RESUMO
We elucidate the application of L3-edge X-ray absorption near edge structure (XANES) spectra to the local structural analysis of lanthanoids in aqueous solution, iron hydroxide, manganese dioxide, and calcium carbonate. The L3-edge XANES spectra of lanthanoid compounds showed sharp white lines. The full width at half-maximum (FWHM) values of lanthanoid aqua ions exhibited a convex tetrad curve in the series variation across the lanthanoid series. The variation is attributable to 4f electron orbitals and can be explained by the refined spin-pairing energy theory. For each lanthanoid, the FWHM values of lanthanoid compounds roughly decreased with increasing local coordination numbers. However, they did not faithfully reflect the local coordination sphere of the lanthanoid complex having a high and distorted coordination sphere and were rather sensitive to their chemical forms. The relationship between the magnitude of the FWHM values was determined by the crystal field splitting or degeneracy of 5d orbitals. The systematic variation of FWHM can be explained by the ligand strength of the ligand molecules (-H2O0, -O-, -OH-, -CO32-, -Cl-, and -O2-) that cause the crystal field splitting. Therefore, the FWHM values of L3-edge XANES of lanthanoid compounds may be more useful in speciation analysis rather than structural analysis.
RESUMO
A 4-month-old breast-fed girl presented with poor weight gain, and had edema and repeated erythema from 5 months of age. The diagnosis of protein-losing enteropathy (PLE) was confirmed on 99m Tc-labeled human serum albumin scintigraphy. Specific IgE radioallergosorbent test was class 3 for egg white, class 2 for egg yolk, and negative for other foods. Elimination of egg from the mother's diet and oral epinastine hydrochloride treatment and sodium cromolyn improved hypoalbuminemia, hypogammaglobulinemia, and erythema. PLE and erythema coincident in a breast-fed infant suggests that IgE-mediated allergy may play a leading role in some cases of PLE due to food allergy in infants.
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Sludge ozonation is a promising technology for dealing with the increasing challenge of excess sludge treatment and disposal. However, nitrogen behavior during sludge ozonation and subsequent biological removal remains unclear. To clarify the feasibility and stability of oxidizing organic nitrogen (released during sludge ozonation) in the bioreactor (but not during ozonation), and the best operational conditions for sludge ozonation, nitrogen behavior was investigated by a long-term observation. The results showed that when inlet ozone concentration increased from 30 to 80 mg O3/L, and ozonation time decreased from 29 to 11 h, less soluble organic nitrogen was oxidized to ammonia (from 66.1 to 18.7% of soluble total nitrogen). This can reduce the operational costs of sludge ozonation. Furthermore, it is feasible to convert organic nitrogen to nitrate by biological processes because full nitrification was restored in three weeks after shock loading of organic nitrogen owing to the change in ozonation conditions. After combining sludge ozonation with the anaerobic/oxic process, the mass balance for nitrogen showed that nitrogen in the excess sludge decreased with increasing sludge reduction rate. The decreased nitrogen in the excess sludge was mainly transformed to nitrogen gas by denitrification, whereas nitrogen in the effluent did not increase noticeably.
Assuntos
Nitrogênio/química , Ozônio , Esgotos , Poluentes Químicos da Água/química , Reatores Biológicos , Monitoramento Ambiental , Projetos Piloto , Fatores de TempoRESUMO
Field surveys on persistent organic pollutant (POP) bioaccumulation were conducted with oysters, clams and scallops whose consumption amount accounted for large shares in the total consumption of shellfish in Japan. There was no numerical difference in bioaccumulation characteristics between oysters, clams, scallops, Corbicula and Mytilus galloprovincialis. Therefore, it was clear that the bioaccumulation characteristics in oysters, clams and scallops, which are important for food, could be ascertained by using the monitoring results with Corbicula and M. galloprovincialis which are easily sampled in various water areas in the world. Non-cancer risk (hazard quotient, HQ) and cancer risk (excess cancer risk, ΔR) via shellfish ranged from 10â»8 to 10â»4 and from 10⻹¹ to 10â»7, respectively, at sampling points, which showed the risks of POP exposure via shellfish to be low enough. However, concerning the intake of other food, the importance of dieldrin monitoring should be suggested in Japan. Based on these results, the effectiveness of primary risk assessment could be suggested for screening chemicals whose preferential monitoring is needed.
