Petroleum hydrocarbons and polycyclic aromatic hydrocarbons in the surficial sediments of Xiamen Harbour and Yuan Dan Lake, China

Surficial sediments were sampled from nine stations in Xiamen Harbour and two stations in Yuan Dan Lake during April 2002. Sediment samples were extracted by organic solvents, separated by silica gel column chromatography and analyzed by gas chromatography-mass selective detector (GC-MSD). Selected ion monitoring was at M/Z=57 for petroleum hydrocarbons (PHCs) and individual M/Zs for each of the 15 typical polycyclic aromatic hydrocarbons (PAHs) and nine alkylated PAHs. The results showed that concentrations of PHCs and total PAHs in the sediments of Yuan Dan Lake were 1397 microg g(-1) (dry weight, dw) and 1377 ng g(-1) (dw), respectively. The ranges for PHCs and total PAHs in the sediments from Xiamen Harbour were 133-943 microg g(-1) (dw) and 98-309 ng g(-1) (dw), respectively. Shipping activities, industrial wastewater discharges, fuel oil spillage from ships and vehicles were the main sources of PHCs and PAHs in the Harbour. In addition, the widespread use of coal for industrial processes and domestic consumption accounted for the second largest source of PAHs in the sediments, while atmospheric transport and deposition of PAHs are also important.     

Environmental impacts of tobacco product waste: International and Australian policy responses

The health risks of tobacco consumption are well established, but there is less awareness of the global environmental impacts of smoking. The by-products of the 6.3 trillion cigarettes smoked annually are filters (butts) that contain benzene, nicotine, cadmium, and dozens of other chemicals. It is estimated that between one- and two-thirds of all filters are discarded on roads, pavements, and green spaces. Butt litter as an environmental and public health hazard is a relatively new field of study, but recent research and findings have clear global implications. While this article focuses specifically on the situation in Australia, where cigarette butts are consistently the most littered item identified in national clean-up campaigns, the material reviewed has clear international environmental implications. The article first reviews existing literature on filter composition and toxicology, clean-up costs, regulatory response, and key policy actors. It then describes the scale of the butt litter problem in Australia using existing data, and analyses potential remedies at both the domestic and international levels.     

Responses of the earthworm Eisenia andrei exposed to sublethal aluminium levels in an artificial soil substrate

Industrial discharges of Al are increasingly common. In this study, the activities of three antioxidases, malondialdehyde (MDA) content and changes in coelomocytes were investigated in earthworms (Eisenia andrei) exposed to different concentrations of aluminium chloride (range 0–200 mg Al kg^?1 dry soil) in artificial soils for 32 days. Within the first 16 days of Al exposure, catalase activity was elevated in most treatments, while the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were inhibited in all treatments. After 16 days exposure, SOD and GSH-Px activities returned to normal at lower Al concentrations, but were still inhibited at higher concentrations, hence the inhibition of SOD and GSH-Px showed some exposure-level dependence during the late exposure phase. MDA content was significantly elevated from 16 days after initial exposure. Neutral Red retention time of coelomocytes decreased at the highest exposure concentrations after 32 days, and an increased proportion of cells showing membrane damage was also observed at this time using flow cytometry. We conclude that excessive Al in soils can cause oxidative stress and cell damage in earthworms. Hence, Al accumulation in the environment may present an ecological hazard through suppression of the important functions of earthworms in soil ecosystems.     

Distribution of secondary metabolites in the sponge Oceanapia sp. and its ecological implications

