Formaldehyde Exposure of Aquaculture Workers in Korea.

OBJECTIVES: Korea's aquaculture sector primarily cultivates aquatic life, with fish seed production as a focus. Formalin, a parasiticide, consists of 37% formaldehyde mixed with yellow No. 4 dye. Formaldehyde vaporization poses cancer risks, classified as a carcinogen. Korea regulates formaldehyde as a hazardous substance, requiring workplace environment measurements. Few aquaculture farms have conducted these checks in recent years. In this study, we investigated actual formaldehyde exposure levels among Korean aquaculture workers, highlighting a critical safety concern. METHODS: A field survey was conducted to measure formaldehyde exposure at 10 aquaculture farms in areas where Korean aquaculture is concentrated. Short-term and long-term personal samples, local samples, and direct-reading measurements were conducted. Formaldehyde exposure levels were detected in short-term personal samples from six farms and in long-term personal samples from two farms, and formaldehyde was detected in all local samples. In direct-reading measurements, a high concentration of formaldehyde was sustained for short periods. RESULTS: Long-term (8-hour) personal samples were mostly non-detectable, except for farms A and D, which had levels of 0.0009 ppm and 0.0017 ppm, respectively. Short-term (15-minute) samples were non-detectable in four farms, with an average of 0.0158 (±0.0130) ppm in the remaining six farms. Local samples from all farms had an average of 0.0384 (±0.0957) ppm of formaldehyde. For farms A and D, where long-term sampling detected formaldehyde, real-time measurements showed a sustained high concentration in farm A for about 48 minutes before decreasing. Farm D had no detectable formaldehyde throughout the monitoring period. CONCLUSION: According to the formaldehyde exposure level assessment, short term exposure to formaldehyde during and immediately after application of formalin nearly exceeded the ACGIH TLV STEL in one farm. However, concentration of long term samples appeared at 10% of ACGIH TLV TWA. Additional study is recommended to determine whether exposure to formaldehyde poses a health risk for aquaculture workers during application of formalin.

Photocatalytic oxidation of formaldehyde under visible light using BiVO4-TiO2 synthesized via ultrasonic blending.

Formaldehyde (HCHO) is one of the primary indoor air pollutants, and efficiently eliminating it, especially at low concentrations, remains challenging. In this study, BiVO4-TiO2 catalyst was developed using ultrasonic blending technology for the photocatalytic oxidation of low-level indoor HCHO. The crystal structure, surface morphology, element distribution, and active oxidation species of the catalyst were examined using XRD, SEM, TEM, UV-Vis, EDS, and ESR techniques. Our results demonstrated that the BiVO4-TiO2 catalyst, prepared by ultrasonic blending, exhibited good oxidation performance and stability. The HCHO concentration reduced from 1.050 to 0.030 mg/m3 within 48 h, achieving a removal rate of 97.1%. The synergy between BiVO4 and TiO2 enhanced the efficiency of separating photogenerated carriers and minimized the likelihood of recombination between photogenerated electrons and holes. Additionally, this synergy significantly enhanced the presence of hydroxyl radicals (·OH) on the catalyst, resulting in an oxidation performance superior to that of either BiVO4 or TiO2. Our research offers valuable insights for the development of new photocatalysts to address HCHO pollution.

Preparation of carboxymethyl chitosan/double-formaldehyde cellulose based hydrogel loaded with ginger essential oil nanoemulsion for meat preservation.

An antibacterial nano-hydrogel (ginger essential oil nanoemulsion hydrogel, GEONH) based on Schiff base reaction was prepared using double-formaldehyde micro fibrillated cellulose (DAMFC) and carboxymethyl chitosan (CMCS) loaded with ginger essential oil nanoemulsion (GEON). It was found that when the mass ratio of DAMFC/CMCS/GEON was 1/9/270, the gel time, the water absorbency, gel strength, and morphology were the best. The results of X-ray diffraction and FT-IR confirmed that the aldehyde group on the DAMFC molecular chain formed a stable chemical crosslinking with the amino group on the CMCS molecular chain, resulting in a change in the crystal structure. GEONH showed excellent bactericidal activity against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. Simultaneously, the prepared GEONH decreased the total viable count, Malondialdehyde, and total sulfhydryl content and improved the taste in the storage of boiled salted duck. Therefore, GEONH film is a promising fresh-keeping packaging for storing meat products. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01437-4.