Assuntos
Bivalves/metabolismo , Monitoramento Ambiental , Poluentes Ambientais/análise , Compostos Orgânicos/análise , Animais , Baías , Peso Corporal , Geografia , Sedimentos Geológicos/química , Ilhas , Japão , Mytilus/metabolismo , Neoplasias/epidemiologia , Medição de Risco , Frutos do Mar , Qualidade da ÁguaRESUMO
Two series of two-phase anaerobic systems, consisting of a hyperthermophilic (80°C) reactor and a thermophilic (55°C) reactor, fed with a mixture of kitchen garbage (KG) and polylactide (PLA), was compared with a single-phase thermophilic reactor for the overall performance. The result indicated that ammonia addition under hyperthermophilic condition promoted the transformation of PLA particles to lactic acid. The systems with hyperthermophilic treatment had advantages on PLA transformation and methane conversion ratio to the control system. Under the organic loading rate (OLR) of 10.3 g COD/(L day), the PLA transformation ratios of the two-phase systems were 82.0% and 85.2%, respectively, higher than that of the control system (63.5%). The methane conversion ratios of the two-phase systems were 82.9% and 80.8%, respectively, higher than 70.1% of the control system. The microbial community analysis indicated that hyperthermophilic treatment is easily installed to traditional thermophilic anaerobic digestion plants without inoculation of special bacteria.
Assuntos
Recuperação e Remediação Ambiental/métodos , Resíduos de Alimentos , Poliésteres/metabolismo , Temperatura , Amônia/farmacologia , Anaerobiose , Bactérias/metabolismo , Análise da Demanda Biológica de Oxigênio , Reatores Biológicos/microbiologia , Hidrólise , Metano/biossíntese , Esgotos/microbiologia , ÁguaRESUMO
The objective of this study was to evaluate the promotion effect of ammonia on the biodegradation of polylactide (PLA) under hyperthermophilic (80°C) and thermophilic (55°C) anaerobic condition. The results showed that PLA was transformed to lactic acid under hyperthermophilic conditions, but that the transformation ratio was negligible under thermophilic conditions. The hydrolysis process can be markedly increased with ammonia addition and microorganism activity. The maximum transformation ratios of the two kinds of PLA used in this study were 65.2% and 51.8%, respectively, with ammonia addition of 4 g N/L over 3 days treatment of anaerobic sludge. After the hyperthermophilic pretreatment, the hydrolysis products were converted to methane by methanogens under the thermophilic and anaerobic conditions. The final methane conversion ratios of the two kinds of PLA after 22 days treatment were 81.8% and 77.0%, respectively.
Assuntos
Amônia/farmacologia , Poliésteres/metabolismo , Temperatura , Anaerobiose/efeitos dos fármacos , Biodegradação Ambiental/efeitos dos fármacos , Análise da Demanda Biológica de Oxigênio , Ácidos Carboxílicos/análise , Fermentação/efeitos dos fármacos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Hidrólise/efeitos dos fármacos , Cinética , Metano/análise , Fatores de TempoRESUMO
The behavior of inorganic elements (including phosphorus, nitrogen, and metals) during sludge ozonation was investigated using batch tests and the effects of metals on sludge solubilization were elucidated. A decrease of â¼ 50% in the ratio of sludge solubilization was found to relate to a high iron content 80-120 mgFe/gSS than that of 4.7-7.4 mgFe/gSS. During sludge ozonation, the pH decreased from 7 to 5, which resulted in the dissolution of chemically precipitated metals and phosphorus. Based on experimental results and thermodynamic calculation, phosphate precipitated by iron and aluminum was more difficult to release while that by calcium released with decrease in pH. The release of barium, manganese, and chrome did not exceed 10% and was much lower than COD solubilization; however, that of nickel, copper, and zinc was similar to COD solubilization. The ratio of nitrogen solubilization was 1.2 times higher than that of COD solubilization (R(2)=0.85). Of the total nitrogen solubilized, 80% was organic nitrogen. Because of their high accumulation potential and negative effect on sludge solubilization, high levels of iron and aluminum in both sewage and sludge should be considered carefully for the application of the advanced sewage treatment process with sludge ozonation and phosphorus crystallization.
