垃圾渗出液中酚类物质的气相色谱分析

建立了一种用气相色谱法准确、快速测定垃圾渗出液中酚类物质的新方法。外标法定量分析 4 -甲基苯酚及苯酚。采用填装了 80～ 1 0 0目 Chromosorb WAW DCMS的玻璃填充柱 ,担体上涂渍了 2 % OV-1 7,2 .5% QF-1的固定液 ,分离酚类物质效果较好 ,线性范围为 1 0 0～ 1 50 0 mg/ L,相关系数为 0 .9996,方法回收率为 94 .7%。     

假丝酵母菌对高浓度苯酚的降解效果及SDS对其生长影响

从含酚废水处理池污泥中驯化得到苯酚降解菌——假丝酵母菌FD-1,通过试验考察FD-1对高浓度苯酚废水的降解效果,以及十二烷基磺酸钠(SDS)对高浓度苯酚废水中FD-1菌株生长的影响。试验表明,假丝酵母菌FD-1对苯酚的最大降解质量浓度为1 500 mg/L,降解时间为30 h。当苯酚质量浓度不超过1 000 mg/L时,添加适量的SDS可以显著提高苯酚降解速率,进而缩短苯酚降解时间,SDS的最佳投加量为100 mg/L,超过150 mg/L时FD-1生长受到抑制。     

Phytoremediation of phenol using Polygonum orientale,including optimized conditions

Removing phenol from wastewater has become a major challenge of international concern. Phytoremediation is a novel and eco-friendly method and is attracting an increasing amount of attention for treating phenol in wastewater. We studied the ability of Polygonum orientale, which is frequently present around water bodies and in wetlands in China, to phytoremediate phenol. We determined the inhibition concentration for phenol on P. orientale using emergency toxicology experiments and morphological observations. Isothermal and kinetic models were created to assess the adsorption process involved in phenol removal. Comparison tests in sterile conditions demonstrated that metabolic removal was the main way in which the phenol concentrations were decreased, and removal by adsorption played a smaller role. An orthogonal test was performed to determine the optimum conditions under which P. orientale will remove phenol, and these were found to be an initial phenol concentration of 5 mg L^?1, 100 % natural light, and a 13-day treatment time. These results provide a theoretical basis for increasing our understanding of the mechanisms involved in the removal of phenol by P. orientale and will help in developing its application in the greening of urban areas to provide both phytoremediation and esthetic landscaping.     

Bioaerosol exposure assessment in the workplace: the past, present and recent advances

Louis Pasteur described the first measurements of airborne microorganisms in 1861. A century later, the inhalation of spores from thermophilic microorganisms was shown to induce attacks of farmers' lung in patients with this disease, while endotoxins originating from Gram-negative bacteria were identified as causal agents for byssinosis in cotton workers. Further epidemiological and toxicological studies have demonstrated inflammatory, respiratory, and pathogenic effects following exposure to bioaerosols. Exposure assessment is often confounded by the diversity of bioaerosol agents in the environment. Microorganisms represent a highly diverse group that may vary in toxicity. Fungi and bacteria are mainly quantified as broad groups using a variety of viable and nonviable assessment methods. Endotoxins and β(1 → 3)-glucans are mainly measured by their activity in the Limulus amebocyte lysate assay, enzymes by immuno-chemical methods and mycotoxins by liquid chromatography-mass spectrometry. Few health-based occupational exposure limits (OELs) are available for risk assessment. For endotoxins, a health-based OEL of 90 endotoxin units m(-3) has been proposed in the Netherlands. A criteria document for fungal spores recently proposed a lowest observed effect level of 100,000 spores m(-3) for non-pathogenic and non-mycotoxin producing species based on inflammatory respiratory effects. Recent developments in bioaerosol assessment were presented at the Organic Dust Troms? Symposium including molecular biological methods for infectious agents and organisms that are difficult to cultivate; studies of submicronic and hyphal fragments from fungi; the effect of biodiversity of microorganisms in asthma studies; and new/improved measurement methods for fungal antigens, enzymes and allergens. Although exposure assessment of bioaerosol agents is complex and limited by the availability of methods and criteria, the field is rapidly evolving.     

