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Chemosphere Sep 2023Insecticides are widely used in crop protection against insects and frequently detected in aquatic environment. Photolysis kinetics are directly related with exposure...
Insecticides are widely used in crop protection against insects and frequently detected in aquatic environment. Photolysis kinetics are directly related with exposure assessment and risk assessment. However, the photolysis mechanism of neonicotinoid insecticides with different structures has not been studied and compared systematically in the literature. In this paper, the photolysis rate constants in water were determined for eleven insecticides under irradiation of simulated sunlight. At the same time, the photolysis mechanism and effect of dissolved organic matter (DOM) on their photolysis were studied. The results showed that photolysis rates of eleven insecticides vary in a large range. The photolysis rates of nitro-substituted neonicotinoids and butenolide insecticide are much faster than that of cyanoimino-substituted neonicotinoids and sulfoximine insecticide. The ROS scavenging activity assays reveal that direct photolysis dominates the degradation of seven insecticides and, on the other hand, self-sensitized photolysis dominates four insecticides. The shading-effect from DOM can reduce the direct photolysis rates, on the other hand, ROSs generated by triplet-state DOM (DOM*) can also accelerate photolysis of insecticides. According to the photolytic products identified from HPLC-MS, these eleven insecticides have different photolysis pathways. Six insecticides are degraded from the removal of nitro group from their parent compounds and four insecticides are degraded through ·OH reaction or singlet oxygen (O) reaction. QSAR (quantitative structure-activity relationship) analysis showed that photolysis rate was directly related to the energy gap between the highest occupied molecular orbital to the lowest unfilled molecular orbital (E = E-E) and dipole moment (δ). These two descriptors reflect the chemical stability and reactivity of insecticides. The pathways developed from identified products and the molecular descriptors of QSAR models can well verify the photolysis mechanisms of eleven insecticides.
Topics: Kinetics; Insecticides; Quantitative Structure-Activity Relationship; Photolysis; Sunlight; Neonicotinoids; Water Pollutants, Chemical
PubMed: 37211161
DOI: 10.1016/j.chemosphere.2023.138968 -
The Science of the Total Environment Nov 2023The presence of antibiotics in surface waters is a potential driver of antibiotic resistance and thus of concern to human and environmental health. Key factors driving... (Review)
Review
The presence of antibiotics in surface waters is a potential driver of antibiotic resistance and thus of concern to human and environmental health. Key factors driving the potential impact of antibiotics are their persistence and transport in rivers and lakes. The goal of this study was to describe the peer-reviewed published literature on the photolysis (direct and indirect), sorption, and biodegradation of a selected group of antibiotic compounds following a scoping review methodology. Primary research from 2000 to 2021 was surveyed to compile information on these processes for 25 antibiotics from 6 classes. After compilation and assessment of the available parameters, the results indicate that information is present to predict the rates of direct photolysis and reaction with hydroxyl radical (an indirect photolysis process) for most of the selected antibiotics. There is insufficient or inconsistent information for including other indirect photolysis processes, biodegradation, or removal via sorption to settling particles for most of the targeted antibiotic compounds. Future research should focus on collecting fundamental parameters such as quantum yields, second-order rate constants, normalized biodegradation rates, and organic carbon or surface area normalized sorption coefficients rather than pseudo-first order rate constants or sorption equilibrium constants that apply only to specific conditions/sites.
Topics: Humans; Anti-Bacterial Agents; Photolysis; Water Pollutants, Chemical; Biodegradation, Environmental
PubMed: 37414169
DOI: 10.1016/j.scitotenv.2023.165301 -
Biodegradation Aug 2023Sulfoxaflor (SUL, [N-[methyloxido[1-[6-(trifluoromethyl)-3-pyridinyl] ethyl]-λ-sulfanylidene] cyanamide]) is a widely used systemic insecticide, and its residue has...
