VOC emitted by biopharmaceutical industries:Source profiles,health risks,and secondary pollution

The biopharmaceutical industry contributes substantially to volatile organic compounds(VOCs)emissions,causing growing concerns and social developmental conflicts.This study conducted an on-site investigation of the process-based emission of VOCs from three biopharmaceutical enterprises.In the workshops of the three enterprises,26 VOCs were detected,which could be sorted into 4 classes:hydrocarbons,aromatic hydrocarbons,oxygen-containing compounds,and nitrogen-containing compounds.Ketones were the main components of waste gases,accounting for 44.13%-77.85%of the overall VOCs.Process-based source profiles were compiled for each process unit,with the fermentation and extraction units of tiamulin fumarate being the main source of VOC emissions.Dimethyl heptanone,vinyl acetate,diethylamine,propylene glycol methyl ether(PGME),and benzene were screened as priority pollutants through a fuzzy comprehensive evaluation system.Ground level concentration simulation results of the Gauss plume diffusion model demonstrated that the diffusivity of VOCs in the atmosphere was relatively high,indicating potential non-carcinogenic and carcinogenic risks 1.5-2 km downwind.Furthermore,the process-based formation potentials of ozone and secondary organic aerosols(SOAs)were determined and indicated that N-methyl-2-pyrrolidone,dimethyl heptanone,and PGME should be preferentially controlled to reduce the ozone formation potential,whereas the control of benzene and chlorobenzene should be prioritized to reduce the generation of SOAs.Our results provide a basis for understanding the characteristics of VOC emission by biopharmaceutical industries and their diffusion,potentially allowing the development of measures to reduce health risks and secondary pollution.

Control of meta-selectivity in the Ir-catalyzed aromatic C-H borylation directed by hydrogen bond interaction:A combined computational and experimental study

The origin of regioselectivity in meta-selective C-H borylation of benzamides directed by hydrogen bond interaction between ligand and substrate is elucidated through combined computational and experimental studies.We discover that a non-directed pathway,in which the urea moiety in ligand recognizes the O atom in Bpin instead of substrate,competes with the directed pathway and erodes the meta-selectivity.The non-directed pathway is sensitive to steric repulsion between Bpin and urea,and thus can be impeded by introducing a bulky substituent into the urea moiety.Accordingly,we optimize the ligand and improve the meta-selectivity in the Ir-catalyzed C-H borylation of some previously reported unsuccessful arenes.

Targeting a novel inducible GPX4 alternative isoform to alleviate ferroptosis and treat metabolic-associated fatty liver disease

Metabolic-associated fatty liver disease(MAFLD),which is previously known as non-alcoholic fatty liver disease(NAFLD),represents a major health concern worldwide with limited therapy.Here,we provide evidence that ferroptosis,a novel form of regulated cell death characterized by iron-driven lipid peroxidation,was comprehensively activated in liver tissues from MAFLD patients.The canonical-GPX4(cGPX4),which is the most important negative controller of ferroptosis,is downregulated at protein but not mRNA level.Interestingly,a non-canonical GPX4 transcript-variant is induced(inducible-GPX4,iGPX4)in MAFLD condition.The high fat-fructose/sucrose diet(HFFD)and methionine/choline-deficient diet(MCD)-induced MAFLD pathologies,including hepatocellular ballooning,steatohepatitis andfibrosis,were attenuated and aggravated,respectively,in cGPX4-and iGPX4-knockin mice.cGPX4 and iGPX4 isoforms also displayed opposing effects on oxidative stress and ferroptosis in hepatocytes.Knockdown of iGPX4 by siRNA alleviated lipid stress,ferroptosis and cell injury.Mechanistically,the triggered iGPX4 interacts with cGPX4 to facilitate the transformation of cGPX4 from enzymatic-active monomer to enzymatic-inactive oligomers upon lipid stress,and thus promotes ferroptosis.Co-immunoprecipitation and nano LC–MS/MS analyses confirmed the interaction between iGPX4 and cGPX4.Our results reveal a detrimental role of non-canonical GPX4 isoform in ferroptosis,and indicate selectively targeting iGPX4 may be a promising therapeutic strategy for MAFLD.

