Tetrabromobisphenol-A/S and their derivatives in surface particulates from workshop floors of three representative e-waste recycling sites in China.

Surface particulates collected from the workshop floors of three major e-waste recycling sites (Taizhou, Qingyuan, and Guiyu) in China were analyzed for tetrabromobisphenol A/S (TBBPA/S) and their derivatives to investigate the environmental pollution caused by e-waste recycling activities. Mean concentrations of total TBBPA/S analogs in surface particulates were 31,471-116,059 ng/g dry weight (dw). TBBPA, TBBPA-BGE, and TBBPA-BDBPE were the most frequently detected in particulates with average concentration ranges of 17,929-78,406, 5601-15,842, and 5929-21,383 ng/g dw, respectively. Meanwhile, TBBPA, TBBPA-BGE, and TBBPA-BDBPE were the most abundant TBBPA/S analogs, accounting for around 96% of the total. The composition profiles of TBBPA/S analogs differed significantly among three e-waste sites. Similarly, principal component analysis uncovered different pollution patterns among different sites. The discrepancy in the profiles of TBBPA/S analogs largely relied on the e-waste types recycled in different areas. E-waste recycling led to the release of TBBPA/S analogs, and TBBPA/S analogs produced differentiation during migration from source (surface particulates) to nearby soil. More researches are necessary to find a definite relationship between pollution status and e-waste types and study differentiation behavior of TBBPA/S analogs in migration and diffusion from source to environmental medium.

Nontarget and Comprehensive Analyses of Halogenated Organic Additives in Electrical Product Plastics by GC-NCI-Q-Orbitrap-HRMS and Cl/Br-Screening Algorithms.

Halogenated organic additives (HOAs) are used in plastic components of various electrical products, potentially causing detrimental effects on the eco-environment and humans. Besides reported HOAs, many unknown HOAs may be present in electrical product plastics and urgently require identification and characterization. This study performed nontarget analysis and comprehensive characterization of HOAs in three typical electrical product plastics by nontarget analysis using gas chromatography-negative chemical ionization-high-resolution mass spectrometry in association with in-house-developed chlorine/bromine-specific data-processing algorithms. A total of 674 formulas of HOAs were identified in the plastics dismantled from three electrical products, among which 166, 362, and 146 were organochlorines, organobromines, and mix-chlorinated/brominated organic compounds, respectively. The identified HOAs were semiquantified, and the total concentrations of HOAs in individual plastics were 445-1549 ng/g. Organobromines showed the most species and the highest abundances in all of the plastics, of which the abundances accounted for 86.6-98.0% of the total HOAs. Partial HOAs (209 formulas) were tentatively structurally elucidated, which were classified into 13 groups, i.e., halogenated alkyl phenoxyethyls (H-alkyl phenoxyethyls), H-alkylbenzenes, H-benzenes, H-bisphenol A (H-BPAs), H-dioxins, H-diphenyl ethers, H-biphenyls/terphenyls, H-polycyclic aromatic hydrocarbons, H-phenols, H-phenyl esters, H-phenyl-aldehydes/ketones, H-quinones, and an undefined group containing the HOAs such as dechlorane plus and chlordane. H-BPAs were the predominant HOAs in the plastics, showing relatively high concentrations (13-281 ng/g), and tetrabromobisphenol A was the most abundant H-BPA, with the concentrations of 9-196 ng/g. The comprehensive characterization results represent a holistic picture on the species features and abundance distributions of HOAs in electrical product plastics and provide an inventory of crucial HOAs worthy of concern. HOAs may migrate from plastics and release into the environment and are possibly an important source of halogenated organic pollutants in the environment, thus calling for further investigation and proper regulation.

Sex-Specific Bioaccumulation, Maternal Transfer, and Tissue Distribution of Legacy and Emerging Per- and Polyfluoroalkyl Substances in Snakes (Enhydris chinensis) and the Impact of Pregnancy.