Amine-Functionalized Meso-Macroporous Polymers for Efficient CO2 Capture from Ambient Air.

Over the past decade, direct air capture (DAC) of carbon dioxide (CO2) using solid nanoadsorbents has garnered attention as a negative emission technology with high energy efficiency. Although operational, the large-scale deployment of DAC technologies has been significantly delayed due to the low performance and high cost of solid DAC nanoadsorbents. Herein, we present a novel family of meso-macroporous melamine formaldehyde (MF) materials with a facile preparation methodology, low capital cost, and unique physicochemical characteristics for DAC. The fabricated MF materials exhibit an extra-large pore volume of 5.19 cm3/g with a 24.6 nm average pore diameter. We show that the synthesized MF materials can be used as substrates and impregnated with different amounts of tetraethylenepentamine (TEPA) to act as chemical nanoadsorbents for DAC. Owing to the ultrahigh pore volume of MF, a substantial amount of 71 wt % TEPA (i.e., MF-TEPA71%) can be loaded, resulting in 2.65 mmol/g of CO2 uptake under DAC conditions. In addition, the superior physicochemical properties of MF lead to a high CO2 loading of 2.07 mmol/g with low TEPA loading in MF-TEPA33%. The prepared MF-TEPA nanoadsorbents can be successfully employed in different shapes (i.e., droplets, pellets, and coatings) and maintain their superiority across different temperatures and CO2 concentrations. This study provides a promising approach for developing meso-macroporous substrates through a straightforward and scalable synthesis method, representing a new avenue for the next generation of DAC nanoadsorbents with superior performance for practical applications.

The effects of metal-oxide content in MnO2-activated carbon composites on reactive adsorption and catalytic oxidation of formaldehyde and toluene in air.

The deterioration in air quality caused by volatile organic compounds (VOCs) has become an important environmental issue. Here, activated carbon (AC) composites with manganese oxide (MnO2: 1 % to 50 %) are synthesized as MAC for the removal of formaldehyde (FA) and toluene in air through a combination of reactive adsorption and catalytic oxidation (RACO) at room temperature (RT). The best-performing composite (MAC-20: 20 % of MnO2) exhibits a 10 % breakthrough volume (BTV10%) of FA and toluene at 41.2 and 377 L g-1, respectively while realizing complete oxidation of FA and toluene into carbon dioxide (CO2) at 100 °C and 275 °C, respectively. The reaction kinetic rates (r) for 10 % removal efficiency of FA and toluene (XFA or T) at RT are estimated as 9.82E-02 and 3.20E-02 mmol g-1 h-1, respectively. The high performance of MAC-20 can be attributed to its enriched adsorption capacity of oxygen vacancy (OV) and the presence of adsorbed oxygen (OA), as shown by an Mn3+/Mn4+ ratio of 0.729 and an OA/lattice­oxygen (OL) ratio of 1.50. The results of this study highlight the interactive roles of oxygen abundance and temperature in the generation of distinctive oxidation patterns for FA in reference to toluene. This study is expected to offer practical guidance for the implementation of RACO against diverse VOCs for efficient management of air quality.

The practical utility of ternary nickel-cobalt-manganese oxide-supported platinum catalysts for room-temperature oxidative removal of formaldehyde from the air.

