Nonmetric multidimensional scaling and adverse effects on aquatic biota of polycyclic aromatic hydrocarbons in sediments: A case study of a typical aquaculture wetland, China.

Aquaculture wetlands, particularly those located within urban areas, are fragile ecosystems which are generally heavily impacted by urban and aquaculture activities. However, there are, to date, no reports on adverse effects related to polycyclic aromatic hydrocarbons (PAHs) in sediments from aquaculture wetlands in metropolitan areas. The characterization, sources, and incidence of adverse effects on aquatic biota of PAHs were studied in the riverine and estuarine sediments of the Rongjiang River in an aquaculture wetland in Chaoshan metropolis. The total PAH concentrations varied from 46.0 to 1665.2 ng/g (dry weight), with a mean of 246.4 ng/g, indicating lower concentrations than those of other comparable rivers and estuaries worldwide. High-molecular-weight PAHs were the major PAH species, with fluorene, benzo(b)fluoranthene, and benzo(a)pyrene as the dominant components. These PAHs are likely to be mainly derived from oil and coal/biomass combustion. Probability risk assessment indicated a moderate PAH ecological risk in the Rongjiang River and its estuary (RJE). Accordingly, a comprehensive management plan should be established to ensure sustainable aquaculture wetlands.

Nationwide assessment of persistent halogenated compounds (PHCs) in farmed golden pompano of China.

Persistent halogenated compounds (PHCs) contamination has become a major concern over the world. Here we investigated occurrence, spatial distributions, congener profiles, as well as health risks of PHCs in farmed golden pompano in China using gas chromatography/mass spectrometry (GC/MS). The concentrations of PCBs, PBDEs and OCPs were in the range of 0.78-4.79 ng/g wet weight (ww), not detected (nd)-1.14 ng/g ww and 1.1-38.8 ng/g ww, respectively. Furthermore, ρ,ρ'-DDT, ο,ρ'-DDT and PCB 101 were the dominant PHC contaminants. The estimated daily intakes of PHCs through consumption of golden pompano were up to 12.86 and 131.34 ng/kg body weight/day based on the mean and 95th concentrations determined in golden pompano, respectively. Risk-based analysis indicates that target PHCs in golden pompano would not pose risks to human. Our study presents the first report of a nationwide survey of PHCs contamination in farmed golden pompano in China.

Bioaccessibility and human health implications of heavy metals in different trophic level marine organisms: A case study of the South China Sea.

This study investigated the total concentrations and bioaccessibility of heavy metals in edible tissues and trophic levels of 12 marine organism species in the South China Sea. The results were used to estimate health risks to humans. Of the heavy metals detected, nickel (Ni) was present at the highest concentrations, followed in descending, order by iron (Fe), zinc (Zn), manganese (Mn), chromium (Cr), copper (Cu), cadmium (Cd) and lead (Pb). Cd had the highest percentage bioaccessibility (61.91%). There were no correlations between log-transformed total metal concentrations and trophic level values, nor between log-transformed bioaccessibility metal concentrations and trophic level values. This indicates there is no biomagnification among these trace metals. The carcinogenic risk probabilities for Pb and Cr to urban and rural residents were below the acceptable level (< 1â€¯× 10-4). The target hazard quotient (THQ) value for each metal and the total THQ values for all metals studied indicated no significant risk of non-carcinogenic effects to urban and rural residents from consuming marine organisms from the South China Sea.

Biological risk assessment of heavy metals in sediments and health risk assessment in bivalve mollusks from Kaozhouyang Bay, South China.

The concentrations of heavy metals (Cd, Pb, Cr, Ni, Cu, Zn, Hg and As) in surface sediments and bivalve mollusks in Kaozhouyang Bay were investigated. A biological risk analysis of the sediments indicated that ten sites (about 76.92% of the total number of sites) had a 21% incidence probability of toxicity. A health risk analysis of the bivalve mollusks indicated that Cu and As posed low risks to consumer health. On the basis of the target hazard quotient (THQ), adverse effects may occur based on total THQ (TTHQ). The highest TTHQ was found in the species, Ostrea rivularis, which had the highest capacity for the bioaccumulation (factor > 38) of Cd.

Characterization, sources, and ecological hazards of polycyclic aromatic hydrocarbons in the intertidal sediments of Zhelin Bay, the biggest mariculture area on the eastern Guangdong coast of China.