The effects of sex and pregnancy on the bioaccumulation and tissue distribution of legacy and emerging per- and polyfluoroalkyl substances (PFASs) in Chinese water snakes were investigated. The bioaccumulation factor of PFASs showed a positive correlation with their protein-water partition coefficients (log KPW), and steric hindrance effects were observed when the molecular volume was > 357 Å3. PFAS levels in females were significantly lower than those in males. The chemical composition of pregnant females was significantly different from that of non-pregnant females and males. The maternal transfer efficiencies of perfluorooctane sulfonic acid were higher than those of other PFASs, and a positive correlation between the maternal transfer potential and log KPW was observed for other PFASs. Tissues with high phospholipid content exhibited higher concentrations of ∑PFASs. Numerous physiological changes occurred in maternal organ systems during pregnancy, leading to the re-distribution of chemicals among different tissues. The change in tissue distribution of PFASs that are easily and not-so-easily maternally transferred was in the opposite direction. The extent of compound transfer from the liver to the egg determined tissue re-distribution during pregnancy.

First Discovery of Iodinated Polyfluoroalkyl Acids by Nontarget Mass-Spectrometric Analysis and Iodine-Specific Screening Algorithm.

Per- and polyfluoroalkyl acids (PFAAs) including polyfluoroalkyl carboxylic acids and polyfluoroalkyl sulfonic acids are a large category of crucial environmental pollutants of global concern. Besides known PFAAs, numerous unknown species may exist in the environment, urgently needing discovery and characterization. This study implemented nontarget analysis for a group of novel PFAA pollutants, viz., iodinated PFAAs (I-PFAAs) in wastewater from a fluorochemical manufacturing park by liquid chromatography-high-resolution mass spectrometry in combination with an iodine-specific data-processing algorithm. The algorithm took into account the diagnostic fragment iodine ion (I-) together with carbon and sulfur isotopologue distributions. In total, 18 I-PFAA formulas involving 21 congeners were identified. Semiquantification was conducted, and the total concentrations of I-PFAAs were 1.9-274.7 µg/L, indicating severe pollution of I-PFAAs in the wastewater. The determined concentrations along with predicted environmental behaviors and toxicities demonstrate that I-PFAAs merit further in-depth investigation. The analytical method including the instrumental analysis and data-processing algorithm can be extended to screening and identification of I-PFAAs in other matrices. Furthermore, the analysis results for the first time provide recognition on the occurrence, distribution features, and pollution status of I-PFAAs in the environment.

Nontarget Analysis and Comprehensive Characterization of Iodinated Polyfluoroalkyl Acids in Wastewater and River Water by LC-HRMS with Cascade Precursor-Ion Exclusions and Algorithmic Approach.

Poly- and perfluoroalkyl acids (PFAAs) are a large family of widespread contaminants of worldwide concern and well-known as "forever chemicals". Direct emission of PFAAs from the fluorochemical industry is a crucial source of PFAA pollutants in the environment. This study implemented nontarget analysis and comprehensive characterization for a category of new PFAA contaminants, i.e., iodinated PFAAs (IPFAAs), in fluorochemical industry wastewater and relevant contaminated river water by liquid chromatography-high-resolution mass spectrometry with a cascade precursor ion exclusion (PIE) strategy and in-house developed data extraction and processing algorithms. A total of 26 IPFAAs (including 2 isomers of an IPFAA) were found and identified with tentative molecular structures. Semiquantification of the IPFAAs was implemented, and the total concentrations of IPFAAs were 0.16-285.52 and 0.15-0.17 µg/L in wastewater and river water, respectively. The high concentrations in association with the predicted ecotoxicities and environmental behaviors demonstrate that these IPFAAs are worthy of more concern and further in-depth research. The cascade PIE strategy along with the data extraction and processing algorithms can be extended to nontarget analysis for other pollutants beyond IPFAAs. The nontarget identification and characterization outcomes provide new understanding on the environmental occurrence and pollution status of IPFAAs from a comprehensive perspective.

Trophic Transfer of Halogenated Organic Pollutants in a Wetland Food Web: Insights from Compound-Specific Nitrogen Isotope of Amino Acids and Food Source Analysis.