Formaldehyde (FA), a carcinogenic oxygenated volatile organic compound, is present ubiquitously in indoor air. As such, it is generally regarded as a critical target for air quality management. The oxidative removal of FA under dark and room-temperature (RT) conditions is of practical significance. A series of ternary nickel-cobalt-manganese oxide-supported platinum catalysts (Pt/NiCoMnO4) have been synthesized for FA oxidative removal at RT in the dark. Their RT conversion values for 50 ppm FA (XFA) at 5,964 h-1 gas hourly space velocity (GHSV) decrease in the following order: 1 wt% Pt/NiCoMnO4 (100 %) > 0.5 wt% Pt/NiCoMnO4 (25 %) > 0.05 wt% Pt/NiCoMnO4 (14 %) > NiCoMnO4 (6 %). The catalytic performance of 1 wt% Pt/NiCoMnO4 has been examined further under the control of various process variables (e.g., catalyst mass, flow rate, relative humidity, FA concentration, time on stream, and molecular oxygen content). The catalytic oxidation of FA at low temperatures (e.g., RT and 60 °C) is accounted for by Langmuir-Hinshelwood mechanism (single-site competitive-adsorption), while Mars van Krevelen kinetics is prevalent at higher temperatures. In situ diffuse-reflectance infrared Fourier-transform spectroscopy reveals that FA oxidation proceeds through a series of reaction intermediates such as DOM, HCOO-, and CO32-. Based on the density functional theory simulations, the unique electronic structures of the nearest surface atoms (platinum and nickel) are suggested to be responsible for the superior catalytic activity of Pt/NiCoMnO4.

The impact of formaldehyde exposure on lung inflammatory disorders: Insights into asthma, bronchitis, and pulmonary fibrosis.

Lung inflammatory disorders are a major global health burden, impacting millions of people and raising rates of morbidity and death across many demographic groups. An industrial chemical and common environmental contaminant, formaldehyde (FA) presents serious health concerns to the respiratory system, including the onset and aggravation of lung inflammatory disorders. Epidemiological studies have shown significant associations between FA exposure levels and the incidence and severity of several respiratory diseases. FA causes inflammation in the respiratory tract via immunological activation, oxidative stress, and airway remodelling, aggravating pre-existing pulmonary inflammation and compromising lung function. Additionally, FA functions as a respiratory sensitizer, causing allergic responses and hypersensitivity pneumonitis in sensitive people. Understanding the complicated processes behind formaldehyde-induced lung inflammation is critical for directing targeted strategies aimed at minimizing environmental exposures and alleviating the burden of formaldehyde-related lung illnesses on global respiratory health. This abstract explores the intricate relationship between FA exposure and lung inflammatory diseases, including asthma, bronchitis, allergic inflammation, lung injury and pulmonary fibrosis.

Characteristic phenotypes of ADH5/ALDH2 deficiency during childhood.

ADH5/ALDH2 deficiency is a rare inherited syndrome characterized by short stature, microcephaly, delayed mental development, and hematopoietic dysfunction and has recently been proposed as a disease paradigm. Acute and severe presentations include aplastic anemia, myelodysplastic syndrome, or leukemia, requiring bone marrow transplantation during childhood. Conversely, non-hematological manifestations may exhibit a prolonged and nonspecific clinical trajectory, with growth failure and developmental delay, most of which are often overlooked, particularly in patients with milder symptoms. Here, we describe the clinical course of a girl with a wide spectrum of clinical presentations, including nonspecific hematopoietic disorders, growth retardation, mild developmental delay, amblyopia, hemophagocytic lymphohistiocytosis, and verruca vulgaris, culminating in a genetic diagnosis of AMeD syndrome at 12 years of age. We also summarized the clinical manifestations of previously reported cases of AMeD syndrome. Cumulatively, 13 females and 5 males have been documented, with a cardinal triad of symptoms, aplastic anemia, short stature, and intellectual disability. Additional characteristic observations included pigmentary deposition in approximately half of the cases and skeletal difficulties in one-quarter. We propose that early diagnosis of patients who exhibit relatively mild phenotypes of skin or skeletal lesions is important for managing and improving the quality of life of patients with AMeD syndrome.

The Removal of Formaldehyde from Urea Formaldehyde Adhesive by Sodium Borohydride Treatment and Its Application in Plywood.

