Melamine

Toxics. 2025 Feb 25;13(3):161. doi: 10.3390/toxics13030161.

ABSTRACT

In the manufacture of infant formulas, from raw materials to the final product, the ingredients are subject to high temperatures which favor the formation of undesirable compounds, some of them from the Maillard reaction, such as 5-hydroxymethylfurfural (HMF) and acrylamide, and others from thermal processing, such as the compound 3-monochloro-1,2-propanoldiol (3-MCPD). Finally, there is also a risk that the product may be adulterated with undesirable components such as melamine and cyanuric acid. Due to the vulnerability of infants during the first stage of life, this review answers the main question: How much of these undesirable compounds are present in commercial infant formulas, and what do we know about them? Accordingly, the review is divided into three sections: (1) Maillard reaction products (HMF and acrylamide), (2) products contained in vegetable oils (3-MCPD), and (3) fraudulent and/or adulterant compounds (melamine and cyanuric acid). The objective is to report on the occurrence of HMF, acrylamide, 3-MCPD, melamine, and cyanuric acid in infant formulas in order to support more solid public health policies related to infant feeding. These undesirable compounds represent a risk to infants, possibly contributing to kidney and neurological damage and causing mutations that increase the development of childhood cancer. Therefore, it is necessary to promote breastfeeding and establish stricter controls, with scientific evidence on the effects of HMF, acrylamide, 3-MCPD, melamine, and cyanuric acid in infant formulas to reduce their short- and long-term effects on infants' health.

PMID:40137488 | PMC:PMC11946680 | DOI:10.3390/toxics13030161

Oncol Res. 2025 Feb 28;33(3):665-674. doi: 10.32604/or.2024.054487. eCollection 2025.

ABSTRACT

OBJECTIVES: Due to systematic side effects, there is a growing interest in nanoparticle formulation of anticancer drugs. Here, we aimed to synthesize poly (styrene-alt-maleic anhydride) cross-linked by melamine (PSMA/Me) and coated with magnetite nanoparticles (MNPs) PSMA/Me/Fe₃O₄. In addition, we aimed to load paclitaxel (PTX) into PSMA/Me/Fe₃O₄ for drug delivery and anticancer investigations.

METHODS: Novel PSMA/Me was synthesized via free radical copolymerization, coated with Fe₃O₄, and then used as a transporter for PTX delivery. Fabricated copolymer was characterized using SEM, TGA, and XRD techniques. Drug release rate and loading efficiency were investigated. Human ovarian cancer cells (Skov-3) and breast cancer cells (MCF-7 cells) were incubated with the serial concentration of either free PTX or PSMA/Me/Fe₃O₄/PTX for cell viability and IC₅₀ analysis for 24 and 48 h.

RESULTS: Characterization methods confirmed PSMA/Me copolymer formation. The results showed a significant encapsulation efficiency of 83%. The drug release analysis exhibited that PSMA/Me/Fe₃O₄/PTX may be considered pH-sensitive nanocarriers. PSMA/Me/Fe₃O₄/PTX reduced cell viability both dose and time-dependently (p < 0.05). IC₅₀ values of PSMA/Me/Fe₃O₄/PTX were low when compared to free PTX either 24 or 48 h post-treatment.

CONCLUSIONS: Our results indicated that PSMA/Me/Fe₃O₄/PTX was more cytotoxic than PTX in both cancer cells. Findings indicated the potential of PSMA/Me/Fe₃O₄/PTX as an anticancer nanocarrier system.

PMID:40109872 | PMC:PMC11915072 | DOI:10.32604/or.2024.054487

Ecotoxicol Environ Saf. 2025 Mar 15;293:118029. doi: 10.1016/j.ecoenv.2025.118029. Epub 2025 Mar 14.

ABSTRACT

BACKGROUND: Within the past two decades, high-profile cases of melamine (MA) exposure have raised significant toxicological concerns, particularly regarding food adulteration. While widely used as a fundamental organic chemical intermediate in various household products, MA's potential for unexpected toxicological synergy with its homolog, cyanuric acid (CA), remains a concern. This study aimed to investigate the nephrotoxicity of combined melamine and cyanuric acid (MC) exposure and its underlying mechanisms in rats through an integrative approach, combining network toxicology (NT), bioinformatics, and experimental validation.

MATERIALS AND METHODS: Rats were exposed to MC at doses of 0/0 mg/kg/day (Control) and 63/63 mg/kg/day (MC) for four weeks. Kidney pathology, injury markers, and RNA sequencing (RNA-seq) data were analyzed to identify differentially expressed genes between the two groups. Bioinformatics analysis, including pathway enrichment and immune microenvironment analysis, was conducted to elucidate the underlying mechanisms of MC-induced kidney injury. Potential target proteins were identified using ChEMBL, STITCH, and GeneCards databases, and hub genes were screened using three machine learning algorithms: LASSO regression, Random Forest, and Molecular Complex Detection. Molecular docking simulations were performed to assess the interactions between MC and the identified hub genes.

RESULTS: MC exposure resulted in severe kidney morphological and histological changes, as well as elevated levels of kidney injury and fibrosis markers. RNA-seq analysis revealed significant enrichment of immuno-inflammatory and apoptosis-related pathways in the MC group. Immune microenvironment analysis confirmed the infiltration of pro-inflammatory immune cells. Network toxicology analysis identified 20 potential targets associated with MC-induced kidney injury. Two hub genes, Ren and Casp3, were identified as key regulators of the renin-angiotensin-aldosterone system (RAAS) activation and apoptosis, respectively. Further experimental validation, including Western blotting and immunofluorescence, confirmed the upregulation of these proteins. Molecular docking simulations demonstrated strong binding affinities between MC and the two hub proteins.

CONCLUSION: MC exposure induces significant kidney injury and fibrosis. The activation of the RAAS pathway and apoptosis plays a crucial role in MC-mediated nephrotoxicity. However, additional vivo experimental validation is lacking. Future studies should focus on further exploration for the mechanism of MC-induced nephrotoxicity and more rigorous experimental validation.

PMID:40088607 | DOI:10.1016/j.ecoenv.2025.118029

J Chromatogr A. 2025 May 10;1748:465850. doi: 10.1016/j.chroma.2025.465850. Epub 2025 Mar 6.

