Emerging contaminants:A One Health perspective

Environmental pollution is escalating due to rapid global development that often prioritizes human needs over planetary health.Despite global efforts to mitigate legacy pollutants,the continuous introduction of new substances remains a major threat to both people and the planet.In response,global initiatives are focusing on risk assessment and regulation of emerging contaminants,as demonstrated by the ongoing efforts to establish the UN’s Intergovernmental Science-Policy Panel on Chemicals,Waste,and Pollution Prevention.This review identifies the sources and impacts of emerging contaminants on planetary health,emphasizing the importance of adopting a One Health approach.Strategies for monitoring and addressing these pollutants are discussed,underscoring the need for robust and socially equitable environmental policies at both regional and international levels.Urgent actions are needed to transition toward sustainable pollution management practices to safeguard our planet for future generations.

Controllable chemical redox reactions to couple microbial degradation for organic contaminated sites remediation:A review

Global environmental concern over organic contaminated sites has been progressively conspicuous during the process of urbanization and industrial restructuring.While traditional physical or chemical remediation technologies may significantly destroy the soil structure and function,coupling moderate chemical degradation with microbial remediation becomes a potential way for the green,economic,and efficient remediation of contaminated sites.Hence,this work systematically elucidates why and how to couple chemical technology with microbial remediation,mainly focused on the controllable redox reactions of organic contaminants.The rational design of materials structure,selective generation of reactive oxygen species,and estimation of degradation pathway are described for chemical oxidation.Meanwhile,current progress on efficient and selective reductions of organic contaminants(i.e.,dechlorination,defluorination,-NO_(2) reduction)is introduced.Combined with the microbial remediation of contaminated sites,several consideration factors of how to couple chemical and microbial remediation are proposed based on both fundamental and practical points of view.This review will advance the understanding and development of chemical-microbial coupled remediation for organic contaminated sites.

Pollution characteristics and source apportionment of heavy metal(loid)s in soil and groundwater of a retired industrial park

Heavy metal(loid)s(HMs)pollution has become a common and complex problem in industrial parks due to rapid industrialization and urbanization.Here,soil and groundwater were sampled from a retired industrial park to investigate the pollution characteristics of HMs.Results show that Ni,Pb,Cr,Zn,Cd,and Cu were the typical HMs in the soil.Source analysis with the positive matrix factorization model indicates that HMs in the topsoil stemmed from industrial activities,traffic emission,and natural source,and the groundwater HMs originated from industrial activities,groundwater-soil interaction,groundwater-rock interaction,and atmosphere deposition.The sequential extraction of soil HMs reveals that As and Hg were mainly distributed in the residue fraction,while Ni,Pb,Cr,Zn,Cd,and Cu mainly existed in the mobile fraction.Most HMs either in the total concentration or in the bioavailable fraction preferred to retain in soil as indicated by their high soil-water partitioning coefficients(K_(d)),and the K_(d) values were correlated with soil pH,groundwater redox potential,and dissolved oxygen.The relative stable soil-groundwater circumstance and the low active fraction contents limited the vertical migration of soil HMs and their release to groundwater.These findings increase our knowledge about HMs pollution characteristics of traditional industrial parks and provide a protocol for HMs pollution scrutinizing in large zones.

Paving the way toward soil safety and health:current status,challenges,and potential solutions

Soil is a non-renewable resource,providing a majority of the world’s food and fiber while serving as a vital carbon reservoir.However,the health of soil faces global threats from human activities,particularly widespread contamination by industrial chemicals.Existing physical,chemical,and biological remediation approaches encounter challenges in preserving soil structure and function throughout the remediation process,as well as addressing the complexities of soil contamination on a regional scale.Viable solutions encompass monitoring and simulating soil processes,with a focus on utilizing big data to bridge micro-scale and macro-scale processes.Additionally,reducing pollutant emissions to soil is paramount due to the significant challenges associated with removing contaminants once they have entered the soil,coupled with the high economic costs of remediation.Further,it is imperative to implement advanced remediation technologies,such as monitored natural attenuation,and embrace holistic soil management approaches that involve regulatory frameworks,soil health indicators,and soil safety monitoring platforms.Safeguarding the enduring health and resilience of soils necessitates a blend of interdisciplinary research,technological innovation,and collaborative initiatives.

