[Residue Characteristics of Perfluorinated Compounds in the Atmosphere of Shenzhen].

In order to explore the residual characteristics of perfluorinated compounds (PFCs) in the atmosphere of Shenzhen, passive air samplers consisting of polyurethane foam (PUF) disks impregnated with XAD-4 power were deployed at 12 sites in Shenzhen from November 2014 to February 2015. Seven volatile and fifteen ionic PFCs were analyzed. The results indicated that ΣPFCs concentration ranged from 23.7 pg x m(-3) to 157 pg x m(-3) (mean: 79.0 pg x m(-3)), dominated by volatile PFCs, with 8:2 FTOITI, 6:2 FTOH, PFPeA, PFOA being the dominant compounds. The spatial distribution of volatile and ionic PFCs concentrations was the same, displaying the characteristic of "the northwest being higher than the southeast ". Furthermore, the concentrations of 6:2 FTOHs, 8:2 FTOHs, PFPeA, PFHxA and PFOA had positive correlations with PM2.5 and PM10 (P < 0.05, P < 0.01) and were more positively correlated with the levels of PM10 than those of PM2.5.

[Study on Hg2+ distribution and speciation in different tissues of rats].

Mercury is one of the important pollutants that threaten people health greatly in environment. The purpose of this paper was to determine mercury distribution and mercury binding proteins in different tissues of rat fed orally with mercuric chloride by ICP-MS and SEC-UV-ICP-MS. The result showed that liver and kidney induced large amount of metallothioneins that was found to bind to mercury, copper and zinc after mercury intake in stomach and intestines. The metallothioneins induced may be prior to combine the mercury so that it would decrease mercury binding with the other proteins that would disable their normal function.

[Determination of mercury in Chinese medicinal material and biological samples using pyrolysis atomic absorption spectrometry].

In this paper a rapid and simple method using pyrolysis coupled with atomic absorption spectrometry for the analysis of total mercury in Chinese medicinal material and biological samples is presented. No sample digestion was needed and this greatly simplifies the analytical procedure and minimizes potential sources of contamination. Under optimum conditions, the reproducibility of the method was 2.1% for peak area and 9.1% for peak height. The detection limit (3sigma) was 6.3 ng x g(-1), and the recovery was within the range of 95%-105%. Several standard reference materials were analyzed and the results were obtained with satisfaction. The performance of the method was compared with inductively coupled plasma-mass spectrometry (ICP-MS), and excellent agreements were observed between these two methods.

[Pollution fingerprints and sources of perfluorinated compounds in surface soil of different functional areas].

In order to explore the effect of regional functions on the pollution fingerprints and levels of perfluorinated compounds (PFCs), principal components analysis was combined with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and solid phase extraction enrichment in this research to analyze the levels of 14 PFCs species in 76 surface soil samples, which were collected from 4 functional regions, namely parks, communities, crossroads and surroundings of factories, as well as the urban background of Shenzhen. The results showed that regional functions had significant effect on total PFCs (sigma PFCs), which ranked as the following: surroundings of factories (P < 0.001) >> crossroads (P < 0.01) >> communities (P < 0.05) >> parks > urban background. The distribution of PFCs was in the order of medium- (P < 0.05) >> long- > short-chain PFCs in surroundings of factories, communities and crossroads, while in the order of medium- approximately short- (P < 0.05) >> long chain PFCs in crossroads. Over 81% of sigmaPFCs in the surface soil of Shenzhen could be attributed to the three principal components, represented by perfluorooctane sulfonate, perfluorooctane acid and perfluorotridecanoic acid, respectively. PFCs fingerprints were clearly shown in crossroads, as well as in surroundings of electroplating and paint factories.

[Distribution of perfluorinated compounds in surface water of Shenzhen reservoir groups].