Distribution characteristics, potential sources, and possible biological hazards of polycyclic aromatic hydrocarbons (PAHs) were examined in intertidal surface sediments of Zhelin Bay, the biggest mariculture base of eastern Guangdong Province, Southern China. The total PAH concentrations ranged from 8.05-51.32 ng/g (dry weight) with an average of 29.23 ng/g, which is beneath the documented concentrations in intertidal sediments gathered from various bays across the globe. The composition of PAHs was distinguished by high molecular weight (HMW, 4-6 rings) PAHs, with phenanthrene (PHE), fluoranthene (FA), and benzo(b)fluoranthene (BbFA) established as predominant components. Principle component analysis along with multivariate linear regression discovered that liquid fossil fuel combustion and coal/wood combustion contribute to 60.23% and 39.77% of PAHs in Zhelin Bay's intertidal sediments, respectively. Overall, surface sediments of Zhelin Bay have an 8% increased incidence of adverse biological effects due to PAH contamination, based on the mean probable effect level quotient.

Elimination kinetics of eugenol in grass carp in a simulated transportation setting.

BACKGROUND: Fish are vulnerable to stress from over-crowding during transportation and eugenol is the most common sedative used to minimize fish injury. The ADI value of 2.5 mg/kg is recommended by the Joint FAO/WHO Expert Committee on Food Additives. The aim of this work was to study the elimination kinetics of eugenol following exposure of grass carp to a eugenol bath in a simulated transportation setting. RESULTS: Grass carp, Ctenopharyngodon idella (120 fish) were exposed for 24 h to a 10 mg/L eugenol bath. Sampling was performed during a 96 h period after the 24 h bath. Eight fish were sampled at each time point and muscle, plasma and liver concentrations of the drug were determined by ultra-performance liquid chromatography-tandem mass spectrometry. The concentration-time data of eugenol in each tissue were analyzed using non-compartmental methods. The peak concentrations (Cmax) in plasma, muscle and liver were 7.68, 5.30 and 24.63 mg/kg and the elimination half-lives (t1/2ß) were 19.79, 10.27 and 55.28 h, respectively. The clearance (CL) values were 0.10, 0.44 and 0.04 L/h/kg and the areas under the concentration-time curve (AUC0-96h) were 91.54, 22.44, and 214.12 mg·h/L in plasma, muscle and liver, respectively. After a eugenol exposure bath, drug concentrations in muscle tissue of grass carp were below 1 mg/kg at 8 h and 0.1 mg/kg at 24 h. CONCLUSIONS: The drug concentrations in muscle tissue at 8 h were lower than the recommended ADI value.

Polycyclic Aromatic Hydrocarbons (PAHs) in Exposed-Lawn Soils from 28 Urban Parks in the Megacity Guangzhou: Occurrence, Sources, and Human Health Implications.

Polycyclic aromatic hydrocarbons (PAHs) in urban soils may pose a serious threat to human health via oral ingestion, dermal absorption, and particulate inhalation, especially in public parks and playgrounds, with children and senior citizens showing the highest susceptibility. Several studies have been undertaken identifying PAHs in urban soils, but no studies to date have assessed PAHs in urban parks, in particular in exposed-lawn soils. In recent decades, unprecedented rates of urbanization and industrialization in China have resulted in significant levels of urban environmental pollution. However, concentrations, sources, and the health risk associated with PAH exposure via urban park lawn soils in China remain unknown. The concentrations, sources, and health risk of exposure to 16 PAHs in surface-exposed lawn soils were studied in 28 urban parks in Guangzhou. Concentrations of Σ16PAHs ranged from 76.44 to 890.85 ng/g with a mean of 286.11 ng/g. PAH composition was mostly characterized by 2- and 4-ring PAHs in most sampling parks; Nap, Flua, Pyr, Phe, and Chr were the dominant constituents. Principle component analysis coupled with multivariate linear regression indicated that vehicular and coal combustion emissions contributed to 50.53 and 49.46% of PAHs in Guangzhou's urban park soils, respectively. Total cancer risk (TCR) analysis found that 22 parks (accounting for 78.57% total parks) designed for children's use and general-use park areas presented a potentially high risk (>1 × 10-4) for all users.