Spatiotemporal variation of microeukaryotic biodiversity and biotic condition associated with disinfectants after the COVID-19 lockdown in Wuhan,China

Intensive application of chlorine-based disinfectants driven by the COVID-19 pandemic was suspected to be detrimental to receiving water ecosystems,but with little field evidence.We characterized the occurrences of typical disinfectants and microeukaryotic communities in surface waters associated with three wastewater treatment plants(WWTP)-river systems one year after the lockdown in Wuhan,China.Trihalomethanes(THMs)declined from summer 2020(0.01–1.82μg/L)to summer 2021(0.01–0.95μg/L),whereas quaternary ammonium salts(QAs)increased from summer 2020(0.53–6.35 ng/L)to summer 2021(8.49–191 ng/L).Biodiversity monitoring with environmental DNA(eDNA)revealed significant temporal variation in microeukaryotic community composition.The monitored disinfectants were correlated with some eukaryotic communities as demonstrated by redundancy analysis.For example,QAs were positively related to Cryptophyta relative abundance,but negatively related to Rotifera relative abundance.A microeukaryote-based multimetric index indicated ecological impairment near the Han River WWTP outlet in 2020.Our findings indicate the influence of heavily used disinfectants on river microeukaryotic communities,and the usefulness of assessing mid-term ecological risks from disinfectants in the post COVID-19 era.

Multimedia distribution and health risk assessment of typical organic pollutants in a retired industrial park

The overall cross-media risk evaluation of organic pollutants in retired industrial parks is insufficiently recognized.In this study,11 semi-volatile organic compounds(SVOCs)and 27 volatile organic compounds(VOCs)were measured in 531 soil and groundwater samples taken from a retired industrial park by coast in Zhejiang Province,China.Total petroleum hydrocarbons(TPHs),Di(2-ethylhexyl)phthalate(DEHP),benzene,and ethylbenzene were identified as the critical pollutants in the soil,while TPHs,1,2-dichloropropane(1,2-DCP),toluene,benzo[a]anthracene(BaA),and benzo[b]fluoranthene(BbF)were identified as critical pollutants in the groundwater for exceeding China national standards.The spatial correlation between the concentrations of organic pollutants in soil and groundwater was explored by employing the Geodetector model.Based on the results of spatial interpolation,high-risk hotspots regarding soil and groundwater pollution were identified.Moreover,the possible harm to human health of the critical pollutants were also under evaluation.Among various critical pollutants,benzene,ethylbenzene,and DEHP in soil,and 1,2-DCP in groundwater,were the main contributors to the overall health risk of multimedia pollution.This study developed a comprehensive approach to assess the risks posed by specific organic toxicants in various environmental media.The findings of this work can serve as a valuable reference for future management strategies in retired industrial parks.

Enhancing plant-microbe associated bioremediation of phenanthrene and pyrene contaminated soil by SDBS-Tween 80 mixed surfactants

The use of surfactants to enhance plant-microbe associated dissipation in soils contaminated with polycyclic aromatic hydrocarbons （PAHs） is a promising bioremediation technology. This comparative study was conducted on the effects of plant-microbe treatment on the removal of phenanthrene and pyrene from contaminated soil, in the presence of low concentration single anionic, nonionic and anionic-nonionic mixed surfactants. Sodium dodecyl benzene sulfonate （SDBS） and Tween 80 were chosen as representative anionic and nonionic surfactants, respectively. We found that mixed surfactants with concentrations less than 150 mg/kg were more effective in promoting plant-microbe associated bioremediation than the same amount of single surfactants. Only about （m/m） of mixed surfactants was needed to remove the same amount of phenanthrene and pyrene from either the planted or unplanted soils, when compared to Tween 80. Mixed surfactants （〈 150 mg/kg） better enhanced the degradation efficiency of phenanthrene and pyrene via microbe or plant-microbe routes in the soils. In the concentration range of 60-150 mg/kg, both ryegrass roots and shoots could accumulate 2-3 times the phenanthrene and pyrene with mixed surfactants than with Tween 80. These results may be explained by the lower sorption loss and reduced inteffacial tension of mixed surfactants relative to Tween 80, which enhanced the bioavailability of PAHs in soil and the microbial degradation efficiency. The higher remediation efficiency of low dosage SDBS-Tween 80 mixed surfactants thus advanced the technology of surfactant-enhanced plant-microbe associated bioremediation.

