Factors controlling the biodegradation of 17beta-estradiol, estrone and 17alpha-ethinylestradiol in different natural soils

We conducted a series of laboratory microcosm incubations with [(14)C]-labeled 17beta-estradiol (E2), estrone (E1) and 17alpha-ethinylestradiol (EE2) in 17 different natural soils to characterize hormone mineralization. A significantly higher mineralization was observed for E1 (2.0-37.6%) and E2 (4.2-50.2%) than for EE2 (0.5-2.6%) in all test soils after 21 days. Soil physical or chemical parameters were not related to estrogen mineralization. Although sorption parameters varied greatly for E2 (K(F)=21.9-317.5 mL g(-1)), for E1 (K(F)=46.0-517.5 mL g(-1)) and for EE2 (K(F)=29.9-326.1 mL g(-1)) this apparently did not control estrogen bioavailability since it showed no effects on hormone mineralization. In order to elucidate the controlling factors, experiments with combined additions of radiolabeled estrogens and different substrates were conducted. Additions of ammonium nitrate or alanine to soil samples generally increased EE2 mineralization, thus indicating N-limitation. Additions of glucose induced higher E2 and EE2 degradation in comparison to control samples which is attributed to co-metabolism. Additions of saw dust, catechol or streptomycin influenced the microbial population in the test soils and affected the mineralization of E2 and EE2. Thus, we clearly demonstrate that different microbial communities are responsible for E2 and EE2 degradation in soils. We suggest that EE2 is mineralized by white-rot fungi and E2 by bacteria.     

Photodegradation of the steroid hormones 17beta-estradiol (E2) and 17alpha-ethinylestradiol (EE2) in dilute aqueous solution

The photochemical transformation of natural estrogenic steroid 17beta-estradiol (E2) and the synthetic oral contraceptive 17alpha-ethinylestradiol (EE2) has been studied in dilute non buffered aqueous solution (pH 5.5-6.0) upon monochromatic (254 nm) and polychromatic (lambda>290 nm) irradiation. Upon irradiation at 254 nm, the quantum yields of E2 and EE2 photolysis were similar and evaluated to be 0.067+/-0.007 and 0.062+/-0.007, respectively. Upon polychromatic excitation, and by using phenol as chemical actinometer, the photolysis efficiencies have been determined to be 0.07+/-0.01 and 0.08+/-0.01 for E2 and EE2, respectively. For both estrogens, photodegradation by-products were identified with GC/MS and LC/MS. In a first step, a model compound--5,6,7,8-tetrahydro-2-naphthol (THN)--, which represents the photoactive phenolic group, was used to obtain basic photoproduct structural informations. Numerous primary and secondary products were observed, corresponding to hydroxylated phenolic- or quinone-type compounds.     

Bioaccumulation of 14C-17alpha-ethinylestradiol by the aquatic oligochaete Lumbriculus variegatus in spiked artificial sediment

A bioaccumulation study was performed with the endobenthic freshwater oligochaete Lumbriculus variegatus MULLER exposed to the radiolabelled synthetic steroid 17alpha-ethinylestradiol (14C-EE2) in a spiked artificial sediment. Concentration of total radioactivity increased constantly and almost linearly during 35 days of exposure. The accumulation factor normalised to worm lipid content and sediment TOC (AFlipid/OC) was 75 at the end of the uptake period, but a steady state was not reached. Uptake kinetics were calculated fitting the measured AFs to a kinetic rate equation for constant uptake from sediment using iterative non-linear regression analysis. After 10 days of elimination in contaminant-free sediment 50% of the accumulated total radioactivity was excreted by the worms. Extracts from L. variegatus sampled at the end of the uptake phase were analysed by thin layer chromatography (TLC). The results showed that 6% of the total radioactivity incorporated by the worms was 14C-EE2. After treatment of extracts with beta-glucuronidase the amount of 14C-EE2 increased to 84%. These results suggest that L. variegatus has the potency to accumulate high amounts of conjugated EE2. Hence, a transfer of EE2 to benthivores and subsequent secondary poisoning of predators might be possible.     