The global production of plywood is constantly increasing as its application in the furniture and interior decoration industry becomes more widespread. An urgent issue is how to decrease the formaldehyde released from plywood, considering its carcinogenic effect on humans and harm to the environment. Reducing the free formaldehyde content of the urea formaldehyde (UF) adhesives used in the preparation process is considered an effective method. Therefore, it is necessary to identify a new type of formaldehyde scavengers. Here, the strongly reducing substance sodium borohydride was used to reduce and degrade the free formaldehyde in UF adhesives, and its effects on the properties of the UF adhesive and plywood were studied. When 0.7% sodium borohydride was added to the UF adhesive with a molar ratio of formaldehyde to urea of 1.4:1, the free formaldehyde content of the UF resin decreased to 0.21%, which is 53% lower than that of the untreated control. Moreover, the formaldehyde released from the plywood was reduced to 0.81 mg/L, ~45% lower than that from the group. The bonding strength of the treated samples could reach ~1.1 MPa, which was only reduced by ~4% compared to that of the control. This study of removing formaldehyde from UF adhesive by reduction could provide a new approach for suppressing formaldehyde release from the final products.

Synthesis of BiOX-Red Mud/Granulated Blast Furnace Slag Geopolymer Microspheres for Photocatalytic Degradation of Formaldehyde.

Release of formaldehyde gas indoors is a serious threat to human health. The traditional adsorption method is not stable enough for formaldehyde removal. Photocatalytic degradation of formaldehyde is effective and rapid, but photocatalysts are generally expensive and not easy to recycle. In this paper, geopolymer microspheres were applied as matrix materials for photocatalysts loading to degrade formaldehyde. Geopolymer microspheres were prepared from red mud and granulated blast furnace slag as raw materials by alkali activation. When the red mud doping was 50%, the concentration of NaOH solution was 6 mol/L, and the additive amount was 30 mL, the prepared geopolymer microspheres possessed good morphological characteristics and a large specific surface area of 38.80 m2/g. With the loading of BiOX (X = Cl, Br, I) photocatalysts on the surface of geopolymer microspheres, 85.71% of formaldehyde gas were adsorbed within 60 min. The formaldehyde degradation rate of the geopolymer microspheres loaded with BiOI reached 87.46% within 180 min, which was 23.07% higher than that of the microspheres loaded with BiOBr, and 50.50% higher than that of the microspheres loaded with BiOCl. While ensuring the efficient degradation of formaldehyde, the BiOX (X = Cl, Br, I)-loaded geopolymer microspheres are easy to recycle and can save space. This work not only promotes the resource utilization of red mud and granulated blast furnace slag, but also provides a new idea on the formation of catalysts in the process of photocatalytic degradation of formaldehyde.

Cu-doped Fe3O4 nanoparticles for efficient detoxification of epsilon toxin: Toward substituting magnetically recyclable detoxifying agent for formaldehyde.

This research presents the synthesis and characterization of Cu-doped Fe3O4 (Cu-Fe3O4) nanoparticles as a magnetically recoverable and reusable detoxifying agent for the efficient and long-lasting neutralization of bacterial toxins. The nanoparticles were synthesized using the combustion synthesis method and characterized through SEM, XRD, BET, TGA, and VSM techniques. The detoxification potential of Cu-Fe3O4 was compared with traditional formaldehyde (FA) in detoxifying epsilon toxin (ETx) from Clostridium perfringens Type D, the causative agent of enterotoxemia in ruminants. In vivo residual toxicity tests revealed that Cu-Fe3O4 could detoxify ETx at a concentration of 2.0 mg mL-1 within 4 days at room temperature (RT) and 2 days at 37 °C, outperforming FA (12 and 6 days at RT and 37 °C, respectively). Characterization studies using dynamic light scattering (DLS) and circular dichroism (CD) highlighted lower conformational changes in Cu-Fe3O4-detoxified ETx compared to FA-detoxified ETx. Moreover, Cu-Fe3O4-detoxified ETx exhibited exceptional storage stability at 4 °C and RT for 6 months, maintaining an irreversible structure with no residual toxicity. The particles demonstrated remarkable reusability, with the ability to undergo five continuous detoxification batches. This study provides valuable insights into the development of an efficient and safe detoxifying agent, enabling the production of toxoids with a native-like structure. The magnetically recoverable and reusable nature of Cu-Fe3O4 nanoparticles offers practical advantages for easy recovery and reuse in detoxification reactions.