Assuntos
Compostos Inorgânicos/química , Ozônio/química , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Algoritmos , Bário/química , Cobre/química , Concentração de Íons de Hidrogênio , Ferro/química , Manganês/química , Metais/química , Níquel/química , Nitrogênio/química , Fósforo/química , Solubilidade , Termodinâmica , Zinco/químicaRESUMO
Chlorophyll-a concentration has been used as an indicator to estimate microcystin levels in water bodies. This study examined the microcystin to chlorophyll-a ratio in a fishpond in Japan. The ratio varied spatially and temporally during the six-month field survey, which is consistent with reports by other researchers. We investigated the causes of the variability of the ratio by quantifying microcystin synthetase (mcy) A gene with real-time PCR, so as to observe the growth of microcystin-producing cyanobacteria and Microcystis strains in natural cyanobacterial blooms. The application of real-time PCR enabled corroboration of the relationship between the toxigenicity and the toxicity of the blooms. The microcystin to chlorophyll-a ratio was influenced by the combined effects of the durability of the toxic bloom, and the quantity of microcystin-producing cyanobacteria carrying the mcy A gene, especially toxic Microcystis strains. Cyanobacterial blooms produced more microcystin when high concentrations of microcystin-producing Microcystis aggregated in a stationary state with low growth rates. The variable toxicity of blooms needs to be reflected in accurate and efficient alert systems for toxic cyanobacteria and cyanotoxins.
Assuntos
Clorofila/análise , Cianobactérias/crescimento & desenvolvimento , Água Doce/química , Microcistinas/análise , Poluentes Químicos da Água/análise , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Clorofila A , Cianobactérias/genética , Cianobactérias/metabolismo , Monitoramento Ambiental/métodos , Eutrofização , Água Doce/microbiologia , Japão , Microcistinas/toxicidade , Peptídeo Sintases/genética , Peptídeo Sintases/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Poluentes Químicos da Água/toxicidadeRESUMO
The applicability of Corbicula as a bioindicator for monitoring organochlorine pesticides (OCPs) in fresh and brackish waters is presented here. Differences in isomer compositions and OCP bioaccumulation levels were analyzed in western Japan and the Pearl River Delta (PRD) in China. Isomer compositions of DDTs, chlordanes, and HCHs were significantly different between the two areas because of their different historical uses and property of the chemicals. This is represented by the (DDE + DDD)/DDT ratio in Corbicula, ranging 4.9-39 in western Japan and 1.1-2.4 in the PRD. However, isomer compositions in Corbicula reflected those in water, and the different patterns in Corbicula likely reflected the usage history. Concentrations of dissolved oxygen, suspended solids, and volatile suspended solids in water, and the difference in species did not influence OCP bioaccumulative levels in Corbicula when conducting biomonitoring. These levels are likely similar to those in Mytilus galloprovincialis. Therefore, Corbicula could be an appropriate bioindicator for monitoring OCPs in fresh and brackish waters.
Assuntos
Corbicula/metabolismo , Monitoramento Ambiental/métodos , Água Doce/química , Hidrocarbonetos Clorados/metabolismo , Praguicidas/metabolismo , Água do Mar/química , Poluentes Químicos da Água/metabolismo , Animais , DDT/análise , DDT/metabolismo , Sedimentos Geológicos/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Poluentes Químicos da Água/análiseRESUMO
The occurrence of nine different types of pharmaceuticals and caffeine were analyzed in various units of three wastewater treatment plants (WWTPs) and their receiving rivers in Beijing, China. Analyte concentrations were determined using ultra performance liquid chromatograph-tandem quadruple mass spectrometers (UPLC-MS/MS) and multiple-reaction monitoring. The studied pharmaceuticals and caffeine were found in all the WWTPs and receiving rivers. Their concentrations in the WWTP influents varied from 38 ng/L of sulpiride to 89.5 microg/L of caffeine, and those in the effluents ranged from 27 ng/L of sulpiride to 2.7 microg/L of erythromycin. Typically, the biological treatment appeared more effective in the removal of pharmaceuticals and caffeine than primary treatment in a WWTP. For an individual compound, the overall removal efficiency varied from one WWTP to the next. Mean values ranged from no removal of carbamazepine to 99.8% removal of caffeine. Most of the compounds in the receiving rivers were present at similar or higher concentrations compared to those in the WWTP effluents. The data set for this study does not include variations in concentrations along receiving waters because there were other point and nonpoint sources discharging to these rivers. The preliminary aquatic environmental risk assessment showed that carbamazepine, erythromycin, and trimethoprim is a potential chronic environmental risk in water bodies in Beijing, China, and is worth further investigation.
