Organophosphate esters(OPEs)are increasingly recognized as pervasive environmental contaminants,primarily from their extensive application in flame retardants and plasticizers.Despite their widespread presence,the intricacies of OPE bioaccumulation within aquatic ecosystems remain poorly understood,particularly the environmental determinants influencing their distribution and the bioaccumulation dynamics across aquatic food chains.Here we show that water temperature plays a crucial role in modulating the dispersion of OPE in the aquatic environment of Poyang Lake.We quantified OPE concentrations across various matrices,uncovering levels ranging from 0.198 to 912.622 ng L^(-1) in water,0.013e493.36 ng per g dry weight(dw)in sediment,0.026e41.92 ng per g wet weight(ww)in plankton,0.13e2100.72 ng per g dw in benthic invertebrates,and 0.31e3956.49 ng per g dw in wild fish,highlighting a pronounced bioaccumulation gradient.Notably,the intestines emerged as the principal site for OPE absorption,displaying the highest concentrations among the seven tissues examined.Among the various OPEs,tris(chloroethyl)phosphate was distinguished by its significant bioaccumulation potential within the aquatic food web,suggesting a need for heightened scrutiny.The propensity for OPE accumulation was markedly higher in benthic invertebrates than wild fish,indicating a differential vulnerability within aquatic biota.This study lays a foundational basis for the risk assessment of OPEs as emerging contaminants and underscores the imperative to prioritize the examination of bioaccumulation effects,particularly in benthic invertebrates,to inform future environmental safeguarding strategies.
Zhenfei YanChenglian FengYiping XuJindong WangNannan HuangXiaowei JinFengchang WuYingchen Bai
The self-heating lunch box(SHLB)is a kind of popular instant food in China,yet little is known about the associated chemical release risk during its heating process.In this study,we investigated organophosphate esters(OPEs)in original unheated food(UF),SHLB-heated processed food(HF)and potential OPE release from SHLB packaging materials.Significantly higher concentrations of OPEs were observed in HF(267±246 ng/g dry weight(dw))than in UF(163±211 ng/g dw)(p<0.001),suggesting an introduction of additional OPEs during heating processes.Tris(2-chloroethyl)phosphate,triethyl phosphate,and tris(2-chloroisopropyl)phosphate exhibited the highest absolute increased amounts,with 137,48.8,and 149%growth in HF than in UF,respectively.Migration testing revealed that packaging materials were rich in OPEs and can release considerable OPEs into food simulates(range,14.7-90.8 ng/g;mean,47.9±21.8).Influencing factors(temperature,contact time,oily food)on OPE migration from packaging materials to food were assessed.Higher temperature and longer contact time increased OPE contents in food simulates.Moreover,the presence of abundant OPEs in UF and significant correlations among different OPEs(p<0.05)suggested contamination happened during food processing and storage.With one SHLB meal a day,a 12-fold increase of OPE intake was observed for humans compared to those following a traditional dietary habit.In the high-exposure(95th percentile)scenario,hazard quotients of nine OPEs ranged from 0.00005 to 0.05.Our results suggested that the SHLB exposure pathway of OPEs should be particularly paid attention to in specific subpopulations that prefer this dietary habit.
Xiaomin LiYuhan YinWei ZhouHongting LiBoyuan HuYajing CuiRuoxian ZhouPeilong WangJianjie Fu
Eleven organophosphate esters(OPEs)in the air and seawater were investigated from the northwestern Pacific Ocean to the Southern Ocean during the 2018 Chinese 34th Antarctic Scientific Expedition.The concentration of total OPEs ranged from 164.82 to 3501.79 pg/m~3in air and from 4.54 to 70.09 ng/L in seawater.Two halogenated OPEs,tri(chloropropyl)phosphate(TCPP)and tri(2-chloroethyl)phosphate(TCEP),were generally more abundant than the non-halogenated OPEs.A levelⅢfugacity model was developed to simulate the transfer and fate of seven OPEs in the air and seawater regions of the central Ross Sea.The model results indicate that OPEs are transferred from the air to the seawater in the central Ross Sea in summer,during which the Ross Sea acts as a final OPE sink.Dry and wet deposition dominated the processes involving OPE transfer to seawater.The OPE degradation process was also found to be more pervasive in the atmosphere than in the seawater region.These findings highlights the importance of long-range transport of OPEs and their air–seawater interface behavior in the Antarctic.