A trophic position (TP) model (TPmix model) that simultaneously considered trophic discrimination factor and ßGlu/Phe variations was developed in this study and was first applied to investigate the trophic transfer of halogenated organic pollutants (HOPs) in wetland food webs. The TPmix model characterized the structure of the wetland food web more accurately and significantly improved the reliability of TMF compared to the TPbulk, TPAAs, and TPsimmr models, which were calculated based on the methods of stable nitrogen isotope analysis of bulk, traditional AAs-N-CSIA, and weighted ßGlu/Phe, respectively. Food source analysis revealed three interlocking food webs (kingfisher, crab, and frogs) in this wetland. The highest HOP biomagnification capacities (TMFmix) were found in the kingfisher food web (0.24-82.0), followed by the frog (0.08-34.0) and crab (0.56-11.7) food webs. The parabolic trends of TMFmix across combinations of log KOW in the frog food web were distinct from those of aquatic food webs (kingfisher and crab), which may be related to differences in food web composition and HOP bioaccumulation behaviors between aquatic and terrestrial organisms. This study provides a new tool to accurately study the trophic transfer of contaminants in wetlands and terrestrial food webs with diverse species and complex feeding relationships.

Preliminary Investigation and Imaging Analysis of Early Lung Cancer Screening Among Petroleum Workers in North China.

BACKGROUND: The detection rate of lung nodules has increased significantly among petroleum workers in North China since the low-dose CT (LDCT) screening has been widely carried out. What's more, the number of confirmed early lung cancers is increasing continuously. Therefore, a great deal of concern for the high risk of lung cancer has been shown among petroleum workers. PURPOSE: To improve the screening efficiency and maximize the benefits of the subjects, the current situation of LDCT lung cancer screening should be understood and the imaging characteristics of early lung cancer should be analyzed for petroleum workers in North China. MATERIALS AND METHODS: Firstly, the dynamic changes of LDCT early lung cancer screening for petroleum workers in North China were analyzed in recent years. Then, the survey data of 3121 petroleum workers was compared with that of 1868 non-petroleum workers, which was analyzed. Finally, 91 patients (129 nodular lung cancer) confirmed by pathology were retrospectively analyzed, and the data of which was compared with the clinical features obtained from survey data above. The imaging characteristics and related factors of different subtypes of lung adenocarcinoma were discussed and analyzed. RESULTS: Lung nodules were found in 810 cases (25.95%) out of 3121 petroleum workers; and the surgery was chosen by 42 patients, 38 of whom were confirmed as lung cancer. Compared with the data of screened petroleum workers, there were more older people and more females as well as a higher proportion of people with family malignancy history, and a lower proportion of smoking people in 91 patients with lung cancer. As the pathological grade of tumor nodules increased, the volume and diameter of nodules gradually increased, and the mean density, maximum density and standard deviation of density also increased (p < 0.001). The volume and diameter of nodules were positively correlated with ages (p < 0.05). CONCLUSION: The occurrence of lung adenocarcinoma is closely related to the family history of malignant tumors, and the constituent ratio of young women without a history of smoking increased significantly. At the same time, the quantitative information obtained by using CT images has important value in predicting its pathological subtypes.

Contaminant-related oxidative distress in common kingfisher (Alcedo atthis) breeding at an e-waste site in South China.

The crude electronic waste (e-waste) recycling has caused severe contamination of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in the local environment, begging the question of whether wildlife like birds living at e-waste sites are suffering from adverse effects. We examined several oxidative status markers and their relationships with hepatic concentrations of PCBs and PBDEs in common kingfisher (Alcedo atthis) that inhabit an e-waste site in South China. The results showed that the mean concentrations of ∑PCBs (19100 ng/g) and ∑PBDEs (507 ng/g) in kingfishers from e-waste site were several orders of magnitude higher than those in the species from a reference site. Correspondingly, hepatic concentrations of malondialdehyde (MDA) and reactive oxygen species (ROS) in kingfishers from the e-waste site were significantly higher than those detected in the reference population, suggesting oxidative distress in the birds breeding at the e-waste site. The activities of superoxide dismutase (SOD) and catalase (CAT) in the liver from the exposed group were significantly lower compared with the reference group, while the opposite trend was observed for glutathione peroxidase (GPx). Significantly positive correlations were observed between PCB or PBDE concentrations and the levels of MDA and ROS; while negative correlations were found for enzymatic activities of SOD and CAT. Overall, our results may suggest a potential linkage between exposure to e-waste-derived pollutants and elevated oxidative stress, thereby indicating a potential oxidative stress-related health effects in common kingfisher breeding at the e-waste site.