Behavior and prediction of photochemical degradation of chlorinated polycyclic aromatic hydrocarbons in cyclohexane

The photochemical degradation of 11 chlorinated polycyclic aromatic hydrocarbons (ClPAHs) and the corresponding 5 parent PAHs was examined to simulate the compound’s fate on aerosol surfaces. All the ClPAHs and PAHs decayed according to the first-order reaction rate kinetics. The photolysis rates of ClPAHs varied greatly according to the skeleton of PAHs; the rates of chlorophenanthrenes (ClPhes) and 1-chloropyrene were higher than those of corresponding parent PAHs, whereas chlorofluoranthenes, 7-chlorobenz[a]anthracene and 6-chlorobenzo[a]pyrene were more stable under irradiation compared to respective parent PAH. Considering the photoproducts of ClPhes detected, the oxidation could occur immediately at positions of the highest frontier electron density. Finally, the quantitative structure-property relationship models were developed for direct photolysis half-lives and average quantum yields of the ClPAHs and parent PAHs, in which the significant factors affecting photolysis were E_LUMO+1, total energy and surface area, and E_LUMO, E_LUMO − E_HOMO and total energy, respectively.     

Effect of fulvic acid on the photochemical degradation of methylparathion

Photochemical degradation of methylparathion (O,O,–dimethyl O-4 nitrophenylphosphorothioate) in the presence of fulvic acid (FA) between pH 2 and 7 was studied by differential pulse polarography (DPP). Fulvic acid and its photoproducts were not electro-active under the experimental conditions used in this study, and only the pesticide exhibited polarographic signals. Photolysis of methylparathion in acid media was sensitized by fulvic acid since the pesticide did not degrade in the absence of this compound. Methylparathion degradation was observed at each of the studied pHs. The reaction was first-order with rate constant values ranging from 3.3 × 10^?3 to 8.8 × 10^?3min^?1.     

Occurrence and microbial degradation of phthalate esters in Taiwan river sediments

Concentrations and microbial degradation rates were measured for eight phthalate esters (PAEs) found in 14 surface water and six sediment samples taken from rivers in Taiwan. The tested PAEs were diethyl phthalate (DEP), dipropyl phthalate (DPP), di-n-butyl phthalate (DBP), diphenyl phthalate (DPhP), benzylbutyl phthalate (BBP), dihexyl phthalate (DHP), dicyclohexyl phthalate (DCP), and di-(2-ethylhexyl) phthalate (DEHP). In all samples, concentrations of DEHP and DBP were found to be higher than the other six PAEs. DEHP concentrations in the water and sediment samples ranged from ND to 18.5 μg/l and 0.5 to 23.9 μg/g, respectively; for DBP the concentration ranges were 1.0–13.5 μg/l and 0.3–30.3 μg/g, respectively. Concentrations of DHP, BBP, DCP and DPhP were below detection limits. Under aerobic conditions, average degradation half-lives for DEP, DPP, DBP, DPhP, BBP, DHP, DCP and DEHP were measured as 2.5, 2.8, 2.9, 2.6, 3.1, 9.7, 11.1 and 14.8 days, respectively; under anaerobic conditions, respective average half-lives were measured as 33.6, 25.7, 14.4, 14.6, 19.3, 24.1, 26.4 and 34.7 days. In other words, under aerobic conditions we found that DEP, DPP, DBP, DPhP and BBP were easily degraded, but DEHP was difficult to degrade; under anaerobic conditions, DBP, DPhP and BBP were easily degraded, but DEP and DEHP were difficult to degrade. Aerobic degradation rates were up to 10 times faster than anaerobic degradation rates.     

Chlorinated hydrocarbons in sediments of the Elbe River and the Elbe Estuary

Eight sediment samples collected between Hamburg and Cuxhaven were analysed for organic micropollutants. Using three different methods the following compounds were determined: α-HCH, γ-HCH, HCB, PCB, DDT-family, pentachlorobenzene and octachlorostyrene.     