ABSTRACT

Based on the principle that poly(thymine) ssDNA could recognize melamine (Mel) in aqueous media and the third face of Mel could be accessed by other hydrogen bonding molecules, UiO-66-NH₂ was functionalized with poly(thymine) ssDNA and as the matrix to construct three-face recognition molecularly imprinted polymers (UDMIPs). The adsorption processes of UDMIPs towards Mel were accorded to Sips model and exhibited high adsorption capacity (Q_S=10.60 mg/g) and good imprinting factor (IF=2.67). UDMIPs could reach the adsorption equilibrium within 20 min. Competitive adsorption and regeneration experiments demonstrated that UDMIPs exhibited good selectivity and reusability. The adsorption machanism was investigated by CD spectroscopy. Combined with HPLC, UDMIPs were successfully employed to detect Mel in milk samples with recovery rates ranging from 88.4 % to 94.8 %.

PMID:40086143 | DOI:10.1016/j.chroma.2025.465850

Tissue Cell. 2025 Mar 1;95:102826. doi: 10.1016/j.tice.2025.102826. Online ahead of print.

ABSTRACT

Melamine is a prevalent environmental toxicant associated with well-established toxicity on several organs. The adrenal gland is a highly dynamic organ that makes it susceptible to chemicals' toxicity. The current work investigated the adrenal histo-biochemical alterations caused by melamine exposure in rats and explored whether morin has protective potential against such adrenal toxicity. The experiment utilized 32 adult male Wistar rats randomly divided into control, morin, melamine, and melamine/morin groups. Adrenal toxicity was induced by melamine (126 mg/kg/d). Morin was used in a dose of 50 mg/kg/d. All treatments were given via oral gavage for 4 weeks. The adrenal oxidative stress markers, serum corticosterone (CORT), adrenocorticotrophic hormone (ACTH), and the mRNA expression of the steroidogenic genes; StAR (Steroidogenic acute regulatory protein), P450scc (Cholesterol side-chain cleavage enzyme), and11β-HSD1 (11β-Hydroxysteroid dehydrogenase type 1) were evaluated. Also, histological and immunohistochemical examinations of the paraffin-processed adrenal sections were performed. Melamine decreased adrenal tissue superoxide dismutase (SOD) and catalase (CAT) activities, increased adrenal malondialdehyde (MDA) levels, decreased serum CORT and increased ACTH levels, and suppressed the adrenal cortical expression of genes involved in steroidogenesis. Moreover, the inducible nitric oxide synthase (iNOS) and cysteine-aspartic acid protease-3 (caspase-3) expression were upregulated as indicated by quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) and immunohistochemistry. Besides, melamine caused remarkable adrenal histopathological changes. However, morin administration greatly repaired the adrenal injury and restored the adrenal function. Morin maintained the adrenal histoarchitecture and protected against melamine-provoked adrenal toxicity by downregulating the inflammation and the adrenal apoptotic processes and relieving the oxidative stress burden.

PMID:40056657 | DOI:10.1016/j.tice.2025.102826

Food Chem X. 2025 Feb 3;26:102254. doi: 10.1016/j.fochx.2025.102254. eCollection 2025 Feb.

ABSTRACT

Melamine contamination in food poses significant health risks including kidney stones, renal failure, making it a critical food safety concern. This study investigated the presence of melamine contamination in commercial citrus juices and its exposure through citrus juice. Samples were selected from different packaging. Melamine concentrations in commercial juice samples varied significantly, ranging from 1.732 mg/L in lemon juice to 31 mg/L in orange juice. The highest levels were found in products packaged in cardboard packaging. However, the risk assessment did not identify any risk for different ages. But, these findings highlight the need to monitor melamine levels in commercial juices.

PMID:39995402 | PMC:PMC11848499 | DOI:10.1016/j.fochx.2025.102254

Spectrochim Acta A Mol Biomol Spectrosc. 2025 May 15;333:125870. doi: 10.1016/j.saa.2025.125870. Epub 2025 Feb 8.

ABSTRACT

Non-halogenated flame-retardant Melamine (MEL), an alternative to toxic halogenated flame retardants, has been recognized as a substance of very high concern by the ECHA. Therefore, identifying MEL in plastic waste is essential for ensuring safe handling and recycling. This study presents industrial in-line quantitative identification techniques for MEL in low-density polyethylene (LDPE) and polypropylene (PP) via short-waved infrared (SWIR) hyperspectral imaging combined with machine learning. LDPE and PP samples with varying MEL loadings were compounded and characterized through elemental analysis, ATR-FTIR, TGA, and DSC. Regression on the SWIR band area ratio and principal component one was applied to the SWIR spectra to compile predictive models. The models performed equally well, demonstrating a strong correlation between measured and predicted MEL concentrations. The model based on SWIR band area ratio ranged from 0.8 to 29.8 wt% MEL in LDPE (R²_LDPE = 0.975) and 1.4 to 26.3 wt% MEL in PP (R²_PP = 0.995), while the model based on principal component one ranged from 0.8 to 29.8 wt% MEL in LDPE (R²_LDPE = 0.978) and 0.9 to 26.3 wt% MEL in PP (R²_PP = 0.988). Further, the hyperspectral in-line models perform comparably to FTIR band ratio ranging from 1.11 to 29.78 wt% MEL in LDPE and 1.40 to 26.26 wt% MEL in PP. The proposed methods can facilitate real-time monitoring of MEL concentrations in plastic and enable detection below hazardous threshold limits, which is crucial in the recycling industries.

PMID:39952067 | DOI:10.1016/j.saa.2025.125870

J Food Sci Technol. 2025 Mar;62(3):471-482. doi: 10.1007/s13197-024-06037-6. Epub 2024 Jul 21.

