Pollution characteristics and mixture risk prediction of phenolic environmental estrogens in rivers of the Beijing-Tianjin-Hebei urban agglomeration, China.

Phenolic environmental estrogens (PEEs) are ubiquitous in most rivers worldwide and may cause potential endocrine-disrupting effects in aquatic organisms. Three typical PEEs (bisphenol A, BPA; 4-tert-octylphenol,4-t-OP; and nonylphenol, NP) were investigated in the rivers of the Beijing-Tianjin-Hebei urban agglomeration, which is the most urbanized and industrialized area in North China. The target PEEs were detected in 100% of river water samples, and the concentrations ranged from 23 to 255 ng L-1. The concentrations of NP in most river sections were higher than those of BPA and 4-t-OP. The spatiotemporal variations in PEEs indicated that both domestic and industrial wastewater were main sources of PEEs in river water. In addition, rainfall runoff might be an important source of PEEs in the receiving waters, especially in the wet season. The ecotoxicological risk assessment of individual PEE revealed a moderate to high risk for aquatic organisms at most sampling sites. The mixture risk prediction based on the concentration addition method indicated a potential cumulative risk of PEEs in the study area, highlighting the importance of mixture risk assessment in the aquatic environment.

Estrogens in municipal wastewater and receiving waters in the Beijing-Tianjin-Hebei region, China: Occurrence and risk assessment of mixtures.

The potentially high release of estrogens to surface waters due to high population density and local livestock production in the Beijing-Tianjin-Hebei region may pose adverse effects on reproductive systems of aquatic organisms. This study found that total measured concentrations of estrone (E1), 17ß-estradiol (E2), estriol (E3), 17α-ethinylestradiol (EE2) and diethylstilbestrol (DES) were 468 ± 27 ng/L in treated wastewater and 219 ± 23 ng/L in river waters in this region. E2, E3 and EE2 were the predominant estrogens in river waters. The restriction of DES for human use should have been enforced, however concentrations of DES were relatively high compared to other studies. Haihe and Yongdingxin Rivers delivered approximately 1.8 tonnes of estrogens to the Bohai Bay annually. Concentrations of individual estrogens were significantly higher in river waters in the dry season, however, mass loadings were significantly higher in the wet season. The average E2-equivalent concentrations reached 1.2 ± 0.2 and 0.64 ± 0.08 µg-E2/L following long-term and short-term exposure estimates, respectively, in river waters with an EE2 contribution of over 90 %. This could give rise to high risks to fish. Estrogens in river waters largely derived from human excretion. Field studies on estrogenic effects on fish reproductive systems are required locally considering high estrogen contamination levels.

Spatial and seasonal variations of antibiotics in river waters in the Haihe River Catchment in China and ecotoxicological risk assessment.

Concentrations of widely used antibiotics were predicted to be the highest in the Haihe River Catchment across China previously, potentially resulting in high ecotoxicological risks in this region. As a result of growing usage and regulation of antibiotic use in animals, the pattern of use may have altered temporally for different antibiotics. It is important to monitor the occurrence of antibiotics within different categories for understanding their mass loading to the catchment and the potential ecotoxicological risks involved. This study investigated the seasonal occurrence and spatial variation of 15 antibiotics in the Haihe River Catchment during 2016-2017. The investigated compounds included veterinary antibiotics, human-use antibiotics, and those intended for both human and animal use. Measurements reported from previous studies were compared with the results of this study and indicated that the use of veterinary antibiotics is probably increasing around the catchment. The ∑antibiotics concentration (i.e. the summed concentration of the 15 target antibiotics) ranged from 414 to 1951 ng/L, with an average of 821 ng/L. Discharges from wastewater treatment plants were the main sources of these compounds. The mass loading of antibiotics to the river waters was higher during wet seasons than during dry seasons. The mass fluxes of the antibiotics continuously increased towards the lower reaches of the rivers. The total annual input of the antibiotics from the Haihe River and Yongdingxin River into the Bohai Bay was 5008 kg/yr. Ofloxacin, trimethoprim, leucomycin, anhydro erythromycin and florfenicol were the predominant antibiotics, whilst amoxicillin, anhydro erythromycin, ofloxacin, norfloxacin and enrofloxacin may pose high ecotoxicological risks to the investigated aquatic ecosystem. Several antibiotics selected in this study were reported for the first time in this catchment. This study provides important information for chemical management and indicates that further monitoring is needed on the more harmful and veterinary antibiotics in the catchment.