Removal of polycyclic aromatic hydrocarbons and phenols from coking wastewater by simultaneously synthesized organobentonite in a one-step process

The optimal condition for a one-step process removing organic compounds from coking wastewater by simultaneously synthesized organobentonite as a pretreatment was investigated.Results showed that sorption of organic compounds by organobentonite was positively correlated to the cation surfactant exchange on the bentonite and the octanol-water partition coefficient（Kow） of the solutes.With 0.75 g/L bentonite and 180 mg/L（60% of bentonite cation exchange capacity） cetyltrimethylammonium bromide,the removal efficiencies of the 16 polycyclic aromatic hydrocarbon（PAHs） specified by the US Environmental Protection Agency in coking wastewater except naphthalene were more than 90%,and that of benzo（a）pyrene was 99.5%.At the same time,the removal efficiencies of CODCr,NH3-N,volatile phenols,colour and turbidity were 28.6%,13.2%,8.9%,55% and 84.3%,respectively,and the ratio of BOD5/CODCr increased from 0.31 to 0.41.These results indicated that the one-step process had high removal efficiency for toxic and refractory hydrophobic organic compounds,and could improve the biodegradability of the coking wastewater.Therefore it could be a promising technology for the pretreatment of toxic and refractory organic wastewater.

Mitigation and remediation technologies for organic contaminated soils

Organic contaminated soils have become a widespread environmental problem,which may lead to a great threat to the quality of agricultural production and to human health.Physical,chemical,and biological technologies have been employed for the mitigation and remediation of organic contaminated soils.This paper reviews the progress of mitigation and remediation technologies for organic contaminated soils and suggests two different strategies for the mitigation of‘slightlycontaminated’agricultural soils and the remediation of‘heavily-contaminated’soils/sites,respectively.On this basis,directions for future research in this field are suggested.

Film mulching reduces antibiotic resistance genes in the phyllosphere of lettuce

Phyllosphere is an important reservoir of antibiotic resistance genes(ARGs),but the transfer mechanism of ARGs from soil and air to phyllosphere remains unclear.This study demonstrated that soil-air-phyllosphere was the dominant ARG transfer pathway,and blocking it by film mulching can reduce typical phyllosphere ARGs in lettuce by 80.7%-98.7%(89.5%on average).To further eliminate phyllosphere ARGs in lettuce grown with film mulching,the internal soil-endosphere-phyllosphere transfer pathway deserves more attention.We analyzed the ARG hosts and the resistome in lettuce rhizosphere and phyllosphere with film mulching via hybrid Illumina-Nanopore sequencing.Pseudomonas sp.7SR1 was more abundant than other ARG hosts,accounting for 1.0%and 47.1%of the total bacteria in rhizosphere and phyllosphere,respectively.The species has flagella that can promote mobility and can excrete extracellular polymeric substances and/or surfactant-like microbial products,which benefits its colonization in the phyllosphere.Impeding the migration of Pseudomonas sp.7SR1 via the soil-endosphere-phyllosphere pathway would be effective to further reduce ARGs in phyllosphere.Multidrug resistant genes were predominant in phyllosphere(40.3%of the total),and 87.6%of the phyllosphere ARGs were located on chromosomes,indicating relatively low horizontal gene transfer(HGT)potentials.This study provides insights into the transfer mechanism,hosts,and control strategies of phyllosphere ARGs in typical plants.