ABSTRACT

Zinc oxide nanoparticles (ZnO-NPs) were green synthesized using Carica papaya peel extract as a reducing agent and used to develop a novel Micro Raman Spectroscopy method to detect melamine in infant milk powder. Citrate was coated on the biosynthesized ZnO-Np, as a melamine-binding agent. SEM, AFM, TEM, FTIR, MRS, and XRD were used to confirm the morphology, size, and nature of ZnO-Np, citrate-coated ZnO-Np (ZnO-W/C), and ZnO-W/C conjugated with melamine. The zeta potential was - 43.5 mV, and the ZnO-W/C particle size ranged from 50 to 100 nm. Using MRS with a laser wavelength of 785 nm for a Raman shift ranging from 400 to 1200 cm^-1, ZnO-W/C was utilized to detect melamine. ZnO-W/C conjugated with melamine showed a Raman shift at 677 cm^-1. A linear regression model based on the Raman shift at different melamine concentrations was developed to quantify melamine in the spiked milk powder. With spiked infant milk powder, the lowest melamine detection level was 0.125 ppm. This is a sensitive and effective way to detect melamine in infant milk powder. This work suggests that ZnO-NPs, synthesized using fruit industry waste as a starting material, can serve as a diagnostic tool to ensure food safety.

SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-024-06037-6.

PMID:39917346 | PMC:PMC11794735 | DOI:10.1007/s13197-024-06037-6

J Hazard Mater. 2025 May 5;488:137379. doi: 10.1016/j.jhazmat.2025.137379. Epub 2025 Jan 26.

ABSTRACT

Mercury (II) ion (Hg^{2 +}) as highly toxic heavy metal may be accumulated in aquatic ecosystems and animals species so as to enter human body to conduct health harm. To ensure the safety of fishes food, hence, it is of great interest to evaluate the Hg²⁺ levels in different kinds of fishes as well as Hg²⁺ removal in aquaculture tailwater. In this article, a selective colormetric detection and efficient removal strategy has been developed for Hg²⁺ ions by the controlled supermolecular self-assembly of melamine (MA)-platinum (Pt) composites onto mesoporous Fe₃O₄ carriers. The resulting Fe₃O₄@MA-Pt exhibited the largely enhanced catalysis properties, which might rationally decrease in the presence of Hg²⁺ ions through the strong Pt-Hg and MA-Hg interactions. A colorimetric analysis technique based on Fe₃O₄@MA-Pt catalysis was thereby designed for detecting Hg²⁺ ions with the linear concentrations ranging from 0.010 to 1.0 μM. Moreover, Hg²⁺ levels in muscles samples of four kinds of carnivorous and omnivorous fishes were evaluated, displaying an obvious difference in order of snakehead > largemouth bass > crucian carp > silver carp. The data indicate that the carnivorous fishes should possess higher Hg²⁺ levels than the omnivorous ones, thus providing a recognizable guidance to the safety evaluation of Hg²⁺ in different kinds of fishes. Furthermore, the Fe₃O₄@MA-Pt composites with high surface-to-volume ratios were utilized to adsorb Hg²⁺ ions in aquaculture tailwater, achieving the adsorption efficiencies up to 99.73 %. Such a colorimetric analysis and removal strategy for Hg²⁺ ions may promise for aquatic food safety, clinical diagnostics, environmental monitoring, and tailwater treatments.

PMID:39874769 | DOI:10.1016/j.jhazmat.2025.137379

Ecotoxicol Environ Saf. 2025 Jan 15;290:117814. doi: 10.1016/j.ecoenv.2025.117814. Epub 2025 Jan 27.

ABSTRACT

The abrasion of melamine cleaning sponges release microplastic fibers (MPFs) into the environment, yet the potential risks remain unknown. Here, we evaluated the ingestion, elimination, and toxic effects of melamine MPFs on Daphnia magna through acute and chronic exposures. This new type of MPFs displayed different morphology (a combination of linear and branched fibers with a length ranging from 10 to 157 μm) from the widely-studied MPFs released from textiles (longer and thicker linear fibers but no branched fibers). Although the lethality of melamine MPFs to neonates was not observed upon a short-term exposure (24 h), such effect was detected when the animals were exposed for a longer period (21 d) and showed a concentration-dependent manner. The MPFs tended to aggregate in the gut of D. magna, leading to a slow elimination compared to polystyrene microspheres. The MPFs remaining in the gut triggered an elevation in the intracellular reactive oxygen species, which further induced oxidative damage and eventually death. The long-term exposure to MPFs also stimulated D. magna to produce more offspring. Our findings show the chronic toxicity of the sponges-derived MPFs to typical freshwater zooplankton and accentuate the environmental impacts related to the extensive use of the sponges.

PMID:39874685 | DOI:10.1016/j.ecoenv.2025.117814

Nanomicro Lett. 2025 Jan 27;17(1):116. doi: 10.1007/s40820-025-01646-y.

ABSTRACT

In recent decades, annual urban fire incidents, including those involving ancient wooden buildings burned, transportation, and solar panels, have increased, leading to significant loss of human life and property. Addressing this issue without altering the surface morphology or interfering with optical behavior of flammable materials poses a substantial challenge. Herein, we present a transparent, low thickness, ceramifiable nanosystem coating composed of a highly adhesive base (poly(SSS₁-co-HEMA₁)), nanoscale layered double hydroxide sheets as ceramic precursors, and supramolecular melamine di-borate as an accelerator. We demonstrate that this hybrid coating can transform into a porous, fire-resistant protective layer with a highly thermostable vitreous phase upon exposure to flame/heat source. A nanosystem coating of just ~ 100 μm thickness can significantly increase the limiting oxygen index of wood (Pine) to 37.3%, dramatically reduce total heat release by 78.6%, and maintain low smoke toxicity (CIT_G = 0.016). Detailed molecular force analysis, combined with a comprehensive examination of the underlying flame-retardant mechanisms, underscores the effectiveness of this coating. This work offers a strategy for creating efficient, environmentally friendly coatings with fire safety applications across various industries.

PMID:39865213 | PMC:PMC11769928 | DOI:10.1007/s40820-025-01646-y

Spectrochim Acta A Mol Biomol Spectrosc. 2025 Apr 5;330:125758. doi: 10.1016/j.saa.2025.125758. Epub 2025 Jan 19.

