Canine toys and training devices as sources of exposure to phthalates and bisphenol A: Quantitation of chemicals in leachate and in vitro screening for endocrine activity

Chewing and mouthing behaviors exhibited by pet dogs are likely to lead to oral exposures to a variety of environmental chemicals. Products intended for chewing and mouthing uses include toys and training devices that are often made of plastics. The goal of the current study was to determine if a subset of phthalates and bisphenol A (BPA), endocrine disrupting chemicals commonly found in plastics, leach out of dog toys and training devices (bumpers) into synthetic canine saliva. In vitro assays were used to screen leachates for endocrine activity. Bumper leachates were dominated by di-2-ethylhexyl phthalate (DEHP) and BPA, with concentrations reaching low μg mL⁻¹ following short immersions in synthetic saliva. Simulated chewing of bumpers during immersion in synthetic saliva increased concentrations of phthalates and BPA as compared to new bumpers, while outdoor storage had variable effects on concentrations (increased DEHP; decreased BPA). Toys leached substantially lower concentrations of phthalates and BPA, with the exception of one toy which leached considerable amounts of diethyl phthalate. In vitro assays indicated anti-androgenic activity of bumper leachates, and estrogenic activity of both bumper and toy leachates. These results confirm that toys and training devices are potential sources of exposure to endocrine disrupting chemicals in pet dogs.     

4A沸石去除水中Pb2＋的研究

在静态条件下，研究了4A沸石对废水中Pb2＋的吸附性能，并探讨了影响吸附的因素。实验表明：当温度为30℃，废水pH为5～6，0．01g4A沸石对100mg／LPb2＋溶液10mL吸附20min，Pb2＋的去除率可达到99％以上。在实验研究条件下，4A沸石对Pb2＋的吸附符合Langmuir和Freundlich等温吸附方程，相关系数为0．9819和0．9998。经计算，4A沸石对Pb2＋的饱和吸附量为125mg／g。4A沸石吸附水中Pb2＋达到吸附平衡的时间较短；溶液pH值的变化对吸附效果影响不显著；温度从室温略微升高，Pb2＋的去除率略有增大。吸附在4A沸石上的Pb“可回收利用，处理后的4A沸石可以再生，且重复使用性能较好。     

小议火电厂总量减排核查要点

从资料核查、在线监测设备核查、集控系统核查及现场核查4个环节详细介绍了火电厂总量减排现场核查的要点。对核查中出现的问题进行总结及分析,为同类环境管理工作提供参考。     

Relationships between vitamin A and PCBs in grey seal mothers and pups during lactation

A previous study has shown a simultaneous increase of vitamin A and PCBs in grey seal (Halichoerus grypus) milk at late lactation (Debier et al., 2004). Here we sought to understand this unexpected relationship by comparing the dynamics of vitamin A and PCBs in the different tissue compartments of transfer. Lactating grey seals and their pups were sampled longitudinally in Scotland during the 2006 breeding season. As blubber reserves decreased, concentrations of vitamin A and PCBs increased during lactation in the inner layer of maternal blubber. A concomitant rise was observed in milk and consequently in the serum of suckling pups. The similar dynamics of vitamin A and PCBs in milk and inner blubber suggest a common mechanism of mobilisation from maternal body stores and transfer into the milk. A panel data analysis highlighted a negative impact of PCBs in milk and pup serum on vitamin A status in pup serum.     

Risk assessment of xenoestrogens in a typical domestic sewage-holding lake in China

Release of domestic sewage leads to accumulation of xenoestrogens in holding waters, especially in closed or semi-enclosed waters such as lakes. In the study, the occurrence, distribution, estrogenic activity and risk of eight xenoestreogens were evaluated in Lake Donghu, China. Nonylphenol (NP), octylphenol (OP), and bisphenol A (BPA) were identified as the main xenoestrogens ranging from tens of ng L⁻¹ (in the surface water) or ng g⁻¹ dw (in the suspended particles and sediment) to tens of μg L⁻¹ or μg g⁻¹ dw. The sum of 17β-estradiol equivalents (∑EEQs) ranged from 0.32 to 45.02 ng L⁻¹ in the surface water, 0.53 to 71.86 ng g⁻¹ dw in the suspended particles, and 0.09 to 24.73 ng g⁻¹ dw in the sediment. Diethylstilbestrol (DES) was determined as the main contributor to ∑EEQs followed by NP. The risk assessment showed a higher risk in the surface water than in the suspended particles and sediment in such domestic sewage-holding lake.     

