Spatiotemporal variability of polybrominated diphenyl ether concentration in atmospheric fine particles in Shenzhen, China.

Polybrominated diphenyl ethers (PBDEs) are widely used as flame retardants for various products and have become ubiquitous pollutants in environmental media. However, little is known about PBDE levels in Shenzhen, a manufacturing center of electronic products. This study aimed to investigate spatiotemporal variability of PBDE concentration in atmospheric fine particles (PM2.5) and to estimate the daily inhalation exposure doses for local residents in Shenzhen, China. A total of 36 samples were collected and 8 PBDE compounds (BDE-28, 47, 99, 100, 153, 154, 183 and 209) were analyzed by isotope dilution high-resolution gas chromatograph/high-resolution mass spectrometer (HRGC/HRMS). Mean concentrations of Σ8PBDEs and BDE-209 in PM2.5 in Shenzhen were 33.47 pg/m3 and 24.75 pg/m3, respectively, which were lower than those for other reported cities from China. The mean concentration of Σ8PBDEs was higher in the winter + spring than that in summer + autumn, and both concentrations of BDE-28 and BDE-47 in PM2.5 were significantly higher in winter + spring than those in summer + autumn. Among the 8 congeners, BDE-209 was predominant, accounting for 73.9% of the Σ8PBDEs concentrations. Traffic area, industrial area, residential area and discharge of electronic industries had significant positive influences on PBDE concentrations in PM2.5. Both vegetation area and water area were significantly negatively correlated with PBDE levels in PM2.5. Significantly negative correlation was also found between PBDE concentrations in PM2.5 and the relative humidity. The ranking of estimated inhalation exposure doses of PBDEs via PM2.5 inhalation were toddlers (1.74 pg/kg b.w./day) > children (1.33 pg/kg b.w./day) > adults (1.26 pg/kg b.w./day) > teenagers (0.64 pg/kg b.w./day), and toddlers had a highest risk to expose to PBDEs by PM2.5. To our knowledge, the present study is the first to reveal the spatiotemporal variability of PBDEs in PM2.5 of Shenzhen, China.

Toxaphene levels in retail food from the Pearl River Delta area of South China and an assessment of dietary intake.

Limited literature exists on toxaphene contamination in food worldwide, particularly in mainland China. In this study, three toxaphene congeners, Parlar 26 (B8-1413), Parlar 50 (B9-1679) and Parlar 62 (B9-1025), were analyzed in five different food categories from the Pearl River Delta Area in China using isotope dilution high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS), and toxaphene levels in food were reported and toxaphene dietary intake by local residents estimated. The results showed that fish contained the highest toxaphene level with a median of 12.87 pg/g wet weight (ww), followed by poultry meat, egg products, livestock meat and vegetable, which had median levels of 5.8, 2.2, 1.89 and 0.67 pg/g ww, respectively. Parlar 50 and Parlar 26 were the predominant characteristic congeners in fish, and Parlar 26 was the predominant congener not only in poultry products and eggs, but also in livestock and vegetable. The estimated average daily intake found by local residents was 35.57 pg/kg body weight/day. Overall toxaphene levels and estimated dietary intake in the Pearl River Delta Area of South China are far lower than the European Maximum Residue Limits (EU MRLs), the German MRL for fish, and other international literature data. Therefore, the risk of adverse health effects from dietary intakes of toxaphene for the local residents is not considerable at the current time, but follow-ups are warranted to study dynamic changes of toxaphene in food in this area.

Levels and profiles of polychlorinated dibenzo-p-dioxin and dibenzofurans in raw and treated water from water treatment plants in Shenzhen, China.

Levels and profiles of polychlorinated dibenzo-p-dioxin and dibenzofurans (PCDD/Fs) were analyzed for the first time in raw and treated water from five water treatment plants in Shenzhen, South China. The average PCDD/Fs concentrations were 32.93 pg/L (0.057 pg international toxic equivalent quantity (I-TEQ)/L) and 0.64 pg/L (0.021 pg I-TEQ/L) in raw and treated water, respectively. The removal rate of PCDD/Fs in terms of mass concentration varied from 93.4% to 98.8%, whereas a negative removal rate was observed in one plant in terms of TEQ concentration. The PCDD/Fs concentration in raw water was lower than most of the published data from other countries and regions, and the PCDD/Fs concentration in treated water was below the Maximum Contaminants Level (MCL) of 30 pg/L for dioxin in drinking water set by the US EPA. Historical pentachlorophenol usage, local waste incineration and industrial emissions, as well as surface runoff or even soil erosion, might be the main sources for PCDD/F pollution in water. The daily intake of PCDD/Fs for local residents from drinking water was estimated to be 0.69 fg I-TEQ/kg/day, which is negligible compared with that from food consumption (1.23 pg WHO-TEQ/kg/day) in the local area.

[Levels of polychlorinated dibenzo-p-dioxins and dibenzofurans in airborne fine particulate matter and inhalation risk assessment for local residents of Shenzhen].