The occurrence of home and personal care products in the Haihe River catchment and estimation of human exposure.

A sub-catchment of the Haihe River basin goes through the Beijing-Tianjin region with a population of 26 million, therefore, the use and release of home and personal care product ingredients (HPCPs) to the river catchment could be potentially substantial. Many HPCPs have been shown to be toxic to human and animals. So, it is essential to know the exposure level of HPCPs in the river basin. The average concentrations of five preservatives, three disinfectants and an antioxidant were found to be 398, 352 and 77.7 ng L-1, respectively, in the dry season. The chemical concentrations in the effluents of wastewater treatment plants (WWTPs) and untreated wastewater discharge were respectively ca. 1.3-2.2 and 1.6-7.5 times higher than those in river water. The mass flux of ∑HPCPs has been estimated to be 8.7 g/h at the outfall of the Shahe Reservoir and 181 g/h and 214 g/h at the estuary of the Haihe River and Yongdingxin River to Bohai Bay, respectively. The attenuation of ∑HPCPs was over 79% along the Wenyu River. By using the backward method, the estimated average loadings to WWTPs ranged from 0.51 to 2.0 mg/day/cap for the various individual compounds. They were 1-3 orders of magnitude higher than the estimation from the forward calculation for parabens. This indicates the possible underestimation of chemical usage and human exposure levels by the current published studies or the probably additional industrial release to the target catchment. Such a study provides useful information for the development of chemical management approaches and indicates that further research is needed to improve the estimation of HPCPs usage and emissions to aquatic environment.

Estimation of the daily soil/dust (SD) ingestion rate of children from Gansu Province, China via hand-to-mouth contact using tracer elements.

A total of 60 children (31 males and 29 females) between the ages of 3 and 12 years were randomly selected from Lanzhou City in Gansu Province, northwest China. Hand (soil/dust) SD samples from these children were collected using hand wipes. We determined the approximate amounts of hand SD and the concentrations of three tracer soil elements (Ce, Y, and V) in these samples. The approximate amounts of hand SD ranged from 42.28 to 173.76 mg, with a median value of 85.42 mg. In addition, the mean amounts of hand SD estimated using the concentrations of Ce, Y, and V in the samples were 4.63, 3.43, and 3.42 mg, respectively. The amount of hand SD varied greatly among the age groups: primary school children had more hand SD than kindergarten children, males had more hand SD than females, and children from rural areas had more hand SD than those from urban areas. The rates of daily ingestion of hand SD for kindergarten and primary school children were estimated to be 7.73 and 6.61 mg/day, respectively.

[Basic principle and impact factors of soil vapor extraction (SVE) technology for remediation of contaminated soils by volatile and semivolatile organics].

Because soil vapor extraction (SVE) is an effective, economic, and environmentally benign technology to remediate soils contaminated by volatile and semivolatile organics, it has been widely used in the remediation of these soils. The objectives of this paper were to introduce the basic principle of SVE and general steps of constructing SVE engineering, discuss major impact factors on remediation efficiency of SVE technology, and describe three kinds of enhanced SVE technologies. Finally, study and application progress of SVE technologies in China was introduced.

[GIS-based analysis of the land suitability for manure application in the northeastern provinces].