Surfactant-assisted molecular-level tunning of phenol-formaldehyde-based hard carbon microspheres for high-performance sodium-ion batteries.

The phenol-formaldehyde (PF) resin is an economical precursor for spherical hard carbon (HC) anodes for sodium-ion batteries (SIBs). However, achieving precise molecular-level control of PF-based HC microspheres, particularly for optimizing ion transport microstructure, is challenging. Here, a sodium linoleate (SL)-assisted strategy is proposed to enable molecular-level engineering of PF-based HC microspheres. PF microspheres are synthesized through the polymerization of 3-aminophenol and formaldehyde, initially forming oxazine rings and then undergoing ring-opening polymerization to create a macromolecular network. SL functions as both a surfactant to control microsphere size and a catalyst to enhance ring-opening polymerization and increase polymerization of PF resin. These modifications lead to reduced microsphere diameter, increased interlayer spacing, enhanced graphitization, and significantly improved electron and ion transfer. The synthesized HC microspheres exhibit a remarkable reversible capacity of 337 mAh/g, maintaining 96.9 mAh/g even at a high current density of 5.0 A/g. Furthermore, the full cell demonstrates a high capacity of 150 mAh/g, an energy density of 125.3 Wh kg-1, an impressive initial coulombic efficiency (ICE) of 930.3% at 1 A/g, and remarkable long-term stability over 3000 cycles. This study highlights the potential of surfactant-assisted molecular-level engineering in customizing HC microspheres for advanced SIBs.

Molded Plywood with Proportions of Beech Bark in Adhesive Mixtures: Production on an Industrial Scale.

Molded plywood is used for furniture components such as seats, backrests, or integral seat shells, and it must be durable and harmless to health. Molded plywood is made with urea-formaldehyde (UF) adhesives; therefore, the issue of the fillers used in them is important. The potential of using ground beech (Fagus sylvatica L.) bark as an eco-friendly additive in UF adhesives for molded plywood manufacturing was investigated in this work. Wheat flour was used as a reference filler. The beech bark (BB) level as a filler was 10%, a value verified under laboratory conditions. Nine-layer flat and molded plywood were produced under industrial conditions from beech veneers bonded with a UF adhesive mixture. The mechanical (bending strength and bonding quality) and physical (swelling and absorbency values after 2 and 24 h) properties of the industrially fabricated molded plywood were evaluated and compared with the European standard requirements (EN 310 and EN 314-2). The mechanical properties of the molded plywood with the addition of BB in the adhesive mixture were acceptable and met these standards' requirements. The positive effect of BB in the UF adhesive mixture on a reduction in formaldehyde emissions from the molded plywood was also confirmed. BB, considered to be wood-processing industry waste or a by-product, has significant potential to be used as a filler in UF resins for molded plywood production, providing an environmentally friendly, inexpensive solution for the industrial valorization of bark as a bio-based formaldehyde scavenger.

Construction of a Visible-Light-Response Photocatalysis-Self-Fenton Degradation System of Coupling Industrial Waste Red Mud to Resorcinol-Formaldehyde Resin.

Heterogeneous photocatalysis-self-Fenton technology is a sustainable strategy for treating organic pollutants in actual water bodies with high-fluent degradation and high mineralization capacity, overcoming the limitations of the safety risks caused by adding external iron sources and hazardous chemicals in the homogeneous Fenton reaction and injecting high-intensity energy fields in photo-Fenton reaction. Herein, a photo-self-Fenton system based on resorcinol-formaldehyde (RF) resin and red mud (RM) was established to generate hydrogen peroxide (H2O2) in situ and transform into hydroxy radical (•OH) for efficient degradation of tetracycline (TC) under visible light irradiation. The capturing experiments and electron spin resonance (ESR) confirmed that the hinge for the enhanced performance of this system is the superior H2O2 yield (499 µM) through the oxygen reduction process (ORR) of the two-step single-electron over the resin and the high concentration of •OH due to activation effect of RM. In addition, the Fe2+/Fe3+ cycles are accelerated by photoelectrons to effectively initiate the photo-self-Fenton reaction. Finally, the possible degradation pathways were proposed via liquid chromatography-mass spectrometry (LC-MS). This study provides a new idea for environmental recovery in a waste-based heterogeneous photocatalytic self-Fenton system.