ABSTRACT

Herein, nitrogen doped carbon quantum dots (N-CQDs) were synthesized using a hydrothermal strategy. The raw materials for the preparation of N-CQDs were sourced from pumpkin and melamine. The N-CQDs suggested fascinating water solubility, favorable UV and salt resistance stability. The fluorescence quantum yield of N-CQDs was carried out to be 16.7 %. The prepared N-CQDs suggested good optical features and favorable blue fluorescence under a UV lamp (365 nm). The as-prepared N-CQDs could be employed as rapid, sensitive and promising fluorescence nanoprobes to detect nifuratel because of static quenching and inter filter effect. For nifuratel detection, the linear range of 0.5-100 μM and detection limit of 0.074 μM were obtained. Furthermore, N-CQDs were subsequently applied to determine nifuratel in river water and Yili milk samples with acceptable experiment results. Significantly, N-CQDs suggested evident temperature-sensitive characteristics and were employed as fluorescent temperature sensing nanoprobes.

PMID:39837228 | DOI:10.1016/j.saa.2025.125758

J Food Prot. 2025 Feb 26;88(3):100454. doi: 10.1016/j.jfp.2025.100454. Epub 2025 Jan 16.

ABSTRACT

Melamine, as a toxic compound, needs to be controlled in food, especially in dairy products. In this systematic study, quantities of melamine and cyanuric acid in various types of milk were investigated. A comprehensive database search was performed using the keywords pasteurized milk, milk, sterilized milk, melamine, and cyanuric acid without time limitation. A total of 24 articles related to melamine and cyanuric acid were thoroughly reviewed. The overall mean concentration of melamine in milk was estimated by meta-analysis to be 11.3 μg/L. Publication bias was not addressed in the associated assays; however, it was addressed as highly heterogeneous between studies. Subgroup analysis was carried out, and the milk type was a cause of heterogeneity. This systematic review investigated a range of melamine in milk products and discussed different analytical methods.

PMID:39826682 | DOI:10.1016/j.jfp.2025.100454

Polymers (Basel). 2024 Dec 21;16(24):3586. doi: 10.3390/polym16243586.

ABSTRACT

The issue of hazardous smoke and toxic gases released from epoxy resins (EP), which often causes casualties in real fires, has limited its application. Therefore, we have developed a novel flame retardant based on a bimetallic-doped phytate-melamine (BPM) structure with Zn²⁺ and Fe²⁺ ions incorporated into the polymer matrix using a straightforward solution-based synthetic method. The combustion performance of the composite was evaluated using a cone calorimeter test, which showed that the peak heat release, total heat release, and total smoke production were reduced by 50%, 31.7%, and 29.2%, respectively, compared to those of EP. Additionally, the fire growth index was noticeably reduced by 60% owing to the synergistic catalytic effect of the bimetallic ions, and the high nitrogen and phosphorus content of the additives. Overall, this study provides new insights into the application of bimetallic doping for flame retardant polymer composites.

PMID:39771438 | PMC:PMC11679077 | DOI:10.3390/polym16243586

Toxics. 2024 Nov 29;12(12):870. doi: 10.3390/toxics12120870.

ABSTRACT

Growing concerns about the health risks of melamine adulteration in food products highlight the urgent need for reliable detection methods. However, the long-term effects of chronic low-level melamine exposure remain inadequately explored. This study introduces THE ONE InstantCare platform, a portable immunoassay analyzer integrating a SpectroChip-based spectral processing unit (SPU) with lateral flow immunoassay (LFIA) for sensitive and accurate quantification of melamine in human urine. This platform provides a cost-effective, rapid, and user-friendly point-of-care (POC) solution for melamine detection. Analytical evaluations across eight melamine concentrations (0-100 parts per billion, ppb) achieved a limit of detection (LOD) of 1.91 ppb. Validation with 24 human urine samples demonstrated strong concordance with liquid chromatography-mass spectrometry (LC-MS), yielding an intraclass correlation coefficient (ICC) of 0.9220, a Pearson correlation coefficient of 0.9389, and 95% agreement in Bland-Altman analysis. High reproducibility was observed, with an intraday coefficient of variation (CV) of 6.53% and acceptable interday CV values, while interference studies confirmed reliability in the presence of common biological substances. By delivering results in approximately 10 min, THE ONE InstantCare platform significantly reduces analysis time compared to LC-MS, which typically requires several hours. This novel platform enhances food safety surveillance and advances human health risk assessments, particularly for evaluating melamine-linked kidney damage. Its versatility and robust performance make it a promising tool for environmental monitoring and clinical diagnostics, enabling the detection of diverse biomarkers with high sensitivity and reproducibility.

PMID:39771085 | PMC:PMC11679044 | DOI:10.3390/toxics12120870

Environ Int. 2025 Jan;195:109227. doi: 10.1016/j.envint.2024.109227. Epub 2024 Dec 24.

ABSTRACT

Melamine, its analogues, and aromatic amines (AAs) were commonly detected in a previous study of pregnant women in the Environmental influences on Child Health Outcomes (ECHO) Cohort. While these chemicals have identified toxicities, little is known about their influences on fetal development. We measured these chemicals in gestational urine samples in 3 ECHO cohort sites to assess associations with birth outcomes (n = 1,231). We estimated beta coefficients and 95% confidence intervals (CIs) using adjusted linear mixed models with continuous dilution-standardized concentrations (log₂ transformed and scaled by interquartile range, IQR) or binary indicators for detection. As secondary analyses, we repeated analyses using categorical outcomes. Forty-one of 45 analytes were detected in at least one sample, with > 95 % detection of melamine, cyanuric acid, ammelide, and aniline. Higher melamine concentration was associated with longer gestational age (β^ per IQR increase of log₂-transformed: 0.082 [95 % CI: -0.012, 0.177]; 2nd vs 1st tertile: 0.173 [-0.048, 0.394]; 3rd vs 1st tertile: 0.186 [-0.035, 0.407]). Similarly in secondary analyses using categorical outcomes, an IQR increase in log₂(melamine) was associated with 1.22 [0.99, 1.50] higher odds of post-term (>40 & ≤42 weeks) as compared to full-term (≥38 & ≤40 weeks). Several AAs were associated with birthweight and gestational length, with the direction of associations varying by AA. Some stronger associations were observed in females. Our findings suggest melamine and its analogs and AAs may influence gestational length and birthweight.

PMID:39740267 | PMC:PMC11826381 | DOI:10.1016/j.envint.2024.109227

Int J Biol Macromol. 2025 Mar;294:139248. doi: 10.1016/j.ijbiomac.2024.139248. Epub 2024 Dec 29.

