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A letter to the editor is presented in response to the article "A perspective on the toxicity of low concentrations of petroleum-derived polycyclic aromatic hydrocarbons to early life stages of herring and salmon" by D. S. Page and colleagues in the 2012 issue.

Habitat damage resulting from oil contamination is underestimated by acute toxicity assays. Nearshore substrates oiled by spills may become persistent pollution sources of toxic polycyclic aromatic hydrocarbons (PAH). Recent findings resulting from research following the Exxon Valdez oil spill include: (1) PAHs are released from oil films and droplets at progressively slower rates with an increasing molecular weight, leading to greater persistence of larger PAHs; (2) eggs from demersally-spawning fish species accumulate dissolved PAHs released from oiled substrates, even when the oil is heavily weathered; and (3) PAHs accumulated by embryos from aqueous concentrations of < 1 µg/L can lead to adverse sequelae appearing at random over the lifespan of an exposed cohort, probably as a result of damage during early embryogenesis. Polycyclic Aromatic Hydrocarbons (PAH) can be a slow-acting poison, and toxic effects may not manifest until long after exposure. These considerations have important policy implications regarding protection of fish natal and rearing habitats. [ABSTRACT FROM AUTHOR]

Assessment of environmental damage following accidental oil spills requires reliable oil identification methods. Results from hydrocarbon analyses of environmental samples are often difficult to interpret, because of the changes in oil composition (or weathering) that follows release into the environment, and because of confounding by hydrocarbons from other sources. To a first-order approximation, weathering proceeds according to simple first-order loss-rate (FOLR) kinetics for polycyclic aromatic hydrocarbons (PAH) based on molecular size. This relationship between relative weathering rate and molecular size can be exploited to infer the initial PAH composition of spilled oils, and this information can be combined with results for weathering-invariant analytes to substantially increase the precision and accuracy of hydrocarbon source recognition methods. The approach presented here evaluates a goodness-of-fit metric between the measured hydrocarbon composition of an environmental sample and a suspected source, after correcting for PAH weathering losses based on FOLR kinetics. Variability from analytical and sampling error may thus be accounted for, and source identifications can be expressed as objective probability statements. This approach is illustrated by application to four independent case studies. [Copyright &y& Elsevier]

The successful application of forensic geology to contamination studies involving natural systems requires identification of appropriate endmembers and an understanding of the geologic setting and processes affecting the systems. Studies attempting to delineate the background, or natural, source for hydrocarbon contamination in Gulf of Alaska (GOA) benthic sediments have invoked a number of potential sources, including seep oils, source rocks, and coal. Oil seeps have subsequently been questioned as significant sources of hydrocarbons present in benthic sediments of the GOA in part because the pattern of relative polycyclic aromatic hydrocarbon (PAH) abundance characteristic of benthic GOA sediments is inconsistent with patterns typical of weathered seep oils. Likewise, native coal has been dismissed in part because ratios of labile hydrocarbons to total organic carbon (e.g. PAH:TOC) for Bering River coal field (BRCF) sources are too low—i.e. the coals are over mature—to be consistent with GOA sediments. We present evidence here that native coal may have been prematurely dismissed, because BRCF coals do not adequately represent the geochemical signatures of coals elsewhere in the Kulthieth Formation. Contrary to previous thought, Kulthieth Formation coals east of the BRCF have much higher PAH:TOC ratios, and the patterns of labile hydrocarbons in these low thermal maturity coals suggest a possible genetic relationship between Kulthieth Formation coals and nearby oil seeps on the Sullivan anticline. Analyses of low-maturity Kulthieth Formation coal indicate the low maturity coal is a significant source of PAH. Source apportionment models that neglect this source will underestimate the contribution of native coals to the regional background hydrocarbon signature. [Copyright &y& Elsevier]

Two samples of college students (n = 40 each) drawn from a larger sample (N = 188) were identified as high creative or low creative based on their performance on 5 measures of creativity that included both tests of creativity and actual creative production such as haiku poetry. The students were then interviewed with a semistructured procedure, and the video recordings of the interviews assessed as to the utilization of each of 15 ego defense styles. Thirteen of the 15 ego defense styles showed statistically significant mean differences, with high creatives scoring higher on schizoid fantasy, acting out, dissociation, displacement, reaction formation, intellectualization, humor, suppression, and sublimation; they scored lower on projection, passive aggressiveness, repression, and altruism. [ABSTRACT FROM AUTHOR]

Modifications in the electrified basket for anesthetizing fish make it more portable and easier to use. Modifications include the use of six electrodes instead of two and the addition of a circuit switch, removable handles, and webbing that makes fish easier to reach for tagging. The basket can anesthetize juvenile chinook salmon (Oncorhynchus tshawytscha) and coho salmon (O. kisutch) as small as 20 cm. [ABSTRACT FROM PUBLISHER]

Injury to a species resulting from long-term exposure to low concentrations of pollutants is seldom noted or even tested. One of the products of the Exxon Valdez oil spill was the first report of damage to eggs and larvae of pink salmon (Oncorhynchus gorbuscha) following long-term exposure to low concentrations of weathered crude oil. These life stages were previously thought to be highly resistant to injury from oil. Growth rate among migrating fry was depressed, and the population was reduced via size-dependent mortality. Elevated egg mortality in oiled streams continued for at least 4 years after the spill. Laboratory tests verified that embryos are sensitive to long-term exposure to weathered oil in the low parts per billion range. These results are compared with those of studies conducted by investigators funded by Exxon Corporation and, where controversy exists, we attempt to reconcile the studies. These findings are important to the pink salmonfisheries of Prince William Sound (PWS) and are also broadly applicable to toxicity and impact from nonpoint source pollution of urban estuaries. [ABSTRACT FROM AUTHOR]