Modulation of steroidogenesis by coastal waters and sewage effluents of Hong Kong, China, using the H295R assay

BACKGROUND, AIM, AND SCOPE: The presence of a variety of pollutants in the aquatic environment that can potentially interfere with the production of sex steroid hormones in wildlife and humans has been of increasing concern. The aim of the present study was to investigate the effects of extracts from Hong Kong marine waters, and influents and effluents from wastewater treatment plants on steroidogenesis using the H295R cell bioassay. After exposing H295R cells to extracts of water, the expression of four steroidogenic genes and the production of three steroid hormones were measured. MATERIALS AND METHODS: Water samples were collected during the summer of 2005 from 24 coastal marine areas and from the influents and effluents of two major waste water treatment plants (WWTPs) in Hong Kong, China. Samples were extracted by solid phase extraction (SPE). H295R cells were exposed for 48 h to dilutions of these extracts. Modulations of the expression of the steroidogenic genes CYP19, CYP17, 3betaHSD2, and CYP11beta2 were determined by measuring mRNA concentrations by real-time polymerase chain reaction (Q-RT-PCR). Production of the hormones progesterone (P), estradiol (E2), and testosterone (T) was quantified using enzyme linked immunosorbent assays (ELISA). RESULTS: Extracts from samples collected in two fish culture areas inhibited growth and proliferation of H295R cells at concentrations greater or equal to 10(5) L equivalents. The cells were exposed to the equivalent concentration of active substances in 10,000 L of water. Thus, to observe the same level of effect as observed in vitro on aquatic organisms would require a bioaccumulation factor of this same magnitude. None of the other 22 marine samples affected growth of the cells at any dilution tested. Twelve of the marine water samples completely inhibited the expression of CYP19 without affecting E2 production; inhibition of CYP17 expression was observed only in one of the samples while expression of CYP11beta2 was induced as much as five- and ninefold after exposure of cells to extracts from two locations. The expression of the progesterone gene 3betaHSD2 was not affected by any of the samples; only one sample induced approximately fourfold the production of E2. Although more than twofold inductions were observed for P and T production, none of these values were statistically significant to conclude effects on the production of these two hormones. While influents from WWTPs did not affect gene expression, an approximately 30% inhibition in the production of E2 and a 40% increase in P occurred for the exposure with influents from the Sha Tin and Stonecutters WWTPs, respectively. Effluents from WWTPs did not affect the production of any of the studied hormones, but a decrement in the expression of the aldosterone gene CYP11beta2 was observed for the Sha Tin WWTP exposure. No direct correlation could be established between gene expression and hormone production. DISCUSSION: Observed cytotoxicity in the two samples from fish culture areas suggest the presence of toxic compounds; chemical analysis is required for their full identification. Although effluents from WWTPs did not affect hormone production, other types of endocrine activity such as receptor-mediated effects cannot be ruled out. Interactions due to the complexity of the samples and alternative steroidogenic pathways might explain the lack of correlation between gene expression and hormone production results. CONCLUSIONS: Changes observed in gene expression and hormone production suggest the presence in Hong Kong coastal waters of pollutants with endocrine disruption potential and others of significant toxic effects. The aromatase and aldosterone genes seem to be the most affected by the exposures, while E2 and P are the hormones with more significant changes observed. Results also suggest effectiveness in the removing of compounds with endocrine activity by the WWTPs studied, as effluent samples did not significantly affect hormone production. The H295R cell showed to be a valuable toll in the battery required for the analysis of endocrine disrupting activities of complex environmental samples. RECOMMENDATIONS AND PERSPECTIVES: Due to the intrinsic complexity of environmental samples, a combination of analytical tools is required to realistically assess environmental conditions, especially in aquatic systems. In the evaluation of endocrine disrupting activities, the H295R cell bioassay should be used in combination with other genomic, biological, chemical, and hydrological tests to establish viable modes for endocrine disruption and identify compounds responsible for the observed effects.     

