demonstrates an 18 % reduced impact on resource scarcity. Finally, cost analysis demonstrates that AAC with NS is 16 % less expensive than CC, while AAC without NS is 26 % cheaper than CC. AAC containing 6 % NS inclusions exhibits environmental and economic benefits in addition to its enhanced mechanical performance, indicating its potential for widespread practical usage.

Who's behind the wheel? Work and health backgrounds of new transit bus operators.

Investigate new bus operators' (n = 293) occupational and health backgrounds to inform how transit authorities can support their future health and job success. New bus operators completed surveys and direct measurements that addressed demographics, work history, and 10 health risk factors. Participants averaged 42.76 years of age and were predominantly male (73.5%). Many (45.7%) came from minority backgrounds and most (66.3%) had no prior commercial driving experience. Transportation and material moving occupations were operators' most common prior jobs followed by protective service and sales and related occupations. Study-specific criteria classified operators as having low (49.5%), medium (37.9%), and high (12.6%) health risk levels. About half of the sample had medium-to-high health risks and most lacked commercial driving experience. Such information may help employers proactively support new bus operators' health and job success.

Prospect and Challenges of Litchi Cultivation in Northeast Region of India

The dynamics of pests affecting litchi crops have undergone changes over time, with litchi mites and bugs becoming less economically significant. However, insect pest infestations have emerged as a major constraint, causing substantial economic losses for growers. Litchi trees need to complete their post-harvest vegetative flush in a timely manner to produce a second flush in winter, which will then flower. Litchi fruit is highly perishable and temperature-sensitive, making it difficult to transport to distant markets without adequate cool chain infrastructure. The cumulative effect of biotic and abiotic factors compromises the agricultural value of this cash crop. Investigating natural defense mechanisms in litchi may uncover opportunities to enhance or induce antifungal compounds through defense elicitors. Further research could explore the applicability of these techniques in other countries, although registration issues may arise. Alternatively, other chemicals with similar benefits and lower health risks could be investigated. Additionally, the long-term effects of cincturing on fruit set and tree health warrant further investigation.

Dissipation and Dietary Risk Assessment of the Fungicide Pyraclostrobin in Apples Using Ultra-High Performance Liquid Chromatography-Mass Spectrometry.

The fungicide pyraclostrobin is the main measure used to control apple alternaria blotch in production. To evaluate the potential dietary risks for consumers, the dissipation and terminal residues of pyraclostrobin were investigated using ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS/MS). Pyraclostrobin in apples was extracted by acetonitrile with 2% ammonia and then purified using primary secondary amine (PSA) and graphitized carbon black (GCB). The method showed good linearity within the concentration range of 0.005-0.1 mg L-1, with a coefficient of determination (R2) ≥ 0.9958. The recoveries ranged from 96.0% to 103.8%, with relative standard deviations (RSDs) between 0.8% and 2.3%. The limit of quantification (LOQ) was 0.01 mg kg-1. Pyraclostrobin dispersible oil suspension was applied in 12 apple fields across China according to good agricultural practices (GAPs). In Beijing and Shandong, the dissipation of pyraclostrobin followed first-order kinetic equations, with a half-life of 11 days. The terminal residues ranged from <0.01 to 0.09 mg kg-1. The national estimated daily intake (NEDI) of pyraclostrobin was compared with the acceptable daily intake (ADI), resulting in risk quotient (RQc) of 80.8%. These results suggest that pyraclostrobin poses a low health risk to consumers under GAP conditions and according to recommended dosages.

Risk Assessment of Pulegone in Foods Based on Benchmark Dose-Response Modeling.

This study presents a new risk assessment of pulegone, a substance classified as possibly carcinogenic to humans (Group 2B) by the WHO International Agency for Research on Cancer (IARC). The analysis used data from a two-year carcinogenicity studies in rats and mice conducted by the National Toxicology Program (NTP) in 2011. Because of the absence of a no-observed adverse effect level (NOAEL) in these studies, the benchmark dose (BMD) approach was employed as an alternative risk assessment method. The lowest BMD lower confidence level (BMDL) of 4.8 mg/kg b.w./day among the eight endpoints served as the point of departure for calculating an acceptable daily intake (ADI) of 48 μg/kg b.w./day. This new ADI is significantly lower than the previously established tolerable daily intake of 0.1 mg/kg b.w./day set in 1997. The analysis also considered various genotoxicity studies, which indicate that pulegone's effects follow a nongenotoxic, thresholded mechanism. The estimated intake levels of pulegone in the European Union and USA were below the newly calculated ADI, suggesting a low health risk based on current consumption patterns.

Temporal variations in airborne PCDD/F and dl-PCB concentrations surrounding the dioxin-remediated areas in Da Nang, Vietnam, and health risk assessments.

