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Internal finishing materials for large auditoriums or public facilities are regulated in South Korea to ensure their flame-retardant performance. Flame-retardant treatment of low-density fiberboard (LDF), an eco-friendly material, was performed to expand its use as a sound absorber by improving its fire safety. In this study, an LDF with a target density of 0.15 g/cm3 was prepared from radiata pine wood fibers and melamine–urea– formaldehyde resin, and recommended amounts of commercially available flame retardants (liquid type) were applied immediately after hot pressing. A powder-type flame retardant was blended with the resin used in LDF manufacture. The surface color and material changed partially depending on the flame-retardant type. The external application method slightly increased the moisture content and density, but it did not affect the physical properties of the LDF. The flame-retardant treatment reduced the emission of formaldehyde, as a scavenger. After treatment, the char area and char length of the LDFs decreased significantly to 9.42–23.64%, and 6.11–11.91%, respectively. The sound absorption performance of the flame-retardant-treated LDFs improved 4.08–9.11%, while their thermal-insulation performance remained unaffected. The flame-retardant-treated LDFs satisfy the regulation of flame retardancy, while maintaining sound absorption and thermal insulation functions. [ABSTRACT FROM AUTHOR]

Settled house dust (SHD) is a reservoir for various contaminants, including endocrine‐disrupting chemicals (EDCs), trace metals, and house dust mite allergens. This study aimed to characterize various chemical and biological contaminants in SHD and identify determinants governing the indoor contaminants. In total, 106 SHD samples were collected from 106 houses in Seoul and Gyeonggi Province, Korea, in 2021. Bedding dust samples were collected from 30 of these 106 houses. All participants completed a questionnaire comprised of housing and lifestyle‐related factors. The samples were analyzed for 18 organophosphate flame retardants (OPFRs), 16 phthalates, five alternative plasticizers (APs), seven trace metals, and two house dust mite allergens (Dermatophagoides farinae type 1 [Der f1] and Dermatophagoides pteronyssinus type 1 [Der p1]). A multiple regression analysis was conducted to identify the determinants governing the concentrations and profiles of various contaminants. OPFRs, phthalates, APs, and trace metals were detected in all SHD samples, indicating ubiquitous contamination in indoor environments. Among the three EDC groups, APs were detected at the highest concentrations (geometric mean [GM] (geometric standard deviation, [GSD]): 1452 (1.6) μg/g in total), followed by phthalates (GM (GSD): 676 (1.4) μg/g in total) and OPFRs (GM (GSD): 10 (1.4) μg/g in total). Der f1 was detected in all bedding dust samples with significantly higher levels than Der p1 (GM (GSD): 0.1 (1.8) μg/g vs. 1.4 × 10−3 (2.3) μg/g). The concentrations of OPFRs, plasticizers, and trace metals in SHD were significantly associated with the type and number of electronic appliances and combustion activities. Der f1 was significantly associated with the number of occupants and water penetration. Ventilation, vacuum cleaning, and wet cleaning or dry mopping significantly reduced the levels of most contaminants in SHD. As residents are persistently exposed to a wide array of pollutants, comprehensive and adequate measures are required to prevent potential exposures. [ABSTRACT FROM AUTHOR]

In excess of 13,000 chemicals are added to plastics ('additives') to improve performance, durability, and production of plastic products. They are categorized into numerous chemical classes including flame retardants, light stabilizers, antioxidants, and plasticizers. While research on plastic additives in the marine environment has increased over the past decade, there is a lack of methodological standardization. To direct future measurement of plastic additives, we compiled a first-of-its-kind dataset of literature assessing plastic additives in marine environments, delineated by sample type (plastic debris, seawater, sediment, biota). Using this dataset, we performed a meta-analysis to summarize the state of the science. Currently, our dataset includes 217 publications published between 1978 and May 2023. The majority of publications analyzed plastic additives in biota collected from Europe and Asia. Analyses concentrated on plasticizers, brominated flame retardants, and bisphenols. Common sample preparation techniques included Solvent - Agitation extraction for plastic, sediment, and biota samples, and Solid Phase Extraction for seawater samples with dichloromethane and solvent mixtures including dichloromethane as the organic extraction solvent. Finally, most analyses were performed utilizing gas chromatography/mass spectrometry. There are a variety of data gaps illuminated by this meta-analysis, most notably the small number of compounds that have been targeted for detection compared to the large number of additives used in plastic production. The provided dataset facilitates future investigation of trends in plastic additive concentration data in the marine environment (allowing for comparison to toxicity thresholds) and acts as a starting point for optimizing and harmonizing plastic additive analytical methods. [Display omitted] • First comprehensive dataset of plastic additives measured in the ocean is utilized. • Samples mainly analyzed for phthalates, brominated flame retardants, and bisphenols. • Gas chromatography/mass spectrometry is the dominant detection method. • HBCD concentrations are highest in polystyrene samples from South Korea. • More method comparison studies are needed to improve standardization in the field. [ABSTRACT FROM AUTHOR]