In order to study the concentrations of 14 perfluorinated compounds (PFCs) in 25 surface water samples collected from 12 Shenzhen reservoirs in November of 2012 and January of 2013, high performance liquid chromatography-tandem mass spectrometry was combined with solid phase extraction enrichment in this research. The results indicated that perfluorohexane sulfonate and long-chain (C > or = 11) PFCs were below the detection limit in all samples and perfluorooctane acid was the primary species. No significant difference in concentration was found between samples from the center of the reservoir and the outlet. Heavy precipitations diluted PFCs concentrations in surface water, but also led to PFOA input. PFCs concentrations in surface water of the reservoir were mainly affected by water inlet, source environment and geography. Although the water temperature had positive correlations with sigma PFCs concentration, the influence of heavy precipitations was stronger than that of water temperature.

[Influence of tap water treatment on perfluorinated compounds residue in the dissolved phase].

To study the perfluorinated compounds (PFCs) residues through water treatments including flocculation, sedimentation, sand filtration, ozonation with activated carbon and chlorination, as well as the seasonal variation of PFCs in the raw water of waterworks, 13 PFCs species in the dissolved phase of raw water, finished water, as well as the water samples after flocculation, sedimentation, sand filtration, and ozonation with activated carbon filtration were measured by the high performance liquid chromatography-tandem mass spectrometry combined with solid phase extraction. Results indicated that sigma PFCs residue in water was higher in spring and summer than that in fall and winter. The vast majority of PFCs in samples were of short and medium chains (C < or = 10), and perfluorooctane sulfonate was the most typical residue species. Among the five water treatment stages, sedimentation, sand filtration and ozonation with activated carbon filtration can remove PFCs, while flocculation and chlorination significantly raise the levels of short- (C < or = 6) and medium-chain (10 > or = C > or = 7) PFCs, respectively, causing sigma PFCs increase in finished water by 10%-44% compared to raw water. However, the PFCs residues in finished water are still far below their limit values, posing no threat against human health.

[Residue of organic fluorine pollutants in hair and nails collected from Tianjin].

In order to explore the residue and distributions of organic fluorine pollutants in hair and nails, the residue levels of total fluorine (TF), extractable organic fluorine (EOF) and perfluorinated chemicals (PFCs) in hair and nails collected from Tianjin adults were measured by the cyclic neutron activation analysis (CNAA) combined with the high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The results showed that inorganic fluorine (mean: 2.0 mg.kg-1, 4.5 mg.kg-1) was the primary fluorine in TF while EOF(mean: 0.7 mg.kg-1, 1.8 mg.kg-1) was minor. The average amount of identified fluorine (IF) was 0.038 mg.kg-1 in hair and 0.047 mg.kg-1 in nails, accounting or 7.1% (2.6%-16%) and 3.5% (1.1%-11%) of EOF, respectively, which indicated that more than 84% of EOF was unknown. The major residue in hair and nails were medium-and short-chain PFCs,in which perfluorooctane sulfonate, perfluorooctanoic acid and perfluorononanoic acid were the main species. TF, EOF and IF levels in dyed and permed hair were significantly higher than untreated hair (P <0.05), and the concentrations of Sigma PFCs in hair and nails showed no difference between genders. With significantly higher levels of sigma PFCs and PFOS residues than hair (P <0.01), nails could potentially become a more sensitive bioindicator for the exposure level of PFCs in human.

[Residue characteristics and distributions of perfluorinated compounds in surface seawater along Shenzhen coastline].

In order to explore the residue characteristics and distributions of 15 perfluorinated compounds (PFCs) in 18 surface seawater samples along Shenzhen coastline, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) combined with solid phase extraction enrichment was applied in this research. The results indicated that residue level of PFCs in coastal surface seawater samples was significantly affected by human activities. Sigma PFCs residue levels in surface seawater from Shenzhen west coast, which locates below the estuary of Pearl River and Donghao River, are much higher than those from the east coast, which has low development and sparse population (P<0.05). Under natural conditions, sigma PFCs residue levels in coastal surface seawater samples from Shenzhen Bays are higher than those out of bays. The major residue species in surface seawater samples along Shenzhen coast were medium- and short-chain PFCs, including perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorohexanoic acid and perfluoropentanoic acid. Their similar environmental behavior (P<0.05, P<0.01) is likely associated with the production process of PFCs-related products. Furthermore, cluster analysis results show that PFOS (R2 = 0.4092) level can be used as a representative parameter for evaluating PFCs contamination status in surface seawater along Shenzhen coast.