Microbial aerosol particles in four seasons of sanitary landfill site:Molecular approaches,traceability and risk assessment

Landfill sites are regarded as prominent sources of bioaerosols for the surrounding atmosphere.The present study focused on the emission of airborne bacteria and fungi in four seasons of a sanitary landfill site.The main species found in bioaerosols were assayed using high-throughput sequencing.The Source Tracker method was utilized to identify the sources of the bioaerosols present at the boundary of the landfill site.Furthermore,the health consequences of the exposure to bioaerosols were evaluated based on the average daily dose rates.Results showed that the concentrations of airborne bacteria in the operation area(OPA)and the leakage treatment area(LTA)were in the range of(4684±477)–(10883±1395)CFU/m^(3) and(3179±453)–(9051±738)CFU/m^(3),respectively.The average emission levels of fungal aerosols were 4026 CFU/m^(3) for OPA and 1295 CFU/m^(3) for LTA.The landfill site received the maximum bioaerosol load during summer and the minimum during winter.Approximately 41.39%–86.24%of the airborne bacteria had a particle size of 1.1 to 4.7μm,whereas 48.27%–66.45%of the airborne fungi had a particle size of more than 4.7μm.Bacillus sp.,Brevibacillus sp.,and Paenibacillus sp.were abundant in the bacterial population,whereas Penicillium sp.and Aspergillus sp.dominated the fungal population.Bioaerosols released from the working area and treatment of leachate were the two main sources that emerged in the surrounding air of the landfill site boundary.The exposure risks during summer and autumn were higher than those in spring and winter.

Composition,dispersion,and health risks of bioaerosols in wastewater treatment plants:A review

Bioaerosols are defined as airbome particles(0.05-100 um in size)of biological origin.They are considered potentially harmful to human health as they can contain pathogens such as bacteria,fungi,and viruses.This review summarizes the most recent research on the health risks of bioaerosols emitted from wastewater treatment plants(WWTPs)in order to improve the control of such bioaerosols.The concentration and size distribution of WWTP bioaerosols;their major emission sources,composition,and health risks;and considerations for future research are discussed.The major themes and findings in the literature are as follows:the major emission sources of WWTP bioaerosols include screen rooms,sludge-dewatering rooms,and acration tanks;the bioaerosol concentrations in screen and sludge-dewatering rooms are higher than those outdoors.WWTP bioacrosols contain a variety of potentially pathogenic bacteria,fungi,antibiotic resistance genes,viruses,endotoxins,and toxic metal(loid)s.These potentially,pathogenic substances spread with the bioaerosols,thereby posing health risks to workers and residents in and around the WWTP.Inhalation has been identified as the main exposure route,and children are at a higher risk of this than adults.Future studies should identify emerging contaminants,establish health risk assessments,and develop prevention and control systems.

Chemo-, site-selective reduction of nitroarenes under blue-light, catalyst-free conditions

The tandem reaction of photoinduced double hydrogen-atom transfer and deoxygenative transborylation for chemo-and site-selective reduction of nitroarenes into aryl amines under catalyst-free, room temperature conditions was disclosed in excellent yields. In this reaction, isopropanol(^(i)PrOH) was used as hydrogen donor and tetrahydroxydiboron [B_(2)(OH)_(4)] as deoxygenative reagent with green, cheap, and commercially available credentials. In particular, a wide range of reducible functional groups such as halogen(-Cl,-Br and even-I), alkenyl, alkynyl, aldehyde, ketone, carboxyl, and cyano are all tolerated. Moreover,the reaction preferentially reduces the nitro group at the electron-deficient site over another nitro group in the same molecule. A detailed mechanistic investigation in combination of experiments and theoretical calculations gave a reasonable explanation for the reaction pathway.