Perfluorinated compounds in the Pearl River and Yangtze River of China

A total of 14 perfluorinated compounds (PFCs) were quantified in river water samples collected from tributaries of the Pearl River (Guangzhou Province, south China) and the Yangtze River (central China). Among the PFCs analyzed, perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) were the two compounds with the highest concentrations. PFOS concentrations ranged from 0.90 to 99 ng/l and <0.01–14 ng/l in samples from the Pearl River and Yangtze River, respectively; whereas those for PFOA ranged from 0.85 to 13 ng/l and 2.0–260 ng/l. Lower concentrations were measured for perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), perfluorooctanesulfoamide (PFOSA), perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), perfluorononaoic acid (PFNA), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUnDA). Concentrations of several perfluorocarboxylic acids, including perfluorododecanoic acid (PFDoDA), perfluorotetradecanoic acid (PFTeDA), perfluorohexadecanoic acid (PFHxDA) and perfluorooctadecanoic acid (PFOcDA) were lower than the limits of quantification in all the samples analyzed. The highest concentrations of most PFCs were observed in water samples from the Yangtze River near Shanghai, the major industrial and financial centre in China. In addition, sampling locations in the lower reaches of the Yangtze River with a reduced flow rate might serve as a final sink for contaminants from the upstream river runoffs. Generally, PFOS was the dominant PFC found in samples from the Pearl River, while PFOA was the predominant PFC in water from the Yangtze River. Specifically, a considerable amount of PFBS (22.9–26.1% of total PFC analyzed) was measured in water collected near Nanjing, which indicates the presence of potential sources of PFBS in this part of China. Completely different PFC composition profiles were observed for samples from the Pearl River and the Yangtze River. This indicates the presence of dissimilar sources in these two regions.     

Risk assessment of trace elements in the stomach contents of Indo-Pacific Humpback Dolphins and Finless Porpoises in Hong Kong waters

The potential health risks due to inorganic substances, mainly metals, was evaluated for the two resident marine mammals in Hong Kong, the Indo-Pacific Humpback Dolphin (Sousa chinensis) and the Finless Porpoise (Neophocaena phocaenoides). The stomachs from the carcasses of twelve stranded dolphins and fifteen stranded porpoises were collected and the contents examined. Concentrations of thirteen trace elements (Ag, As, Cd, Co, Cr, Cs, Cu, Hg, Mn, Ni, Se, V and Zn) were determined by inductively coupled plasma mass spectrometer (ICP-MS). An assessment of risks of adverse effects was undertaken using two toxicity guideline values, namely the Reference Dose (RfD), commonly used in human health risk assessment, and the Toxicity Reference Value (TRV), based on terrestrial mammal data. The levels of trace metals in stomach contents of dolphins and porpoises were found to be similar. Risk quotients (RQ) calculated for the trace elements showed that risks to the dolphins and porpoises were generally low and within safe limits using the values based on the TRV, which are less conservative than those based on the RfD values. Using the RfD-based values the risks associated with arsenic, cadmium, chromium, copper, nickel and mercury were comparatively higher. The highest RQ was associated with arsenic, however, most of the arsenic in marine organisms should be in the non-toxic organic form, and thus the calculated risk is likely to be overestimated.     

Fetus in fetu—from prenatal ultrasound and MRI diagnosis to postnatal confirmation

We report a case of fetus in fetu presented as a complex intra-abdominal heterogeneous cystic lesion during ultrasound examination of the fetus at 25 weeks of gestation. Progressive growth of this mass was noted in the prenatal period. Fetal magnetic resonance imaging provided additional information to aid in the prenatal diagnosis. This allows proper counselling for the parents and helps to plan the postnatal management. Surgical excision was carried out in the early neonatal period and the diagnosis of fetus in fetu was confirmed. Copyright © 2007 John Wiley & Sons, Ltd.     

Restorating marine coastal ecosystem health as a new goad for integrated catchment management in Tolo Harbour,Hong Kong,China

The paper demonstrates why it is necessary to take the restoration of marine coastal ecosystem health as a new goal for integrated catchment management, in coastal area of the Tolo Harbour. The present goal of integrated catchment management (ICM) in the Tolo Harbour is to meet with Water Quality Objectives. The performance of an ICM plan, Tolo Harbour Action Plan (THAP), is evaluated by using marine coastal ecosystem health indicators including stress indicators and responses indicators. Since the implementation of THAP in 1988, some significant reduction in pollution loading has been observed - reduction of 83 % of BOD load and 82 % of TN between 1988 and 1999. There has been an improvement in the health state of Tolo Harbour marine coastal ecosystem as evidenced in the trends of the physical, chemical and biological indicators, although some reverse fluctuations in some periods exist. However, this can only be considered as the first sign of the ecosystem health restoration, since ecosystem health co     