The air pollution levels from polychlorodibenzo-p-dioxins/polychlorodibenzofurans (PCDD/Fs) and dioxin-like polychlorobiphenyls (dl-PCBs) in three residential areas located north, west, and south of the Da Nang airport were determined by using passive air samplers containing polyurethane foam (PUF) discs with 3-month sampling intervals from 2017 to 2020. The total toxic equivalents (∑TEQs) of the PCDD/Fs and dl-PCBs, using WHO2005-TEFs, were highest north of the airport (134 to 10610fg WHO-TEQ/PUF day, with an average of 1108fg WHO-TEQ/PUF day). The ∑TEQs were lower west of the airport, between 159 and 381fg WHO-TEQ/PUF day and averaged 230fg WHO-TEQ/PUF day. The lowest ∑TEQs occurred south of the airport, with ranges of 76 and 331fg WHO-TEQ/PUF day and an average of 152fg WHO-TEQ/PUF day. Construction activities, including excavation and transportation of dioxin-contaminated soil north of the airport, have increased airborne PCDD/F and dl-PCB contamination and health risks. The average daily doses of PCDD/Fs and dl-PCBs through inhalation (ADDA) for residents located north of the airport were the highest (10.9 to 3434fg WHO-TEQ/kg BW/day and average: 597fg WHO-TEQ/kg BW/day). Residents located west of the airport faced lower health risks (13-123fg WHO-TEQ/kg BW/day and average: 39fg WHO-TEQ/kg BW/day). Residents south of the airport were exposed to a minimum of 6.2-107fg WHO-TEQ/kg BW/day, with an average of 28fg WHO-TEQ/kg BW/day. The maximum and average ADDA values for residents north of the airport exceeded 10% of the tolerable daily intake (TDI) recommended by the WHO (100-400fg WHO-TEQ/kg BW/day). In comparison, all the ADDA values for residents located west and south of the airport were less than and within 10% of the TDI.

Social and emotional competencies in Portuguese incarcerated males: psychometric properties of the SEC-Q questionnaire and their relation to health risk behaviors

This study departs from the acknowledged absence of validated measures to assess social and emotional competencies in incarcerated individuals. This is a critical gap given that most available programs aimed at fostering prosocial behavior and reducing antisocial behaviors are theoretically based on enhancing these competencies. This study assessed the psychometric properties of the Social and Emotional Competencies Questionnaire (SEC-Q) in a sample of 219 Portuguese incarcerated males (M age = 37.21 years, SD = 10.61), and to explore the impact of the SEC-Q dimensions on health risk behaviors in this population. The study used confirmatory factor analysis (CFA) to examine the factor structure of the SEC-Q. The four-factor model fitted well to the data (SB χ2 = 267.75; df = 120; Robust CFI = 0.99; Robust RMSEA = 0.06), and, as expected, it includes four dimensions: self-awareness, self-management and motivation, social awareness and prosocial behavior, and decision-making. The four dimensions showed appropriate internal consistency (Cronbach’s alpha = 74–81; McDonald’s omega = 75–82). Additionally, social and emotional competencies were related to higher self-control (rs=0.45, p <.01) and lower health risk behaviors (rs = − 0.25, p <.01), supporting convergent and divergent validity. Findings from the negative binomial regression suggest that higher social awareness and prosocial behavior is related to less health risk behaviors among incarcerated males. This study is a pivotal step to promote an affordable and valid measure to assess social and emotional competencies among Portuguese justice-involved males. SEC-Q can be an important complementary measure for evaluating the effectiveness of interventions aimed at preventing criminal recidivism.

Determination and safety evaluation of metal element contents of Oviductus Ranae produced from &lt;i&gt;Rana dybowskii&lt;/i&gt; by pond culture–forest grazing relay model in Heilongjiang Province, China

The aquatic products of grazing ecological culture exhibit a strong reliance on the production environment system, which may result in heavy metal contamination. In this study, 24 elements (Ag, Al, As, Ba, Cd, Co, Cr, Cs, Cu, Fe, Ga, K, Mg, Mn, Na, Ni, Pb, Rb, Se, Sr, Tl, U, V, Zn) were determined for Oviductus Ranae (OR) from more than 1,000 individuals of Rana dybowskii produced by pond culture–forest grazing relay mode from six major production areas in Heilongjiang Province, China. Furthermore, we assessed the associated health risks. Our findings indicate that most of these 24 metal elements were detected in OR at a detection rate of 100%, with the exceptions being As (98.0%), Ga (98.0%), Co (98.0%), V (94.0%), Cd (89.0%), Pb (76.0%), Cs (74.0%), Tl (35.0%), and U (not detectable). Variations in element concentrations were significant across the six sampling sites, with characteristic elements identified to account for spatial differences. The total target hazard quotient was determined to be 0.152 in Heilongjiang Province, thereby suggesting a relatively low health risk associated with consuming OR from this region’s production systems according to existing standards and guidelines. Nevertheless, special attention is needed for monitoring the habitat environments of R. dybowskii from two sampling locations showing heightened pollution levels.

