Polybrominated Diphenyl Ethers in Surface Sediment from Songhua River Basin, Northeast of China

Sixty sediment samples were collected from the main Songhua River in three years. Twelve polybrominated diphenyl ether ( PBDE) congeners ( BDE17, 28, 47, 66, 99, 100, 153, 154, 138, 183, and BDE?209) w...     

Spatial distribution of hexachlorocyclohexanes in agricultural soils in Zhejiang province, China, and correlations with elevation and temperature

Large quantities of hexachlorocyclohexanes (HCHs) were historically applied to soils in Zhejiang, a hilly province of eastern China, yet very limited information is publicly available for the present levels and residue characteristics of HCHs in the region. In this work, concentrations of HCHs and enantiomeric fractions (EFs) of α-isomer were analyzed in 58 agricultural soil samples (0-20 cm) collected in Zhejiang province. On the basis of the ratio of α-HCH/β-HCH and the fact that HCHs were banned in 1983 for agricultural use in China, fresh application of technical HCHs in a large quantity was unlikely in this province. Significant correlation was found between soil concentrations and elevation (R = 0.52, P < 0.001) and temperature (R = -0.55, P < 0.0001), but not between soil concentrations and total technical usage (R = -0.24, P = 0.1), suggesting a typical secondary distribution pattern. The soil residue inventories of HCHs derived from the relationship between concentration and elevation indicated 14.2 tons of HCHs left in agricultural soils in plain areas with the average elevation less than 100 m, and 61.6 tons of HCHs left in mountain soils with the average elevation higher than 100 m. It was also found that EFs of α-HCH were significantly negatively correlated with carbon biomass (C(bio)) in soils. This implies that C(bio) might have important impact on orientation and extent of enantioselective degradation of α-HCH in the region, which is, according to our knowledge, the first report of this kind.     

Concentration and bioaccumulation of dechlorane compounds in coastal environment of northern China

Dechloranes, including Dechlorane Plus (DP), Mirex (Dechlorane), Dechlorane 602 (Dec 602), Dechlorane 603 (Dec 603), and Dechlorane 604 (Dec 604), were determined using GC-MSD for water, sediment and oyster samples collected at 15 sampling sites near the Bohai and Huanghai Sea shore area of northern China in 2008. DP and Mirex were detected in most water, sediment, and oyster samples, which indicated widespread distribution of these two compounds. The mean concentrations in water, sediment and oyster samples, respectively, were 1.8 ng/L, 2.9 ng/g dry weight (dw) and 4.1 ng/g wet weight (ww) for total DP, and 0.29 ng/L, 0.90 ng/g dw, and 2.0 ng/g ww for Mirex. Dec 602 and Dec 603 were not detected in water but in small portions of the sediment and oyster samples, showing a low level of contamination by these two chemicals in the region. Strong and significant correlations were found between total DP and Mirex concentrations in water, sediment and oyster samples, probably suggesting similar local sources of these two chemicals. Dec 604 was not found in any samples. The biota-sediment accumulation factor (BSAF) of DP, Mirex, and Dec 602 declined along with the increase of their logarithm of octanol-water partition coefficients (log Kow), possibly indicating that compounds with lower log Kow (like Mirex and Dec 602) accumulated more readily in biota. The mean fractional abundance of syn-DP (fsyn) was 0.34 in water samples, a value lower than that in Chinese commercial mixture (0.41), while the mean fsyn for surface sediment (0.44) and oyster (0.45) samples were higher than technical values. Enrichment of syn-DP in oyster was in agreement with previously reported findings in Great Lakes fish. Enrichment of syn-DP in marine surface sediments, however, is contrary to data reported for fresh water sediments. To our knowledge this is the first report of Dec 602, Dec 603, and Dec 604 in a marine environment and also the first report of Dechloranes in marine biota.     

Determination of benzotriazole and benzophenone UV filters in sediment and sewage sludge