Sulfoxaflor (SUL, [N-[methyloxido[1-[6-(trifluoromethyl)-3-pyridinyl] ethyl]-λ-sulfanylidene] cyanamide]) is a widely used systemic insecticide, and its residue has frequently been detected in the environment, posing a potential threat to the environment. In this study, Pseudaminobacter salicylatoxidans CGMCC 1.17248 rapidly converted SUL into X11719474 via a hydration pathway mediated by two nitrile hydratases (AnhA and AnhB). Extensive (96.4%) degradation of 0.83 mmol/L SUL was achieved by P. salicylatoxidans CGMCC 1.17248 resting cells within 30 min (half-life of SUL 6.4 min). Cell immobilization by entrapment into calcium alginate remediated 82.8% of the SUL in 90 min, and almost no SUL was observed in surface water after incubation for 3 h. P. salicylatoxidans NHases AnhA and AnhB both hydrolyzed SUL to X11719474, although AnhA exhibited much better catalytic performance. The genome sequence of P. salicylatoxidans CGMCC 1.17248 revealed that this strain could efficiently eliminate nitrile-containing insecticides and adapt to harsh environments. We firstly found that UV irradiation transforms SUL to the derivatives X11719474 and X11721061, and the potential reaction pathways were proposed. These results further deepen our understanding of the mechanisms of SUL degradation as well as the environmental fate of SUL.
Topics: Ultraviolet Rays; Photolysis; Insecticides; Biodegradation, Environmental
PubMed: 36808271
DOI: 10.1007/s10532-023-10020-x -
Environmental Monitoring and Assessment Jul 2023This review highlights various experimental and mathematical modeling strategies to investigate the fate and transport of antibiotics that elucidate antimicrobial... (Review)
Review
This review highlights various experimental and mathematical modeling strategies to investigate the fate and transport of antibiotics that elucidate antimicrobial selective pressure in aquatic environments. Globally, the residual antibiotic concentrations in effluents from bulk drug manufacturing industries were 30- and 1500-fold greater than values reported in municipal and hospital effluents, respectively. The antibiotic concentration from different effluents enters the waterbodies that usually get diluted as they go downstream and undergo various abiotic and biotic reactive processes. In aquatic systems, photolysis is the predominant process for antibiotic reduction in the water matrix, while hydrolysis and sorption are frequently reported in the sediment compartment. The rate of antibiotic reduction varies widely with influencing factors such as the chemical properties of the antibiotics and hydrodynamic conditions of river streams. Among all, tetracycline was found to more unstable (log K = - 0.62 to - 1.12) that can readily undergo photolysis and hydrolysis; whereas macrolides were more stable (log K = 3.06 to 4.02) that are prone to biodegradation. The processes like photolysis, hydrolysis, and biodegradation followed first-order reaction kinetics while the sorption followed a second-order kinetics for most antibiotic classes with reaction rates occurring in the decreasing order of Fluoroquinolones and Sulphonamides. The reports from various experiments on abiotic and biotic processes serve as input parameters for an integrated mathematical modeling to predict the fate of the antibiotics in the aquatic environment. Various mathematical models viz. Fugacity level IV, RSEMM, OTIS, GREAT-ER, SWAT, QWASI, and STREAM-EU are discussed for their potential capabilities. However, these models do not account for microscale interactions of the antibiotics and microbial community under real-field conditions. Also, the seasonal variations for contaminant concentrations that exert selective pressure for antimicrobial resistance has not been accounted. Addressing these aspects collectively is the key to exploring the emergence of antimicrobial resistance. Therefore, a comprehensive model involving antimicrobial resistance parameters like fitness cost, bacterial population dynamics, conjugation transfer efficiency, etc. is required to predict the fate of antibiotics.
Topics: Anti-Bacterial Agents; Environmental Monitoring; Fluoroquinolones; Rivers; Models, Theoretical; Water Pollutants, Chemical
PubMed: 37436551
DOI: 10.1007/s10661-023-11482-5 -
Journal of Biophotonics Nov 2023Hematomas resulted from trauma are very common, and the efficacy of existing treatment techniques is limited. Phototherapy can be used to expedite healing and improve...