OBJECTIVE: To explore the levels and congener profiles of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in airborne fine particulate matter (PM25) in Shenzhen and roughly discuss its correlations between PM25 concentration and meteorological factors. METHODS: The high volume air samplers were used to collect the samples in six sampling sites in respective winter and spring phase and summer and autumn phase. Referring to the US EPA TO-9A for dioxins detection methods, the concentrations of the 17 polychlorinated dibenzo-p-dioxins and dibenzofurans in airborne fine particulate matter were determined by HRGC/HRMS. RESULTS: The total concentrations of PCDD/Fs ranged from 0.32 to 9.35 pg/m3, with average of 2.45 pg/ m3. The TEQ concentrations ranged from 0.006 to 0.388 pg I-TEQ/m3, with average of 0.095 pg I-TEQ/m3. The four abundant congeners were found to be OCDD (36.49%), 1, 2, 3, 4, 6, 7, 8-HpCDF (14.89%), OCDF (13.34%) and 1, 2, 3, 4, 6, 7, 8-HpCDD (10.92%). 2, 3, 4, 7, 8-PeCDF was the dominant contributor to toxicity equivalent (TEQ), accounting for 34.65%. Positive relationship was found between the levels of fine particle-bound PCDD/Fs and PM2.5 concentration (r(s) = 0.794, P = 0.006), whereas no correlation was observed for temperature, humidity and atmospheric pressure. Inhalation exposure to PCDD/Fs were 0. 023 pg I-TEQ/(kg · d) for adult and 0.035 pg I-TEQ/(kg · d) for children during winter and spring and relatively higher than those during summer and autumn (0.014 pg I-TEQ/(kg · d). for adult and 0.021 pg I-TEQ/(kg · d) for children respectively). CONCLUSION: The levels of PCDD/Fs in airborne fine particle-bound samples collected in Shenzhen were lower than those in Hangzhou and Beijing.

[Levels of polychlorinated dibenzo-p-dioxins and dibenzofurans in fish from Shenzhen over the past decade].

OBJECTIVE: To analyze the contamination levels and profiles of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in fish samples in Shenzhen areas of China, and to reveal the status of PCDD/Fs pollution for fish samples in a decade. METHODS: The fish samples including freshwater and saltwater fishes, were collected and analyzed from 2004 to 2013, and PCDD/Fs were detected by isotope dilution HRGC/HRMS using multiple ion detection mode (MID), which was an advanced and authority technique referenced US EPA1613 method. RESULTS: The average concentration of PCDD/Fs in fish was 0.90 pg/(g wet weight), and the average total toxicity equivalency factor (TEQ) calculated on the basis of the toxic equivalency factor (TEF) published by the World Health Organization (WHO) in 2005 was 0.088 pg WHO-TEQ/(g, wet weight). PCDD/Fs levels in fishes varied widely depending on the species. The PCDD/Fs average contamination levels of fish in 10 years did not exceeded the limit standards of European Commission. The evaluation dietary intake of PCDD/Fs from fish for local residents was 4.80 pg WHO-TEQ/(kg · BW · m). CONCLUSION: The PCDD/Fs levels in fish in a decade was less than the maximum limit standards set by European Commission 2011.

[Determination of hexabromocyclododecanes diastereoisomers in human breast milk by HPLC-MS/MS].

OBJECTIVE: A method for the determination of ac, 3 and γ-hexabromocyclododecanes (HBCDs) in human breast milk was developed by HPLC-MS/MS. METHODS: 3 -5 g human breast milk powder was spiked with '3C-HBCDs and then been extracted using Soxhlet extraction. The extract was dried and dissolved in 6ml of cyclohexane/ethyl acetate (1:1 ), then purified by gel permeation chromatography (GPC). The effluent was concentrated with rotary evaporation and then re-dissolved in hexane. 2ml of sulphuric acid was added to remove the fat for further clean-up. After drying under nitrogen, the supernatant was dissolved in 100 µl of methanol and finally determined by HPLC-MS/MS. RESULTS: The linear range for the three diastereoisomers of HBCDs was in 1 - 50 µg/L, with correlation coefficients ranging from 0. 9997 to 0.998. The detection limits of the three diastereoisomers ranged from 0. 12 to 0. 22 µg/L. The recoveries for three spiking levels ranged from 82. 80% to 110. 60% . The intra-day and inter-day relative standard deviations (RSD) were all less than 9. 4%. CONCLUSION: The developed method was simple, convenient and sensitive. It was suitable for the determination of or, P3 and y-HBCDs in breast milk and other matrix in the future.

[Evaluation of nutrient level and its factors of breast milk in Shenzhen City].

