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PubMed2026

Engineering copper ferrite (CuFe2O4) nanocomposites for enhanced eco-friendly photocatalysis: a systematic critical review on mechanisms, performance, and environmental applications.

Water pollution caused by organic and inorganic contaminants, particularly dyes and pharmaceuticals, represents a major environmental challenge. Advanced oxidation processes based on photocatalysts have emerged as efficient and sustainable approaches for water and wastewater treatment. Copper ferrite (CuFe2O4) is considered a promising photocatalyst owing to its narrow bandgap, visible-light activity, chemical stability, and magnetic properties. Despite extensive experimental investigations, a comprehensive systematic comparison of CuFe2O4-based photocatalysts under diverse operational conditions has remained limited. In this study, a systematic review following PRISMA guidelines was conducted using studies published between January 2014 and November 2025 indexed in Scopus, PubMed, Web of Science, and ScienceDirect. From an initial pool of 397 studies, 98 articles met the inclusion criteria. Key parameters - including pollutant type, pH, catalyst dosage, initial pollutant concentration, irradiation time, light source, and degradation efficiency - were quantitatively compared to identify performance trends and operational optima. The results demonstrate that CuFe2O4-based nanocomposites, particularly heterojunction, Z-scheme, and S-scheme architectures combined with TiO2, g-C3N4, graphene, and metal oxides, achieve high degradation efficiencies (often >90 %) for a wide range of organic pollutants and selected inorganic contaminants (e.g., Cr(VI)). Enhanced charge separation and suppressed electron-hole recombination were identified as the primary factors contributing to improved photocatalytic activity. In addition, the intrinsic magnetic properties of these nanocomposites enable facile catalyst recovery and reuse. In conclusion, CuFe2O4-based nanocomposites, especially those incorporating advanced heterojunction architectures, emerge as highly efficient and magnetically recoverable photocatalytic platforms for sustainable water and wastewater treatment, with strong potential for scalable implementation and real-wastewater applications.

Catalysis↗
PubMed2004

Sources of fine particulate matter in personal exposures and residential indoor, residential outdoor and workplace microenvironments in the Helsinki phase of the EXPOLIS study.

OBJECTIVES: This study assessed the source contributions to the mass concentrations of fine particles (PM2.5) in personal exposures and in residential indoor, residential outdoor, and workplace indoor microenvironments of the nonsmoking adult population unexposed to environmental tobacco smoke in Helsinki, Finland. METHODS: The elemental composition of 48-hour personal exposure and residential indoor, residential outdoor, and workplace indoor PM2.5 was analyzed by energy-dispersive X-ray fluorescence spectrometry for 76 participants not exposed to environmental tobacco smoke and 102 participating residences with no smoking in Helsinki as a part of the EXPOLIS study. Subsequently, a principal component analysis was used to identify the emission sources of PM2.5-bound elements and black smoke in each microenvironment, and this information was used to identify the corresponding sources in personal exposures. Finally, source reconstruction was done to determine the relative contributions of each source type to the total PM2.5 mass concentrations. RESULTS: Inorganic secondary particles, primary combustion, and soil were the dominant source types for the PM2.5 mass concentration in all the microenvironments and personal exposures. The ratio of the residential indoor-to-outdoor PM2.5 concentration was close to unity, but the corresponding elemental ratios and source contributions varied. Resuspension of soil dust tracked indoors was a much larger contributor to residential and workplace indoor PM2.5 than soil dust to residential outdoor PM2.5. Source contributions to personal PM2.5 exposures were best approximated by data from residential and workplace indoor microenvironments. CONCLUSIONS: Population exposure assessment of PM2.5, based on outdoor fixed-site monitoring, overestimates exposures to outdoor sources like traffic and long-range transport and does not account for the contribution of significant indoor sources.

Adult↗
PubMed2002

Particle size relationships at the Fresno Supersite.

Aerosol size distributions are presented for a winter intensive study at the Fresno Supersite. The size distributions were consistent with and predictive for continuous PM2.5 measured by beta attenuation. They varied temporally with respect to source type and intensity, with the smallest mean diameters associated with high NOx concentrations during weekday morning rush hours. Conversely, small and large particle and black carbon (BC) concentrations were higher during Sunday and weekday evenings in response to traffic and residential wood combustion emissions. Ambient PM2.5 light scattering (Bsp) was precisely but systematically underestimated during winter, probably because of heating in the sample shelter.

Aerosols↗
PubMed1989

[Epidemiological problems of non-occupational exposure to asbestos dust].

We have presently a sufficient amount of evidence based on epidemiological and experimental investigations to regard asbestos as a carcinogen in human environment. The use of asbestos-containing products and asbestos pollution of the natural environment of man are the risk factors for neoplasms in the general population. The sources of pollution and the values of asbestos dust concentration in community environment and the estimation of the risk related to asbestos dust are presented in the light of epidemiological and ecological studies.

Air Pollutants↗
PubMed2004

Reconsidering the use of photosynthetic bacteria for removal of sulfide from wastewater.