Occurrences of six steroid estrogens from different effluents in Beijing, China

Concentration levels of six natural and anthropogenic origin steroid estrogens, namely, diethylstilbestrol (DES), estrone (E1), estradiol (E2), estriol (E3), ethinylestradiol (EE2), and estradiol-17-valerate (Ev), from different effluents in Beijing were assessed. Sampling sites include two wastewater treatment plants (WWTPs), a chemical plant, a hospital, a pharmaceutical factory, a hennery, and a fish pool. In general, concentrations of estrogens in the effluents varied from no detection (nd) to 11.1 ng/l, 0.7 to 1.2 × 10³ ng/l, nd to 67.4 ng/l, nd to 4.1 × 10³ ng/l, nd to 1.2 × 10³ ng/l, and nd to 11.2 ng/l for DES, E1, E2, EE2, E3, and Ev, respectively. The concentration levels of steroid estrogens from different effluents decreased in the order of pharmaceutical factory and WWTP inlets > hospital > hennery > chemical factory > fish pool. This study indicated that natural estrogens E1, E2, and E3 and synthetic estrogen EE2 are the dominant steroid estrogens found in the different Beijing effluents. For source identification, an indicator (hE = E3/(E1 + E2 + E3)) was used to trace human estrogen excretion. Accordingly, hE in effluents from the hospital and WWTP inlets exceeded 0.4, while much smaller values were obtained for the other effluents. Human excretions were the major contributor of natural estrogens in municipal wastewater. Estimation results demonstrated that direct discharge was the major contributor of steroid estrogen pollution in receiving waters.     

The potential of different bio adsorbents for removing phenol from its aqueous solution

The use of natural resources for the removal of phenol and phenolic compounds is being looked upon by researchers in preference to other prevailing methods. In the present study, different biosorbents, brown algae (Padina pavonia), fresh water macrophyta (Ceratophyllum demersum), and black tea residue, were tested as adsorbent for the removal of phenol from aqueous solutions. The optimum conditions for maximum adsorption in terms of concentration of the adsorbate and pH were identified. The results show that the initial concentration increases as the removal of phenol increases in C. demersum; in the case of the other two adsorbents, the initial concentration increases as the removal of phenol decreases, especially for an initial concentration lower than 100 and 1,000 μg/L for P. pavonia and black tea residue, respectively. Maximum percentage removal of phenol by each adsorbent is 77, 50.8, and 29 % for C. demersum, P. pavonia, and black tea residue, respectively. Also, the biosorption capacity was strongly influenced by the pH of the aqueous solution with an observed maximum phenol removal at pH of around 6–10. The first biosorbent (black tea residue) displays the maximum adsorption capacity at a pH of 10 with a percentage sorption capacity of 84 %; P. pavonia revealed a greater adsorption percentage at pH?10, reaching 30 %, while for C. demersum, the removal of phenol increases with the increase in initial pH up to 6.0 and decreases drastically with further increase in initial pH. The Freundlich, Langmuir, and Brauner–Emmet–Teller adsorption models were applied to describe the equilibrium isotherms. The results reveal that the equilibrium data for all phenol adsorbents fitted the Freundlich model which seemed to be the best-fitting model for the experimental results with similar values of coefficient of determination.     

Time dependent influx and efflux of phenol by immobilized microbial consortium

Phenol, like many other organic solvents, is toxic to micro-organisms even at low concentrations. However, some micro-organisms can withstand this toxicity to a certain concentration. To observe the uptake mechanism of phenol, bacteria were isolatedfrom a petroleum refinery effluent and identified. Study was carried out to understand the effect of varying sub-lethal concentrations of phenol, on all the isolated individual bacterial cultures. Out of the bacteria isolated, Serratia liquefaciens was found to tolerate phenol concentration up to 1500 mg l^-1. A microbial consortium of the isolated bacteriawas formulated and immobilized. Individual cultures were also immobilized and uptake of phenol by the immobilized micro-organisms was observed in a nutrient-rich and nutrient-stressed medium containing phenol as a sole source of carbon. A time-dependent uptake of phenol was exhibited by the micro-organismsin nutrient-stressed medium, after which a sudden increase in phenol concentration occurred in the extracellular medium, till it reached back to the initial concentration. This was attributedto an active efflux mechanism adopted by the micro-organisms to withstand the toxic shock.     

