Growth-selective survival of young jack mackerel Trachurus japonicus during transition from pelagic to demersal habitats in the East China Sea

To examine the growth-selective survival in early life stages of jack mackerel from the East China Sea, we compared growth rates of young fish collected from the surface layer in April with those of survivors collected from the near-bottom layer in May?CJune. We performed this analysis from 3?year classes with different levels of relative abundance: low in 2005, intermediate in 2008 and high in 2009. Growth rates during the larval stage of the original population were slower than the survivors in all survey years, indicating that faster-growing individuals in the surface layer had a higher probability of survival to the near-bottom habitat than slower-growing individuals. Selection intensity, defined as differences in growth rates between the two groups, was higher in year classes with a lower abundance. Hence, growth rates during the early life stages of jack mackerel are considered to be a critical determinant of successful survival to the demersal habitat.     

Percutaneous Exposure Incidents Among Australian Hospital Staff

We investigated all reported percutaneous exposure incidents (PEI) among staff from a large Australian hospital in the 3-year period, 2001-2003. There were a total of 373 PEI, of which 38.9% were needlestick injuries, 32.7% were cutaneous exposures and 28.4% sharps-related injuries. Nurses were the most commonly affected staff members, accounting for 63.5% of the total, followed by doctors (18.8%) and other staff ( 17.7%). Needlestick injuries were responsible for the majority of nurses’ PEI (44.7%). Sharps injuries constituted the major category for doctors (44.3%). Most needlestick injuries (67.6%) were caused by hollow-bore needles, while the majority of cutaneous exposures involved blood or serum (55.8%). Most sharps injures were caused by unknown devices (35.9%) or suture needles (34.9%). Overall, our investigation suggests that PEI is a considerable burden for health care workers in Australia. Further research is now required to determine the relationships, if any, between workers who suffer PEI and those who do not.     

An intercalibration study on organobromine compounds: Results on polybrominated diphenylethers and related dioxin-like compounds

An intercalibration study on organobromine compounds has been conducted to evaluate the accuracy and reliability in the analysis of brominated flame retardants (BFRs) such as polybrominated diphenyl ethers (PBDEs) and their related compounds like polybrominated and monobromo-polychlorinated dibenzodioxins and -furans (PBDDs/DFs, MoBPCDDs/DFs). This paper reports the results for these compounds in 'Mixed Standard Solutions' and 'Air-Dried Sediment'. The relative standard deviations (RSDs) for PBDEs, PBDDs/DFs and MoBPCDDs/DFs in mixed standard solutions ranged from 9% to 24%, 4% to 20% and 8% to 27%, respectively. The results of this study are better than those reported in earlier international interlaboratory studies due to general improvement in analytical methods and an increasing number of available authentic standards, particularly for PBDEs. In the analysis for higher brominated compounds such as octabromodibenzodioxin, the participants were advised to optimize the calibration curves befitting the range of concentrations found in samples because variation of relative response factors was noted. The results for 'Air-Dried Sediment' were also reasonable with RSDs from 10% to 38% for PBDEs, 8% to 38% for PBDDs/DFs and 17% to 36% for MoBPCDDs/DFs. In the sediment sample, possible errors in the sample pretreatment and/or interference by other compounds/impurities were indicated. The concentrations of pentabromodiphenylether, BDE100, varied more than the other PBDE isomers due to its poor separation in some chromatographic conditions. In addition, interference by PBDEs was observed in the analysis for PBDFs. Potential degradation/secondary formulation of PBDEs and PBDFs during the Soxhlet extraction were suggested when copper powder was added into the sediment samples. Inspite of these observations, the results in this study are better than those reported in other interlaboratory studies due to the advice given to participants for improving the results. Compared with the results for PCDDs/DFs (5-23% RSDs) and Co-PCBs (6-24% RSDs), the RSDs for most of the organobromine compounds were high, indicating an immature QA/QC approach for the analysis of PBDEs and related compounds in comparison to common chlorinated dioxins.     