The Micronesian sponge Oceanapia sp. has an unusual growth form that consists of an irregular turnip-shaped base, which is buried in the substrate. One to several fistules, which protrude through the sand, are attached to the base of the sponge. On top of each fistule is a small fragile capitum. We examined whether this conspicuous red-colored sponge was chemically defended and if intraspecimen variation existed in the distribution of secondary metabolites between different parts of the sponge. Furthermore we assessed the deterrent properties of the secondary metabolites to generalist and more specialized fish predators. We also wanted to see if the optimal defense theory holds in the case of a marine invertebrate. According to the theory, organisms evolve and allocate defenses in a way that maximizes individual fitness, assuming that defenses are costly to the fitness of the organisms. We were able to evaluate this hypothesis, since the different sponge parts in Oceanapia sp. were at different risk to damage by predators and had a different value in terms of fitness loss to the sponge (the capitum probably plays a role in asexual propagation). Concentrations of crude organic extract increased from the base to the capitum of the sponge. The major secondary metabolites kuanoniamine C and D also showed a sharp increase from the basal root to the capitum. There was no difference in structural material or ash content between the base and the fistule of the sponge, but fiber and protein content were significantly higher in the fistule. The methanol fraction was highly deterrent in field feeding assays towards generalist reef fish at base concentration. It also deterred feeding by the spongivorous angelfish Pomacanthus imperator in laboratory feeding experiments at the same concentration. The field feeding assays with pure compounds showed that kuanoniamine C and D deterred feeding by natural assemblages of reef fishes at fistule concentrations, confirming their role as defensive agents. The intraspecimen variation of secondary metabolites in Oceanapia sp. supports the optimal defense theory by showing the highest concentrations in those parts of the sponge that are most visible to predators and are likely to be most important for inclusive fitness. Received: 5 May 1999 / Accepted: 16 September 1999     

Genotoxic effects of Ag2S and CdS nanoparticles in blue mussel (Mytilus edulis) haemocytes

The use of functionalised metal sulphide nanoparticles (NPs) for nanoremediation and biomedical application is rapidly increasing, which could lead to significant inputs into the marine environment. The potential impact of some NPs on marine organisms is still poorly understood. In the present paper the genotoxic potential of Ag₂S and CdS NPs on Mytilus edulis haemocytes was assessed. MPEG-SH (thiol-terminated methyl polyethylene glycol), was used as capping agent to avoid NPs agglomeration. TEM analysis showed that the Ag₂S NPs size was 13±7 nm, whereas CdS quantum dots had an average diameter of 4±1 nm. DNA integrity was evaluated by Comet assay following exposure to increasing concentration series (0.01–10 mg/L). Both silver and cadmium NPs showed genotoxic effects at the highest dose. MPEG-SH was also found to exert a weak genotoxic activity, suggesting that at least part of the genotoxic potential of functionalised NPs on mussel cells might be attributable to the capping agent. These results confirm the genotoxic potential of Ag₂S NPs for mussel cells and demonstrated, for the first time, that CdS NPs is genotoxic in a marine organism.     

Guidelines for the Design of Conservation Strategies for the Animals of Venezuela

The geographic distribution of the animals of Venezuela was analyzed as a basis for a series of guidelines to help develop strategies for their conservation. A total of 313 animal taxa is distributed among 24 geographic units, corresponding to the political divisions of the country. Three different criteria were considered in analyzing these data: (1) the number and density of threatened taxa were used to define a ranking system for geographic units; (2) "hotspots" were identified using the distribution of threatened endemics, and (3) a "critical faunas analysis" was used to determine the minimum number of geographic units needed to maximize the number of sampled taxa. The first two criteria emphasize the importance of protecting habitat in the northern portion of the country, where most human intervention has already taken place. But the southern portion of the country is where most of the undisturbed habitat remains. We suggest that the conservation of the animals of Venezuela must follow a mixed strategy, based on two principles: one, aimed mainly at threatened endemics, should focus on the protection of critical habitat north of the Orinoco river, the second, aimed at all threatened animals— particularly high-risk taxa—should focus on assuring the long-term persistence of the pristine habitat in the south.     

Appropriate pCO2 treatments in ocean acidification experiments

Experiments in which organisms are reared in treatments simulating current and future pCO₂ concentrations are critical for ocean acidification (OA) research. The majority of OA exposure experiments use average atmospheric pCO₂ levels as a baseline treatment. We conducted an ecoregion-scale analysis of global carbon chemistry datasets. For many locales, atmospheric pCO₂ levels are not an appropriate characterization of marine carbon chemistry. We argue that atmospheric pCO₂ should be disregarded when setting baseline treatment conditions and experimental design should rely on measurements of carbon chemistry in a study subject’s habitat. As carbon chemistry conditions vary with space and time, we suggest using a range of pCO₂ values as a control rather than a single value. We illustrate this issue with data on the habitat of Euphausia pacifica, which currently lives in waters with a pCO₂ around 900 μatm, a concentration much higher than the current global atmospheric mean.