Assuntos
Cafeína/química , Preparações Farmacêuticas/química , Rios/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , China , Monitoramento AmbientalRESUMO
The occurrence and elimination of 19 micro-organic pollutants including endocrine disrupting chemicals (EDCs) and pharmaceuticals and personal care products (PPCPs) in a full-scale anaerobic/anoxic/aerobic-membrane bioreactor process was investigated. The investigated process achieved over 70% removal of the target EDCs and 50%-100% removal of most of the PPCPs, with influent concentration ranging from ng/L to µg/L. Three PPCPs, carbamazepine, diclofenac and sulpiride were not well removed, with the removal efficiency below 20%. A rough mass balance suggests that the targets were eliminated through sludge-adsorption and/or biodegradation, the former of which was particularly significant for the removal of hydrophobic compounds. The two-phase fate model was employed to describe the kinetics of sludge-adsorption and biodegradation. It was found that the fast sludge adsorption (indicated by mass-transfer rates greater than 10 for most compounds) is responsible for the rapid decline of the aqueous concentration of the targets in the first compartment of the treatment process (i.e. in the anaerobic tank). In contrast, the slow biodegradation proved to be the rate-determining step for the entire degradation process, and the rates are generally positively related to the dissolved oxygen level. On the other hand, this study showed that the removal rates of most targets can reach a quasi-plateau in 5 h under aerobic conditions, indicating that hydraulic retention time of ca. 5 h in aerobic tanks should be sufficient for the elimination of most targets.
Assuntos
Reatores Biológicos , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Purificação da Água/métodos , Aerobiose , AnaerobioseRESUMO
Chloride in fly ash from municipal solid waste incinerators (MSWIs) is one of the obstructive substances in recycling fly ash as building materials. As a result, we have to understand the behavior of chlorides in recycling process, such as washing. In this study, we used X-ray absorption near edge structure (XANES) and X-ray diffraction (XRD) to study the chloride behavior in washed residue of raw fly ash (RFA). We found that a combination of XRD and XANES, which is to use XRD to identify the situation of some compounds first and then process XANES data, was an effective way to explain the chlorides behavior in washing process. Approximately 15% of the chlorine in RFA was in the form of NaCl, 10% was in the form of KCl, 51% was CaCl(2), and the remainder was in the form of Friedel's salt. In washing experiments not only the mole percentage but also the amount of soluble chlorides including NaCl, KCl and CaCl(2) decreases quickly with the increase of liquid to solid (L/S) ratio or washing frequency. However, those of insoluble chlorides decrease slower. Moreover, Friedel's salt and its related compound (11CaO.7Al(2)O(3).CaCl(2)) were reliable standards for the insoluble chlorides in RFA, which are strongly related to CaCl(2). Washing of RFA promoted the release of insoluble chlorides, most of which were in the form of CaCl(2).
Assuntos
Carbono/química , Cloretos/química , Material Particulado/química , Eliminação de Resíduos , Cinza de Carvão , Incineração , Modelos Lineares , Padrões de Referência , Difração de Raios XRESUMO
Occurrence and fate of eight kinds of selected endocrine-disrupting compounds (EDCs) in three sewage treatment plants (STPs) of Beijing, China was investigated. These EDCs, composed of 4-octylphenol (4-OP), 4-n-nonylphenol (4-n-NP), bisphenol A (BPA), estrone (E1), 17alpha-estradiol (17alpha-E2), 17beta-estradiol (E2), estriol (E3) and 17alpha-ethinylestradiol (EE2), in every step of STPs, were simultaneously analysed by gas chromatography/mass spectrometry after derivatisation. All the EDCs were detected in the influents of three STPs, and BPA was the most abundant compound. The concentrations of EDCs ranged from 36.6 ng/l of 17alpha-E2 (STP C) to 1342.3 ng/l of BPA (STP B) in the influent sewages and from below limits of detection of E2 and E3 (STP C) to 142.5 ng/l of E1 (STP B) in the effluent sewages. The STPs could not remove alkylphenols effectively from the aqueous phase with less than 40% reduction. BPA decreased over 90%, and steroid estrogens achieved considerable reductions from 64.8% of E2 to 94.9% of E3. Generally, biological treatment was more effective in removing alkylphenols, BPA and natural estrogens from the aqueous phase than primary treatment. However, the synthetic estrogen, EE2, was mostly removed by the primary treatment with about 63.5% reduction. It is the first time that the concentration of 17alpha-E2 in the sewage of China was reported in this paper. The compound might have a bearing with the waste effluents of dairy farms around urban area of Beijing.