Polycyclic aromatic hydrocarbons (PAHs) in wild marine organisms from South China Sea: Occurrence, sources, and human health implications.

Concentrations of 16 US EPA priority polycyclic aromatic hydrocarbons (PAHs) were measured in 15 marine wild organism species from South China Sea. The concentration (dry weight) of 16 PAHs ranged from 94.88 to 557.87ng/g, with a mean of 289.86ng/g. The concentrations of BaP in marine species were no detectable. The composition of PAHs was characterized by the 2- and 3-ring PAHs in marine species, and NA, PHE and FA were the dominant constituents. PAHs isomeric ratios indicated PAHs mainly originated from grass, wood and coal combustion, and petroleum. The human health risk assessment based on the excess cancer risk (ECR) suggested the probability of PAHs posing carcinogenic risk to human beings with consumption of marine organisms were negligible (probability<1×10-6).

Polycyclic aromatic hydrocarbons (PAHs) in sediments of Zhelin Bay, the largest mariculture base on the eastern Guangdong coast, South China: Characterization and risk implications.

We investigated distribution, sources, and potential risks of polycyclic aromatic hydrocarbons (PAHs) in the surface sediments from the largest mariculture base in the eastern part of the province of Guangdong in southern China. Total concentrations of ∑PAHs were 29.38-815.46ng/g (dry weight), with a mean of 421.48ng/g. The composition of PAHs was characterized by an abundance of low molecular weight PAHs (2-3 benzenoid ring), and Phenanthrene (PHE), Anthracene (AN) and Fluoranthene (FA) were the predominant constituents. PAHs in this area appear to have mainly originated from petroleum sources and the combustion of grass, wood, and coal. PAHs in surface sediments of Zhelin Bay had a 9% incidence of causing adverse biological effects on aquatic organisms, according to the mean effects range-median quotient.

Spatial-temporal trend and health implications of polycyclic aromatic hydrocarbons (PAHs) in resident oysters, South China Sea: A case study of Eastern Guangdong coast.

Spatial and temporal distributions of polycyclic aromatic hydrocarbons (PAHs) were investigated in Eastern Guangdong coast, China. Total PAH concentrations in oysters ranged from 231 to 1178ng/g with a mean concentration of 622ng/g dry weight. Compared with other bays and estuaries, PAH levels in oysters were moderate. Spatial distribution of PAHs was site specific, with relatively high PAH concentrations observed in Zhelin Bay and Kaozhouyang Bay. Based on the Spearman test analysis, only PAH concentration in oysters from Jiazi Harbor showed a significant increasing trend (P<0.05). Three-ring PAHs were the most abundant, accounting for 54.2%-88.4% of total PAHs. Diagnostic ratios suggested that PAHs were derived mainly from petroleum origin. BaP and ∑4PAH concentrations were well within the European Union limits (5ng/g and 30ng/g wet weight, respectively). The incremental lifetime cancer risks (ILCR) for PAHs were <10(-5), indicating that the adverse health risks associated with oyster consumption in this area were minimal.

Polycyclic aromatic hydrocarbons in surface sediments and marine organisms from the Daya Bay, South China.

Polycyclic aromatic hydrocarbons (PAHs) were investigated in the marine ecosystem of the Daya Bay, South China. The PAH concentrations ranged from 340 to 710 ng/g dry weight in the sediments and from 110 to 520 ng/g wet weight in marine organisms, respectively. The dominant compounds were three- and four-ring PAHs in the sediments (53%-89%) and two- and three-ring PAHs in the marine species (67%-94%), respectively. PAHs mainly originated from both pyrolytic and petrogenic sources. Comparison with the effects-based sediment quality guideline values suggested that the ecological risk caused by the total PAHs was relatively low (less than 25% incidence of adverse effects) in the sedimentary environment. The median cancer risk level via seafood consumption (1.6 × 10(-5) for urban residents and 1.2 × 10(-5) for rural residents, respectively) was slightly higher than the maximum admissible level (10(-5)) set by US EPA, but lower than the priority risk level (10(-4)).

Speciation and risk of heavy metals in sediments and human health implications of heavy metals in edible nekton in Beibu Gulf, China: A case study of Qinzhou Bay.