Utilizing surfactants to control the sorption,desorption, and biodegradation of phenanthrene in soil-water system

An integrative technology including the surfactant enhanced sorption and subsequentdesorption and biodegradation of phenanthrene in the soil-water system was introduced and tested. For slightly contaminated agricultural soils, cationic-nonionic mixed surfactant- enhanced sorption of organic contaminants onto soils could reduce their transfer to plants, therefore safe-guarding agricultural production. After planting, residual surfactants combined with added nonionic surfactant could also promote thedesorption and biodegradation of residual phenanthrene, thus providing a cost-effective pollution remediation technology.0ur results showed that the cationic-nonionic mixed surfactantsdodecylpyridinium bromide （DDPB） and Triton X-100 （TX100） significantly enhanced soil retention of phenanthrene. The maximum sorption coefficient Kd＊ of phenanthrene for contaminated soils treated by mixed surfactants was about24.5 times that of soils without surfactant （Kd ） and higher than the combined effects of DDPB and TX100 individually, which was about 16.7 and 1.5 times Kd , respectively.0n the other hand, TX100 could effectively remove phenanthrene from contaminated soils treated by mixed surfactants, improving the bioavailability of organic pollutants. Thedesorption rates of phenanthrene from these treated soils were greater than 85% with TX100 concentration above2000 mg/L and approached 100% with increasing TX100 concentration. The biodegradation rates of phenanthrene in the presence of surfactants reached over 95% in30days. The mixed surfactants promoted the biodegradation of phenanthrene to some extent in 10-22days, and had no obvious impact on phenanthrene biodegradation at the end of the experiment. Results obtained from this study provide some insight for the production of safe agricultural products and a remediation scheme for soils slightly contaminated with organic pollutants.

Formation and cytotoxicity of a new disinfection by-product (DBP) phenazine by chloramination of water containing diphenylamine

Disinfection by-products （DBPs） in drinking water have caused worldwide concern due to their potential carcinogenic effects. The formation of phenazine from diphenylamine （DPhA） chloramination was studied and its cytotoxicities for two human cancer cells were also investigated. Phenazine was detected synchronously with the consumption of DPhA by chloramination, which further confirmed that the new DBP phenazine can be produced along with N-nitrosodiphenylamine （NDPhA） from DPhA chloramination. The formation of phenazine had a maximum molar yield with solution pH increasing from 5.0 to 9.0, with phenazine as the main product for DPhA chloramination at lower pH, but higher pH favored the formation of NDPhA. Thus, solution pH is the key factor in controlling the formation of phenazine and NDPhA. Both the initial DPhA and chloramine concentrations did not show a significant effect on the molar yields of phenazine, although increasing the chloramine concentration could speed up the reaction rate of DPhA with chloramines. The cytotoxicity assays showed that phenazine had significant cell-specific toxicity towards T24 （bladder cancer cell lines） and HepG2 （hepatic tumor cell lines） cells with IC50 values of 0.50 and 2.04 mmol/L, respectively, and T24 cells being more sensitive to phenazine than HepG2 cells. The ICs0 values of phenazine, DPhA, and NDPhA for T24 cells were of the same order of magnitude and the cytotoxicity of phenazine for T24 cells was slightly lower than that of NDPhA （IC50, 0.16 mmol/L）, suggesting that phenazine in drinking water may have an adverse effect on human health.

Photosynthesis and related metabolic mechanism of promoted rice (Oryza sativa L.) growth by TiO2 nanoparticles

Titanium dioxide nanoparticle(nano-TiO2),as an excellent UV absorbent and photo-catalyst,has been widely applied in modem industry,thus inevitably discharged into environment.We proposed that nano-TiO2 in soil can promote crop yield through photosynthetic and metabolic disturbance,therefore,we investigated the effects of nano-TiO2 exposure on related physiologic-biochemical properties of rice(Oryza sativa L.).Results showed that rice biomass was increased>30%at every applied dosage(0.1-100 mg/L)of nano-TiO2.The actual photosynthetic rate(Y(II))significantly increased by 10.0%and 17.2%in the treatments of 10 and 100 mg/L respectively,indicating an increased energy production from photosynthesis.Besides,non-photochemical quenching(Y(NPQ))significantly decreased by 19.8%-26.0%of the control in all treatments respectively,representing a decline in heat dissipation.Detailed metabolism fingerprinting further revealed that a fortified transformation of monosaccharides(D-fructose,D-galactose,and D-talose)to disaccharides(D-cellobiose,and Dlactose)was accompanied with a weakened citric acid cycle,confirming the decrease of energy consumption in metabolism.All these results elucidated that nano-TiO2 promoted rice growth through the upregulation of energy storage in photosynthesis and the downregulation of energy consumption in metabolism.This study provides a mechanistic understanding of the stress-response hormesis of rice after exposure to nano-TiO2,and provides worthy information on the potential application and risk of nanomaterials in agricultural production.