Legacy and alternative halogenated flame retardants (HFRs), such as polybrominated diphenyl ethers (PBDEs), novel brominated flame retardants (NBFRs), and dechlorane plus (DP), were measured in dated sediments from a highly industrialized lake in Korea. All HFRs were detected in almost all of the sediment depth layers for more than 70 years, indicating a history of long-term contamination. Similar historical trends in PBDEs, 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), and DP were observed in dated sediments, whereas decabromodiphenylethane (DBDPE), and 2-ethylhexyl-2,3,4,5-octabromo-1,3,3-trimethyl-1-phenylindane (OBIND) concentrations sharply increased since the 1990s. Moreover, the concentration ratios of DBDPE/BDE 209 increased from the early 1990s to the present. Our findings suggest that DBDPE and OBIND have been used as HFR alternatives. The historical record of the concentrations and profiles of legacy and alternative HFRs corresponded with industrial activities, consumption of FRs, and coastal development activities. Inventories of legacy and alternative HFRs were similar to those reported for highly industrialized regions around the globe. [Display omitted] • Legacy and alternative HFRs were detected in an industrialized lake for a period >70 years. • BTBPE and DP were historically consumed along with PBDEs. • DBDPE and OBIND levels increased since the regulations on PBDEs in dated sediment. • Increasing ratios of DBDPE/BDE 209 over time indicate a shift in HFR consumption patterns. • Historical trends in HFRs were influenced by industrial and coastal development activities. [ABSTRACT FROM AUTHOR]

Novel halogenated flame retardants (HFRs) were introduced to industrial markets as alternatives to legacy brominated FRs (BFRs), such as polybrominated diphenyl ethers (PBDEs). In the present study, PBDEs and their brominated and chlorinated alternatives, novel BFRs (NBFRs) and dechlorane plus (DP), were measured in multiple environmental matrices in a highly industrialized lake in Korea. Legacy and novel HFRs were detected in multiple samples, indicating ubiquitous contamination. Concentrations of HFRs in water and sediment observed in creeks running through machine, textiles, and automobile industrial complexes were significantly higher than those observed in inside and outside of the lake. Higher bioaccumulation levels of HFRs were observed in inshore compared with offshore waters. Results suggest that multi-matrix distribution of legacy and novel HFRs was dependent on the geographical proximity to industrial sources. Compared with previous studies, the highest levels of PBDEs and NBFRs were recorded in water samples on a global scale, implying on-going emissions from industrial activities. Decabromodiphenyl ethane (DBDPE) was a dominant compound in water samples, whereas the concentrations of PBDEs, NBFRs, and DP in sediment were similar to each other. This suggests a shift in consumption from legacy to novel HFRs, preferentially in water environments. A significant declining trend in PBDEs was observed in water and sediment collected between 2008 and 2015, indicating the effectiveness of regulatory actions. Based on their environmental occurrence and bioaccumulation potential, pentabromoethylbenzene and bis(2-ethylhexyl) tetrabromophthalate may pose emerging concerns regarding contamination of aquatic environments. [Display omitted] • Severe contamination by novel BFRs was observed in creeks running through industrial complexes. • Predominant HFRs in water samples was DBDPE, an alternative of deca-BDE. • Proximity to industrial complexes is crucial for multi-matrix distribution of HFRs. • A significant declining trend in PBDEs indicated the effectiveness of regulatory actions. • PBEB and BEHTBP were suggested as environmental contaminants of emerging concerns. [ABSTRACT FROM AUTHOR]