Construction of a turn-on fluorescent probe for detecting formaldehyde in biological systems and real food samples.

The monitoring of formaldehyde (FA) in biosystems and real foods is critical for ensuring human health and food safety. However, the development of effective and highly selective assays for sensing FA in organisms and real food samples remains challenging. Herein, a hydrophilic group-modified the probe (Nap-FA) was reported, which utilizes the specific chemical reaction between FA and hydrazino to trigger a "turn-on" fluorescence response. The probe Nap-FA displayed superior selectivity, high sensitivity, good photostability and a low detection limit in the reaction with FA. Notably, Nap-FA has been successfully used for imaging FA in cells, zebrafish, and plant root tissues. In addition, the rationally constructed probe Nap-FA could rapidly and visually detect FA in real food samples. This work provides a prospective approach for monitoring FA in complex biological systems and food fields.

Unidentical Twins: Geometrically Similar but Chemically Distinct Metal-free Sites in Boron Oxide for Methane Oxidation to HCHO, CO and CO2.

Metal-free boron-based catalysts such as boron oxide (B2O3) and boron nitride (h-BN) are promising catalysts for the methane oxidation to HCHO and CO. The B2O3 catalyst contains various probable boron sites (B1 to B6), which may be responsible for methane oxidation. In this work, we utilized density functional theory to compare two relevant geometrically identical boron sites (B2 and B4) for their reactivities. The two sites are explored in-detail for the conversion of methane to formaldehyde (M2F), carbon monoxide and carbon dioxide. The B4 site activates the methane C-H bond easily as compared to the B2 site. In M2F conversion, the rate-determining step for the B2 site is the co-activation of dioxygen and methane, whereas over the B4 site, formaldehyde formation is the rate-determining step. The computationally-determined RDS for the B4 site coincides well with the reported experiments. It is further revealed that this site also prefers the formation of CO over CO2, which is in-line with the experiments in literature. It is also shown through orbital analysis that methanol formation does not occur during methane oxidation. We employed descriptors such as condensed Fukui functions and global electrophilicity index to chemically distinct these twin sites.

Biotransformation of 2-keto-4-hydroxybutyrate via aldol condensation using an efficient and thermostable carboligase from Deinococcus radiodurans.

The bioconversion of 4-hydroxy-2-keto acid derivatives via aldol condensation of formaldehyde and pyruvate has received substantial attention as potential source of chemicals for production of amino acids, hydroxy carboxylic acids, and chiral aldehydes. We developed an environmentally friendly biocatalyst consisting of a novel thermostable class II pyruvate aldolase from Deinococcus radiodurans with maltose-binding protein (MBP-DrADL), which has specific activity of 46.3 µmol min-1 mg-1. Surprisingly, MBP-DrADL maintained over 60% of enzyme activity for 4 days at 50 to 65 °C, we used MBP-DrADL as the best candidate enzyme to produce 2-keto-4-hydroxybutyrate (2-KHB) from formaldehyde and pyruvate via aldol condensation. The optimum reaction conditions for 2-KHB production were 50 °C, pH 8.0, 5 mM Mg2+, 100 mM formaldehyde, and 200 mM pyruvate. Under these optimized conditions, MBP-DrADL produced 76.5 mM (8.94 g L-1) 2-KHB over 60 min with a volumetric productivity of 8.94 g L-1 h-1 and a specific productivity of 357.6 mg mg-enzyme-1 h-1. Furthermore, 2-KHB production was improved by continuous addition of substrates, which produced approximately 124.8 mM (14.6 g L-1) of 2-KHB over 60 min with a volumetric productivity and specific productivity of 14.6 g L-1 h-1 and 583.4 mg mg-enzyme-1 h-1, respectively. MBP-DrADL showed the highest specific productivity for 2-KHB production yet reported. Our study provides a highly efficient biocatalyst for the synthesis of 2-KHB and lays the foundation for large-scale production and application of high-value compounds from formaldehyde.