Organophosphate esters(OPEs)are used primarily as flame-retardants and plasticizers.OPEs are commonly detected in various environmental matrices,food and drinking water,and their metabolites are frequently found and quantified in urine.Potential adverse impacts on human health,including carcinogenicity,neurotoxicity,developmental and reproductive toxicity have been well documented.Urinary concentration of OPE metabolites can vary in the same individual,depending on the sampling time,thus introducing significant uncertainty in exposure assessment.The current study focusses on the assessment of short term temporal variability in adult men and women residing in Canada's Capital Region.Fifteen OPE metabolites were analyzed in 562 daily urine samples,collected every three days for five weeks from 11 volunteers.Sample extraction procedure was performed on an automated SPE and extracts analyzed using UPLC-MS/MS.In spot urine samples as well as first morning void(FMV),the detection frequency was greater than 50%for bis(2-chloroethyl)hydrogen phosphate(BCEP),bis(1-chloro-2-propyl)phosphate(BCIPP),bis(1,3-dichloro-2-propyl)phosphate(BDCIPP),diphenyl phosphate(DPHP)and bis(2,4-ditert-butylphenyl)hydrogen phosphate(B2,4DtBPP).Significant difference was observed in males and females for BCEP and BCIPP.Intra-class correlation coefficient(ICC)for creatinine corrected data for the spot urine samples ranged from 0.37 to 0.69.Good reproducibility was observed for creatinine corrected DPHP and BCIPP in both spot urine and FMV samples.More variation was observed between study participants in the spot urine samples when compared to the FMV samples.However,when considering diurnal difference there was a considerable inter-day variation in the FMV samples compared to the spot samples.The strength of the study is that the participants belonged to the same geographical location and working in the same facility,hence spatial variability did not influence the outcome of the results.
In recent years,neonicotinoids(NEOs)and organophosphate esters(OPEs)have been widely used as substitutes for traditional pesticides and brominated fame-retardants,respectively.Previous studies have shown that those compounds can be frequently detected in environmental and human samples,are able to penetrate the placental barrier,and are toxic to animals.Thus,it is reasonable to speculate that NEOs and OPEs may have potential adverse effects in humans,especially during development.We employed a human embryonic stem cell differentiation-and liver S9 fraction metabolism-based fast screening model to assess the potential embryonic toxicity of those two types of chemicals.We show that four NEO and five OPE prototypes targeted mostly ectoderm specification,as neural ectoderm and neural crest genes were down-regulated,and surface ectoderm and placode markers up-regulated.Human liver S9 fraction's treatment could generally reduce the effects of the chemicals,except in a few specific instances,indicating the liver may detoxify NEOs and OPEs.Our findings suggest that NEOs and OPEs interfere with human early embryonic development.
When organophosphate pesticides(OPs)are not used and handled in accordance with the current rules and standards,it results in serious threats to the aquatic environment and human health.Phaeodactylum tricornutum is a prospective microalgae-based system for pollutant removal and carbon sequestration.Genetically engineered P.tricornutum,designated as the OE line(endogenously expressing purple acid phosphatase 1[PAP1]),can utilize organic phosphorus for cellular metabolism.However,the competencies and mechanisms of the microalgae-based system(namely the OE line of P.tricornutum)for metabolizing OPs remain to be addressed.In this study,the OE line exhibited the effective biodegradation competencies of 72.12%and 68.2%for 30 mg L^(-1)of dichlorvos and 50 mg L^(-1)of glyphosate,accompanied by synergistic accumulations of biomass(0.91 and 0.95 g L^(-1))and lipids(32.71%and 32.08%),respectively.Furthermore,the biodiesel properties of the lipids from the OE line manifested a high potential as an alternative feedstock for microalgae-based biofuel production.A plausible mechanism of OPs biodegraded by overexpressed PAP1 is that sufficient inorganic P for adenosine triphosphate and concurrent carbon flux for the reduced form of nicotinamide adenine dinucleotide phosphate biosynthesis,which improved the OP tolerance and biodegradation competencies by regulating the antioxidant system,delaying programmed cell death and accumulating lipids via the upregulation of related genes.To sum up,this study demonstrates a potential strategy using a genetically engineered strain of P.tricornutum to remove high concentrations of OPs with the simultaneous production of biomass and biofuels,which might provide novel insights for microalgae-based pollutant biodegradation.
Xiang WangGuo-Hui HeZhen-Yao WangHui-Ying XuJin-Hua MouZi-Hao QinCarol Sze Ki LinWei-Dong YangYalei ZhangHong-Ye Li