Almond shell activated carbon: adsorbent and catalytic support in the phenol degradation

In this work, two technologies are studied for the removal of phenol from aqueous solution: dynamic adsorption onto activated carbon and photocatalysis. Almond shell activated carbon (ASAC) was used as adsorbent and catalytic support in the phenol degradation process. The prepared catalyst by deposition of anatase TiO₂ on the surface of activated carbon was characterized by scanning electron microscopy, sorption of nitrogen, X-ray diffraction, Fourier transform infrared (FT-IR) spectroscopy, and pH_ZPC point of zero charge. In the continuous adsorption experiments, the effects of flow rate, bed height, and solution temperature on the breakthrough curves have been studied. The breakthrough curves were favorably described by the Yoon–Nelson model. The photocatalytic degradation of phenol has been investigated at room temperature using TiO₂-coated activated carbon as photocatalyst (TiO₂/ASAC). The degradation reaction was optimized with respect to the phenol concentration and catalyst amount. The kinetics of disappearance of the organic pollutant followed an apparent first-order rate. The findings demonstrated the applicability of ASAC for the adsorptive and catalytic treatment of phenol.     

Natural Jordanian zeolite: removal of heavy metal ions from water samples using column and batch methods

The adsorption behavior of natural Jordanian zeolites with respect to Cd(2 + ), Cu(2 + ), Pb(2 + ), and Zn(2 + ) was studied in order to consider its application to purity metal finishing drinking and waste water samples under different conditions such as zeolite particle size, ionic strength and initial metal ion concentration. In the present work, a new method was developed to remove the heavy metal by using a glass column as the one that used in column chromatography and to make a comparative between the batch experiment and column experiment by using natural Jordanian zeolite as adsorbent and some heavy metals as adsorbate. The column method was used using different metal ions concentrations ranged from 5 to 20 mg/L with average particle size of zeolite ranged between 90 and 350 mum, and ionic strength ranged from 0.01 to 0.05. Atomic absorption spectrometry was used for analysis of these heavy metal ions, the results obtained in this study indicated that zeolitic tuff is an efficient ion exchanger for removing heavy metals, in particular the fine particle sizes of zeolite at pH 6, whereas, no clear effect of low ionic strength values is noticed on the removal process. Equilibrium modeling of the removal showed that the adsorption of Cd(2 + ), Cu(2 + ), Pb(2 + ), and Zn(2 + ) were fitted to Langmuir, Freundlich and Dubinin-Kaganer-Radushkevich (DKR). The sorption energy E determined in the DKR equation (9.129, 10.000, 10.541, and 11.180 kJ/mol for Zn(2 + ), Cu(2 + ), Cd(2 + ) and Pb(2 + ) respectively) which revealed the nature of the ion-exchange mechanism.     

In vitro bioassay for reactive toxicity towards proteins implemented for water quality monitoring

Reactive organic chemicals comprise a large number of compounds with a variety of reactive moieties. While most assays for reactive toxicity focus on DNA damage, reactivity towards proteins can also lead to irreparable damage, but reactivity towards proteins is typically not included in any test battery for water quality assessment. Glutathione (GSH) is a small tripeptide whose cysteine moiety can serve as a model for nucleophilic sites on proteins. GSH is also an important indicator of detoxification processes and the redox status of cells and due to its protective role, depletion of GSH ultimately leads to adverse effects. A bioassay based on genetically modified Escherichia coli strains was used to quantify the specific reactivity towards the protein-like biological nucelophile GSH. The significance of GSH for detoxification was assessed by comparing the growth inhibition induced by reference chemicals or water samples in a GSH-deficient strain to its fully functional parent strain. The GSH deficient strain showed the same sensitivity as the GSH proficient strain to non-reactive and DNA damaging chemicals, but was more sensitive to chemicals that attack cysteine in proteins. The difference in effect concentrations for 50% inhibition of growth assessed as biomass increase (EC(50)) between the two strains indicates the relevance of GSH conjugation as a detoxification step as well as direct reactivity with cysteine-containing proteins. Seven reference compounds serving as positive and negative controls were investigated. The E. coli strain that lacks GSH was four times more sensitive towards the positive control Sea-Nine, while negative controls benzo[a]pyrene, 2-aminoanthracene, phenol, t-butylhydroquinone, methyl methane sulfonate and 4-nitroquinoline oxide showed equal effect concentrations in both strains. Water samples collected across an indirect potable reuse scheme representing the complete water cycle from sewage to drinking water in South East Queensland, Australia were used to evaluate the applicability of the E. coli assay for reactive toxicity in water samples. While the EC(50) values of the GSH+ strain showed similar trends as in other biological endpoints over the various treatment chains, the specific response indicative of protein damage was only observed in samples that had undergone chlorination as a disinfection process. High natural organic matter or other matrix components disturbed the bioassay so much that we recommend it for future routine testing only in tertiary treated water or drinking water.     