Hematomas resulted from trauma are very common, and the efficacy of existing treatment techniques is limited. Phototherapy can be used to expedite healing and improve the appearance of the damaged tissue. Efficient phototherapy requires determination of chromophore composition in hematoma, which can be provided by the optoacoustic (OA) technique, as it combines high spatial resolution and optical contrast. Here, we conducted experiments on photodegradation of bilirubin in gelatin slin phantoms. We have demonstrated that the OA technique allows monitoring of bilirubin concentration during photodegradation, and also distinguishing bilirubin concentration in depth. The obtained results suggest that OA monitoring may be used for efficient hematoma phototherapy.
Topics: Humans; Bilirubin; Photolysis; Phototherapy; Photoacoustic Techniques; Hematoma
PubMed: 37345342
DOI: 10.1002/jbio.202200339 -
Nature Chemistry Oct 2023Formaldehyde, HCHO, is the highest-volume carbonyl in the atmosphere. It absorbs sunlight at wavelengths shorter than 330 nm and photolyses to form H and HCO radicals,...
Formaldehyde, HCHO, is the highest-volume carbonyl in the atmosphere. It absorbs sunlight at wavelengths shorter than 330 nm and photolyses to form H and HCO radicals, which then react with O to form HO. Here we show HCHO has an additional HO formation pathway. At photolysis energies below the energetic threshold for radical formation we directly detect HO at low pressures by cavity ring-down spectroscopy and indirectly detect HO at 1 bar by Fourier-transform infrared spectroscopy end-product analysis. Supported by electronic structure theory and master equation simulations, we attribute this HO to photophysical oxidation (PPO): photoexcited HCHO relaxes non-radiatively to the ground electronic state where the far-from-equilibrium, vibrationally activated HCHO molecules react with thermal O. PPO is likely to be a general mechanism in tropospheric chemistry and, unlike photolysis, PPO will increase with increasing O pressure.
PubMed: 37414879
DOI: 10.1038/s41557-023-01272-4 -
Journal of Hazardous Materials Oct 2023Three novel neonicotinoids (cycloxaprid, flupyradifurone and sulfoxaflor) were designed to reduce the biotoxicity for non-target organisms. These neonicotinoids were...
Three novel neonicotinoids (cycloxaprid, flupyradifurone and sulfoxaflor) were designed to reduce the biotoxicity for non-target organisms. These neonicotinoids were photolyzed under light radiation, but it was unclear for the photo-enhanced toxicity and influences of the novel modifying group of the three neonicotinoids. The photolysis and photo-enhanced toxicity experiments were performed for the three neonicotinoids, coupled with quantum chemistry calculation, the mechanisms of photolysis, photo-enhanced toxicity and the influences of novel modifying groups were analyzed. The results showed the photolysis pathways were enriched as compared with previous neonicotinoids due to the composition of modifying groups, singlet oxygen and hydroxyl participated the photolysis of cycloxaprid and flupyradifurone. All tested neonicotinoids exhibited photo-enhanced toxicity to Vibrio fischeri. Due to the difference of photolysis mechanism and toxicity to V. fischeri, the photo-enhanced toxicity curves showed diverse variation when histidine, tert-butanol or dissolved organic matters was in presence of the test solutions. The impact of novel modifying groups over photolysis and photo-enhanced toxicity were analyzed based on the comparison with previous neonicotinoids, theoretically predicted UV-Vis spectra and photo-physical/chemical property descriptors. The data showed the composition of novel modifying group increased the light absorption and photo-chemical activities for the three neonicotinoids.