A hedonic model of public market transactions for open space protection

A hedonic price function is estimated that illustrates how the price per acre of open space paid by public buyers such as counties or land trusts, is influenced by local demand and supply factors. The empirical regression model is illustrated using 133 public transactions (73% are purchases and 27% are easements) of open space in the Front Range of Colorado. The mean price per acre was $13 635. If a property provides access to water bodies, this feature increases the price per acre by $937, while adjacency of the parcel to existing park or open space adds $11 039 an acre. A 1% increase in county population results in a 0.27% increase in price per acre. Easements cost $6783 less than purchases, a sizeable cost saving. The prediction capability of the hedonic price equation may be an alternative to traditional real estate appraisal techniques when agencies must determine fair market values of prospective open space parcels that vary in attributes from existing ones.     

Application of four watershed acidification models to Batchawana Watershed, Canada

Four watershed acidification models (TMWAM, ETD, ILWAS, and RAINS) are reviewed and a comparison of model performance is presented for a common watershed. The models have been used to simulate the dynamics of water quantity and quality at Batchawana Watershed, Canada, a sub-basin of the Turkey Lakes Watershed. The computed results are compared with observed data for a four-year period (Jan. 1981-Dec. 1984). The models exhibit a significant range in the ability to simulate the daily, monthly and seasonal changes present in the observed data. Monthly watershed outflows and lake chemistry predictions are compared to observed data. pH and ANC are the only two chemical parameters common to all four models. Coefficient of efficiency (E), linear (r) and rank (R) correlation coefficients, and regression slope (s) are used to compare the goodness of fit of the simulated with the observed data. The ILWAS, TMWAM and RAINS models performed very well in predicting the monthly flows, with values of r and R of approximately 0.98. The ETD model also showed strong correlations with linear (r) and rank (R) correlation coefficients of 0.896 and 0.892, respectively. The results of the analyses showed that TMWAM provided the best simulation of pH (E=0.264, r=0.648), which is slightly better than ETD (E=0.240, r=0.549), and much better than ILWAS (E=-2.965, r=0.293), and RAINS (E=-4.004, r=0.473). ETD was found to be superior in predicting ANC (E=0.608, r=0.781) as compared to TMWAM (E=0.340, r=0.598), ILWAS (E=0.275, r=0.442), and RAINS (E=-1.048, r=0.356). The TMWAM model adequately simulated SO4 over the four-year period (E=0.423, r=0.682) but the ETD (E=-0.904, r=0.274), ILWAS (E=-4.314, r=0.488), and RAINS (E=-6.479, r=0.126) models all performed poorer than the benchmark model (mean observed value).     

A comparison of polycyclic aromatic hydrocarbon and petroleum hydrocarbon uptake by mussels (Perna viridis) and semi-permeable membrane devices (SPMDs) in Hong Kong coastal waters

The ability of mussels (Perna viridis) and semi-permeable membrane devices (SPMDs) to accumulate polycyclic aromatic hydrocarbons (PAHs) and petroleum hydrocarbons (PHCs) from five sites in Hong Kong's coastal waters was compared. Mussels consistently had higher levels of contaminants, but their utility was limited at one highly polluted site due to mortality. Mussels and SPMDs ranked sites differently in terms of individual contaminant levels. Although SPMDs overcome many of the disadvantages of using living organisms to measure contaminants in marine waters, they cannot be used as "mimics" due to different PAH and PHC accumulation patterns.     

Risk to breeding success of waterbirds by contaminants in Hong Kong: evidence from trace elements in eggs

Concentrations of 17 trace elements (As, Se, Rb, Sr, Ag, Sb, Cs, Tl, Pb, V, Cr, Mn, Co, Cu, Zn, Cd, and Hg) were determined in eggs of little egrets (Egretta garzetta), black-crowned night herons (Nycticorax nycticorax) and bridled terns (Sterna anaethetus) from northwestern and northeastern coastal areas of Hong Kong. Results indicated significant differences among the three species. Eggs of little egrets and black-crowned night herons appeared to be good bioindicators for monitoring selected elements (As, Pb, Zn Cr, Cu, and V) due to consistent correlations between metal concentrations in eggs and those in coastal marine sediments. Based on limited toxicological information, the predicted no effect concentrations (PNECs) of Hg and Se in the bird eggs were estimated as 0.5 to 1.8 and 0.90 to 1.45 mug g(-1), dry wt., respectively. Hazard quotients (HQs) indicated that Hg and Se might pose some risk to certain waterbirds in Hong Kong.