We investigated the total concentrations of heavy metals in surface sediments and nekton, along with sediment metal chemical partitioning in Qinzhou Bay of the Beibu Gulf. Cd was preferentially associated with the acid-soluble fraction and Pb mainly with the reducible fraction, whereas a major portion of Cr, Ni, Cu, and Zn was strongly associated with the residual fractions. A principal component analysis (PCA) in sediment metal speciation revealed three groupings (Cd; Pb; Cr, Ni, Cu, and Zn) that mainly resulted from different distributions of the metals in the various fractions. The Cr concentrations in nekton species were higher than maximum Cr concentrations permitted by the Chinese National Standard (GB 2762-2012). Taking as a whole, surface sediments of Qinzhou Bay had a 21% incidence calculation of adverse biological effects, based on the mean probable-effects-levels quotient. A human health risk assessment indicated no significant adverse health effects from consumption of nekton.

[Residues and risk assessment of polycyclic aromatic hydrocarbons in the surface sediments and marine organisms from Dapeng Bay, Shenzhen].

In order to assess contamination by polycyclic aromatic hydrocarbons (PAHs), surface sediments and marine organism samples of fish, shrimp and shellfish were collected from the Dapeng Bay, Shenzhen in October 2011. Concentrations fof sixteen priority PAHs were determined by gas chromatography and mass spectrometry (GC-MS). The total concentrations of PAHs (Sigma PAHs ) ranged from 216. 56 ng.g-1 to 1 314. 92 ng.g-1 dry weight in sediment samples and from 70. 88 ng.g-1 to 251.90 ng.g-1 wet weight in biological samples, respectively. The mean concentration was the highest in fish (171.52 ng.g-1 ), followed by mussel (134.75 ng.g-1) and shrimp (123.35 ng.g-1) in the studied marine organisms. Compared with those in other water bodies around the world, PAHs pollution in the studied area was at medium level. The dominant fraction in the surface sediments was the 4-ring PAHs. Identification of PAH sources suggested that PAHs in Dapeng Bay were likely originated from both pyrolytic and petrogenic sources. The most abundant PAHs were 3-ring PAHs in the tissues of organisms, which may be governed by their feeding behaviors, habitats, and bioavailability of PAHs. Ecological risk assessment indicated that PAHs in surface sediments might have adverse impacts on local ecosystem. Health risk analysis revealed that the potency equivalent concentrations of BaP to the total PAHs in marine organisms from Dapeng Bay were relatively high and may cause some concerns on human health by consumption.

Levels, composition profiles and sources of polycyclic aromatic hydrocarbons in surface sediments from Nan'ao Island, a representative mariculture base in South China.

Levels, composition profiles and sources of 16 polycyclic aromatic hydrocarbons (PAHs) in surface sediments from Nan'ao Island, one of the largest mariculture bases in South China were investigated. The total PAHs concentrations ranged from 265.49 to 951.27 ng/g (dry weight) with a mean of 515.90 ng/g, and seven possible carcinogenic PAHs accounted for 76.94% of total PAHs. Among various mariculture sections, the highest PAHs level was found in the large seaweed culture; while the lowest concentration was detected in the abandoned culture. The composition of PAHs was characterized by low molecular weight PAHs, and Phe Ant and Pyr were the dominant constituent. PAHs may be mainly originated from petroleum and combustion of biomass and coal. Risk assessments suggested that the probability of adverse effect was lower than 25% and PAHs exposure was moderately carcinogenic.

[The progress in speciation analysis of trace elements by atomic spectrometry].

The main purpose of the present work is to review the different non-chromatographic methods for the speciation analysis of trace elements in geological, environmental, biological and medical areas. In this paper, the sample processing methods in speciation analysis were summarized, and the main strategies for non-chromatographic technique were evaluated. The basic principles of the liquid extractions proposed in the published literatures recently and their advantages and disadvantages were discussed, such as conventional solvent extraction, cloud point extraction, single droplet microextraction, and dispersive liquid-liquid microextraction. Solid phase extraction, as a non-chromatographic technique for speciation analysis, can be used in batch or in flow detection, and especially suitable for the online connection to atomic spectrometric detector. The developments and applications of sorbent materials filled in the columns of solid phase extraction were reviewed. The sorbents include chelating resins, nanometer materials, molecular and ion imprinted materials, and bio-sorbents. Other techniques, e. g. hydride generation technique and coprecipitation, were also reviewed together with their main applications.