Effects of coal contamination on early life history processes of a reef-building coral, Acropora tenuis.

Successful reproduction and larval dispersal are important for the persistence of marine invertebrate populations, and these early life history processes can be sensitive to marine pollution. Coal is emerging as a contaminant of interest due to the proximity of ports and shipping lanes to coral reefs. To assess the potential hazard of this contaminant, gametes, newly developed embryos, larvae and juveniles of the coral Acropora tenuis were exposed to a range of coal leachate, suspended coal, and coal smothering treatments. Fertilisation was the most sensitive reproductive process tested. Embryo survivorship decreased with increasing suspended coal concentrations and exposure duration, effects on larval settlement varied between treatments, while effects on juvenile survivorship were minimal. Leachate exposures had negligible effects on fertilisation and larval settlement. These results indicate that coral recruitment could be affected by spills that produce plumes of suspended coal particles which interact with gametes and embryos soon after spawning.

Assessment of sediment hydrocarbon contamination from the 2009 Montara oil blow out in the Timor Sea.

In August 2009, a blowout of the Montara H1 well 260 km off the northwest coast of Australia resulted in the uncontrolled release of about 4.7 M L of light crude oil and gaseous hydrocarbons into the Timor Sea. Over the 74 day period of the spill, the oil remained offshore and did not result in shoreline incidents on the Australia mainland. At various times slicks were sighted over a 90,000 km(2) area, forming a layer of oil which was tracked by airplanes and satellites but the slicks typically remained within 35 km of the well head platform and were treated with 183,000 L of dispersants. The shelf area where the spill occurred is shallow (100-200 m) and includes off shore emergent reefs and cays and submerged banks and shoals. This study describes the increased inputs of oil to the system and assesses the environmental impact. Concentrations of hydrocarbon in the sediment at the time of survey were very low (total aromatic hydrocarbons (PAHs) ranged from 0.04 to 31 ng g(-1)) and were orders of magnitude lower than concentrations at which biological effects would be expected.

Novel alkane hydroxylase gene (alkB) diversity in sediments associated with hydrocarbon seeps in the Timor Sea, Australia.

Hydrocarbon seeps provide inputs of petroleum hydrocarbons to widespread areas of the Timor Sea. Alkanes constitute the largest proportion of chemical components found in crude oils, and therefore genes involved in the biodegradation of these compounds may act as bioindicators for this ecosystem's response to seepage. To assess alkane biodegradation potential, the diversity and distribution of alkane hydroxylase (alkB) genes in sediments of the Timor Sea were studied. Deduced AlkB protein sequences derived from clone libraries identified sequences only distantly related to previously identified AlkB sequences, suggesting that the Timor Sea maybe a rich reservoir for novel alkane hydroxylase enzymes. Most sequences clustered with AlkB sequences previously identified from marine Gammaproteobacteria though protein sequence identities averaged only 73% (with a range of 60% to 94% sequence identities). AlkB sequence diversity was lower in deep water (>400 m) samples off the continental slope than in shallow water (<100 m) samples on the continental shelf but not significantly different in response to levels of alkanes. Real-time PCR assays targeting Timor Sea alkB genes were designed and used to quantify alkB gene targets. No correlation was found between gene copy numbers and levels of hydrocarbons measured in sediments using sensitive gas chromatography-mass spectrometry techniques, probably due to the very low levels of hydrocarbons found in most sediment samples. Interestingly, however, copy numbers of alkB genes increased substantially in sediments exposed directly to active seepage even though only low or undetectable concentrations of hydrocarbons were measured in these sediments in complementary geochemical analyses due to efficient biodegradation.

Microbial diversity in sediments associated with a shallow methane seep in the tropical Timor Sea of Australia reveals a novel aerobic methanotroph diversity.