The role of organic ligands in ferrous-induced photochemical degradation of 2,4-dichlorophenoxyacetic acid

Recent studies have shown that hydrogen peroxide is generated in a ferrioxalate-induced photoreductive reaction, but information about the effect of organic ligands on the photochemical behaviour of ferrous species is limited. The degradation of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) by a ferrous-catalyzed oxidation in the presence of various ligands such as formate, citrate, malelate, oxalate, and ethylenediaminetetra-acetic acid (EDTA) was studied. The experiments were conducted under either dark or irradiated (350n m) conditions. Forty-two percent and 34% of 2,4-D were removed by the Fe(2+)/oxalate/UV and Fe(2+)/citrate/UV processes, respectively, after 30 min of reaction and oxidative intermediates were obtained in both cases. The presence of hydroxylated intermediates suggests that 2,4-D may be attacked by hydroxyl radicals, which are the products of the photo-Fenton-like reaction. As such, hydrogen peroxide was produced by the photolysis of ferrous oxalate or ferrous citrate, referred to hereafter as photogenerated H(2)O(2). As expected, the total removal percentage of 2,4-D jumped to 97% when 1mM of hydrogen peroxide (so-called spiked H(2)O(2)) was externally added to the reaction vessel to initiate the Fe(2+)/oxalate/UV process. Therefore, the treatment of 2,4-D by the Fe(2+)/oxalate/H(2)O(2)/UV system can be operated in two steps: the photolysis of ferrous oxalate first, followed by adding the spiked H(2)O(2) sometime after the commencement of the reaction. A two-phase model has been developed to describe this tandem ferrous-catalyzed photooxidation, which would help to achieve the mineralization of 2,4-D.     

Occurrence of carbon monoxide during organic waste degradation

The concentrations of carbon monoxide (CO) and other gases were measured in the emissions from solid waste degradation under aerobic and anaerobic conditions during laboratory and field investigations. The emissions were measured as room temperature headspace gas concentrations in reactors of 1, 30, and 150 L, as well as sucked gas concentrations from windrow composting piles and a biocell, under field conditions. The aerobic composting laboratory experiments consisted of treatments with and without lime. The CO concentrations measured during anaerobic conditions varied from 0 to 3000 ppm, the average being 23 ppm, increasing to 133 ppm when methane (CH4) concentrations were low. The mean/maximum CO concentrations during the aerobic degradation in the 2-L reactor were 101/194 ppm without lime, 486/2022 ppm with lime, and 275/980 ppm in the 150-L reactors. The presence of CO during the aerobic composting followed a rapid decline in O2 concentrations Significantly higher CO concentrations were obtained when the aerobic degradation was amended with lime, probably because of a more extreme depletion of oxygen. The mean/maximum CO concentrations under field conditions during aerobic composting were 95/1000 ppm. The CO concentrations from the anaerobic biocell varied from 20 to 160 ppm. The hydrogen sulfide concentrations reached almost 1200 ppm during the anaerobic degradation and 67 ppm during the composting experiments.     

Dioxin cycling in aquatic sediments: the Passaic River Estuary

The contribution of dechlorination reactions to the transformation of dioxins in river sediments was evaluated under a range of geochemical conditions mimicking freshwater, estuarine and marine environments, and interpreted in the light of recent evidence for their accumulation at the air-water interface. The yield of dechlorinated products increased with salinity, but never exceeded 20% of the initial dioxins present. Among the homologue groups in saline conditions, diCDDs were dominant at 32-47 mol% (8-16 nM). The production of 2,3,7,8-TCDD increased with decreasing salinity and in the presence of dissolved organic matter, exhibiting a maximum ratio (2,3,7,8-TCDD:non-2,3,7,8-TCDD) of 0.5. These differences in patterns may be related to the dominant microbial respiratory processes responsible for carbon turnover under the imposed conditions, and are strongly affected by the presence of organic matter. Based on these results, a conceptual dechlorination and carbon turnover model is proposed to help explain the likely reactivity of dioxins in the Passaic River Estuary.     

