BackgroundIn this commentary we present the findings from an international consortium on fish toxicogenomics sponsored by the U.K. Natural Environment Research Council (Fish Toxicogenomics—Moving into Regulation and Monitoring, held 21–23 April 2008 at the Pacific Environmental Science Centre, Vancouver, BC, Canada).ObjectivesThe consortium from government agencies, academia, and industry addressed three topics: progress in ecotoxicogenomics, regulatory perspectives on roadblocks for practical implementation of toxicogenomics into risk assessment, and dealing with variability in data sets.DiscussionParticipants noted that examples of successful application of omic technologies have been identified, but critical studies are needed to relate molecular changes to ecological adverse outcome. Participants made recommendations for the management of technical and biological variation. They also stressed the need for enhanced interdisciplinary training and communication as well as considerable investment into the generation and curation of appropriate reference omic data.ConclusionsThe participants concluded that, although there are hurdles to pass on the road to regulatory acceptance, omics technologies are already useful for elucidating modes of action of toxicants and can contribute to the risk assessment process as part of a weight-of-evidence approach.

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Peat moss (Sphagnunt) from the surface of a n Atlantic peat bog has been extracted with a mixture of benzene and ethanol. The extract has been fractionated chromatographically 011 alumina. A mixture of sterols has been isolated from one fraction. 'This mixture has been proved by oxidation experiments to consist of 8-sitosta~lol (stigmastanol) and 8-sitosterol. I t constit~~ted approximately 0.2y0 by weight of the dried peat ~noss. INTRODUCTIONA considerable amount of work has been done on the chemical composition of peat (8), lignite (brown coal) (8)) and coal (8), but relatively little on the conlposition of peal: moss (Sphagnum). The latter is considered to be the main precursor of peat in the Atlantic area of Canada. This work was undertalien ill a n effort to remedy this defect, and also to ascertain what chemical changes occur in huinification. Black and his coworkers (4) carried out an extensive analysis on a sample of peat moss from Scotland and reported the presence of p-sitosterol.The peat moss used in our experiments was a living surface moss, from Shipigan, New Brunswick, ancl was essentially a mixture of Splzngnunz fuscum, S . capillacer~m, and S . magellanicum with the first two predominating. It was comparatively free of other common bog plants. T h e moss was clried to a moisture content of approximately 5% and ground to pass through a 20-mesh screen. Only relatively small quantities of the powder could be extracted a t a time, ouring to its bull;. The process used was a continuous extractioi~ method, with a constant stream of pure solvent passing through the moss.After evaporation of the solvent, the clarl; brourn guin (approximatell. 6% of the total solids) was saponified with methanolic potassiun~ hydroxide solution ancl the unsaponiliable material extractecl with ether. This extract (approximately 1.5% of the total solids), after evaporation, was dissolved in light petroleum and chromatographed roughly on alumina. A small portion of the gun1 (approximately 3%) did not dissolve in the petrol and was kept for further investigation. The eluate from the chromatogram was divided into five fractions: materials eluted progressively by ( a ) light petroleum, (b) benzene, (c) ether, (d) ether containing 10% ~nethanol, and (e) ~nethanol. These iractioils will be described separately. T h e coinposition of fractions (c) and (d) varied from extraction to extraction and with the grade of alumina used. The ether fraction so~netimes consisted of a white, low-melting solid, and the ether-methanol fraction of a colorless crystalline solicl, subsequently proved t o be the sterols. In the majority of extractions, however, the con~ponents were c nixed and tended to be removed fro~n the column together in fraction (d) as a light yellow glass. T h e ~nixture was separated into cyclic and linear aliphatic compounds by treatment with urea with which the latter formed an insoluble complex. Decompositio~l of the complex yielded an alcohol which has been tentativel!. identified as lignoceryl alcohol by meltin...

By further chromatographic fractionation of the unsaponifiable matter from an extract of peat moss (Sphagnunz) three crystalline triterpenes have been isolated. They have been identified as a-amyrin, taraxerone, and taraxerol by their physical and chemical properties.In the preceding paper (5) the method of separating the crude unsaponifiable material present in peat moss was described. Two sterols were isolated and identified. This paper deals with some of the other compounds isolated during the chromatography of the crude extract. The fraction of unsaponifiable material eluted from the alumina column with benzene represented approximately five per cent of the total. This material consisted of a light yellow oil which crystallized on standing. Attempts to purify it by crystallization from methanol or ethanol failed. However, if the material was taken up in light petroleum, a yellow sirup was dissolved leaving a white crystalline mass, which after filtration could be readily recrystallized from chloroform-methanol solution. T h e crystals melted a t 238'-239' and had a specific rotation of f12". The material gave a crystalline derivative with 2,4-dinitropheny1h)rdrazine and showed a marked peak in the infrared a t 1705 cm.-I, indicative of a carbonyl group. The infrared spectrum of this ketone from peat moss also showed the presence of a double bond by a band a t 816 cm.-l and the position of the band indicated a trisubstituted double bond in a six-membered ring. The high melting point and comparatively few functional groups, in addition to a positive Liebermann-Burchard reaction, indicated that the compound could be a triterpene, possibly of the allobetulin series. This hypothesis was reached since derivatives of allobetulin have been found in lignite (8), a decomposition product of peat. However, analysis showed the presence of only one oxygen function, the carbonyl group, whereas allobetulin itself has two, one being an ether function. A search of the literature showed that the lietone was possibly taraxerone (I), previously isolated from Tara.xacum oficinale (3) and Aln7rs glz~ti~zosa L. ( I ) , and further chemical evidence confirmed this. The Icetone was reduced with lithium aluminum hydride to give the alcohol (11, R = H ) , which had the physical constants of taraxerol. This was confirmed by the preparation of the acetate in the usual way (11, I< = Ac). This acetate was treated with hydrochloric acid in acetic acid ( I ) and the resulting product crystallized from chlorofornl-methanol to give 0-amyrin acetate (111, R = Ac), identified by melting and rotation and the melting point and rotation of the derived alcohol (111, I< = H) 0-amyrin. This rearrangement has been shown to involve the migratio~l of a methyl group from C13 to C1.l with the concomitant movement of the double bond from the 14,15-position to the 12,13-position. The process is concerted and there are no intermediates. I t is also irreversible and the yield of P-amprin is virtually 100%. The rearrangement is typical of taraxerol and ...