“Waste”-ing away:Presence of Cu ions influences microbial degradation kinetics and metabolite formation of the prevalent brominated flame retardant BDE-47

Have you ever wondered what happened to that old cell phone you threw out last month?How about the 150 million other cell phones that were also disposed of in the past year?Although the world population has doubled in the past 50 years,global consumption of electronic devices has increased six fold(Belkhir and Elmeligi,2018)with nearly 45 million tonnes of electronic waste(e-waste)being produced in 2016 alone(Balde et al.,2017).That equates to 6.1 kg of e-waste per person across the globe and is equivalent in weight to over four thousand Eiffel towers(Balde et al.,2017)!

Adsorption characteristics of ciprofloxacin onto g-MoS2 coated biochar nanocomposites

The g-MoS2 coated biochar(g-MoS2-BC)composites were synthesized by coating original biochar with g-MoS2 nanosheets at 300℃(BC300)/700℃(BC700).The adsorption properties of the g-MoS2-BC composites for ciprofloxacin(CIP)were investigated with an aim to exploit its high efficiency toward soil amendment.The specific surface area and the pore structures of biochar coated g-MoS2 nanosheets were significantly increased.The g-MoS2-BC composites provided more n electrons,which was favorable in enhancing the n-n electron donor-acceptor(EDA)interactions between CIP and biochar.As a result,the g-MoS2-BC composites showed faster adsorption rate and greater adsorption capacity for CIP than the original biochar.The coated g-MoS2 nanosheets contributed more to CIP adsorption on the g-MoS2-BC composites due to their greater CIP adsorption capacity than the original biochar.Moreover,the synergistic effect was observed for CIP adsorption on g-MoS2-BC700,and suppression effect on g-MoS2-BC300.In addition,the adsorption of CIP onto g-MoS2-BC composites also exhibited strong dependence on the solution pH,since it can affect both the adsorbent surface charge and the speciation of contaminants.It was reasonably suggested that the mechanisms of CIP adsoiption on g-MoS2-BC composites involved pore-filling effects,k-k EDA interaction,electrostatic interaction,and ion exchange interaction.These results are useful for the modification of biochar in exploiting the novel amendment for contaminated soils.

Tricrystalline TiO_2 with enhanced photocatalytic activity and durability for removing volatile organic compounds from indoor air

It is important to develop efficient and economic techniques for removing volatile organic compounds（VOCs） in indoor air. Heterogeneous Ti O2-based semiconductors are a promising technology for achieving this goal. Anatase/brookite/rutile tricrystalline Ti O2 with mesoporous structure was synthesized by a low-temperature hydrothermal route in the presence of HNO3.The obtained samples were characterized by X-ray diffraction and N2 adsorption-desorption isotherm. The photocatalytic activity was evaluated by photocatalytic decomposition of toluene in air under UV light illumination. The results show that tricrystalline Ti O2 exhibited higher photocatalytic activity and durability toward gaseous toluene than bicrystalline Ti O2,due to the synergistic effects of high surface area, uniform mesoporous structure and junctions among mixed phases. The tricrystalline Ti O2 prepared at R HNO3= 0.8, containing80.7% anatase, 15.6% brookite and 3.7% rutile, exhibited the highest photocatalytic activity,about 3.85-fold higher than that of P25. The high activity did not significantly degrade even after five reuse cycles. In conclusion, it is expected that our study regarding gas-phase degradation of toluene over tricrystalline Ti O2 will enrich the chemistry of the Ti O2-based materials as photocatalysts for environmental remediation and stimulate further research interest on this intriguing topic.