珠江口大气氮磷干湿沉降通量及其污染特征

为准确核定入海污染负荷和系统实施入海污染物总量控制,观测了珠江口地区大气氮磷的干湿沉降通量,并分析了其时空变异规律、化学组成特征以及主要的影响因素。结果显示,珠江口地区大气总氮和总磷的平均月沉降通量分别约为299.00、4.12kg/km2,其中湿沉降通量占总沉降通量的60%以上。干沉降和湿沉降通量均表现出明显的时空变异规律,前者的季节性变化主要受农业活动氮磷挥发的影响,而后者与年内降雨量分布以及季风作用下降雨云团来源的关系更为密切;沉降负荷的空间分布规律基本与不同区域受人类活动影响的特点相一致。由于不同污染来源和季风气候的影响,氮沉降化学组成的季节差异特征也较为明显,氨氮在秋冬季沉降中所占的比例明显高于春夏季,而有机氮则与之相反。     

Monitoring the photochemical degradation of triclosan in wastewater by UV light and sunlight using solid-phase microextraction

Photo solid-phase microextraction (photo-SPME) is applied for the first time to study the photochemical behavior of an emerging pollutant, triclosan, in real contaminated wastewater samples using a solar simulator. In this study, water samples are extracted by SPME and then, the fiber coating is irradiated for a selected time. This on-fiber procedure, so-called photo-SPME, followed by gas chromatography-mass spectrometry makes it possible to study photodegradation kinetics and the generation of byproducts. Several photoproducts were identified in the real samples including the 2,8-dichlorodibenzo-p-dioxin, dichlorophenols and a compound tentatively identified as other DCDD congener or a dichlorohydroxydibenzofuran. Accordingly, it was possible to postulate main photodegradation mechanisms. Photo-SPME demonstrated slower kinetics in wastewater than in spiked ultrapure water probably due to the presence of dissolved organic matter. This technique was extensively compared with conventional aqueous photodegradation showing high similarity. The influence of pH on the triclosan photolysis and on the triclosan-dioxin conversion was also investigated in wastewater. Photodegradation of triclosan and formation of 2,8-DCDD occurred independently of sample pH. This study represents an advance in the use of photo-SPME to understand the photochemical fate of environmental organic pollutants and demonstrates its clear advantages with real samples.     

Sediment-water distribution of perfluorooctane sulfonate (PFOS) in Yangtze River Estuary

Analysis of Perfluorooctane sulfonate (PFOS) distribution in water and sediment in Yangtze River Estuary showed that the estuary was a sink for PFOS. Salinity was an important parameter in controlling the sediment-water interactions and the fate or transport of PFOS in the aquatic environment. As the salinity (S‰) increased from 0.18 to 3.31, the distribution coefficient (K_d) between sediment and water linearly increased from 0.76 to 4.70 L g⁻¹. The study suggests that PFOS may be carried with the river water and transported for long distances before it reaches to the sea and largely scavenged to the sediment in the estuaries due to the dramatic change in salinity.     

Seasonal air-water exchange fluxes of polychlorinated biphenyls in the Hudson River Estuary

Polychlorinated biphenyls (PCBs) were measured in the air and water over the Hudson River Estuary during six intensive field campaigns from December 1999 to April 2001. Over-water gas-phase SigmaPCB concentrations averaged 1100 pg/m3 and varied with temperature. Dissolved-phase SigmaPCB concentrations averaged 1100 pg/L and displayed no seasonal trend. Uncertainty analysis of the results suggests that PCBs with 5 or fewer chlorines exhibited net volatilization. The direction of net air/water exchange could not be determined for PCBs with 6 or more chlorines. Instantaneous net fluxes of SigmaPCBs ranged from +0.2 to +630 ng m(-2) d(-1). Annual fluxes of SigmaPCBs were predicted from modeled gas-phase concentrations, measured dissolved-phase concentrations, daily surface water temperatures and wind speeds. The net volatilization flux was +62 microg m(-2) yr(-1), corresponding to an annual loss of +28 kg/yr of SigmaPCBs from the Hudson River Estuary for the year of 2000.     