This study examined the diversity of Bacteria, Archaea and in particular aerobic methanotrophs associated with a shallow (84 m) methane seep in the tropical Timor Sea, Australia. Seepage of thermogenic methane was associated with a large carbonate hardground covered in coarse carbonate-rich sediments and various benthic organisms such as solitary corals. The diversity of Bacteria and Archaea was studied by analysis of cloned 16S rRNA genes, while aerobic methanotrophic bacteria were quantified using real-time PCR targeting the alpha-subunit of particulate methane monooxygenase (pmoA) genes and diversity was studied by analysis of cloned pmoA genes. Phylogenetic analysis of bacterial and archaeal 16S rRNA genes revealed diverse and mostly novel phylotypes related to sequences previously recovered from marine sediments. A small number of bacterial 16S rRNA gene sequences were related to aerobic methanotrophs distantly related to the genera Methylococcus and Methylocaldum. Real-time PCR targeting pmoA genes showed that the highest numbers of methanotrophs were present in surface sediments associated with the seep area. Phylogenetic analysis of pmoA sequences revealed that all phylotypes were novel and fell into two large clusters comprised of only marine sequences distantly related to the genera Methylococcus and Methylocaldum that were clearly divergent from terrestrial phylotypes. This study provides evidence for the existence of a novel microbial diversity and diverse aerobic methanotrophs that appear to constitute marine specialized lineages.

The top ten reasons to limit prescription of controlled substances in prisons.

Implementation of a treatment protocol for prescribing stimulant medications in adult prisons where such a protocol and oversight did not previously exist is prudent management, clinically relevant, and appropriate. There are multiple challenges to using controlled substances in correctional settings, many of them a consequence of the very high prevalence of substance use disorders among inmates. This article describes 10 of the reasons to limit the prescription of controlled substances in prison, among them the implications for nursing and correctional security staff and the overwhelming of the already limited psychiatric resources available in most prisons.

Summary results from a pilot study conducted around an oil production platform on the Northwest Shelf of Australia.

The Australian Institute of Marine Science (AIMS) conducted a pilot study around the Harriet A oil production platform on the Northwest Shelf of Australia. We evaluated hepatic ethoxyresorufin-O-deethylase (EROD) activity, fluorescent aromatic compounds (FACs) in bile and immunodetection of CYP1A-like proteins in two Australian tropical fish species, Gold-Spotted Trevally (Carangoides fulvoguttatus) and Bar-Cheeked Coral Trout (Plectropomus maculatus) to assess exposure to petroleum hydrocarbons associated with produced formation water (PFW). Additionally, the incidence of hydrocarbon-degrading bacteria isolated from the liver and bile of all fish captured was examined. Low EROD activity was found in both species, with EROD activity in C. fulvoguttatus showing significant site differences. FACs and CYP1A protein levels in C. fulvoguttatus showed a clear trend in hydrocarbon exposure consistent with hydrocarbon chemistry data: Harriet A>Harriet C>reference site. P. maculatus showed elevated levels of FACs at Harriet A as compared to the reference site and demonstrated detectable levels of CYP1A-like proteins at these two sites. Hydrocarbon-degrading bacteria were found in the liver and bile of both species, yet there was no correlation by sites. Our results demonstrate that C. fulvoguttatus and P. maculatus have potential as indicator species for assessing the effects from exposure to petroleum hydrocarbons. Both FACs and CYP1A are providing warning signs that there is potential for biological effects on fish populations exposed to PFW around the Harriet A production platform.

Testing the ecotoxicology of vegetable versus mineral based lubricating oils: 1. Degradation rates using tropical marine microbes.