Assessment of phenol infiltration resilience in soil media by HYDRUS-1D transport model for a waste discharge site

The movement of contaminants through soil imparts a variety of geo-environmental problem inclusive of lithospheric pollution. Near-surface aquifers are often vulnerable to contamination from surface source if overlying soil possesses poor resilience or contaminant attenuation capacity. The prediction of contaminant transport through soil is urged to protect groundwater from sources of pollutants. Using field simulation through column experiments and mathematical modeling like HYDRUS-1D, assessment of soil resilience and movement of contaminants through the subsurface to reach aquifers can be predicted. An outfall site of effluents of a coke oven plant comprising of alarming concentration of phenol (4–12.2 mg/L) have been considered for studying groundwater condition and quality, in situ soil characterization, and effluent characterization. Hydrogeological feature suggests the presence of near-surface aquifers at the effluent discharge site. Analysis of groundwater of nearby locality reveals the phenol concentration (0.11–0.75 mg/L) exceeded the prescribed limit of WHO specification (0.002 mg/L). The in situ soil, used in column experiment, possess higher saturated hydraulic conductivity (K _S ?=?5.25?×?10^?4 cm/s). The soil containing 47 % silt, 11 % clay, and 1.54 % organic carbon content was found to be a poor absorber of phenol (24 mg/kg). The linear phenol adsorption isotherm model showed the best fit (R ²?=?0.977, RMSE?=?1.057) to the test results. Column experiments revealed that the phenol removal percent and the length of the mass transfer zone increased with increasing bed heights. The overall phenol adsorption efficiency was found to be 42–49 %. Breakthrough curves (BTCs) predicted by HYDRUS-1D model appears to be close fitting with the BTCs derived from the column experiments. The phenol BTC predicted by the HYDRUS-1D model for 1.2 m depth subsurface soil, i.e., up to the depth of groundwater in the study area, showed that the exhaustion point was reached within 12 days of elapsed time. This clearly demonstrated poor attenuation capacity of the soil to retard migration of phenol to the groundwater from the surface outfall site. Suitable liner, based on these data, may be designed to inhibit subsurface transport of phenol and thereby to protect precious groundwater from contamination.     

Artemia salina as test organism for assessment of acute toxicity of leachate water from landfills

Artemia salina has, for the first time, been used as test organism for acute toxicity of leachate water from three landfills (the municipal landfills at Kristianstad, Sweden and Siauliai, Lithuania, and an industrial landfill at Stena fragmenting AB, Halmstad, as well as for leachate from Kristianstad treated in different ways in a pilot plan). Artemia can tolerate the high concentrations of chloride ions found in such waters. Large differences in toxicities were found, the leachate from Siauliai being the most toxic one. To increase the selectivity in the measurements, a fractionation was done by using ion exchange to separate ammonium/ammonia and metal ions from the leachate, and activated carbon adsorbents for organic pollutants. The influence of some metals and phenol compounds on the toxicity was investigated separately. It was found that most of the toxicity emanated from the ammonium/ammonia components in the leachate. However, there was also a significant contribution from organic pollutants, other than phenol compounds, since separate experiments had in this latter case indicated negligible impact. The concentrations of metals were at a level, shown by separate experiments, where only small contribution to the toxicity could be expected.     

