Effects of DDT and piperonyl butoxide on the metabolic alterations in pigeon (Columbia livia)

Effect of acute doses of technical grade of dichloro diphenyl trichloro ethane (DDT) and piperonyl butoxide (PB) on hepatic microsomal cytochrome P450 (Cyt. P450) and cytosolic glutathione-S-transferase (GST) activity in pigeon were studied after 24 hours of treatment. A completely reverse trend of changes in Cyt. P450 and GST activity were found as increase in Cyt. P450 paralleled with decrease in GST activity following exposure to DDT. However, intensity of changes in Cyt. P450 was greater than that of GST. A dose dependent decrease in Cyt. P450 and GST activity was observed after PB treatment. The study may, therefore, throw some light on metabolic alterations in wild birds resulting from environmental pollution by DDT and allied chemicals.     

Trace Metals in New England Marine Sediments: Casco Bay, Maine, in relation to Other Sites

The concentrations in surface sediments of the trace metals Cd, Cr, Cu, Ni, Pb and Zn have been determined at 32 stations in the Casco Bay region of the Gulf of Maine. The metals are not distributed homogeneously but exhibit elevated levels around the Portland waterfront and generally low levels at offshore and tidally scoured stations. Comparison of these results to those from both industrialized and non-industrialized sites throughout New England indicates that the sediments in parts of the Casco Bay region are affected by trace metals.     

Investment and future mineral production

The author reviews recent estimates of world resources and reserves and notes that reserves tend to grow with mineral consumption. Legal and economic constraints to the extraction of minerals are at least as important as physical availability. The author also points out that there is far more investment in minerals (government induced investment, companies diversifying into mining, etc) than some commentators suggest. However, the large mining projects of the 1960s belong to the past, and supplies of minerals may well become tight if there is a concerted economic boom.     

Reviews

DESIGN ON THE LAND: the development of Landscape Architecture Norman T. Newton Belknap Harvard

COMMUNITY CENTERS AND STUDENT UNIONS Eugene D. Sternberg and Barbara E. Sternberg Van Hostrand Reinhold Company, New York.

DECISION AND CONTROL by Stafford Beer, John Wiley and Sons, Inc., New York, 1966 (3rd printing, 1970)

INDUSTRIAL DYNAMICS by Jay W. Forrester, M.I.T. Press, Cambridge, Mass., 1961. S.1O.5O.

PRINCIPLES OF SYSTEMS by Jay W. Forrester. Wright‐Allen Press, Inc., Cambridge, Mass., 1968.

PUBLIC INQUIRIES AS AN INSTRUMENT OF GOVERNMENT R.E. Wraith and G.B. Lamb George Allen & Unwin Ltd. for the Royal Institute of Public Administration, London 1971, £4.50.

SYSTEMS APPROACH AND THE CITY M.D. Mesarovic and A. Reisman (eds.) North‐Holland Publishing Co., Amsterdam and London, 1972.

SIMULATION IN THE CLASSROOM John L. Taylor and Rex Walford Penguin Books, London, 1972. 45p.

DEVELOPMENT BUILDING: THE TEAM APPROACH C.W. Griffin John Wiley & Sons, Inc. for the American Institute of Architects, New York, 1972.