OBJECTIVE: To investigate the nutrient level for Fat and Nutrient Elements (Ca, K, Na, Mg, Fe and Zn) in Breast Milk and its factors in Shenzhen, China. Eventually we can evaluate the nutrient study for local infants and provide a more reasonable basis for infants breast-feeding. METHODS: 235 breast milk (1 - 2 months postpartum) samples were collected in three districts of Shenzhen during the year of 2011 to 2013. Fat content was analyzed by Soxlet Extraction System, and elements contents were determined by ICP - OES. RESULTS: The average content of fat was 3.73 g/100 ml. The average concentrations of Ca, K, Na, Mg, Fe and Zn in breast milk from Shenzhen were 296.55, 531.45, 188.96, 28.22, 0.27 and 2.36 mg/L, respectively. CONCLUSION: The average contents of fat and elements of Ca, K in the breast milk from Shenzhen were within the reference ranges provided by the World Health Organization (WHO). However, the levels for element of Fe and Mg were much lower than the reference ranges, and the levels for Na and Zn were relative higher when compared with the standard. No significant difference in six nutrients among three districts in Shenzhen were found, however, the significant difference in each element was found compared with that from other cities or countries. Furthermore Zinc daily intake for local infant reached the level of recommended nutrient intake (RNI), however other nutrients were under the adequate intake level (AI) which was set by Chinese nutrition society (CNS).

[Levels for toxaphene in three categories of animal originated food in Pearl River Delta area].

OBJECTIVE: To explore the present contamination status and profile of toxaphene in fish, chicken and meat samples in Pearl River Delta area. METHODS: Totally 60 independent samples including fish, chicken, meat were collected from Huizhou,Guangzhou,Dongguan,Jiangmen of Pearl River Delta area in Guangdong by purposive sampling from Oct 2010 to Jun 2011. Toxaphene monomer Parlar26, Parlar50 and Parlar62 levels in three various categories of foods were quantitatively and qualitatively analyzed referencing international authoritative standard methods by utilizing isotope dilution high-resolution gas chromatography/high-resolution double-focusing magnetic mass spectrometry (HRGC-HRMS). The levels of pollution and characteristics were compared. RESULTS: The concentration of toxaphene median(M) in fish, chicken and meat were 12.87, 5.8 and 1.89 ng/kg (gross weight) , respectively and the difference was significant(H = 14.29, P = 0.001). The toxaphene level in seafish (M = 32.07 ng/kg) was significantly higher than that in freshwater fish (M = 10.63 ng/kg, Z = -2.52, P = 0.012). The profile analysis showed that Parlar50 and Parlar26 were the predominant characteristic monomers in fish, which contributed about 44% (9.91/22.60, ng/kg) and 39% (8.89/22.60, ng/kg) to total concentration, and Parlar62 and Parlar26 were the two predominant congeners in poultry products, the two congeners accounted for 42% (5.03/11.90, ng/kg) and 38% (4.58/11.90, ng/kg). Furthermore Parlar26 and Parlar62 made up about 57% (3.45/6.08, ng/kg) and 26% (1.58/6.08, ng/kg) of total concentration in livestock meat respectively. CONCLUSION: Toxaphene levels in all tested food samples are far lower than the limited standard stipulated by the European Food Safety Authority (EFSA) in 2002, which was 0.1 mg/kg. The congener characteristic difference in the three categories food indicated that the different enrichment ability in Toxaphene in different animal species.

[Accumulative levels of organochlorine pesticides of HCHs, DDTs in breast milk and risk factors analysis in Shenzhen].

OBJECTIVE: To first investigate the accumulative levels of DDTs and HCHs in human breast milk of primipara in Shenzhen area, analyze influencing factors and assess exposure risk of infant in Shenzhen. METHODS: From April in 2011 to April in 2012, 85 primiparas who have lived in Shenzhen over 3 years after parturition 4 - 6 weeks were recruited, and their breast milk were collected and questionnaires were filled out simultaneously. The samples were extracted five times with hexane, cleaned up by gel permeation chromatograph (GPC) and SPE, and quantified by gas chromatography-election capture detection (GC-ECD). Correlations between DDTs, HCHs and maternal age, weight, dietary, living time as well as infant birth weight and length were also analyzed with the SPSS 13.0 statistical software respectively. RESULTS: Among the several groups of DDTs and HCHs metabolites, p,p'-DDE were detected in total 85 samples and beta-HCH were detected in 58 samples, which accounted for 68.2% of the breast milk. The median levels of sigmaHCHs and sigma DDTs were 2.980 ng/g whole weight (80.200 ng/g fat) and 9.610 ng/g whole weight (268.390 ng/g fat). Both levels of sigmaHCHs and sigmaDDTs in the human milk had a positive association with maternal age among the demographic characteristics of primiparas. Furthermore, levels of sigma HCHs were positively correlated with freshwater fish consumption. However, sigma DDTs levels which were calculated in fat had a positive association only with the amount of poultry meat intake. CONCLUSION: Beta-HCH and p,p'-DDE were detected in human breast milk, and correlated with age and dietary intake. The average estimated daily intakes of HCHs and DDTs by infants are 0.468, 1.842 microg/(kg x BW x d) respectively, lower than acceptable daily intakes (ADI) proposed by the Ministry of Health of China and (the WHO/FAO) Joint Meeting of Pesticide Residues (JMPR). The average levels of HCHs, DDTs in the breast milk in Shenzhen general population are lower than those of Chinese average level.