The feasibility of using photosynthetic sulfide-oxidizing bacteria to remove sulfide from wastewater in circumstances where axenic cultures are unrealistic has been completely reconsidered on the basis of known ecophysiological data, and the principles of photobioreactor and chemical reactor engineering. This has given rise to the development of two similar treatment concepts relying on biofilms dominated by green sulfur bacteria (GSB) that develop on the exterior of transparent surfaces suspended in the wastewater. The GSB are sustained and selected for by radiant energy in the band 720-780 nm, supplied from within the transparent surface. A model of one of these concepts was constructed and with it the reactor concept was proven. The dependence of sulfide-removal rate on bulk sulfide concentration has been ascertained. The maximum net areal sulfide removal rate was 2.23 g m-(2) day-(1) at a bulk sulfide concentration of 16.5 mg L(-1) and an incident irradiance of 1.51 W m(-2). The system has a demonstrated capacity to mitigate surges in sulfide load, and appears to use much less radiant power than comparable systems. The efficacy with which this energy was used for sulfide removal was 1.47 g day(-1) W(-1). The biofilm was dominated by GSB, and evidence gathered indicated that other types of phototrophs were not present.

Biodegradation, Environmental↗
PubMed2005

Effects of acetate and propionate on the performance of a photosynthetic biofilm reactor for sulfide removal.

The effects of acetate and propionate on the performance of a recently proposed and characterized photosynthetic biological sulfide removal system have been investigated with a view to predicting this concept's suitability for removing sulfide from wastewater undergoing or having undergone anaerobic treatment. The concept relies on substratum-irradiated biofilms dominated by green sulfur bacteria (GSB), which are supplied with radiant energy in the band 720-780 nm. A model reactor was fed for 7 months with a synthetic wastewater free of volatile fatty acids (VFAs), after which time intermittent dosing of the wastewater with acetate or propionate was begun. Such dosing suppressed the areal net sulfide removal rate by approximately 50%, and caused the principal net product of sulfide removal to switch from sulfate to elemental-S. Similarly suppressed values of this rate were observed when the wastewater was dosed continuously with acetate, and this rate was not significantly affected by changes in the concentration of ammonia-N in the feed. The main net product of sulfide removal was again elemental-S, which was scarcely released into the liquid, however. Sulfate reduction and sulfur reduction were observed when the light supply was interrupted and were inferred to be occurring within the irradiated biofilm. A preexisting conceptual model of the biofilm was augmented with both of these reductive processes, and this augmented model was shown to account for most of the observed effects of VFA dosing. The implications of these findings for the practicality of the technology are considered.

Acetates↗
PubMed2004

Concentrations of organochlorines in sperm whales (Physeter macrocephalus) from Southern Australian waters.

Concentrations of DDTs, PCBs and HCHs were measured in sperm whales involved in two mass stranding events on the west coast of Tasmania, Australia in February 1998. DDTs and PCBs were present in all samples analysed, while only three contained HCHs. The relationships between organochlorines, sex, age and reproductive groups were marked by high variability. Differences in organochlorine concentrations were observed between animals from the two stranding sites and discussed in light of the ecology of this species. Concentrations of all pollutants were stratified throughout the vertical aspect of the blubber and possible reasons for and the implications of this are discussed. Concentrations of compounds were higher than those documented in this species in the Southern Hemisphere previously, although were relatively lower than those documented in the Northern Hemisphere. However, comparisons were confounded by spatial and temporal differences. Continued monitoring of marine mammals throughout this region in a co-coordinated, standardized manner is essential for establishing definite temporal and spatial variations in pollutant concentrations.

Adipose Tissue↗
PubMed2005

Effects of light and oxygen on the uptake and distribution of phosphorus at the sediment-water interface.

Effects of oxygen and light on the uptake and distribution of phosphorus at the sediment-water interface were investigated in this study. The experimental water and sediment samples were collected from East Taihu Lake, China. The results show that phosphorus can be taken up from the overlying water to the sediments with high nutrient loading in both anoxic and aerobic conditions. The transformation between different phosphorus fractions in the sediments and in the overlying water was observed. Effects of dissolved oxygen on the phosphorus distribution at the sediment and overlying water interface were mainly due to the inorganic processes, while effects of light were mainly due to the biological activity. This study indicates that oxygen concentration had a predominant control on the distribution and uptake of phosphorus in the sediments, and light had obvious effect on the dissolved inorganic phosphorus (DIP) concentration in the overlying water.

China↗
PubMed1998

Kinetics and products of the TiO2 photocatalytic degradation of 2-chlorobiphenyl in water.