Benzophenones and benzotriazoles are widely used as ultraviolet (UV) light filters and stabilizers in cosmetics, skin creams, and body lotions and as corrosion inhibitors in building materials, automobile components, and automotive antifreeze cooling systems. Benzophenones and benzotriazoles have been reported to occur in the environment. Some of these UV filters have been reported to possess significant estrogenic activity. Despite this, very few studies have examined their occurrence and profiles in the environment. In this work, we determined five benzophenone-type UV filters and two benzotriazole-type corrosion inhibitors, namely, 2-hydroxy-4-methoxybenzophenone (2OH-4MeO-BP), 2,4-dihydroxybenzophenone (2,4OH-BP), 2,2'-dihydroxy-4-methoxybenzophenone (2,2'OH-4MeO-BP), 2,2',4,4'-tetrahydroxybenzophenone (2,2',4,4'OH-BP), 4-hydroxybenzophenone (4OH-BP), 1H-benzotriazole (1H-BT), and 5-methyl-1H-benzotriazole (5Me-1H-BT), in sediment and sewage sludge samples, using liquid-liquid extraction and liquid chromatography-tandem mass spectrometry (LC-MS/MS). In addition, four benzotriazole-type UV stabilizers, namely, 2-(3-t-butyl-2-hydroxy-5-methylphenyl)-5-chlorobenzotriazole (UV-326), 2,4-di-t-butyl-6-(5-chloro-2H-benzotriazole-2-yl) phenol (UV-327), 2-(2H-benzotriazole-2yl)-4,6-di-t-pentylphenol (UV-328), and 2-(5-t-butyl-2-hydroxyphenyl) benzotriazole (TBHPBT) were determined by gas chromatography (GC)-mass spectrometry (MS). The limits of quantitation (LOQ) were in the ranges of 0.06-0.33 ng g?1 dry weight (dw) and 0.1-1.65 ng g?1 dw for sediment and sludge samples, respectively. Recoveries of target compounds spiked into sample matrices and passed through the entire analytical procedure ranged from 70% to 116% (RSD: 3.32-13.8%) and from 82% to 106% (RSD: 2.89-8.09%) for the compounds analyzed by LC-MS/MS and GC-MS, respectively. The methods were applied to the analysis of sediment samples from the Songhua, Saginaw, and Detroit Rivers; the sum concentrations of target compounds were 3.29-9.93, 5.81-22.5, and 190-389 ng g?1 dw, respectively. Five sludge samples collected from five wastewater treatment plants in northeastern China contained the sum concentrations of target compounds in the range of 104-6370 ng g?1 dw. The concentration of UV-328 in sludge was the highest (mean: 1300 ng g?1 dw) among the target compounds. To our knowledge, this is the first work to report the occurrence of 2OH-4MeO-BP, 2,4OH-BP, 2,2'OH-4MeO-BP, 2,2',4,4'OH-BP, and 4OH-BP in sediment and sludge samples.     

不同温度带多氯联苯土壤残留特征的数值模拟

为了解多氯联苯(PCBs)在不同温度带的环境分布行为及特征,采用ChnGIPERM(Chinese gridded industrial pollu-tants emission and residue model)模型,对PCB同系物单源以相同排放量向大气排放,进行了土壤残留特征的数值模拟,并根据不同温度带选取相应的受体点,进行环境分布行为及特征的分析研究.研究结果表明,PCB同系物在土壤中的残留量与离污染源的距离、理化性质及气象条件有关,随着距离的增大土壤残留浓度降低,气象条件会影响多氯联苯的分布状况.PCB同系物从土壤中的挥发与具有较强温度依存性的蒸汽压有关,低氯取代的PCB同系物因其蒸汽压大于高氯取代的PCB同系物,易于从土壤中挥发而导致其土壤中的残留量迅速降低.[OH]降解速率系数随着氯原子数的增多而降低,从而使长距离迁移过程中,高纬度地区随着氯原子数的增多而使PCBs土壤中的含量增高.     

Levels and isomer profiles of dechlorane plus in Chinese air

The highly chlorinated flame retardant, Dechlorane Plus (DP), was measured in air across 97 Chinese urban and rural sites. DP was detected in 51 of these sites, with a mean air concentration in urban centers (15.6 +/- 15.1 pg m(-3)) approximately 5 times greater than those measured in rural areas (3.5 +/- 5.6 pg m(-3)). These DP levels were likely attributable to local sources rather than trans-boundary influences. Elevated urban levels were measured along the southeastern coast and in south-central China; the highest concentration was observed in the city of Kunming (66 pg m(-3)). Few of the urban samples (7%) and a majority of the rural samples (62%) were below the method detection limit, notably areas in rural central and northeastern China. The mean fractional abundance of the syn-DP isomer (f(syn)) in all samples was 0.33 +/- 0.10, values indistinguishable from that of a commercial mixture (f(syn) = 0.35). This paper represents the first report on DP levels in Chinese air, together with isomeric ratio profiles from urban and rural sites.     

Analysis of polychlorinated biphenyls in concurrently sampled Chinese air and surface soil

Polychlorinated biphenyl (PCB) concentrations were measured in a concurrent air and surface soil sampling program across China. Passive air samples were collected for approximately 3 months from mid-July to mid-October, 2005 using polyurethane foam (PUF) disk type samplers at 97 sites and surface soil samples were collected in a subset of 51 sites in the same year. As expected, the air concentrations (pg m(-3)) were highest at urban sites (mean of 350 +/- 218) followed by rural (230 +/- 180) and background sites (77 +/- 50). The PCB homologue composition was similar across China, with no distinction among site types, and reflected the profile of Chinese transformer oil with a greater proportion of lower molecular weight (LMW) congeners, particularly the tri-PCBs. This differs from the profile in Chinese soil that was shifted toward the higher molecular weight (HMW) congeners and likely attributed to numerous years of deposition and accumulation in this reservoir. The PCB profile in surface soil also reflects an "urban fractionation effect" with preferential deposition of HMW congeners near sources. The profile of PCBs in Chinese air was shown to be different than reported for Europe and for the Great Lakes Area (GLA) in North America. European and GLA air samples show a distinction between urban and rural/V background sites, with urban sites dominated by tetra- and penta-PCBs, whereas rural and background sites are shifted toward LMW congeners. European and GLA samples also exhibit much higher PCB concentrations at urban sites. This may be attributed to the use of PCBs in building materials in European and North American cities. In China, the difference between urban and rural/background sites is less pronounced. Strong soil-air correlations were found for the LMW PCBs at the background and rural sites, and for the HMW PCBs at the urban sites, a strong evidence of the urban fractionation effect. To our knowledge, this is the first national-scale study in China investigating PCBs in both air and surface soil samples.