Topics: Photolysis; Neonicotinoids; 4-Butyrolactone; Water Pollutants, Chemical; Aliivibrio fischeri
PubMed: 37494794
DOI: 10.1016/j.jhazmat.2023.132132 -
Advanced Healthcare Materials Apr 2024The emerging field of photopharmacology is a promising chemobiological methodology for optical control of drug activities that could ultimately solve the off-target... (Review)
Review
The emerging field of photopharmacology is a promising chemobiological methodology for optical control of drug activities that could ultimately solve the off-target toxicity outside the disease location of many drugs for the treatment of a given pathology. The use of photolytic reactions looks very attractive for a light-activated drug release but requires to develop photolytic reactions sensitive to red or near-infrared light excitation for better tissue penetration. This review will present the concepts of triplet-triplet annihilation upconversion-based photolysis and their recent in vivo applications for light-induced drug delivery using photoactivatable nanoparticles.
PubMed: 38613491
DOI: 10.1002/adhm.202400354 -
ACS ES&T Water Aug 2023The susceptibility of 19 representative per- and polyfluoroalkyl substances (PFAS) to direct photolysis and defluorination under far-UVC 222 nm irradiation was...
The susceptibility of 19 representative per- and polyfluoroalkyl substances (PFAS) to direct photolysis and defluorination under far-UVC 222 nm irradiation was investigated. Enhanced photolysis occurred for perfluorocarboxylic acids (PFCAs), fluorotelomer unsaturated carboxylic acids (FTUCAs), and GenX, compared to that at conventional 254 nm irradiation on a similar fluence basis, while other PFAS showed minimal decay. For degradable PFAS, up to 81% of parent compound decay (photolysis rate constant () = 8.19-34.76 L·Einstein; quantum yield (Φ) = 0.031-0.158) and up to 31% of defluorination were achieved within 4 h, and the major transformation products were shorter-chain PFCAs. Solution pH, dissolved oxygen, carbonate, phosphate, chloride, and humic acids had mild impacts, while nitrate significantly affected PFAS photolysis/defluorination at 222 nm. Decarboxylation is a crucial step of photolytic decay. The slower degradation of short-chain PFCAs than long-chain ones is related to molar absorptivity and may also be influenced by chain-length dependent structural factors, such as differences in p, conformation, and perfluoroalkyl radical stability. Meanwhile, theoretical calculations indicated that the widely proposed HF elimination from the alcohol intermediate (CFOH) of PFCA is an unlikely degradation pathway due to high activation barriers. These new findings are useful for further development of far-UVC technology for PFAS in water treatment.
PubMed: 37588805
DOI: 10.1021/acsestwater.3c00274 -
Photochemical & Photobiological... Mar 2024Antibiotics development during the last century permitted unprecedent medical advances. However, it is undeniable that there has been an abuse and misuse of... (Review)
Review
Antibiotics development during the last century permitted unprecedent medical advances. However, it is undeniable that there has been an abuse and misuse of antimicrobials in medicine and cosmetics, food production and food processing, in the last decades. The pay toll for human development and consumism is the emergence of extended antimicrobial resistance and omnipresent contamination of the biosphere. The One Health concept recognizes the interconnection of human, environmental and animal health, being impossible alter one without affecting the others. In this context, antibiotic decontamination from water-sources is of upmost importance, with new and more efficient strategies needed. In this framework, light-driven antibiotic degradation has gained interest in the last few years, strongly relying in semiconductor photocatalysts. To improve the semiconductor properties (i.e., efficiency, recovery, bandgap width, dispersibility, wavelength excitation, etc.), bio-based supporting material as photocatalysts matrices have been thoroughly studied, exploring synergetic effects as operating parameters that could improve the photodegradation of antibiotics. The present work describes some of the most relevant advances of the last 5 years on photodegradation of antibiotics and other antimicrobial molecules. It presents the conjugation of semiconductor photocatalysts to different organic scaffolds (biochar and biopolymers), then to describe hybrid systems based on g-CN and finally addressing the emerging use of organic photocatalysts. These systems were developed for the degradation of several antibiotics and antimicrobials, and tested under different conditions, which are analyzed and thoroughly discussed along the work.
Topics: Animals; Humans; Anti-Bacterial Agents; Photolysis; Catalysis; Anti-Infective Agents
PubMed: 38400987
DOI: 10.1007/s43630-024-00536-3