Vegetable-derived lubricants (VDL) might be more biodegradable than mineral-derived lubricants (MDL) due to the absence of high molecular weight aromatics, but this remains largely untested in tropical conditions. In this laboratory study, the degradation rates of 2-stroke, 4-stroke and hydraulic VDLs were compared with their MDL counterparts in the presence of mangrove and coral reef microbial communities. While MDLs were comprised largely of unresolved saturated and some aromatic hydrocarbons, their VDL counterparts contained, potentially more degradable, fatty acid methyl esters. Degradation of some VDL was observed by day 7, with the 2-stroke VDL markedly consumed by mangrove microorganisms and the hydraulic VDL degraded by both microorganism communities after this short period. All of the VDL groups were significantly more degraded than the comparable MDLs mineral oil lubricants over 14 days in the presence of either mangrove or coral reef microbial communities. In general the mangrove-sourced microorganisms more efficiently degraded the lubricants than reef-sourced microorganisms.

Testing the ecotoxicology of vegetable versus mineral based lubricating oils: 2. Induction of mixed function oxidase enzymes in barramundi, Lates calcarifer, a tropical fish species.

An increasing number of vegetable-based oils are being developed as environmentally friendly alternatives to petroleum products. However, toxicity towards key tropical marine species has not been investigated. In this study we used laboratory-based biomarker induction experiments to compare the relative stress of a vegetable-based lubricating oil for marine 2-stroke engines with its mineral oil-based counterpart on tropical fish. The sub-lethal stress of 2-stoke outboard lubricating oils towards the fish Lates calcarifer (barramundi) was examined using liver microsomal mixed function oxidase (MFO) induction assays. This study is the first investigation into the use of this key commercial species in tropical North Queensland, Australia in stress assessment of potential hydrocarbon pollution using ethoxyresorufin O-deethylase (EROD) induction. Our results indicated that barramundi provide a wide range of inducible rates of EROD activity in response to relevant organic stressors. The vegetable- and mineral-based lubricants induced significant EROD activity at 1.0 mg kg(-1) and there was no significant difference between the two oil treatments at that concentration. At increasing concentrations of 2 and 3 mg kg(-1), the mineral-based lubricant resulted in slightly higher EROD activity than the vegetable-based lubricant. The EROD activity of control and treated barramundi are found to be within ranges for other species from temperate and tropical environments. These results indicate that vegetable-based lubricants may be less stressful to barramundi than their mineral counterparts at concentrations of lubricant > or =2 mg kg(-1). There is great potential for this species to be used in the biomonitoring of waterways around tropical North Queensland and SE Asia.

The ecotoxicology of vegetable versus mineral based lubricating oils: 3. Coral fertilization and adult corals.

Biodegradable vegetable-derived lubricants (VDL) might be less toxic to marine organisms than mineral-derived oils (MDL) due to the absence of high molecular weight aromatics, but this remains largely untested. In this laboratory study, adult corals and coral gametes were exposed to various concentrations of a two-stroke VDL-1A and a corresponding MDL to determine which lubricant type was more toxic to each life stage. In the fertilization experiment, gametes from the scleractinian coral Acropora microphthalma were exposed to water-accommodated fractions (WAF) of VDL-1A and MDL for four hours. The MDL and VDL-1A WAFs inhibited normal fertilization of the corals at 200 microg l(-1) total hydrocarbon content (THC) and 150 microg l(-1) THC respectively. Disturbance of a stable coral-dinoflagellate symbiosis is regarded as a valid measure of sub-lethal stress in adult corals. The state of the symbiosis in branchlets of adult colonies of Acropora formosa was monitored using indicators such as dinoflagellate expulsion and dark-adapted photosystem II yields of dinoflagellate (using pulse amplitude modulation fluorescence). An effect on symbiosis was measurable following 48 h exposure to the lubricants at concentrations of 190 microg l(-1) and 37 microg l(-1) THC for the MDL and VDL-1A respectively. GC/MS revealed that the main constituent of the VDL-1A WAF was the compound coumarin, added by the manufacturer to improve odour. The fragrance containing coumarin was removed from the lubricant formulation and the toxicity towards adult corals re-examined. The coumarin-free VDL-2 exhibited significantly less toxicity towards the adult corals than all of the other oil types tested, with the only measurable effect being a slight but significant drop in photosynthetic efficiency at 280 microg l(-1).