Biomedical subjects
Publications and source records attributed to D J Lisk.
Pollen collected from the rear legs of honey bees found foraging on asters voluntarily growing on a fly ash dump in Endwell, New York, was found to contain a high concentration of selenium. Pollen from bees foraging on asters growing on field soil contained no detectable selenium.
A number of commercial and candidate flame retardants were studied with regard to their toxicity to fish when released from fabrics immersed in their water. Immersion of laundered or unlaundered flame retardant 100% polyester or polyester blend fabrics used in children's sleepwear in water containing goldfish resulted in release of the anticholin-esterase flame retardant TDBPP (tris (2, 3-dibromopropyl) phosphate) and death of all fish within 24 hours. TDBPP undergoes loss of HBr in water and production of a metabolite.
A number of commercial and candidate flame retardants were studied with regard to their toxicity to goldfish, inhibition of cholinesterase, inhibition of acetyl choline binding to its receptor and insecticidal properties. Several of the flame retardants were notably toxic to fish. Some of the compounds showed modest inhibition of cholinesterase and/or microsomal oxidases, but none inhibited acetyl choline receptor binding. Whereas several of the flame retardants showed little or no insecticidal properties when added alone to a housefly diet, piperonyl butoxide greatly synergised their toxicity to houseflies.
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Gross and histologic examination of wood chcks (Marmota monax) trapped on farms in Central New York revealed white muscle disease(WMD). The concentration of selenium in the animal tissues, vegetation and soils in the vicinity of trapping did not consistently correlate with the presence of WMD.
Selenium, at concentrations exceeding 200 parts per million (ppm) (dry weight), has been found in white sweet clover voluntarily growing on beds of fly ash in central New York State. Guinea pigs fed such clover concentrated selenium in their tissues. The contents of the honey stomachs of bees foraging on this seleniferous clover contained negligible selenium. Mature vegetables cultured on 10 percent (by weight) fly ash-amended soil absorbed up to 1 ppm of selenium. Fly ashes from 21 states contained total selenium contents ranging from 1.2 to 16.5 ppm. Cabbage grown on soil containing 10 percent (by weight) of these fly ashes absorbed selenium (up to 3.7 ppm) in direct proportion (correlation coefficient r = .89) to the selenium concentration in the respective fly ash. Water, aquatic weeds, algae, dragonfly nymphs, polliwogs, and tissues of bullheads and muskrats from a fly ash-contaminated pond contained concentrations of selenium markedly elevated over those of controls.
An investigation was made of the possible migration of a flame retardant, tris (2,3-dibromopropyl) phosphate (TBPP), commercially used in childrens sleepwear, to the skin of rats and humans and subsequent absorption. When the pure chemical was applied directly to the shaved skin of a rat, the hydrolysis product, 2,3-dibromopropanol (DBP), appeared in the urine. The 10,000 X g supernatant fraction of rat liver hydrolyzed TBPP to DBP. When TBPP-finished fabrics were worn by a rat, an adult male and a 5-year-old boy for up to 9 days, DBP was not detected in the urine.
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Visible injury to apple foliage from exposure to ozone includes brown stippling on lower leaf surfaces and a light yellow mosaic on upper surfaces. Histologically, chlorophyll is destroyed and palisade and spongy mesophyll cells collapse following disintegration of their protoplasm. Foliar spray applications of the antioxidant, diphenylamine (DPA) or the antitranspirant, Wilt Pruf offer protection against this visible and histological injury. Superior protection results from application of both agents in combination.
An analytical survey has been conducted of 42 elements, p,p'-DDE, dieldrin andpolychlorinated biphenyls in 31 commercial canned pet foods. Neutron activation analysis, graphite furnace atomic absorption, anodic stripping voltammetry, electron affinity gas chromatography and other methods were used. Arsenic, bromine, cadmium, chromium, mercury, selenium and DDE were highest in fish-containing cat foods. Lead was most consistently high in those products containing chicken. Barium, nickel and tin also appeared high in certain of the samples.
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The herbicide, Kerb ((N-(1,1 dimethylpropynyl)-3,5-dichlorobezamide) was fed to a lactating cow at a concentration of 5 ppm in the ration for four days. Excretion of residues of equivalent herbicide in milk, urine and feces were found to be, respectively, 0.19, 44.38 and 4.46% of the total dose.
Nineteen samples of honey taken from grocery shelves, near zinc mines, adjacent to an industrial area, and near a major highway, and one sample collected in 1899 were subjected to spark source mass spectrometry to determine the concentration of most of 47 elements in the honey. Certain samples of honey produced by bees in the vicinity of the New York State Thruway appeared to contain elevated levels of certain elements known to be emitted by traffic, such as aluminum, barium, calcuim, copper, magnesium, nickel, palladium, and silicon, but the true source of these elements was uncertain. Honey that had come into contact with metal containers in processing contained the greatest amounts of zinc and tin.
One may conclude that it is impractical to confine oneself to any one analytical method since ever more sensitive instrumentation continues to be produced. However, in certain methods such as anodic stripping voltammetry and flameless atomic absorption it may be background contamination from reagent impurities and surroundings rather than instrument sensitivity which controls the limits of element detection. The problem of contamination from dust or glassware is greatly magnified when the sample size becomes ever smaller. Air entering laboratories near highways may contain trace quantities of lead, cadmium, barium, antimony, and other elements from engine exhaust. Even plastic materials contacting the sample may be suspect as a source of contamination since specific metals may be used as catalysts in the synthesis of the plastic and traces may be retained in it. Certain elements may even be deliberately added to plastics during manufacture for identification purposes. Nondestructive methods such as neutron activation and x-ray techniques thus offer great advantages not only in time but in the elimination of impurities introduced during sample ashing. Future improvements in attainable limits of detection may arise largely from progress in the ultrapurification of reagents and "clean-room" techniques. Finally, the competence of the analyst is also vitally important in the skillful operation of modern complex analytical instrumentation and in the experienced evaluation of data.
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