Surveillance of drinking-water quality

286 Some of these are: From each of the urban areas, one site was selected downtown, another in an "industrial area" and a third in a "residential area". As pollutant concentrations mostly decrease from the city centre towards the suburbs, the first of the sites, viz., "downtown" is relatively easy to locate as coincident with the highest values recorded. These concentrations and only these are fairly well comparable for the 14 selected cities. But where exactly the other two sites are situated on the descending branches of the bell-shaped pollution curve, is anybody's guess. Thus the comparability of sites other than downtown must be considered with great circumspection. It does not matter enormously that for sulphur dioxide at least three different methods were used. On the contrary, the non-uniformity of methods may be decisive for suspended particulates, e.g. monthly geometric means during the monsoon months (by the gravimetric HiVol method) appear among the highest in Calcutta. Smoke shade, by far not an absolute method and nevertheless reported from four out of the 14 survey areas, would have ranked Calcutta among the lowest. Finally, the frequency distributions of the pollutants are variously based on weekly, daily or hourly samples. In that way, systematic discrepancies must and do appear in the computed geometric standard deviations of the (approximately lognormal) concentration frequency distributions. A summary of the various measurement methods is clearly spelled out in the text, accompanied by some, but not enough warning against the snares here analyzed. This means that the authors, as air pollution specialists, were fully aware of the pitfalls and nevertheless underestimated the frequency with which other interested users might fall into the pits. Vert-le-Petit (France) Michael M. Benarie

Surveillance of Drinking-Water Quality, World Health Organisation Monograph Series No. 63, World Health Organization, Geneva, Switzerland, 1976, 135 pp. Price: Sw. Fr. 29.00.

This volume presents a practical guide for planning, organizing and operating programmes for surveillance of drinking water quality for developing and developed countries. The overall emphasis is placed upon health with particular attention being directed towards aspects of bacteriological quality and operational activities for community water services. The latter half of this monograph consists of a series of annexes presenting practical examples of all aspects of surveillance including details of water supply construction, ranging from specifications of vents and manhole covers, well and storage structure, domestic fittings, and an example of a sample reporting form for municipal water supply sanitary surveys. Methods for chemical analysis are considered in some detail but only two items are discussed, namely, residual chlorine concentration and membrane-filter test for

287 coliform bacteria. Somewhat surprising the ortho-tolidine test is still advocated although it is noted that this reagent is highly dangerous to health. There is no discussion concerning hazards likely to arise because of the presence of elements in water or even a listing of those considered to be of concern, for example, lead. In developing countries, there is no question that vast improvements in health of communities result from improved sanitation associated with water supplies. If good health can be achieved by adequate chlorination and bacteriological control for developing countries, then perhaps some readers might ask the question why the same cannot be applied to developed countries? A feature of technologically advanced countries is the expenditure of quite considerable sums of money on inorganic and organic analysis of water. Providing that common sense prevails in selecting water supplies, perhaps all that is needed for many areas is a little more chlorine and improved filtration of water. There is of course the question of recycling water in advanced countries which has its own problems, but the title of the monograph provides no indication that emphasis is placed on developing countries. Plymouth (England) E.I. Hamilton

N.P.S. Global Cycles, Ecological Bulletins, NFR 22 Score Report 7, Editor-in-Chief T. Rosswall, by B. H. Svensson and R. S6derland (Editors), Royal Swedish Academy of Sciences, 1976, 192 pp, A report of a Workshop held at Orsundsbro, Sweden in December 1975 which brought together 29 international experts in the cycling of nitrogen, phosphorus and sulphur, elements whose biochemical cycles constitute the life-supporting system of our planet. The Bulletin consists of 9 papers and each contribution provides an excellent evaluation of budgets, flow of components through and mechanisms mediating their conversions and transport especially those of global dimensions. It is rare to find so much information obtained from many disciplines welded together in such an expert and readable manner; major problems are identified and suggestions made for future research. Data are presented in a simple manner, complex mathematics are not used neither are detailed scientific arguments pursued for any length; the text deals with basic facts, provides essential equations to derive numbers relevant to practical problems of human interactions with the natural environment. Plymouth (England) E.I. Hamilton

Marine Pollution, edited by R. Johnston, Academic Press, London, 1976, xiv + 730 pp. Price: £ 23.40. An objective of this volume is to provide a much wider understanding of the nature, effects, mechanisms and control of marine pollution. The volume is divided into four parts, Mechanisms in Marine Pollution, Topics in Marine Pollution,