ABSTRACT

Chitosan, a versatile biopolymer derived from chitin, is increasingly recognized in the milk industry for its multifunctional applications in drug delivery, smart packaging, and biosensor development. This review provides a comprehensive analysis of recent advances in chitosan production techniques. These include chemical, biological, and novel methods such as deep eutectic solvents (DES), microwave-assisted approaches, and laser-assisted processes. Surface modification strategies to enhance its functional properties are also discussed. The review highlights the development of various chitosan-based nanocarriers, including nanoparticles, nanofibers, nanogels, and nanocomposites. It emphasizes their stability when combined with milk bioactive ingredients like lipids, peptides, lactose, and minerals. The gastrointestinal fate and safety of chitosan nanoparticles are critically evaluated, showcasing their potential for safe consumption in dairy-related applications. In drug delivery systems, chitosan exhibits excellent compatibility with milk-derived carbohydrates, proteins, and minerals, enabling the development of innovative drug delivery platforms. Additionally, its incorporation into smart packaging materials enhances the shelf-life and quality of dairy products. Chitosan-based biosensors offer precise contaminant detection in the milk industry by enabling precise detection of contaminants such as Bisphenol A, melamine, bacteria, drugs, antibiotics, toxins, heavy metals, and allergens, thus ensuring food safety and quality. Emerging trends, including the integration of artificial intelligence, advanced gene editing, and multifunctional chitosan, are discussed, offering insights into future personalized delivery systems and merging food and drug technologies. The review concludes by highlighting gaps in current research and offering recommendations for future exploration. These suggestions aim to optimize chitosan's unique properties to address key challenges in the milk industry. This article serves as a valuable resource for researchers, industry professionals, and policymakers aiming to innovate within the dairy sector using chitosan-based technologies.

PMID:39740715 | DOI:10.1016/j.ijbiomac.2024.139248

Biosensors (Basel). 2024 Dec 3;14(12):591. doi: 10.3390/bios14120591.

ABSTRACT

Surface-enhanced Raman scattering (SERS) is a powerful optical sensing platform that amplifies the target signals by Raman scattering. Despite SERS enabling a meager detection limit, even at the single-molecule level, SERS also tends to equally enhance unwanted molecules due to the non-specific binding of noise molecules in clinical samples, which complicates its use in complex samples such as bodily fluids, environmental water, or food matrices. To address this, we developed a novel non-fouling biomimetic SERS sensor by self-assembling an anti-adhesive, anti-fouling, and size-selective Lubricin (LUB) coating on gold nanoparticle (AuNP) functionalized glass slide surfaces via a simple drop-casting method. Compared to a conventional AuNPs-SERS substrate, the biomimetic SERS meets the requirements of simple preparation and enables direct droplet detection without any sample pre-treatment. Atomic force microscopy was used to confirm the self-assembled Lubricin coating on the AuNP surface, acting as an anti-fouling and size-selective protection layer. A series of Raman spectra were collected using melamine as the target analyte, which was spiked into 150 mM NaCl solution or undiluted milk. It was demonstrated that the LUB coating effectively prevents the detrimental fouling generated by the proteins and fats in milk, ensuring the clear detection of melamine. Our sensor showed high selectivity and could detect melamine in milk at concentrations as low as 1 ppm. Given that the EU/US legal limit for melamine in food is 2.5 ppm, this sensor offers a promising, cost-effective solution for routine screening and has potential applications for detecting food adulteration in the food safety, environmental monitoring, aquaculture, and biomedical fields.

PMID:39727856 | PMC:PMC11674473 | DOI:10.3390/bios14120591

Environ Int. 2024 Dec;194:109188. doi: 10.1016/j.envint.2024.109188. Epub 2024 Dec 9.

ABSTRACT

Melamine has several domestic and industrial uses as a flame retardant or in the manufacture of melamine-formaldehyde resins. Based on available scientific literature data, the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) included this substance in the list of "chemicals that may present endocrine disruptor (ED) properties", and the substance was prioritized to assess whether it should be classified as an ED in European Union (EU) regulations for hazard identification. This review reports the assessment of melamine based on relevant studies from the registration dossier under REACH, and peer-reviewed literature. Among the various adverse effects, reproductive, neurodevelopmental, and thyroid effects were analyzed in particular, because they could be the consequence of an endocrine disruption. The different modes of action (endocrine or non-endocrine) potentially leading to these effects were scrutinized to understand whether the WHO definition for ED and the criteria for hazard identification were met. It was concluded that the reproductive effect on spermatogenesis was not a consequence of endocrine activity. A biologically plausible link between this effect and endocrine activity was not established, and other modes of action (oxidative stress or altered energy metabolism) could be involved. Similarly, thyroid and neurodevelopmental effects appeared at higher doses than those leading to renal toxicity. Our assessment confirms that melamine is a reprotoxic substance but does not support ED classification. This assessment illustrates the scientific and regulatory challenges in differentiating specific endocrine disruption from an indirect endocrine effect resulting from non-ED mediated systemic toxicity.

PMID:39671826 | DOI:10.1016/j.envint.2024.109188

Anal Methods. 2025 Jan 16;17(3):552-561. doi: 10.1039/d4ay01764a.

ABSTRACT

This work presents two novel devices with a microcontroller and two different light sensors, namely, Light Dependent Resistor (LDR) and Ambient Light Sensor (ALS), which can provide a quantitative output from the colorimetric variations of citrate capped borohydride reduced silver nanoparticles (AgNPs) and citrate capped gold nanoparticles (AuNPs) upon addition of melamine adulterated milk. The limit of detection (LOD) of the LDR setup with AgNPs and AuNPs was found to be 1.24 ppm and 1.68 ppm, respectively, and the corresponding recovery rates were 92.86% and 88.57%, respectively. The device fabricated with the ALS with AgNPs displayed a recovery rate of 97.14% with a LOD value of 0.64 ppm.

PMID:39663989 | DOI:10.1039/d4ay01764a

Ecotoxicol Environ Saf. 2025 Jan 1;289:117513. doi: 10.1016/j.ecoenv.2024.117513. Epub 2024 Dec 10.