Parental phenols exposure and spontaneous abortion in Chinese population residing in the middle and lower reaches of the Yangtze River

Widespread use of phenols has led to ubiquitous exposure to phenols. In experimental animals, phenols increased resorptions, reduced live litter size and fetal body weights. However, there are limited epidemiological evidences of the relationships between exposure to phenols and pregnancy outcomes. We evaluated the associations between parental urinary levels of various phenols and spontaneous abortion in a Chinese population residing in the middle and lower reaches of the Yangtze River. A case-control study was conducted that included 70 case couples with medically unexplained spontaneous abortion and 180 control couples who did not have a history of spontaneous abortion and had at least one living child. Both parental urinary phenols were measured by ultra-high performance liquid chromatography-tandem mass spectrometry including bisphenol A (BPA), benzophenone-3 (BP-3), 2,3,4-trichlorophenol (2,3,4-TCP), pentachlorophenol (PCP), 4-n-octylphenol (4-n-OP) and 4-n-nonylphenol (4-n-NP). Compared with the low exposure group, there was an increased risk of spontaneous abortion with high paternal urinary PCP concentration [odds ratio (OR) = 2.09, 95% Confidence Interval (CI), 1.05–4.14], and maternal exposure to 4-n-OP and alkylphenol(s) also significantly increased the risk of spontaneous abortion (OR = 2.21, 95% CI, 1.02–4.80; OR = 2.81, 95% CI, 1.39–5.65, respectively). Our study firstly provides the evidence that paternal PCP exposure, maternal 4-n-OP and alkylphenol(s) exposure are associated with spontaneous abortion in humans.     

Removal of tetrabromobisphenol A by conventional activated sludge, submerged membrane and membrane aerated biofilm reactors

The goal of this study was to compare removal efficiencies of tetrabromobisphenol A (TBBPA) using typical wastewater treatment technologies, and to identify the most significant mechanisms of removal. Two types of municipal wastewater reactors were studied: a full-scale conventional activated sludge (CAS) reactor with tertiary treatment; and three pilot-scale membrane bioreactors (MBRs) having different sludge retention times (SRTs). All four reactors were fed the same influent. A third reactor type, a membrane aerated biofilm reactor (MABR) was fed tap water, ammonia, and TBBPA. TBBPA in municipal influent ranged from 1 to 41 ng L⁻¹ (n = 10). The CAS effluent had an average TBBPA concentration of 0.7 ± 1.3 ng L⁻¹ (n = 3). Effluent concentrations from the MBRs were an average of 6 ± 6 ng L⁻¹ TBBPA (n = 26). Significant TBBPA removal was observed in the MABR throughout the 5 week of study (p ? 0.05). Removal of TBBPA from wastewater treatment was found to be due to a combination of adsorption and biological degradation. Based on experimental results, nitrification is likely a key process therein. No significant relationship between removal of TBBPA and SRT was identified (p ? 0.05).     

液相色谱-质谱法测定土壤中四溴双酚A和六溴环十二烷

文章建立了液相色谱-串联四级杆质谱仪同时测定土壤中四溴双酚A及3种六溴环十二烷同分异构体的分析方法。土壤样品经快速溶剂仪萃取，全自动凝胶净化系统净化后，使用液相色谱-串联四级杆质谱仪，负离子电喷雾多反应监测模式监测，内标法定量分析。结果表明，土壤中四溴双酚A、α-六溴环十二烷、β-六溴环十二烷和γ-六溴环十二烷的检出限为0.1~1.2 pg/g，加标回收率为81.8%~113%，相对标准偏差小于10%。该方法分析时间短，灵敏度高，操作简单，对电子固废拆解场地中的179个土壤样品进行分析，取得满意结果。     

Evaluation and validation of two different chromatographic methods (HPLC and LC-MS/MS) for the determination and confirmation of ochratoxin A in pig tissues

This study was undertaken to compare two different analytical methods for the determination and confirmation of ochratoxin A (OTA) in blood serum, kidney and liver of pigs. Sample clean-up was based on liquid-liquid phase extraction. The detection of OTA was accomplished with high-performance liquid chromatography (HPLC) combined either with fluorescence detection (FL) or electro spray ionization (ESI+) tandem mass spectrometry (MS–MS). Comparative method evaluation was based on the investigation of 90 samples of blood serum, kidney and liver per animal originating from different regions of Serbia. The analytical results are discussed in view of the respective method validation data and the corresponding experimental protocols. In general, analytical data obtained with (LC–MS–MS) liquid chromatography electro spray tandem mass spectro metry detection offered comparable good results at the sub-ppb concentration level. The results indicate that the liquid chromatography electro spray tandem mass spectrometric (LC-MS/MS) method was more specific and sensitive for the analysis and confirmation of ochratoxin A in pig tissues then high pressure liquid chromatography (HPLC) method after methylation of OTA.     

Biosorption of nickel(II) from aqueous solution by Aspergillus niger: Response surface methodology and isotherm study

In the present study, the effects of biosorbent Aspergillus niger dosage, initial solution pH and initial Ni(II) concentration on the uptake of Ni(II) by NaOH pretreated biomass of A. niger from aqueous solution were investigated. Batch experiments were carried out in order to model and optimize the biosorption process. The influence of three parameters on the uptake of Ni(II) was described using a response surface methodology (RSM) as well as Langmuir and Freundlich isotherm models. Optimum Ni(II) uptake of 4.82 mg Ni(II) g⁻¹ biomass (70.30%) was achieved at pH 6.25, biomass dosage of 2.98 g L⁻¹ and initial Ni(II) concentration of 30.00 mg L⁻¹ Ni(II). Langmuir and Freundlich were able to describe the biosorption isotherm fairly well. However, prediction of Ni(II) biosorption using Langmuir and Freundlich isotherms was relatively poor in comparison with RSM approaches. The biosorption mechanism was also investigated by using Fourier transfer infrared (FT-IR) analysis of untreated, NaOH pretreated, and Ni(II) loaded A. niger biomass.