Triangulation of epidemiological evidence and risk of bias evaluation: A proposed framework and applied example using formaldehyde exposure and risk of myeloid leukemias.

Evidence triangulation may help identify the impact of study design elements on study findings and to tease out biased results when evaluating potential causal relationships; however, methods for triangulating epidemiologic evidence are evolving and have not been standardized. Building upon key principles of epidemiologic evidence triangulation and risk of bias assessment, and responding to the National Academies of Sciences, Engineering, and Medicine (NASEM) call for applied triangulation examples, the objective of this manuscript is to propose a triangulation framework and to apply it as an illustrative example to epidemiologic studies examining the possible relationship between occupational formaldehyde exposure and risk of myeloid leukemias (ML) including acute (AML) and chronic (CML) types. A nine-component triangulation framework for epidemiological evidence was developed incorporating study quality and ROB guidance from various federal health agencies (i.e., US EPA TSCA and NTP OHAT). Several components of the triangulation framework also drew from widely used epidemiological analytic tools such as stratified meta-analysis and sensitivity analysis. Regarding the applied example, fourteen studies were identified and assessed using the following primary study quality domains to explore potential key sources of bias: 1) study design and analysis; 2) study participation; 3) exposure assessment; 4) outcome assessment; and 5) potential confounding. Across studies, methodological limitations possibly contributing to biased results were observed within most domains. Interestingly, results from one study - often providing the largest and least-precise relative risk estimates, likely reflecting study biases, deviated from most primary study findings indicating no such associations. Triangulation of epidemiological evidence appears to be helpful in exploring inconsistent results for the identification of study results possibly reflecting various biases. Nonetheless, triangulation methodologies require additional development and application to real-world examples to enhance objectivity and reproducibility.

Bimetallic Au and Pd Nanoparticles Modified WO3 Nanosheets for Enhancing the Sensitivity and Selectivity of Formaldehyde Assessment in Aquatic Products.

Formaldehyde, a common illegal additive in aquatic products, poses a threat to people's health and lives. In this study, a novel metal oxide semiconductor gas sensor based on AuPd-modified WO3 nanosheets (NSs) had been developed for the highly efficient detection of formaldehyde. WO3 NS modified with 2.0% AuPd nanoparticles showed a higher response (Ra/Rg = 94.2) to 50 ppm of formaldehyde at 210 °C, which was 36 times more than the pristine WO3 NS. In addition, the AuPd/WO3 gas sensor had a relatively short response/recovery time of 10 s/9 s for 50 ppm of formaldehyde at 210 °C, with good immunity to other interfering gases and good stability for formaldehyde. The excellent gas-sensitive performance was attributed to the chemical sensitization of Au, the electronic sensitization of Pd, and the synergistic effect of bimetallic AuPd, which facilitated the recognition and response of formaldehyde molecules. Additionally, the high sensitivity and broad application prospect of the 2.0% AuPd/WO3 NS composite-based sensor in real sample detection were also confirmed by using the above sensor for the detection of formaldehyde in aquatic products such as squid and shrimp.

Design of a synthetic enzyme cascade for the in vitro fixation of formaldehyde to acetoin.

Formaldehyde (FALD) has gained prominence as an essential C1 building block in the synthesis of valuable chemicals. However, there are still challenges in converting FALD into commodities. Recently, cell-free biocatalysis has emerged as a popular approach for producing such commodities. Acetoin, also known as 3-hydroxy-2-butanone, has been widely used in food, cosmetic, agricultural and the chemical industry. It is valuable to develop a process to produce acetoin from FALD. In this study, a cell-free multi-enzyme catalytic system for the production of acetoin using FALD as the substrate was designed and constructed. It included three scales: FALD utilization pathway, glycolysis pathway and acetoin synthesis pathway. After the optimization of the reaction system, 20.17 mM acetoin was produced from 122 mM FALD, with a yield of 0.165 mol/mol, reaching 99.0% of the theoretical yield. The pathway provides a new approach for high-yield acetoin production from FALD, which consolidates the foundation for the production of high value-added chemicals using cheap one-carbon compounds.