Karyomapping in preimplantation genetic testing for ß-thalassemia combined with HLA matching: a systematic summary.

PURPOSE: To investigate the validity, accuracy, and clinical outcomes of Karyomapping in preimplantation genetic testing (PGT) for ß-thalassemia combined with human leukocyte antigen (HLA) matching. METHODS: A total of 128 cycles from January 2014 to December 2017 were identified, and 1205 embryos were biopsied. The case group included 88 cycles using Karyomapping for PGT-HLA, compared with 40 cycles using polymerase chain reaction-short tandem repeat (PCR-STR) as the control group. RESULTS: There were significant differences in the HLA matching rate (21.34 vs. 14.37%), the matched transferable embryo rate (9.79 vs. 14.07%), the clinical pregnancy rate (65.08 vs. 41.86%), and the spontaneous miscarriage rate (2.44 vs. 22.22%) between the case and control groups. In the case group, nearly 1/3 (33.37%) of the embryos showed aneuploidy. According to the results of single nucleotide polymorphism (SNP) haplotype analysis, the recombination rates of HBB (hemoglobin subunit beta) and HLA were 11.46% and 5.61% respectively. HLA gene recombination was mostly distributed between HLA-A and HLA-B and the downstream region of HLA-DQB1. In addition, STR analysis could be considered in the case of copy-neutral loss of heterozygosity (LOH) in the region where the HLA gene is located. CONCLUSION: Karyomapping contributes to accurate selection of matched embryos, along with aneuploidy screening. However, STRs assist identification in cases of LOH in the target region.

Characterizing the Influence of Metabolism on the Halogenated Organic Contaminant Biomagnification in Two Artificial Food Chains Using Compound- and Enantiomer-Specific Stable Carbon Isotope Analysis.

Two artificial food chains, food tiger barb-oscar fish and food tiger barb-redtail catfish, were established in the laboratory. The species-specific biotransformation of ortho, para'-dichlorodiphenyltrichloroethane, 12 polychlorinated biphenyl, and five polybrominated diphenyl ether congeners were characterized by measuring the compound- and enantiomer-specific stable carbon isotope composition (δ13C), enantiomeric fraction of the chiral chemicals, and metabolites in the fish. Compound- and enantiomer-specific biotransformations were revealed by the alteration of δ13C and EF in both predator fish species. Significant correlations between the carbon stable isotope signatures and the depuration rates and biomagnification factors (BMF) were observed. Chemicals that exhibited changes in δ13C during the experiment have higher kd and lower BMF values than those with unchanged δ13C. Specifically, the difference between the predicted BMF based on the log Kow and the measured BMF, ΔBMF, was significantly positively and linearly correlated to the change in the δ13C (expressed by Δδ13C/δ13Cinitial, the percentage of Δδ13C: δ13Cending-δ13Cinitial to the initial δ13Cinitial) in both food chains. These results indicated that the impact of metabolism on the bioaccumulation potential of organic contaminants can be predicted by the stable carbon isotope fractionation of chemicals in the fish.

A new method of CT for the cardiac measurement: correlation of computed tomography measured cardiac parameters and pulmonary obstruction index to assess cardiac morphological changes in acute pulmonary embolism patients.