As an important industrial and grain production base of China, livestock and poultry industry have been rapidly developed in the northeastern provinces. With the rapid increasing amount of animal production, how to handle the huge amount of animal manure has become a critical issue for local government. A quantitative analysis based on geographic information system (GIS) combining the biophysical, environmental, social and economic factors was applied to determine the land suitability for manure application in the northeastern provinces. The results show that a farmland area of 211942.7 km2, accounting for 78.9% of the cultivated land in three northeastern provinces, is estimated to be suitable for manure application. The suitable farmlands are mostly distributed in Heilongjiang and Jilin provinces. Proximity to residential area, water body and roads are identified as the primary factors influencing the manure application, while rainfall is the main factor to generate discrepancies in different areas. Furthermore, the future potential capacity for animal production in three provinces was forecasted based on the areas of suitable land and the population of existing livestock production. Among 36 cities of three provinces, the big variation is observed, Siping City is overproducing 1.813 million heads of pig unit at present, but Qiqihaer City still has the potential to rear 11.203 million heads of pig unit. Overall, eastern region of the study area holds the high potential for animal production with a surplus capacity of 2.842 million heads of pig unit, the potential of the typical mountain and forest areas is only 10% of eastern region, however. In contrast, in half of western region (central Liaoning province and central Jilin Province), their animal populations have exceeded the land carrying capacity. Therefore, we strongly suggest a site-specific animal production and manure application guide to achieve a sustainable development of livestock production in the northeastern provinces.

Cadmium in animal production and its potential hazard on Beijing and Fuxin farmlands.

A random sample of pairs of animal feeds and manures were collected from 215 animal barns in Beijing and Fuxin regions of China. The concentrations of Cd in manures and feeds ranged from non-detectable to 129.8 mg/kg dry weight and non-detectable to 31 mg/kg dry weight, respectively. The concentrations of Cd in pig, dairy cow and chicken manures were positively correlated to those in their feeds. About 30% of the manure samples contained Cd concentrations higher than the upper limit for use in farmlands, and pig and chicken manures might be the primary contributors of Cd to farmlands. The farmlands in Beijing and around the Fuxin Downtown areas would exceed the soil quality criteria within several decades according to current manure Cd loading rates. Undoubtedly, more scientific animal production and manure management practices to minimize soil pollution risks are necessary for the two regions.

[Release and transform of lead from the glass of cathode ray tube (CRT) following its entrance in the soil].

The objective of this study was to investigate the release and transform Pb from the CRT glass following its entrance into the soil environment. A long-term incubation of soil mixed with CRT glass particles and sequential selective dissolution technology were used. Results indicated that the addition of CRT glass particle to the soil led to the increase in the total concentration of Pb in the soil from 28.4 mg/kg to 8 634.4 mg/kg. In details,the concentrations of Pb in the soluble and exchangeable form (EXC-Pb) and bound to the carbonate minerals (CARB-Pb) and manganese and iron oxides (RO-Pb) were 0.20-0.98 mg/kg, 20.1-103.6 mg/kg, and 26.7-54.3 mg/kg, respectively. The sum of these three fractions of Pb was 48.6-155.2 mg/kg. In the EXC, CARB, and RO dissolution steps, the concentrations of Pb directly released from the surface of the CRT glass particles were only (0.038 +/- 0.025), (7.55 +/- 3.13), (7.55 +/- 3.13) mg/kg, respectively. Hence, the released Pb from the CRT glass was mostly bound to the carbonate minerals and manganese and iron oxides in the soil. The decrease of pH from 8.0-8.3 to 7.1-7.5 did not significantly affect the chemical forms of Pb in the soil. The release rates of Pb from the CRT glass to the EXC, CARB, and RO forms were 0.15/t, 21.1/t, and 3.8/t mg x (kg x d)(-1), respectively (t is incubation time in unit of d). The CARB-Pb or RO-Pb might transform to EXC-Pb when pH or Eh of soil decreases, thus entrance of CRT glass particles in the soil environment may pose an ecological risk.

[Chemical forms and distribution of phosphorus in the sediment profiles of the Daliaohe River systems].