"Life as We Knew It": Continued Challenges in Getting Up-to-Date COVID-19 Vaccinations Amongst Black and Latinx Michigan Residents.

Minority communities are disproportionately impacted by COVID-19. In Michigan in 2024, 59% of Latinx residents, 46% of Black residents, and 57% of White residents have received at least one dose of the vaccine. However, just 7% of Black residents and 6% of Latinx residents report being up-to-date per CDC definition, versus 13% of White residents. Drawing from protection motivation theory, we aimed to identify barriers to COVID-19 vaccination. Interviews with 24 Black and 10 Latinx Michigan residents self-reported as not up-to-date (n = 15) or up-to-date (n = 19) on COVID-19 vaccines were conducted in 2022-2023. We used a community-based participatory approach in collaboration with 16 leaders from 15 organizations to develop research questions, interview protocols, and methods for data collection and analysis. Thematic coding of interviews was conducted. Findings indicate participants' lack of confidence in the COVID-19 vaccine's efficacy, with those not up-to-date expressing greater doubt. Participants were also concerned about vaccine benefits versus risks, safety, and side effects. Distrust in medicine, confusion about public health guidelines, and conspiracy theories were often reported. Younger unvaccinated individuals cited low health risk as reason to remain unvaccinated. Many participants felt that health education, especially through medical professionals, was beneficial. There is great need for more data to make informed decisions given ongoing lack of understanding of the public health benefits of COVID-19 vaccination. Identifying drivers of vaccine uptake, particularly boosters, in communities of color and developing age-appropriate and culturally responsive interventions to increase vaccination rates are of utmost importance.

Derivative spectrophotometric method for simultaneous determination of ascorbic acid and folic acid in the pharmaceutical formulation; Comparative greenness assessment

Ascorbic acid and folic acid are frequently included together in multivitamin pharmaceutical products due to their complementary roles in maintaining human health. The quality and efficiency of supplements can vary depending on the manufacturer and the specific ingredients used, which are vital factors to consider. This research presents the development and validation of a simple, sensitive, accurate, and environmentally friendly derivative spectrophotometric technique utilizing the zero-crossing method for the simultaneous determination of ascorbic acid and folic acid, both in their pure form and in pharmaceutical formulations. The derivative spectrophotometry technique demonstrated measurable amplitude and substantial linearity for both analytes. At the zero-crossing points of folic acid (249.6 and 281 nm), ascorbic acid showed a measurable amplitude with a linear range of 0.17–12.0 μg/mL and 0.37–12 μg/mL, and detection limits of 0.057 μg/mL and 0.121 μg/mL, respectively. Conversely, folic acid displayed an observable amplitude at the zero-crossing point of ascorbic acid (265.6 nm) with a linear range from 0.26 to 15.0 μg/mL and a detection limit of 0.088 μg/mL.The greenness of the proposed derivative spectrophotometric method was evaluated using the White Analytical Chemistry (WAC) framework and the Green Analytical Procedure Index (GAPI). The method scored highly in both evaluations, confirming its minimal environmental impact and alignment with the principles of Green Analytical Chemistry. The GAPI assessment highlighted low environmental and health risks throughout the analytical process, making this method a green and sustainable choice for the simultaneous determination of ascorbic acid and folic acid. The method was successfully applied to synthetic laboratory mixtures and formulated tablets, showing excellent precision, accuracy, and recovery, while also being environmentally friendly.

Investigating the environmental capacity of soil heavy metals and its determinants in agro-pastoral regions of the qinghai-tibetan plateau.

Environmental capacity (EC) serves as the basis for environmental planning and management, as a key indicator for assessing environmental risk and quality, and as a foundation for achieving sustainable development. Studies on EC typically address agricultural or urban rather than pastoral areas, with few examining agro-pastoral areas. The EC of the Tibetan Plateau is particularly important, considering its importance as an agricultural area and ecological reserve. To address this gap, the Qingshizui area in Menyuan County, a typical agro-pastoral area on the Tibetan Plateau, was selected to quantify soil EC and its spatial distribution. In terms of the dynamic and static annual soil EC for this region, the heavy metals were ranked as follows, in ascending order: Cd, Hg, Co, As, Sb, Ni, Cu, Pb, Cr, and Zn. Most of the areas with high residual EC were in the west. For the 10 heavy metals, residual EC was significantly affected by geological background. For all the heavy metals except Zn and Hg, residual EC was significantly affected by soil type. The heavy metal elements in the agro-pastoral area's soil are mildly enriched, suggesting minimal human impact. The composite EC index of this soil is 0.98, indicating an intermediate EC and low health risk. This study underscores that integrating agriculture and pastoralism can optimize land use and mitigate ecological pressures associated with these practices when done separately. Our research provides valuable insights for resource optimization, environmental conservation, and enhancing the welfare of farmers and herders in the Qinghai-Tibet region.