Sorption of phenanthrene to biochar modified by base

Biochar （BC） is a potential material for removal of polycyclic aromatic hydrocarbons t^om soil and water, and base modification is a promising method for improving its sorption ability. In this study, we synthesized a series of base-modified biochars, and evaluated their sorption of phenanthrene. Original biochars were produced by pyrolysis of three feedstocks （rice straw, wood and bamboo） at five temperatures （300~C, 350~C, 400~C, 500~C and 700~C）. Base-modified biochars were further obtained by washing ofbiochars with base solution. The base soluble carbon （SC） was extracted from the supernatant, which were only obtained from biochars pyrolyzed at low temperatures （ 〈 500~C） and the content was decreased with the increase of pyrolysis temperature. The SC content between different feedstocks followed the trend office straw〉wood〉bamboo when same pyrolysis conditions were applied, It was tbund that base modification improved the sorption of phenanthrene on biochars that SC could be extracted from （extractable-BCs）. However, base treatment but had limited effects for biochars that no SC could be extracted from. It suggested that base modification improved the sorption of phenanthrene to extractable-BCs by removing the SC and thus increasing the surface area and hydrophobicity. Therefore, base modification was suggested to be used in modifying extractable-BCs.

Effect of surfactant on phenanthrene metabolic kinetics by Citrobacter sp. SA01

To attain a better understanding of the effects of surfactants on the metabolic kinetics of hydrophobic organic compounds, the biodegradation of phenanthrene by Citrobacter sp. SA01 was investigated in a batch experiment containing Tween 80, sodium dodecyl benzene sulfonate and liquid mineral salt medium. The Monod model was modified to effectively describe the partition, phenanthrene biodegradation and biopolymer production. The results showed that Tween 80 and sodium dodecyl benzene sulfonate （each at 50 rag/L） enhanced phenanthrene metabolism and poly-β-hydroxybutyrate production as indicated by the increasing amounts of intermediates Coy 17.2% to 47.9%）, and percentages of poly-β- hydroxybutyrate （by 107.3% and 33.1%） within the cell dry weight when compared to their absence. The modified Monod model was capable of predicting microbial growth, phenanthrene depletion and biopolymer production. Furthermore, the Monod kinetic coefficients were largely determined by the surfactant-enhanced partition, suggesting that partitioning is a critical process in surfactant-enhanced bioremediation of hydro- phobic organic compounds.

Effect of central ventilation and air conditioner system on the concentration and health risk from airborne polycyclic aromatic hydrocarbons

Central ventilation and air conditioner systems are widely utilized nowadays in public places for air exchange and temperature control,which significantly influences the transfer of pollutants between indoors and outdoors.To study the effect of central ventilation and air conditioner systems on the concentration and health risk from airborne pollutants,a spatial and temporal survey was carried out using polycyclic aromatic hydrocarbons （PAHs） as agent pollutants.During the period when the central ventilation system operated without air conditioning （AC-off period）,concentrations of 2-4 ring PAHs in the model supermarket were dominated by outdoor levels,due to the good linearity between indoor air and outdoor air （rp〉0.769,p〈0.05）,and the slopes （1.2-4.54） indicated that ventilating like the model supermarket increased the potential health risks from low molecular weight PAHs.During the period when the central ventilation and air conditioner systems were working simultaneously （AC-on period）,although the total levels of PAHs were increased,the concentrations and percentage of the particulate PAHs indoors declined significantly.The BaP equivalency （BaPeq） concentration indicated that utilization of air conditioning reduced the health risks from PAHs in the model supermarket.

Acid-assisted hydrothermal synthesis of nanocrystalline TiO_2 from titanate nanotubes: Influence of acids on the photodegradation of gaseous toluene

In order to efficiently remove volatile organic compounds（VOCs） from indoor air, onedimensional titanate nanotubes（Ti NTs） were hydrothermally treated to prepare TiO2 nanocrystals with different crystalline phases, shapes and sizes. The influences of various acids such as CH3 COOH, HNO3, HCl, HF and H2SO4 used in the treatment were separately compared to optimize the performance of the TiO2 nanocrystals. Compared with the strong and corrosive inorganic acids, CH3COOH was not only safer and more environmentally friendly, but also more efficient in promoting the photocatalytic activity of the obtained TiO2. It was observed that the anatase TiO2 synthesized in 15 mol/L CH3COOH solution exhibited the highest photodegradation rate of gaseous toluene（94%）, exceeding that of P25（44%） by a factor of more than two. The improved photocatalytic activity was attributed to the small crystallite size and surface modification by CH3COOH. The influence of relative humidity（20%–80%） on the performance of TiO2 nanocrystals was also studied. The anatase TiO2 synthesized in 15 mol/L CH3COOH solution was more tolerant to moisture than the other TiO2 nanocrystals and P25.