Atmospheric heavy metals in tropical South America during the past 22,000 years recorded in a high altitude ice core from Sajama, Bolivia

V, Co, Cu, Zn, As, Rb, Sr, Ag, Cd, Ba, Pb, Bi and U have been analysed by inductively coupled plasma sector field mass spectrometry in various sections of a dated snow/ice core drilled at an altitude of 6542 m on the Sajama ice cap in Bolivia. The analysed sections were dated from the Last Glacial Stage ( approximately 22,000 years ago), the Mid-Holocene and the last centuries. The observed variations of crustal enrichment factors (EFc) for the various metals show contrasting situations. For V, Co, Rb, Sr and U, EFc values close to unity are observed for all sections, then showing that these elements are mainly derived from rock and soil dust. For the other metals, clear time trends are observed, with a pronounced increase of EFc values during the 19th and 20th centuries. This increase shows evidence of metal pollution associated with human activity in South America. For Pb an important contribution was from gasoline additives. For metals such as Cu, Zn, Ag and Cd an important contribution was from metal production activities, with a continuous increase of production during the 20th century in countries such as Peru, Chile and Bolivia.     

高效液相色谱法同时测定苯酚及其氯化中间产物

采用高效液相色谱法同时测定次氯酸钠氧化降解苯酚过程中苯酚及其5种氯化中间体,确定了检测波长,讨论了pH值对测定的影响。方法线性良好,苯酚、2-氯苯酚、4-氯苯酚、2,6-二氯苯酚、2,4-二氯苯酚、2,4,6-三氯苯酚的检出限分别为0．01mg／L、0．02mg／L、0．02mg／L、0．02mg／L、0．02mg／L、0．02mg／L,标准溶液测定的相对标准偏差≤0．8％,样品加标回收率为96．0％～102％。     

Comparative study of fluorogenic and chromogenic media for specific detection of environmental isolates of thermotolerant Escherichia coli

In a field study 78 water samples were analysed employingFluorocult Brilla Broth (BB) and its performance was comparedwith standard MPN procedure. Out of 78 water samples analysed 56(71.7%) samples yielded positive reactions in BB whereas, 50(64.1%) samples were positive by standard fecal coliform test.A comparative study of fluorogenic and chromogenic mediacontaining substrate -D glucuronide for specificdetection of environmental isolates of 313 thermotolerant E.coli has been undertaken. Five fluorogenic media wereused: Fluorocult MacConkey agar (MCA), Fluorocult ECD agar(ECD), Fluorocult VRB agar (VRB), Fluorocult E. coli0157:H7 agar (ECH7) and Fluorocult Brilla Broth (BB) andChromogenic Chromocult agar (CCA). BB and CCA were found to behighly specific and sensitive media to detect E. coli asall E. coli yielded positive reaction on them. On ECH7 andECD agar 67.5 and 64.9 of E. coli isolates gave positivereaction, respectively. Low sensitivity was observed in case ofMCA and VRB agar in detecting E. coli. The performance ofBB appears to be better when compared with standard MPNprocedure employing MacConkey broth/Brilliant green bile brothin detecting E. coli in drinking water.     

Behaviour of selected endocrine-disrupting chemicals in three sewage treatment plants of Beijing, China

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), 17α-estradiol (17α-E2), 17β-estradiol (E2), estriol (E3) and 17α-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 17α-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 17α-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.     

Bio-analytical and chemical characterisation of offshore produced water effluents for estrogen receptor (ER) agonists

The in vitro estrogen receptor (ER) agonist potency and C1 to C9 alkyl substituted phenol content of offshore produced water effluents collected from the UK sector of the North Sea were determined using a combination of bio-analytical and chemical analysis techniques. An in vitro reporter gene assay was used to determine ER agonist potency, whilst gas chromatography coupled to mass spectrometry (GC-MS) was used to quantify the concentration of alkylphenols. The in vitro ER agonist potency was highly variable and ranged from less than the limit of detection (theoretically 0.03 ng 17beta-estradiol (E2) l(-1)) to 91 ng E2 l(-1). C1 to C5 alkylphenol concentrations were also highly variable ranging from 5 to 1600 microg l(-1) with a median concentration of 206 microg l(-1). These data reflect the highly variable composition of produced water discharges from different fields. The observed poor correlation of the alkylphenol isomer content and ER agonist activity suggests that other compounds present in the produced water discharges may be responsible for the ER agonist activity observed. It is recommended that further work be performed to characterise the full range of ER agonists present in offshore produced water discharges.     