Occurrence and behaviour of selected hydrophobic alkylphenolic compounds in the Danube River

Six hydrophobic alkylphenolic compounds were investigated for the first time simultaneously in four different matrices in the Danube River. Maximum sediment concentrations were 2.83, 2.10, 0.28, and 0.035 mg kg⁻¹ for nonylphenol, nonylphenol monoethoxylate, nonylphenol diethoxylate and octylphenol. Maximum levels in suspended particulate matter (SPM) were 0.18, 0.12, 0.10, and 0.003 mg kg⁻¹. No correlation between concentrations in SPM and sediments was found. Octylphenol monoethoxylate and octylphenol diethoxylate were recorded only in sediment at one location. In mussels and water only nonylphenol and octylphenol were found. Nonylphenol concentrations in mussels (up to 0.34 mg kg⁻¹) correlate with concentrations found in SPM and indicate a slight bioaccumulation. Concentrations in water were close to the limit of quantification. We assume in situ formation of nonylphenol monoethoxylate and nonylphenol in sediments at some locations. In some cases nonylphenol in sediments exceeded the provisional EU environmental quality standards.     

Occurrence of pharmaceutical and personal care products in Cau River,Vietnam

Environmental Science and Pollution Research - This study evaluated the occurrence of PPCPs in Cau River (Vietnam). Surface water and sediment samples were collected to determine PPCP...     

壬基酚及其短链聚氧乙烯醚在污泥和土壤中的存在和降解

壬基酚聚氧乙烯醚(NPnEO)是广泛使用的表面活性剂．在污水处理厂中会降解为具有内分泌干扰效应的短链产物和最终产物壬基酚(NP)。剩余污泥是其进入环境的重要途径。介绍了NP和短链NPnEO在污泥中的存在情况、污泥处理过程对其存在的影响、以及这些物质随污泥处置过程进入土壤后的降解。     

Heavy metals in coastal wetland sediments of the Pearl River Estuary, China

Sediment quality in coastal wetlands of the Pearl River Estuary was concerned since the wetlands were used for land reclamation, aquaculture and wildlife protection, and meanwhile served as one of the main ultimate sinks for large amount of heavy metals discharged from the rapidly developing Pearl River Delta. Total concentrations of heavy metal, such as Zn, Ni, Cr, Cu, Pb, and Cd, and their chemical speciation were investigated. Results showed that the sediments were significantly contaminated by Cd, Zn and Ni with concentration ranges of 2.79-4.65, 239.4-345.7 and 24.8-122.1mg/kg, respectively. A major portion (34.6-46.8%) of Pb, Cd, and Zn was strongly associated with exchangeable fractions, while Cu, Ni and Cr were predominantly associated with organic fractions, residual, and Fe-Mn oxide. Cd and Zn would be the main potential risk and the sediment quality is no longer meeting the demand of the current wetland utilization strategies.     

Occurrence and risk assessment of antidepressants in Huangpu River of Shanghai,China

Antidepressants are gaining public attention because of increasing reports of their occurrence in environment and their potential impact on ecosystems and human health. Continuous input of pharmaceuticals into rivers, through psychiatric hospital or wastewater treatment plant (WWTPs) effluent, may cause adverse effects on the aquatic ecosystems of the receiving water bodies. This work investigates the occurrence and sources of 8 antidepressants in main stream and tributaries of Huangpu River in Shanghai. The detected concentrations of the selected antidepressants ranged from low nanogram per liter to 42.9 ng L^?1 (fluoxetine) in main stream and ranged from low nanogram per liter to 33.7 ng L^?1 (fluoxetine) in tributaries. To study the effect of hospital or wastewater treatment plants (WWTPs) on environment, the upstream and downstream samples were analyzed. Generally, antidepressants had greater concentrations in downstream than that in upstream of the WWTPs or hospitals. It is suggesting that WWTPs and hospitals may introduce pollution into water environment. A preliminary risk assessment was conducted: none of the eight target compounds yielded risk quotient (RQ) values more than 0.1, thus indicating that no adverse effect is expected in water environment. These results will provide background data for future antidepressants pollution control and management in Shanghai, China.