Assuntos
Disruptores Endócrinos/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Compostos Benzidrílicos , China , Disruptores Endócrinos/química , Estradiol/análise , Estradiol/química , Estrona/análise , Estrona/química , Estrutura Molecular , Fenóis/análise , Fenóis/química , Poluentes Químicos da Água/análiseRESUMO
For co-digestion of waste activated sludge with kitchen garbage, hyperthermophilic digester systems that consisted of an acidogenic reactor operated at hyperthermophilic (70 degrees C) and a methanogenic reactor operated at mesophilic (35 degrees C), thermophilic (55 degrees C) or hyperthermophilic (65 degrees C) conditions in series were studied by comparing with a thermophilic digester system that consisted of thermophilic (55 degrees C) acidogenic and methanogenic reactors. Laboratory scale reactors were operated continuously fed with a substrate blend composed of concentrated waste activated sludge and artificial kitchen garbage. At the acidogenic reactor, solubilization efficiencies of chemical oxygen demand (COD), carbohydrate and protein at 70 degrees C were about 39%, 42% and 54%, respectively, and they were higher than those at 55 degrees C by around 10%. The system of acidogenesis at 70 degrees C and methanogenesis at 55 degrees C was stable and well-functioned in terms of treatment performances and low ammonium nitrogen concentrations. Microbial community analysis was conducted using a molecular biological method. The key microbe determined at the hyperthermophilic acidogenesis step was Coprothermobacter sp., which was possibly concerned with the degradation of protein in waste activated sludge. The present study proved that the hyperthermophilic system was advantageous for treating substrate blends containing high concentrations of waste activated sludge.
Assuntos
Bactérias Anaeróbias/metabolismo , Reatores Biológicos/microbiologia , Microbiologia de Alimentos , Resíduos de Alimentos , Eliminação de Resíduos/métodos , Esgotos/microbiologia , Biodegradação Ambiental , Temperatura AltaRESUMO
Microcystins are produced by cyanobacteria carrying microcystin synthetase (mcy) genes in blooms. The present study investigated seasonal variations in concentrations of mcy A and 16S rRNA genes, encoded in the genus Microcystis using real-time PCR, and measured the water quality variables and microcystin concentrations in a hypereutrophic fish pond between June and November 2007. Prior to field survey, the relationship between axenic Microcystis aeruginosa NIES 102 cell abundance and concentrations of mcy A and 16S rRNA genes was determined by real-time PCR in the laboratory. Based on the quantitative relationship, microcystin-producing and total Microcystis cell numbers in the study site were estimated. The average dominance ratio of microcystin-producing strains in the total Microcystis population was approximately 80% and microcystin concentration was highly associated with toxic Microcystis cell numbers equivalent of mcy A gene. It was also observed that total nitrogen concentration was associated with development of Microcystis blooms, and high concentrations of NOx and NH4 increased microcystin production by promoting growth of microcystin-producing Microcystis strains.
Assuntos
Microcystis/crescimento & desenvolvimento , Sequência de Bases , Primers do DNA , Microcistinas/análise , Microcistinas/toxicidade , Microcystis/genética , Microcystis/metabolismo , Reação em Cadeia da PolimeraseRESUMO
To efficiently reduce and reuse fly ash from incinerators, we suggest trying a new alkaline reagent to neutralize the acid compounds in discharged gas from incinerators and reuse fly ash as the raw material in the cement industry. Normally the washing process includes a pretreatment method to remove chlorides to comply with the strict standards for cement. We examined chloride behavior in washing experiments by X-ray absorption near edge structure (XANES) and X-ray diffraction (XRD) for two kinds of fly ash: (1) fly ash collected in a bag filter with the injection of calcium hydroxide (Ca(OH)2) for acid gas removal (CaFA), and (2) fly ash collected in a bag filter with the injection of sodium bicarbonate (NaHCO3) for acid gas removal (NaFA). We found that the insoluble chlorides in both CaFA and NaFA combined calcium chloride (CaCl2), with some sodium chloride (NaCl) also possibly combined. Under some conditions, the combined CaCl2 and NaCl were released. In particular, when the liquid/solid ratio was greater than 3 or the washing frequency was doubled, less chlorine, insoluble chlorine, and CaCl2 were left in the residues of NaFA than in the residues of CaFA. As a result, it is desirable to use NaHCO3 as the alkaline reagent instead of Ca(OH)2 in the air pollution control system of incinerators for recycling fly ash as a raw material in the cement industry.