Life-form population responses of a marine planktonic diatom,Chaetoceros pseudocurvisetus,to oligotrophication in regionally upwelled water

Life-form population responses of a centric planktonic diatom,Chaetoceros pseudocurvisetus Mangin, were investigated in summer 1986 and 1988 in the Izu Islands, Japan, in regionally upwelled water where nutrient concentration changed from favorable to unfavorable conditions for active growth and reproduction (oligotrophication). Two types of life form were observed: vegetative cells of healthy and unhealthy looking conditions and resting spores. The observed life-form responses were experimentally evaluated along with a depletion of limiting nutrients. The algal population ceased vegetative growth and initiated resting spore formation with a disappearance of limiting nitrate, and this life-form response seemed to be triggered by the decrease of cellular nitrogen content below a certain level. Since a large amount of silicon was required for the resting spore formation, a part of vegetative cells were unable to form resting spores and formed unhealthy looking vegetative cells under insufficient concentrations of silicic acid. Percentage shares of the resting spores in the population were linearly related to the amounts of available silicic acid. Vegetative cells which did not form resting spores showed greater mortality than resting spores by attack of bacteria and protozoa; however, vegetative cells could respond quickly to possible nutrient replenishment.     

Adsorptive reduction of water hardness by a highly porous and regenerative geopolymer fabricated from coal fly ash waste with low-temperature calcination

Environmental Science and Pollution Research - In this research paper, potassium-activated geopolymer cubes (GeoC) fabricated from waste coal fly ash with low-temperature calcination were...     

Characterization of chlorine and heavy metals for the potential recycling of bottom ash from municipal solid waste incinerators as cement additives

Bottom ash is an inevitable by-product from municipal solid waste (MSW) incineration plants. Recycling it as additives for cement production is a promising disposal method. However, the heavy metals and chlorine are the main limiting factors because of the potential environmental risks and corrosion of cement kilns. Therefore, investigating heavy metal and chlorine characteristics of bottom ash is the significant prerequisite of its reuse in cement industries. In this study, a correlative analysis was conducted to evaluate the effect of the MSW components and collection mode on the heavy metal and chlorine characteristics in bottom ash. The chemical speciation of insoluble chlorine was also investigated by synchrotron X-ray diffraction analysis. The results showed that industrial waste was the main source of heavy metals, especially Cr and Pb, in bottom ash. The higher contents of plastics and kitchen waste lead to the higher chlorine level (0.6 wt.%–0.7 wt.%) of the bottom ash. The insoluble chlorine in the MSW incineration bottom ash existed primarily as AlOCl, which was produced under the high temperature (1250°C) in incinerators.

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Organochlorine and organotin compounds in Caspian seals (Phoca caspica) collected during an unusual mortality event in the Caspian Sea in 2000

Polychlorinated biphenyls (PCBs), organochlorine pesticides and organotin compounds were determined in the blubber and liver of Caspian seals (Phoca caspica) found stranded on the coast of the Caspian Sea during an outbreak of canine distemper virus (CDV) in 2000. Among organochlorines analyzed, DDTs were the most dominant contaminants with concentrations ranging from 6.3 to 470 microg/g on a lipid-weight basis. Caspian seals collected in 2000 during the epizootic had higher concentrations of organochlorines than healthy individuals sampled in 1998. However, the blubber layer was generally thinner in the seals collected in 2000 than those in the previous surveys. Although compositions of organochlorine pesticides in seals suggested that the contamination status in the Caspian Sea is improving, the levels found in Caspian seals in 2000 were comparable to those in other marine mammals that have suffered from epizootics. This implies that the present status of contamination found in Caspian seals poses a risk of immunosuppression. Concentrations of butyltin compounds in livers of seals ranged from 0.49 to 17 ng/g on a wet-weight basis and octyltin compounds were below limit of detection in all the samples analyzed, suggesting less contamination by organotin compounds in the Caspian Sea.