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Total mercury and selenium concentrations were determined in 47 swordfish caught in the north-west Atlantic ocean. Only 10 swordfish had total mercury levels equal to or below the World Health Organization (W.H.O.) limit of 0.5 μg of mercury/g of fish. All fish had significant quantities of selenium. All fish that contained mercury up to 2 mg/g had a molar excess of selenium compared to mercury.Two hundred and fifty-one swordfish were analyzed for total mercury and only 12 fish or 4.8% contained more than 2 ng/g total mercury; therefore, it was concluded that in most swordfish there was a molar excess of selenium in relation to mercury.Since selenium has been shown to lower the toxicity of methyl mercury in animal studies by other investigators, it was suggested that the use of swordfish for food should be reviewed.

The reduction of arsenate ion to arsenite ion by a variety of tissues was widely distributed, and not a property of any particular tissue. The nature of the reduction was investigated by using various chemical inducers and inhibitors and is believed to be chemical in nature.

Arsenite ion, as arsenic trichloride was extracted into benzene from strongly acidified tissue homogenates. Following this, arsenite was extracted from the benzene into water, made up in 1N HCl and analyzed polarographically. Arsenate ion, left in the homogenate after arsenite extraction is isolated in exactly the same way following treatment of the homogenate with cuprous ion to reduce arsenate to arsenite ion. Treatment of the acidified homogenate with cuprous ion prior to extraction gives a homogenate which is readily analyzed for total “inorganic” arsenic. The method was efficient to a maximum level of about 20 μg inorganic arsenic since at higher levels lower recoveries were found. Analysis of a variety of marine biological specimens, with levels of total arsenic up to 40.5 ppm, indicated little of this arsenic was present in an inorganic form. Post mortem reduction of arsenate to arsenite was found to occur rapidly in fish tissue.

Field studies on the use of coated polyurethane foam plugs as indwelling water monitors and studies of the ability of such foams to quantitatively extract polychlorinated biphenyls, dieldrin and members of the DDT complex were carried out using waters of an industrial nature and agricultural nature. Recoveries of all spiked materials were generally in excess of 90%. Indwelling foams took from 24-48 hours to reach plateau values and from the levels of plateaus reached it is suggested that only the external surface of the porous plug is active. Use and reuse of plugs as well as extraction in the field is easily accomplished.

Castrated male pigs were injected with approximately .2 mg of CdCl2 five times a week for 12 weeks. Twenty-one organs or sites were sampled to determine the distribution of cadmium in tissues. Concentrations in endocrine glands (wet weight) of 77-90 μg/g in pancreas, 14-21 μg/ in adrenal, 7,7 - 11 μg/g in pituitary, and 1.1 - 6.3 μg/g in thyroid indicate the need for more through examination of the functioning of these organs in the presence of cadmium.

Differences observed in autoradiogram profiles and isotope ratios or corticosteroid metabolites (such as cortisol), in vitro, in interrenal activity between and within hatchery reared salmon (Salmo salar) parr stocks were not observed in corresponding wild stocks. Wild fish from nine Nova Scotian rivers (Annapolis, Black, East, Gold, LaHave, Medway, Musha-mush, Salmon, and Stewiacke Rivers), sampled during May to December all showed similar corticosteroid profiles. Differences were observed in corticosteroid profiles in December between: (1) hatchery stock held in acidic and circumneutral rivers; and (2) hatchery stock held in cages in a limed river, wild stock from this river, and hatchery stock maintained at the hatchery. Copyright 1994, 1999 Academic Press

The aluminum chloride catalyzed reaction between β-14C-ethyl iodide and benzene in 1,2,4-trichlorobenzene as solvent was studied under different conditions of temperature and reaction time. Yields of ethylbenzene were estimated by isotopic dilution. Up to 20% rearranged product, α-14C-ethylbenzene, was found. The trend indicated that yield of ethylbenzene was lower and side chain rearrangement greater when the reaction mixture was heated at higher temperature for longer time. The rearrangement apparently occurred after the initial formation of β-14C-ethylbenzene. After a reaction time of 5 min at 154 °C, only 0.1–0.3% unreacted and unrearranged β-14C-ethyl iodide was recovered while the ethylbenzene obtained from the reaction showed about 2% rearrangement. When β-14C-ethylbenzene was heated with aluminum chloride in 1,2,4-trichlorobenzene for 2 or 24 h, rearrangement to α-14C-ethylbenzene was observed. In some experiments, a fragmentation product, toluene, was isolated. Its specific activity suggested that 1 mole of active ethylbenzene gave 2 moles of toluene only one of which was active. The mechanistic implications of these findings are discussed.