Acute pulmonary embolism (APE) is a serious disease which is life-threatening. Since it is crucial for APE patients to assess the changes of cardiac function safely and timely, the imaging research of cardiac morphology and function is becoming more and more important. The correlation of computed tomography (CT) measured cardiac parameters and pulmonary obstruction index (POI) was analyzed to discuss the morphological changes of the heart of APE patients in order to provide a new method to evaluate cardiac functions accurately and effectively. 118 APE patients confirmed with CT pulmonary angiography (CTPA) were divided into high-risk group (47 cases, POI ≥ 20) and low-risk group (71 cases, POI < 20) according to the Qanadli Score. The left to right diameter (RL) and the anteroposterior diameter (AP) of the cardiac chambers were compared among the high-risk group, the low-risk group, and the normal group (60 cases). The correlation between CT measured cardiac parameters and the POI was analyzed. Except for left ventricular AP and right atrial AP, there were statistically significant differences (P < 0.05) in the RL and AP of the each cardiac cavity, these parameters meant that right hearts were enlarged and the left hearts were decreased in size. The ratio of right/left heart diameter was statistically significant among the three groups, a < b < c (P < 0.05). Moreover, the POI of 118 APE patients was 14.29 ± 9.53, and there was significant linear correlation between CT measured cardiac parameters and the POI (P < 0.05), excluding the left ventricular AP and right atrial AP. The correlation coefficient reached 0.5 or more in terms of the right atrial LR, the right ventricular LR, the ratio of right/left atrial diameter and the ratio of right/left ventricular diameter. With the increasing value of POI, the right atrium and right ventricular of APE patients were enlarged, and the left atrium and left ventricular were decreased in size. These heart changes can be observed by using CTPA, even non-enhanced chest CT.

Tracing the Biotransformation of PCBs and PBDEs in Common Carp (Cyprinus carpio) Using Compound-Specific and Enantiomer-Specific Stable Carbon Isotope Analysis.

Compound-specific and enantiomer-specific carbon isotope composition was investigated in terms of biotransformation of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) as well as atropisomers of chiral PCB congeners in fish by exposing common carp (Cyprinus carpio) to certain PCB and PBDE congeners. The calculated carbon isotope enrichment factors (εC) for PCB 8, 18, and 45 were -1.99, -1.84, and -1.70‰, respectively, providing evidence of the metabolism of these congeners in fish. The stable carbon isotopic compositions of PBDE congeners clearly reflect the debromination of PBDEs in carp. Significant isotopic fractionation was also observed during the debromination process of BDE 153 (εC = -0.86‰). Stereoselective elimination of chiral PCB congeners 45, 91, and 95 was observed, indicating a stereoselective biotransformation process. The similar εC values for E1-PCB 45 (-1.63‰) and E2-PCB 45 (-1.74‰) indicated that both atropisomers were metabolized by the same reaction mechanisms and stereoselection did not occur at carbon bond cleavage. However, the εC values of (+)-PCB 91 (-1.5‰) and (-)-PCB 95 (-0.77‰) were significantly different from those of (-)-PCB 91 and (+)-PCB 95, respectively. In the latter, no significant isotopic fractionations were observed, indicating that the stereoselective elimination of PCB 91 and 95 could be caused by a different reaction mechanism in the two atropisomers.

Number of blastocysts biopsied as a predictive indicator to obtain at least one normal/balanced embryo following preimplantation genetic diagnosis with single nucleotide polymorphism microarray in translocation cases.

PURPOSE: The aim of this study is to investigate the minimum number of blastocysts for biopsy to increase the likelihood of obtaining at least one normal/balanced embryo in preimplantation genetic diagnosis (PGD) for translocation carriers. METHODS: This blinded retrospective study included 55 PGD cycles for Robertsonian translocation (RT) and 181 cycles for reciprocal translocation (rcp) to indicate when only one of the couples carried a translocation. Single-nucleotide polymorphism microarray after trophectoderm biopsy was performed. RESULTS: Reliable results were obtained for 355/379 (93.7 %) biopsied blastocysts in RT group and 986/1053 (93.6 %) in rcp group. Mean numbers of biopsied embryos per patient, normal/balanced embryos per patient, and mean normal/balanced embryo rate per patient were 7.4, 3.1, and 40.7 % in RT group and 8.0, 2.1, and 27.3 %, respectively, in rcp group. In a regression model, three factors significantly affected the number of genetically transferrable embryos: number of biopsied embryos (P = 0.001), basal FSH level (P = 0.040), and maternal age (P = 0.027). ROC analysis with a cutoff of 1.5 was calculated for the number of biopsied embryos required to obtain at least one normal/balanced embryo for RT carriers. For rcp carriers, the cutoff was 3.5. The clinical pregnancy rate per embryo transfer was 44.2 and 42.6 % in RT and rcp groups (P = 0.836). CONCLUSIONS: The minimum numbers of blastocysts to obtain at least one normal/balanced embryo for RT and rcp were 2 and 4 under the conditions of female age < 37 years with a basal FSH level < 11.4 IU/L.