ABSTRACT

Subchronic exposure to cyanuric acid (CA) and its structural analogue melamine induces long-term effects on brain and behavior in male rodents. To examine if this exposure induced negative effects on cognitive function in females, we examined the behavioral performance and further attempted to investigate synaptic and neuronal function. CA was intraperitoneal treated with 20 or 40 mg/kg/day to adolescent female rats for 4 consecutive weeks. Multiple behavioral tests were employed to assess spatial cognition, learning strategy, locomotion and motivation. Hippocampal synaptic function at Schaffer collaterals-CA1 synapses and excitatory postsynaptic currents (EPSCs) in CA1 pyramidal neurons was evaluated. Meanwhile, the glutamate transport inhibitor DL-threo-β-benzyloxyaspartate (DL-TBOA) was infused into hippocampal CA1 region to certify the underlying mechanism. We found that subchronic CA exposure impairs reversal learning ability with dose-dependent effects but did not affect spatial learning and memory, or learning strategy. The expression and phosphorylation of N-methyl-D-aspartate receptor (NMDAR) GluN2B subunits were simultaneously reduced in the hippocampus and the GluN2B-mediated synaptic function, including long-term depression (LTD) and paired-pulse facilitation (PPF), was suppressed. CA could also diminish postsynaptic density protein-95 (PSD-95) expression but did change the levels of α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptor (AMPAR) GluA1 or NMDAR GluN2A subunit, or hippocampal spine density. Meanwhile, CA depressed frequency and amplitude of GluN2B-mediated EPSCs, indicating the presynaptic and postsynaptic actions of CA on neuronal activity. Furthermore, the DL-TBOA infusions could effectively mitigate the diminished GluN2B-LTD and GluN2B-EPSCs and the impairments in behavioral flexibility. Our findings provide the first evidence that CA can exert neurotoxic effects on females and certify that one of the potential mechanisms for neuronal and synaptic dysfunction is the GluN2B-mediated signaling pathway.

PMID:39662458 | DOI:10.1016/j.ecoenv.2024.117513

RSC Adv. 2024 Dec 9;14(52):38706-38720. doi: 10.1039/d4ra07688e. eCollection 2024 Dec 3.

ABSTRACT

A root-like waterborne hyperbranched polymer, synthesized from diethylenetriamine (DETA) and methyl acrylate (MA) monomers, was inspired by the effect of solidifying soil with tree roots. This polymer was then blended with aqueous isocyanate SK615, known as MD-HBP-NH₂, to serve as a surface modifier for blockboards. The blockboards were treated with a modifier to enhance the interfacial adhesion with melamine-formaldehyde (MF) resin-impregnated decorative paper, thereby preventing surface cracks. The polycondensation reaction temperatures of the modifiers were compared. These results indicated that a hyperbranched root-structured polymer emulsion was formed through Michael addition reactions. Following this modification, the blockboards demonstrated enhanced planeness and dimensional stability. Furthermore, the isocyanate groups reacted with the exposed hydroxyl groups, and the amino groups reacted with the aldehyde groups in the MF resin, thereby enhancing the interfacial bonding strength between the wood and the impregnated decorative paper. At a polycondensation temperature of 155 °C, optimal overall performance was attained, with the ability to penetrate the wood surface to a depth of 1.28 mm, and exhibited superior surface crack resistance. Moreover, this waterborne hyperbranched polymer modifier is eco-friendly, green, and non-toxic, with lower levels of volatile organic compounds. This presents a promising avenue for the development of eco-friendly modifiers to prevent surface cracking in wood-based panels with impregnated decorative paper.

PMID:39654920 | PMC:PMC11626439 | DOI:10.1039/d4ra07688e

Toxicol Appl Pharmacol. 2025 Feb;495:117190. doi: 10.1016/j.taap.2024.117190. Epub 2024 Dec 6.

ABSTRACT

Kidney stones resulting from ingestion of melamine-tainted food products were originally detected in dogs and cats in 2004 and 2007. Nephroliths were removed at necropsy from dogs that had died from acute kidney injury in Asia in 2004. Samples of these were submitted to our laboratories for analysis. The presence of a mixed s-triazine matrix comprising melamine, cyanuric acid, and ammelide, but no detectable ammeline was found in the canine stone samples we analyzed. The unusual and unique green coloration of these stones was attributed to the presence of biliverdin. The techniques developed in the canine study were applied to the analysis of human kidney stones. In 2008, high levels of melamine were detected in some infant formula and other liquid and powdered milk products originating from China. Human kidney stones, resulting from this type of contamination, were obtained from children, and analyzed using mass spectral techniques. The results indicated the presence of melamine, ammeline, uric acid, but no ammelide. No green color was observed, thereby eliminating biliverdin. Careful monitoring of food additives is warranted to prevent future problems in both animals and humans.

PMID:39647512 | DOI:10.1016/j.taap.2024.117190

Chemosphere. 2025 Feb;370:143918. doi: 10.1016/j.chemosphere.2024.143918. Epub 2024 Dec 10.

ABSTRACT

Melamine has a high production volume today and is spread ubiquitously in the anthropogenic technosphere. It is released steadily to the water cycle by many sources. Even though melamine has low direct toxicity, chronic exposure can cause nephrolithiasis and disrupt the endocrine system. Most data on melamine is based on case studies with, when compared, partially contradictive implications. As melamine is a compound of many sources (SMS), very persistent, mobile (vPvM), and toxic (PMT) it has the potential to break through natural barriers posing a potential risk to drinking water resources. This study combines existing data with own measurements gathered through various individual monitoring campaigns with the aim to gain new insights into its environmental behaviour and hotspots. Samples from surface water bodies, groundwater, wastewater (treated, untreated), and soil samples were analysed regarding their melamine concentration via liquid chromatography coupled with tandem mass spectrometry (LC-MSMS). Besides three drinking water samples, melamine could be found in all water samples (n = 632) of this study, with a maximum concentration of 1289 ng/L in drinking water and 1120 ng/L in groundwater. While a constant baseline melamine concentration with an event-based release could be observed in most surface water bodies, higher concentrations towards Western Europe (urbanisation and chemical industry) was observed for wastewater. A similar pattern was found in the spatial distribution of melamine in agricultural soils towards an urban/suburban area. As, in general, melamine concentrations were higher towards urbans centers melamine can also be classified as an indicator of anthropogenic activity and urbanisation, but also spotlights on these areas as hotspots for potentially many compounds of the human technosphere. We call policy to shift from the existing one-size-fits-all solution to more flexible and risk-based approaches to prepare for future challenges.