The Daliaohe river system in China has been seriously affected by long-term intensive industrial, urban and agricultural activities. The objective of this study was to determine the total phosphorus (TP) content and forms of phosphate in the sediments and investigate geochemical relationships between P forms and mineral matrix elements and P bioavailability. Four sediment profiles were taken in the Daliaohe river systems. TP content in the sediment was measured by ICP-OES and chemical forms of phosphate were measured by sequential selective extraction method. Results indicated that TP ranged from 323 to 2619 mg x kg(-1). In the sediments except 25-47 cm depth of sediment profile in the Hun river, the content of Ca bound P (Ca-P) was the highest, with more than 40% of TP. The contents of Fe bound P (Fe-P) and residual P (RES-P) were 15% to 25% of TP, while the contents of reductant soluble P (RS-P) and Al bound P (Al-P) were generally 5% to 10% of TP. However, the content of soluble and loosely bound P (S/L-P) was only less than 0.5% of TP. Huge accumulation of P in the 25-47 cm depth of the sediment profile in the Hun river led to a bigger increase in the contents of Fe-P and Al-P than Ca-P, where Al-P, Fe-P and Ca-P contents were 6.2%-23.4%, 19.6%-34.1% and 14.6%-35.6% of TP, respectively. Correlation analysis showed that sum of Fe-P and RS-P, Ca-P, and RES-P were positively correlated to Fe, Ca, and sediment organic matter (SOM) contents, respectively in the sediments except the 25-47 cm depth of sediment profile in the Hun river. In addition, TP content was positively correlated to Fe and SOM contents. The molar ratios of Fe to TP generally ranged from 20.9 to 33.9, indicating that most of sediments have capability to further retain P. Potential bioavailable P (BAP) including S/L-P, Al-P and Fe-P in the sediments was 85.43 to 1830.5 mg x kg(-1), and this part of phosphorus might pose a potential risk to the eutrophication of the Daliaohe river system and its estuary.

[Contents, contamination and geochemical characteristics of metals in the sediment from Songhua River].

Geochemical behavior of major and trace elements in the sediment of the Songhua River was studied. 39 bottom sediment samples were collected from the Songhua River and total contents of As, Cd, Co, Cr, Cu, Hg, Zn, Ni, Pb, Sb, Sc, V, Mn, Ti, Al, Fe, Mg, Ca, Na and K in these samples were measured. The objectives of this study were to identify the contents and spatial variations of these metals in the sediment, investigate geochemical relationships among the elements, and develop baseline relationships between 9 trace metals and conservative reference element Sc to quantify the contamination of these 9 elements. Results indicated that the concentrations of toxic trace metals, such as As, Cd, Co, Cr, Cu, Hg, Zn, Ni, Pb, and V in the sediment, were 2.7-11.5, 0.05-1.38, 4.8-14.7, 15.9-78.9, 2.4-75.4, 0.01-1.27, 21.8-403.1, 6.2-35.8, 12.6-124.4, and 22.1-108.0 mg/kg, respectively. Due to the input of anthropogenic sources, temporal and spatial variation of Cd, Cu, Hg, Zn, and Pb contents in the sediment was higher than that of major elements. In addition, correlations between these metals and their mineral matrix elements such as Fe, Mg, and Sc were decreased. The baseline relationships between general metal contaminants and Sc were developed, with high correlation coefficients for Co, Cr, Cu, Zn, Ni, Pb, and V and relatively low correlation coefficients for As and Cd. These baseline relationships provide a way to quantitatively evaluate the sediment contamination by these metals. Generally, sediment contamination of the Songhua River by trace metals was less than that of the Zhujiang River and the Changjiang River, and similar to that of the Huanghe River.

[Transport and bioavailability of Cu, Pb, Zn and Ni in surface sediments of Daliao River watersystem].