Low aneuploidy rate in early pregnancy loss abortuses from patients with polycystic ovary syndrome.

A prospective cohort study was conducted to determine whether chromosome aneuploidy increases the risk of early spontaneous abortions in patients with polycystic ovary syndrome (PCOS). A total of 1461 patients who conceived after IVF and embryo transfer were followed; 100 patients who had experienced clinical spontaneous abortion were recruited, 32 with PCOS and 68 without PCOS. Before 2013, genetic analysis comprised conventional cultured villus chromosome karyotyping and a multiplex ligation-dependent probe amplification subtelomere assay combined with fluorescence in-situ hybridization; since 2013, array-based comparative genomic hybridization technique combined with chromosome karyotyping has been used. Age, BMI, pregnancy history, gestational age and total gonadotrophin dosage did not differ significantly between the PCOS and non-PCOS groups. In the PCOS group, 28.1% of abortuses demonstrated aneuploidy, which was significantly lower (P = 0.001) than in the non-PCOS group (72.1%). Further statistical analyses controlling for maternal age demonstrated that abortuses of women with PCOS were significantly less (P = 0.001) likely to have chromosome aneuploidy. Embryonic aneuploidy does not play a vital role in early spontaneous abortion in women with PCOS. Maternal factors resulting in endometrial disorders are more likely to be responsible for the increased risk of early spontaneous abortion in patients with PCOS.

[Rapid Propagation in vitro of Dioscorea opposita 'Guangfeng'and Its Stomatal Observation,FCM Analysis of Chromosome Ploidy and ISSR Detection of DNA Mutation].

Objective: To study the rapid propagation in vitro of Dioscorea opposita'Guangfeng', and to observe the stomas of the transplanting plantlets and potted seedlings, to test chromosome ploidy by FCM, and to detect DNA mutation by ISSR,in order to provide the technical basis for the large-scale production of Dioscorea opposita 'Guangfeng' plantlets. Methods: The technique system of Dioscorea opposita 'Guangfeng'rapid propagation in vitro was established and optimized by plant tissue culture method. The parameters of transplanting plantlets and potted seedlings were studied as follows, the stomatal parameters were observed by transparent adhesive tape method, chromosome ploidy were analyzed by FCM, and DNA mutation were detected by ISSR molecular marker. Results: The technique system of Dioscorea opposite 'Guangfeng' rapid propagation in vitro was as follows, slightly woody stem segment with a bud were selected and inoculated onto MS + KT 1 mg / L + NAA 0. 2 mg / L solid culture medium and cultured in the photoperiod of 14 h / d( the temperature was( 25 ± 2) ℃ and light intensity was 1 500 ~ 2 000 Lx) after disinfected for 1 min in 70% alcohol prior to sterilized for 12 min with 0. 1% Hg Cl2,the materials were washed with sterile water for 3 times, respectively. The new bud was cut off when it grew to 2 ~ 3cm and inoculated into MS + KT 2 mg / L + NAA 0. 5 mg / L liquid culture medium and continued to culture in above culture conditions. The whole plant was formed after cultured for about 90 d. The sealing membrane was opened in transplanting, and the plantlets was still placed in above culture conditions and cultured for 2 ~ 3 d, and then the whole plant was taken out, and the culture medium washed off and then transferred into the vessel with shallow liquid MS basic culture medium and domesticated indoor. The acclimated plantlets were taken out and transplanted in the outdoor pots with the sandy soil when the new shoots grew out, and watered one time with tap water in the morning and evening per day, the survival rate reached 100%. The results of stomatal observation, FCM analysis and ISSR detection of transplanting plantlets and potted seedlings showed that the stomatal parameters, chromosome ploidy and DNA mutation of plantlets and potted seedlings had no variation. Conclusion: The results reveal that the establishment and optimization of the technique system of Dioscorea opposita 'Guangfeng' rapid propagation in vitro is feasible, and the regenerated plants do not have genetic variation which can ensure the stability of the genetic.