PMID:39647792 | DOI:10.1016/j.chemosphere.2024.143918

Chemosphere. 2025 Feb;370:143918. doi: 10.1016/j.chemosphere.2024.143918. Epub 2024 Dec 10.

ABSTRACT

Melamine has a high production volume today and is spread ubiquitously in the anthropogenic technosphere. It is released steadily to the water cycle by many sources. Even though melamine has low direct toxicity, chronic exposure can cause nephrolithiasis and disrupt the endocrine system. Most data on melamine is based on case studies with, when compared, partially contradictive implications. As melamine is a compound of many sources (SMS), very persistent, mobile (vPvM), and toxic (PMT) it has the potential to break through natural barriers posing a potential risk to drinking water resources. This study combines existing data with own measurements gathered through various individual monitoring campaigns with the aim to gain new insights into its environmental behaviour and hotspots. Samples from surface water bodies, groundwater, wastewater (treated, untreated), and soil samples were analysed regarding their melamine concentration via liquid chromatography coupled with tandem mass spectrometry (LC-MSMS). Besides three drinking water samples, melamine could be found in all water samples (n = 632) of this study, with a maximum concentration of 1289 ng/L in drinking water and 1120 ng/L in groundwater. While a constant baseline melamine concentration with an event-based release could be observed in most surface water bodies, higher concentrations towards Western Europe (urbanisation and chemical industry) was observed for wastewater. A similar pattern was found in the spatial distribution of melamine in agricultural soils towards an urban/suburban area. As, in general, melamine concentrations were higher towards urbans centers melamine can also be classified as an indicator of anthropogenic activity and urbanisation, but also spotlights on these areas as hotspots for potentially many compounds of the human technosphere. We call policy to shift from the existing one-size-fits-all solution to more flexible and risk-based approaches to prepare for future challenges.

PMID:39647792 | DOI:10.1016/j.chemosphere.2024.143918

Chemistry. 2025 Feb 6;31(8):e202403770. doi: 10.1002/chem.202403770. Epub 2024 Dec 11.

ABSTRACT

Αfter the impressive evolution of graphene and its derivatives, a large number of two dimensional (2D) materials with important optical and electrical properties have been successfully fabricated. Liquid phase exfoliation (LPE) of layered and non-layered materials has become a widely applied method for the preparation of 2D nanostructures with an extensive variety of applications. However, in most cases organic solvents are used as liquid phase which are often toxic and environmentally unfriendly and lead to low yields. In this work, we present water as a suitable liquid phase and dispersion medium for the exfoliation of layered and non-layered monoelemental solids from IV_A, V_A and VI_A groups of the periodic table, such as silicon, tin, bismuth and tellurium. The 2D nanostructures, silicene, stanene, bismuthene and tellurene are therefore prepared by a completely sustainable and environmentally friendly method. The prepared Xenes, as they are called, are fully characterized by microscopic and spectroscopic techniques.

PMID:39625366 | PMC:PMC11803363 | DOI:10.1002/chem.202403770

Biosens Bioelectron. 2025 Feb 15;270:116991. doi: 10.1016/j.bios.2024.116991. Epub 2024 Nov 26.

ABSTRACT

Nanozymes, a category of nanomaterials with exceptional enzyme-like activity, exhibit the significant promise to overcome the inherent limitations of natural enzymes. Inspired by the active site structure of natural laccase, a biomimetic MA-Cu nanozyme with three-dimensional network structure was constructed in water system through one-step complexation based on the specific coordination between nitrogen-rich triazine heterocyclic melamine and Cu²⁺, in a facile, green and economical manner. Compared to natural laccase, MA-Cu possesses superior multi-enzyme mimicking activity, stability and cost-effectiveness. Through comprehensive characterizations, activity tests and theoretical calculations, the catalytic mechanism and the ligand-tunability of enzyme-like activity have been thoroughly investigated. Based on its multi-enzyme-like activities, a multifunctional monitoring platform for sulfide in food, epinephrine in preparations and glutathione in cells was successfully constructed, respectively. Notably, a green degradation and discrimination platform based on MA-Cu for various pollutants was developed, exhibiting distinguished substrate universality and detoxication capacity. As a stable, easily scalable and commercially applicable nanozyme, MA-Cu is expected to become a compelling candidate for replacing natural enzyme, showing excellent prospects in environmental remediation and biosensing.

PMID:39603212 | DOI:10.1016/j.bios.2024.116991

Environ Sci Technol. 2024 Apr 16;58(15):6814-6824. doi: 10.1021/acs.est.4c00577. Epub 2024 Apr 6.

ABSTRACT

Identifying persistent, mobile, and toxic (PMT) substances from synthetic chemicals is critical for chemical management and ecological risk assessment. Inspired by the triazine analogues (e.g., atrazine and melamine) in the original European Union's list of PMT substances, the occurrence and compositions of alkylamine triazines (AATs) in the estuarine sediments of main rivers along the eastern coast of China were comprehensively explored by an integrated strategy of target, suspect, and nontarget screening analysis. A total of 44 AATs were identified, of which 23 were confirmed by comparison with authentic standards. Among the remaining tentatively identified analogues, 18 were emerging pollutants not previously reported in the environment. Tri- and di-AATs were the dominant analogues, and varied geographic distributions of AATs were apparent in the investigated regions. Toxic unit calculations indicated that there were acute and chronic risks to algae from AATs on a large geographical scale, with the antifouling biocide cybutryne as a key driver. The assessment of physicochemical properties further revealed that more than half of the AATs could be categorized as potential PMT and very persistent and very mobile substances at the screening level. These results highlight that AATs are a class of PMT substances posing high ecological impacts on the aquatic environment and therefore require more attention.

PMID:38581381 | DOI:10.1021/acs.est.4c00577

Environ Sci Technol. 2023 Oct 3;57(39):14694-14706. doi: 10.1021/acs.est.3c02945. Epub 2023 Sep 21.

