Exposure of marine birds to environmental pollutants / by Harry M. Ohlendorf, Robert W. Risebrough, Kees Vermeer.

Abstract

It is unlikely that any marine birds remain uncontaminated by the synthetic organochlorine compounds that have become ubiquitous pollutants. Marine birds also are increasingly exposed to petroleum compounds as a result of the exploitation of undersea petroleum deposits, increased tanker traffic, and expansion of coastal petrochemical industries.Lethal and reproductive effects of organochlorines on marine birds have been most pronounced in coastal areas receiving effluents discharged by manufacturing plants. For example, particularly severe DDT contamination in southern California and elevated levels of dieldrin and related chemicals in the Netherlands have killed local marine birds or inhibited their reproduction.Eggshell thinning, apparently resulting from exposure to DDE, is widespread among estuarine species, and eggshells of peregrine falcons {Falco peregrinus) have become thinner in all areas of the species' range thus far studied. In more contaminated coastal areas, reproductive success of the peregrine falcon is low. Adverse effects of organochlorines on the reproduction of other species also have been found.The oihng of feathers and the associated mortality of marine birds are not the only adverse effects of oil pollution; ingestion of oil may cause death by dehydration by interfering with ion transport and water balance in the gut. Surfactants used to disperse oil spills also have serious consequences for marine birds. Dissolved oil fractions may kill or poison the biota the birds feed on. The physiological effects of the incorporation of more persistent compounds into marine food webs are unknown.Contamination of marine birds by most metals and certain trace elements has not been documented, although elevated mercury levels have been observed in birds of certain estuarine and local marine environments. The significance of elevated mercury levels and small plastic particles found in the stomachs and pellets of marine birds is not yet known.' A summary of this paper was presented at the 13-15 May 1975 international symposium on "Conservation of Marine Birds of Northern North America," in Seattle, Washington. The paper was written in 1975-76, and certain portions have been amended or updated as references were pubHshed. Proceedings of the symposium are being prepared for publication, but this paper on environmental pollutants is being published separately because of its great length and the delay in pubhcation of the entire Proceedings.(1) The largest source is the chronic dribbling of oil into the coastal zone by industrial and municipal effluents, urban runoff, and river runoff carrying oil from inland areas. A substantial amount of oil, therefore, will be discharged to the coastal zone regardless of source. This amount will increase as oil consumption increases unless control steps are taken. Evidence suggests that chronic lowlevel pollution could be potentially more damaging to ecosystems than isolated catastrophic spills (Evans and Rice 1974).(2) It may be safer for the total marine environment to dri...

Secondary structure determination for the Antennapedia homeodomain by nuclear magnetic resonance and evidence for a helix-turn-helix motif.

“…wt and high solubility in water make this protein amenable for a determination of its 3-dimensional structure by NMR Wiithrich, 1986). Here we describe the secondary structure determination by NMR for the homeodomain of the antennapedia protein from Drosophila, and present preliminary evidence for the presence of a helix-turn-helix motif similar to that found in several prokaryotic gene regulatory proteins (Ohlendorf et al, , 1983Steitz et al, 1982;Zuiderweg et al, 1984;Ptashne, 1986;Mondragon et al, 1988).…”

“…Computer modelling using the present, preliminary NMR data indicates that the homeodomain contains a helix-turn-helix motif The DNA-binding properties of the homeodomain and the presence of the short segment of irregular structure between helices 2 and 3 (Figure 1) are suggestive of a structural relationship with a group of prokaryotic repressor proteins, which contain a conserved helix-turn-helix motif as the DNA recognition site (Ohlendorf et al, , 1983Steitz et al, 1982;Zuiderweg et al, 1984;Ptashne, 1986;Mondragon et al, 1988). Since the presently available NMR data are not sufficient as an input for a computation of the complete 3-dimensional structure of the homeodomain, we used a modeling approach to investigate the compatibility of the preliminary experimental observations with a helix-turn-helix motif of the type seen in the prokaryotic proteins.…”

The behaviour of drag-reducing cationic surfactant solutions

“…It has been shown that these and other cationic surfactants in combination with a variety of different organic ions, e.g., sodium salicylate, can be used as drag reducing agents [7,9,13,[19][20][21][22][23] in water. These surfactant systems give rise to rod-like micelles.…”

Drag‐reducing surfactants

“…To circumvent the problems of making a pure N,N-dihydroxyethylalkylamine, an alkyldimethylamine can be quaternized with ethylene oxide with an acid catalyst (23). This method has formed the basis for a line of commercial DR products in which the additive consists of either salicylate or 2-hydroxy-3-naphthoate.…”