Chiral polychlorinated biphenyls (PCBs) in bioaccumulation, maternal transfer, and embryo development of chicken.

Polychlorinated biphenyls (PCBs) and enantiomer fractions (EFs) of PCB enantiomers (PCBs 95, 132, 135, and 149) were investigated in soil and chicken feed, chicken (Gallus domesticus) tissues, eggs on 0, 7, and 14 days after the onset of incubation, and newborn chick tissues. The EF values of PCBs 95, 132, and 149 changed significantly from soil to chicken tissues, and the values in the liver exhibited the highest deviation from the racemic ratio, indicating enantiomer-selective metabolism in hens. Congeners, which are highly resistant to degradation, such as PCBs 138, 153, and 180, exhibited the highest maternal transfer potentials when muscle and liver were used to assess the maternal transfer. However, uniform transfer ratios were observed for most of the PCB congeners when visceral fat was used. The EFs of chiral PCBs in eggs either did not match with muscle or with liver or were similar to those in visceral fat. These results indicate that hens mainly mobilized visceral fat for egg formation and PCBs were deposited in eggs by associating with these lipid materials. Further enantiomeric enrichment of PCBs 95, 132, and 149 occurred in the newborn chick tissues. However, an opposite enantioselectivity for PCB 135 in newborn chicks was observed. These results indicate that the potential toxicity of PCB enantiomers to newborn chicks may be different from that of adults.

[Study on Rapid Micropropagation in Vitro Technique of Guangfeng Medicinal Yam (Dioscorea opposita) Plantlets].

OBJECTIVE: In order to provide methodology reference for virus-free and germplasm conservation of Guangfeng medicinal yam (Dioscorea opposita) plantlets, rapid micropropagation in vitro technique of Guangfeng medicinal yam plantlets was studied. METHODS: Using the method of plant tissue culture, single factor test and flow-cytometry, the basic procedure of Guangfeng medicinal yam tissue culture was established and the DNA content of Guangfeng medicinal yam plantlets and its potted seedlings was detected. RESULTS: The best disinfection procedure of stems with a bud of Guangfeng medicinal yam was washed with sterile water for three times after sterilized with 70% alcohol for 20 - 30 s and then washed with sterile water for three times again after sterilized with 0.1% mercuric chloride for 10 - 12 min; The best explants of stems with a bud of Guangfeng medicinal yam was slightly woody and more mature stems witha bud; The best proliferation culture medium of stems with a bud of Guangfeng medicinal yam was MS + 6-BA 2.0 mg/L + NAA 0.1 mg/L; The best rooting culture medium of stems with a bud of Guangfeng medicinal yam was MS + NAA 0.5 mg/L; The best culture method of Guangfeng medicinal yam plantlets was liquid culture; The best transplanting matrix of Guangfeng medicinal yam plantlets was the mixture of paddy clay and fine sand (1: 2) or the mixture of perlite and vermiculite (1: 2); The DNA content between Guangfeng medicinal yam plantlets and its potted seedlings had no significant difference. CONCLUSION: A fast and efficient micropropagation in vitro technological system of stems with a bud of Guangfeng medicinal yam is established, and the flow cytometry detect results also show the genetic stability of Guangfeng medicinal yam plantlets, whose results provide the technical and theoretical basis for the large-scale production of Guangfeng medicinal yam plantlets.

Gastrointestinal absorption, dynamic tissue-specific accumulation, and isomer composition of dechlorane plus and related analogs in common carp by dietary exposure.