The continuous monitoring of field water samples with a novel multi-channel two-stage mini-bioreactor system

Toxicity monitoring of field water samples was performed using a novel multi-channel two-stage mini-bioreactor system and genetically engineered bioluminescent bacteria for the continuous monitoring and classification of the toxicity present in the samples. The toxicity of various samples spiked with known endocrine disrupting chemicals and phenol was also investigated for system characterization. The field samples used in this study were obtained from two different sites on a monthly basis--from a drinking water treatment plant, referred to as site N, and from a stream near a dam which is currently being constructed, referred to as site T. These samples were either pumped or injected into the second mini-bioreactors to initiate the toxicity test. Most of the samples did not show any specific toxicity. However, one sample showed to have, based upon the detection results, and was deemed toxic. The samples spiked with phenol showed possible responses in the DPD2540 and TV1061 channels, indicating the occurrence of both membrane and protein damage due to phenol. In the tests using an endocrine disrupting chemical, bisphenol A, DNA damage was detected in the DPD2794 channel with a concentration of 2 ppm. Finally, a simple but novel early warning protocol that can be used in a drinking water reservoir and a suspected place where effluents of toxic materials enter the water sourse was suggested with a schematic diagram. In conclusion, this system showed good feasibility for use as a toxicity monitoring system in the field and as an early warning system, indicating if effluents are toxic.     

A new <Emphasis Type="Italic">P. putida</Emphasis> instrumental toxicity bioassay

Here, we present a new toxicity bioassay (CO₂-TOX), able to detect toxic or inhibitory compounds in water samples, based on the quantification of Pseudomonas putida KT2440 CO₂ production. The metabolically produced CO₂ was measured continuously and directly in the liquid assay media, with a potentiometric gas electrode. The optimization studies were performed using as a model toxicant 3,5-DCP (3,5-dichlorophenol); later, heavy metals (Pb²⁺, Cu²⁺, or Zn²⁺) and a metalloid (As⁵⁺) were assayed. The response to toxics was evident after 15 min of incubation and at relatively low concentrations (e.g., 1.1 mg/L of 3,5-DCP), showing that the CO₂-TOX bioassay is fast and sensitive. The EC₅₀ values obtained were 4.93, 0.12, 6.05, 32.17, and 37.81 mg/L for 3,5-DCP, Cu²⁺, Zn²⁺, As⁵⁺, and Pb²⁺, respectively, at neutral pH. Additionally, the effect of the pH of the sample and the use of lyophilized bacteria were also analyzed showing that the bioassay can be implemented in different conditions. Moreover, highly turbid samples and samples with very low oxygen levels were measured successfully with the new instrumental bioassay described here. Finally, simulated samples containing 3,5-DCP or a heavy metal mixture were tested using the proposed bioassay and a standard ISO bioassay, showing that our test is more sensible to the phenol but less sensible to the metal mixtures. Therefore, we propose CO₂-TOX as a rapid, sensitive, low-cost, and robust instrumental bioassay that could perform as an industrial wastewater-process monitor among other applications.     

Determination of Steroid Estrogens in Wastewater Treatment Plant of A Controceptives Producing Factory

Steroid estrogens such as estrone (E1), 17β-estradiol (E2), estriol (E3), and 17α-ethynylestradiol (EE2) have been suspected to be the main contaminants, which can affect the endocrine system of animals. Many authors have investigated these chemicals in the domestic wastewater treatment plants (WTP). However, wastewater from industries producing steroid contraceptives has not got ample attention. From the environmental point of view, the four steroids are very significant because even very low concentrations (ng/L) can cause reproductive disturbances in human, livestock and wildlife. The main purpose of the present investigation was to develop an analytical method for the determination of the four steroid estrogens present in WTP of a pharmacy factory, mainly producing contraceptive medicine in Beijing, China. Analysis was performed by solid-phase extraction (SPE) system and liquid chromatography combined with tandem mass spectrometry (LC/MS/MS). The average recoveries from effluent samples ranged from 88% to 103% and the precision of the method ranged from 9% to 4%. Based on 0.5-L wastewater samples, the limit of quantification (LOQ) was determined at 0.7 ng/L for E1, 0.8 for E2, 0.9 ng/L for E3, and 0.5 ng/L for EE2 in influent, and 1.0 ng/L for E2 and EE2, and 2.0 ng/L for E1 and E3 in effluent. In the influent samples, average concentrations of 80, 85, 73 and 155 ng/L were determined for E1, E2, E3 and EE2, respectively, showing that they were removed in this WTP to the extent of 79, 73, 85 and 67%, respectively.