The light-induced degradation of 2-chlorobiphenyl (2-CB) under simulated solar irradiation has been investigated in aqueous solutions containing TiO2 suspensions as photocatalysts. The apparent quantum yield for an initial 2-CB concentration C0 = 3.8 micrograms/mL at the natural pH was ca. 0.005 The oxidation kinetics of 2-CB follows the Langmuir-Hinshelwood kinetic model at natural pH. The primary degradation of 2-CB follows a pseudo-first-order kinetics. Several reaction intermediates were identified using GC/FTIR/MS and ion chromatography. The products at the initial stage of the reaction were seven isomers of 2-chlorobiphenyl-ol and biphenyl-2-ol. These intermediates underwent further photocatalytic oxidation via aldehydes, ketones, and acids finally into CO2 and HCl. The formation and fate of some of these compounds under irradiation were also investigated. A reaction scheme involving hydroxyl radicals has been proposed.

Adsorption↗
PubMed2000

Photodegradation of polychlorinated dibenzo-p-dioxins and dibenzofurans in aqueous solutions and in organic solvents.

Aqueous solutions of selected polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were prepared using a generator column and exposed to UV (300 nm) light in the laboratory and to sunlight in an outdoor environment. In the laboratory, additional exposures were also carried out using 60% acetonitrile/water solutions. At 300 nm di- and tetra PCDDs had higher first-order photodegradation rate constants in 60% acetonitrile/water than in pure water. The solvent effect was reversed for PCDFs. These results may be a reflection of the higher polarity of PCDFs compared to PCDDs. In both the indoor and outdoor exposures photodegradation rates decreased with increasing concentrations of chlorination. However, OCDF exposed to 300 nm light in 60% acetonitrile/water and to sunlight in pure water photodegraded more rapidly than tetra CDF. Photolysis rates in sunlight were considerably slower (t(1/2) of 6.4-23 h) than photolysis rates at 300 nm in the laboratory (t(1/2) of 4.3-680 min), reflecting the lower intensity of sunlight in the 300 nm region of the UV/Vis spectrum. The extent of dechlorination of the PCDDs/PCDFs was less than 20% and reductive dechlorination does not appear to be a major process in the photodegradation of PCDDs/PCDFs in aqueous solutions.

Benzofurans↗
PubMed2001

The likely impact of rising atmospheric CO2 on natural and managed Populus: a literature review.

Because of their prominent role in global biomass productivity, as well as their complex structure and function, forests and tree species deserve particular attention in studies on the likely impact of elevated atmospheric CO2 on terrestrial vegetation. Poplar (Populus) has proven to be an interesting study object due to its fast response to a changing environment, and the growing importance of managed forests in the carbon balance. Results of both chamber and field experiments with different poplar species and hybrids are reviewed in this contribution. Despite the variability between experiments and species, and the remaining uncertainty over the long term, poplar is likely to profit from a rising atmospheric CO2 concentration with a mean biomass stimulation of 33%. Environmental conditions and pollutants (e.g. O3) may counteract this stimulation but with managed plantations, environmental constraints might not occur. The predicted responses of poplar to rising atmospheric CO2 have implications for future forest management and the expected forest carbon sequestration.

Air Pollutants↗
PubMed2002

Kinetics and uptake mechanisms for monomethylmercury between freshwater algae and water.

Uptake kinetics of monomethylmercury chloride (MeHgCl) were measured for two species of green algae (Selenastrum capricomutum and Cosmarium botrytis), one blue-green algae (Schizothrix calcicola), and one diatom (Thalassiosira weissflogii), algal species that are commonly found in natural surface waters. Species differences were found with the two green algae giving the highest uptake rates, and one of them (Cosmarium) showing differences between cultures having widely different cell age (exponential versus stationary), where increases in uptake rate for cells 30 days old were about 25 times greater than cells only 3 days old when weights of cells were considered. Both Schizothrix and Thalassiosira exhibited nearly the same lower uptake rates, approximately 20 times lower than the two green algal species. Experiments with photosystem inhibitors, uncouplers, gamma-radiation, light deprivation, and extended range uptake all point to an active transport mechanism for MeHgCl.

Chlorophyta↗
PubMed2003

UV-B damages eyes of barnacle larvae and impairs their photoresponses and settlement success.

The impact of enhanced UV-B radiation on marine ecosystems due to ozone depletion has caused growing global concern. Barnacle larvae have evolved complex photoreceptors and elaborate phototactic behaviors, which enable them to identify suitable habitats for feeding and settlement. For the first time, we demonstrate that environmentally realistic levels of UV-B radiation can induce ocular damage in barnacle larvae, thereby impairing the phototactic behavior of naupliar larvae and reducing settlement success of cypris larvae. Significant disruptions of rhabdomeres (the photosensitive structures in which phototransduction takes place) occurred in the retinular cells of naupliar eyes when naupliar larvae were exposed to a UV-B dose of 7.2 kJ m(-2), and impairment was dependent upon dose rather than irradiance. Our experimental data also showed that phototaxis of nauplii was ca. 4 times more sensitive to UV-B than settlement of cyprids. Since barnacles play an important role in the function and structure of coastal systems worldwide, any impairment of phototactic and settlement behavior of the larvae would pose a significant threat to the sustainability of this ecologically important species. The fact that enhanced UV-B radiation can induce ocular damage and subsequent phototactic impairment in barnacle larvae suggests that UV-B may also cause similar damage to other zooplankton species.

Air Pollutants↗