Dechlorane plus (DP) is a high-productive volume substance which had been identified as ubiquitous pollutant and has been widely detected in biota. In the present study, common carp (Cyprinus carpio) was exposed to known amounts of commercial DP-25 under laboratory conditions. The gastrointestinal absorption and tissue-specific bioaccumulation of DP and its dechlorinated analogs in common carp were investigated. The higher absorption efficiencies but lower assimilation efficiencies of anti-isomers indicated stereoselective metabolism of anti-isomers in fish. Linear uptake curves were seen in serum and muscle, but the depuration curves for all the four tissues (muscle, serum, liver and gonad) did not follow the first-order kinetics. The liver exhibited a high affinity for anti-isomers during the experiment. Other tissues, such as serum, muscle, and gonad, showed a selective accumulation of syn-DP in the early stages of the experiment, particularly the serum. However, the deviation of fanti between different tissues disappeared at late stages of the experiment, and the fanti values in all tissues were close to that in commercial mixtures. Our results suggest that the bioaccumulation of DP is a complex and multi-factorial process.

Species-specific bioaccumulation of halogenated organic pollutants and their metabolites in fish serum from an e-waste site, South China.

Halogenated organic pollutants (HOPs)-including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenylethers (PBDEs), polybromobiphenyls (PBBs), dechlorane plus (DP), tetrabromobisphenol A (TBBPA), and hexabromocyclododecanes (HBCDs) as well as PCB metabolites (methylsulfone [MeSO2-]) and hydroxylated (OH-) PCBs and OH-PBDEs-were determined in the serum of mud carp and northern snakehead from an electronic-waste (e-waste) site in South China. The average concentrations (mean ± SD) of ΣPCBs, ΣPBDEs, ΣOCPs, ΣPBBs, ΣTBBPA, ΣHBCDs, and ΣDP were 1410 ± 324, 70 ± 20, 3.0 ± 0.4, 2.8 ± 0.8, 1.6 ± 0.4, 1.0 ± 0.2, and 0.3 ± 0.03 ng/g wet weight (ww) in mud carp and 6430 ± 781, 468 ± 49, 22.4 ± 1.1, 7.0 ± 0.6, 2.9 ± 2.3, 5.5 ± 1.1, and 4.6 ± 0.6 ng/g ww in northern snakehead, respectively. MeSO2-PCBs, OH-PCBs, and OH-PBDEs were detected at a total concentration of 0.44 ± 0.03 and 9.7 ± 0.3 ng/g ww in mud carp and northern snakehead, respectively. The congener profiles of PCBs, PBDEs, OH/MeSO2-PCBs, and OH-PBDEs were found to be significantly different between the two fish species, possibly as a result of species-specific bioaccumulation and/or metabolism of the HOPs. Chirality of ten PCB congeners and α-HBCD, as well as the f anti values of DP in the serum samples, supported the species-specific biotransformation of HOPs. Furthermore, the presence of covaried and counter-varied enantiomeric fractions of PCBs between the two fish species indicated species- and congener-specific enantiomer enrichment of PCBs.

A comprehensive assessment of external exposure to persistent halogenated organic pollutants for residents in an e-waste recycling site, South China.

Human skin wipes from 30 participants, air, dust, and food items were collected from a former electronic waste site in South China to provide a comprehensive understanding of residents' exposure to halogenated flame retardants (HFRs) and polychlorinated biphenyls (PCBs). The total concentration of halogenated organic pollutants (HOPs) in the dust, air, food and skin wipes ranged 240-25000 ng/g, 130-2500 pg/m3, 0.08-590 ng/g wet weight, and 69-28000 ng/m2, respectively. Wild fish, vegetables, and air were dominated by PCBs, whereas dust, livestock, and poultry were dominated by HFRs. The HOP concentrations were several orders of magnitude higher in local foodstuffs than in market foodstuffs. The chemical composition on the forehead was remarkably different from that on the hand. The importance of different exposure routes depends on the residents' food choices, except decabromodiphenyl ethane (DBDPE). For residents who consumed a 100-foot diet (mainly egg) and local wild fish, diet ingestion overwhelmed other exposure routes, and PCBs were mainly contributed by fish and HFRs by egg. For residents who consumed market food, the dermal absorption of most PCB congeners and dust ingestion of highly brominated flame retardants were relatively prominent. Inhalation was found to be a crucial route for pentabromoethylbenzene (PBEB).