ABSTRACT

Persistent, mobile, and toxic (PMT) substances are affecting the safety of drinking water and are threatening the environment and human health. Many PMT substances are used in industrial processing or consumer products, but their sources and emissions mostly remain unclear. This study presents a long-term source distribution and emission estimation of melamine, a high-production-volume PMT substance of emerging global concern. The results indicate that in China, approximately 1858.7 kilotonnes (kt) of melamine were released into the water (∼58.9%), air (∼27.0%), and soil systems (∼14.1%) between 1995 and 2020, mainly from its production and use in the decorative panels, textiles, and paper industries. The textile and paper industries have the highest emission-to-consumption ratios, with more than 90% emissions per unit consumption. Sewage treatment plants are the largest source of melamine in the environment for the time being, but in-use products and their wastes will serve as significant melamine sources in the future. The study prompts priority action to control the risk of PMT substances internationally.

PMID:37734035 | PMC:PMC11017250 | DOI:10.1021/acs.est.3c02945

Huan Jing Ke Xue. 2023 Jun 8;44(6):3017-3023. doi: 10.13227/j.hjkx.202207182.

ABSTRACT

Persistent, mobile, and toxic or very persistent and very mobile (PMT/vPvM) chemicals have been widely detected in surface water, groundwater, and drinking water around the world and are important emerging contaminants that may significantly affect human health and the environment in the future. According to the identification criteria proposed by the European Union, there are thousands of PMT/vPvM substances in existing chemicals, covering a wide range of applications, including dozens of high-yield industrial chemicals such as melamine. PMT/vPvM chemicals can be discharged into the environment through farmland runoff, industrial wastewater, and domestic sewage, and sewage treatment plants are currently considered to be their main discharge route. It is difficult to effectively remove PMT/vPvM chemicals through the current conventional water treatment technology; they can exist in the water circulation system of the urban human settlement environment for a long time, endangering the safety of drinking water and the ecosystem. The European Union has taken the lead in introducing PMT/vPvM chemicals specifically into the priority areas of the current chemical risk management system. At present, there are still many potential PMT/vPvM chemicals in the environment, and their monitoring methods need to be further improved. It will take time for the identification of substances, the scope of categories, and the establishment of lists. Studies on the environmental fate and exposure of PMT/vPvM in various regions of the world are still very limited, and research on the potential, long-term ecotoxicity, and human health hazard effects remains scarce. At the same time, the research and development of substitute or alternative technologies, as well as environmental engineering treatment technologies such as sewage treatment and contaminated site remediation, will become an urgent need for future PMT/vPvM risk scientific research and management decisions.

PMID:37309920 | DOI:10.13227/j.hjkx.202207182

Sci Total Environ. 2023 Sep 20;892:164264. doi: 10.1016/j.scitotenv.2023.164264. Epub 2023 May 19.

ABSTRACT

Green infrastructure drainage systems are innovative treatment units that capture and treat stormwater. Unfortunately, highly polar contaminants remain challenging to remove in conventional biofilters. To overcome treatment limitations, we assessed the transport and removal of stormwater vehicle-related organic contaminants with persistent, mobile, and toxic (in short: PMTs) properties, such as 1H-benzotriazole, NN'-diphenylguanidine, and hexamethoxymethylmelamine (PMT precursor), using batch experiments and continuous-flow sand columns amended with pyrogenic carbonaceous materials, like granulated activated carbon (GAC) or wheat-straw derived biochar. Our results indicated that all investigated contaminants were subjected to nonequilibrium interactions in sand-only and geomedia-amended columns, with kinetic effects upon transport. Experimental breakthrough curves could be well described by a one-site kinetic transport model assuming saturation of sorption sites, which we inferred could occur due to dissolved organic matter fouling. Furthermore, from both batch and column experiments, we found that GAC could remove contaminants significantly better than biochar with higher sorption capacity and faster sorption kinetics. Hexamethoxymethylmelamine, with the lowest organic carbon-water partition coefficient (K_OC) and largest molecular volume among target chemicals, exhibited the lowest affinity in both carbonaceous adsorbents based on estimated sorption parameters. Results suggest that sorption of investigated PMTs was likely driven by steric and hydrophobic effects, and coulombic and other weak intermolecular forces (e.g., London-van der Waals, H-bonding). Results from extrapolating our data to a 1-m depth geomedia-amended sand filter suggested that GAC and biochar could enhance the removal of organic contaminants in biofilters and last for more than one decade. Overall, our work is the first to study treatment alternatives for NN'-diphenylguanidine and hexamethoxymethylmelamine, and contributes to better PMT contaminant removal strategies in environmental applications.

PMID:37209730 | DOI:10.1016/j.scitotenv.2023.164264

Environ Sci Technol. 2022 Aug 2;56(15):10857-10867. doi: 10.1021/acs.est.2c03659. Epub 2022 Jul 22.

ABSTRACT

Persistent, mobile, and toxic (PMT) and very persistent and very mobile (vPvM) substances have been recognized as a threat to both the aquatic environment and to drinking water resources. These substances are currently prioritized for regulatory action by the European Commission, whereby a proposal for the inclusion of hazard classes for PMT and vPvM substances has been put forward. Comprehensive monitoring data for many PMT/vPvM substances in drinking water sources are scarce. Herein, we analyze 34 PMT/vPvM substances in 46 surface water, groundwater, bank filtrate, and raw water samples taken throughout Germany. Results of the sampling campaign demonstrated that known PMT/vPvM substances such as 1H-benzotriazole, melamine, cyanuric acid, and 1,4-dioxane are responsible for substantial contamination in the sources of German drinking water. In addition, the results revealed the widespread presence of the emerging substances 2-acrylamido-2-methylpropanesulfonic acid (AMPS) and diphenylguanidine (DPG). A correlation analysis showed a pronounced co-occurrence of PMT/vPvM substances associated predominantly with consumer or professional uses and also demonstrated an inhomogeneous co-occurrence for substances associated mainly with industrial use. These data were used to test the hypothesis that most PMT/vPvM substances pass bank filtration without significant concentration reduction, which is one of the main reasons for introducing PMT/vPvM as a hazard class within Europe.

PMID:35868007 | DOI:10.1021/acs.est.2c03659