Investigation of zinc binding metallothioneins' polymerization in tris(hydroxymethyl)-aminomethane buffer by coupling of size exclusion chromatography with electrospray ionization mass spectrometry.

Polymerization of metallothioneins (MTs) is one of the commonly encountered puzzles in researching the structure and function of metallothioneins. In this work, a method involving SEC coupled with negative ion electrospray ionization mass spectrometry (ESI-MS) detection has been developed for the study of zinc binding MTs' polymerization in tris(hydroxymethyl)-aminomethane (TRIS) acetate buffer at physiological pH. This hyphenated technique allows separating the different polymeric states of MTs by SEC, followed by on-line identification of the individual MT subisoforms in each polymeric peak by ESI-MS detection. Purified MT subisoforms (MT-2d and MT-2a), MT-2d and MT-2a mixture and rabbit liver MT complexes were investigated in the experiments to confirm the results obtained. From the results, both oxidative polymerization and non-oxidative oligomerization were found. The cystein-dependent oxidation results in the tetrameric peak as shown in the chromatograms of oxidized MT-2d, and stable dimeric and monomeric of MT were detected in this peak by MS. For the dimeric and trimeric peaks, different MT subisoforms were detected. In the five major subisoforms detected in rabbit liver MT complexes, MT-2a and MT-2c exist primarily as trimer, while MT-2e, MT-2d and MT-1a exist mainly as dimer. Our results suggest that in the three kinds of polymers, dimer, trimer and tetramer that were found in samples, the tetramer comes from the oxidation of MT molecular; for the dimer and trimer resulting from cystein independent oligomerization, they are closely associated with the charge of subisoform.

[Determination of andrographolide and dehydroandrographolide in Andrographis paniculata nees materials and related patent medicines by reversed-phase high performance liquid chromatography].

A simple and accurate method for the determination of andrographolide and dehydroandrographolide in andrographis paniculata Nees materials and patent medicines with high performance liquid chromatography (HPLC) has been developed. The two components were extracted from powdered samples by shaking with methanol. The resultant extracts were separated within 15 min on a BECKMAN C18 column (4.6 mm i. d. x 250 mm, 5 microm) and with a gradient elution of acetonitrile-water at a flow rate of 0.5 mL/min. The detection wavelength was 225 nm and the injection volume was 20 microL. In gradient elution program the volume fraction of acetonitrile in mobile phase was as follows: 0 min - 1 min, 40%; 1 min - 5 min, 40% - 50%; 5 min - 15 min, 50% - 70%. Both andrographolide and dehydroandrographolide have good linearity in the range of 10 mg/L to 100 mg/L with the correlation coefficients of 0.997 6 and 0.998 6 respectively. This method has been successfully applied for the analysis of andrographis paniculata Nees materials and related patent medicines.

Investigation of metal-binding metallothioneins in the tissues of rats after oral intake of cinnabar.

The multi-metal-binding MT fractions in rat tissues after oral intake of cinnabar were characterized by hyphenated size-exclusion chromatography (SEC) and inductively coupled plasma mass spectrometry (ICP-MS). With the increase of both the feeding time and dosage of cinnabar the amounts of Hg-binding MT fractions in rat kidney of groups fed cinnabar increased significantly compared with the control group. Meanwhile, more Cu-binding MT were synthesized in the rat kidney, which confirmed the manipulating effect of MT in the homeostasis of Cu for detoxification of nephritic mercury. Although the Hg-binding MT fractions in rat liver of all cinnabar groups were almost independent of cinnabar dosage (2.5-5.0 g kg(-1) bw) and feeding time (2-4 weeks), the amount was much higher than that of the control group. The amounts of Hg-MT in other rat tissues of the cinnabar groups and the control group were compared and their significance is discussed.