RESUMO
An expanded-bed granular activated carbon (GAC) anaerobic reactor was developed to treat terephthalate-containing wastewater. Terephthalate inhibits biological anaerobic degradation of terephthalate and methane production when present at a concentration of more than 150 mg/L. In the GAC anaerobic reactor developed here, degradation of terephthalate and other organic compounds occurred smoothly and stably with removal and methane fermentation ratios of more than 90% under a chemical oxygen demand (COD) loading rate of 4 kg COD/(m(3) d) and a terephthalate loading rate of 1 kg terephthalate/(m(3) d).
Assuntos
Reatores Biológicos , Ácidos Ftálicos/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Adsorção , Anaerobiose , Poluição Química da ÁguaRESUMO
The objective of this study was to evaluate the performance characteristics of a hyperthermophilic digester system that consists of an acidogenic reactor operated at hyperthermophilic (70 degrees C) conditions in series with a methane reactor operated at mesophilic (35 degrees C), thermophilic (55 degrees C), and hyperthermophilic (65 degrees C) conditions. Lab-scale reactors were operated continuously, and were fed with co-substrates composed of artificial kitchen garbage (TS 9.8%) and excess sludge (TS 0.5%) at the volumetric ratio of 20:80. In the acidification step, COD solubilization was in the range of 22-46% at 70 degrees C, while it was 21-29% at 55 degrees C. The average protein solubilization was 44% at 70 degrees C. The double bond fatty acid removal ratio at 70 degrees C was much higher than at 55 degrees C. These results suggested that the optimal operation conditions for the acidogenic fermenter were about 3.1 days of HRT and 4 days of SRT at 70 degrees C. Methane conversion efficiency and the VS removal percentage in the methanogenic step following acidification was around 65% and 64% on average at 55 degrees C, respectively. The optimal operational conditions for this system are acidogenesis performed at 70 degrees C and methanogenesis at 55 degrees C. The key microbes determined in the hyperthermophilic acidification step were Anaerobic thermophile IC-BH at 6.4 days of HRT and Thermoanaerobacter thermohydrosulfuricus DSM 567 at 2.4 days of HRT. These results indicated that the hyperthermophilic system provides considerable advantages in treating co-substrates containing high concentrations of proteins, lipids, and nonbiodegradable solid matter.
Assuntos
Archaea/classificação , Archaea/metabolismo , Técnicas de Cocultura/métodos , Microbiologia de Alimentos , Resíduos de Alimentos , Eliminação de Resíduos/métodos , Esgotos/microbiologia , Especificidade da EspécieRESUMO
The toxicity of seven phthalate esters (PAEs), dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), butylbenzyl phthalate (BBP), di-n-hexyl phthalate (DnHP), di-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DOP) to embryogenesis and larval development of the marine univalve Haliotis diversicolor supertexta was examined by means of two-stage embryo toxicity test. At the blastula stage, the normal embryonic development of H. diversicolor supertexta showed a good dose-response decrease when exposed to DMP, DEP, DBP, BBP, and DnHP. 9-h EC(50) values of DMP, DEP, DBP, BBP, and DnHP were 55.71, 39.13, 8.37, 2.65, and 3.32 mg/l, respectively. 9-h EC(50) values of DEHP and DOP were not available due to their low solubility. The toxicity order of seven tested PAEs was BBP>DnHP>DBP>DEP>DMP>DOP>DEHP. With the completion of metamorphosis as an experimental endpoint, the 96-h no-observed effect concentration values of DBP, DEHP and the other five tested PAEs were 0.022, 0.021, and 0.020 mg/l, respectively. Due to simple obtainment, convenient stimulation to spawn in the lab, greater sensitivity than mature species, and short culture time, the embryos of H. diversicolor supertexta have the potential to be utilized in acute toxicity test for at least PAEs.