To understand the transport and bioavailability of heavy metals in the surface sediment of Daliao River system, nine samples of surface sediment were collected. Clay content, pH, and Eh of these sediment samples were measured. Total contents and chemical speciation of Cu, Pb, Zn and Ni in the sediment were determined. In addition, the concentrations of Cu, Pb, Zn and Ni in the pore water of the sediment were determined separately by DGT (diffusive gradient in thin film) method and traditional centrifuge method. The total contents of Cu, Pb, Zn and Ni in the sediment were 16.8-49.2, 12.9-55.8, 38.7-152.8 and 18.1-39.0 mg/kg, respectively. The ratios of DGT measured concentrations c (DGT) to heavy metal concentrations in pore water were lower than 0.5, showing lower replenishment of these metals from solid to the liquid and lower bioavailability of the metals in the sediments. Correlation analysis showed that c (DGT) of Cu was significantly influenced by Cu in the carbonate fraction (r = 0.633, p <0.05), while c (DGT) of Pb was influenced by Pb in the exchangeable fraction (r = 0.617, p <0.05). Ni in the exchangeable, Mn oxides, organic matter (OM) and Fe oxides fractions may contribute to the c (DGT) of Ni (r > 0.650, p <0.05). In addition, pH was also an important factor influencing the release of heavy metals from solid to liquid in sediments.

[Distribution characteristics of organochlorine pesticides in river surface sediments in Song-Liao watershed].

With gas chromatography-electron capture detector (GC-ECD), this paper analyzed 13 kinds of organochlorinae pesticides (OCP) in surface sediments collected from 22 sites of Song-Liao water system. The results showed that the total concentration of OCP varied from 3.06 to 23.24 ng x g(-1) in Daliao River system and from 4.26 to 18.45 ng x g(-1) in Songhuajiang River system. The most dominant OCP pollutant in the sediments in Song-Liao Watershed was HCH, but there existed different pollution tendency in the two subsystems. In Songhuajiang River, there were also relatively high concentrations of DDT. High concentration gamma-HCH was observed among the isomers of HCH in the whole watershed, which exceeded the initial affecting concentration and could potentially do toxic effect on the water creatures.

[Contamination characters of polycyclic aromatic hydrocarbons in Daliao River system of China].

With GC/MS, a quantitative study was made on the polycyclic aromatic hydrocarbons (PAHs) in the surface water and suspended particulates in Daliao River system, with their spatial distribution and sources investigated. The results showed that the total PAHs concentration ranged from 946.1 to 13 448.5 ng x L(-1) in surface water, and from 317.5 to 238 518.7 ng x g in suspended particulates. The PAHs concentration was decreased in the order of Taizi River > Daliao River > Hunhe River. The PAHs in surface water were dominated by 3-5 rings, while those in suspended particulates were dominated by 2 rings. The calculated ratios of selected PAHs suggested that the discharges from municipal, petrochemical and steel industrial wastewater, and the atmospheric fallout might be the important PAHs sources, and the contamination sources of PAHs were the mixture of petrogenic and pyrolytic inputs. In comparing with other river and marine systems in the world, Daliao River system had higher concentrations of PAHs in its surface water and suspended particulates, and thus, presented certain ecological risk.

[High resolution measurement of concentrations and fluxes of heavy metals in pore waters by DGT].

Three sediment cores were collected from the Daliao River system in May 2006. The physico-chemical characteristics and heavy metal contents of sediment cores were analyzed. The vertical profiles of metals in pore water were measured by diffusive gradient in thin films (DGT) and centrifugal methods separately. The sequence of the concentrations of Cd, Co, Cr and Cu in sediment is Cr > Cu > Co > Cd. The concentrations measured by DGT were lower than that measured by centrifugal method. The average ratios of DGT measured concentrations (cDGT) to the concentrations measured by centrifugal method of Cd, Co, Cr and Cu were 0.389, 0.328, 0.863 and 0.403, respectively. This suggested that the release rates of these metals from solid phase to solution followed the sequence of Cr > Cu > Cd > Co. The fluxes of Cd, Co Cr and Cu were 1.12 x 10(-7) - 3.28 x 10(-7) nmol/(cm2 x s), 2.48 x 10(-7) - 10.40 x 10(-7) nmol/(cm2 x s), 8.80 x 10(-6) - 12.65 x 10(-6) nmol/(cm2 x s) and 6.14 x 10(-6) - 13.93 x 10(-6) nmol/(cm2 x s), respectively. The result showed that the release of Cd and Cu was mainly influenced by organic matter (OM), while Fe oxides, Mn oxides and OM were major factors controlling the transfer of Cr. The redox potential may be the major factor influencing the release of Co element.