Treatability of nonylphenol ethoxylate surfactants in on-site wastewater disposal systems.

The fate of nine-mole nonylphenol ethoxylate (NPE9) discharged to an on-site wastewater disposal (septic) system was the focus of a 2-year investigation. Known amounts of NPE9-based detergent were metered daily into the plumbing at a single-family household. The ethoxylate-containing wastewater was discharged to the highly anoxic environment of a 4500-L septic tank before distribution to the oxic subsurface via 100 m of leach line. After 180 days of injecting detergent to the septic system, periodic soil pore water and/or groundwater samples were collected and analyzed for nonylphenol ethoxylates (NPEs), nonylphenol ether carboxylates, and nonylphenol. The NPE9 and degradation intermediates that were measured were reduced by 99.99% on a molar basis. An 18% reduction in molar concentration within the septic tank was observed. This was followed by a further 96.7% reduction of molar concentration within the leach lines. As the pore water migrated through the vadose zone, an additional 99.69% reduction in molar concentration was measured between the bottom of the leach lines (leach line effluent) and the lowest vadose zone monitoring location. The results obtained from these analyses indicate that degradation of the surfactant occurs within the anoxic portion of the disposal system with continued rapid biodegradation in the oxic unsaturated zone. Only trace amounts of degradation residuals were detected in soil pore water. The concentration and distribution of various degradation intermediates with respect to location, time, and ambient physical conditions were evaluated. Rapid and systematic degradation of NPE in on-site wastewater disposal systems was documented.     

Book reviews

PIONEERS IN BRITISH PLANNING

Gordon Cherry (Ed.)

The Architectural Press, London, 1981. 232 pp with index and illustrations.

Price £8.95 paperback.

PLANNING PROCEDURES

John Stephenson

Northwood Books, 1982

Price £9.95 hardback, 192 pages

INDUSTRIAL LOCATION POLICY FOR ECONOMIC REVITALISATION

Morris L. Sweet

Praeger, 1981

THE POLITICS OF TOWN PLANNING

Gordon Cherry

Longmans, 1982. 165 pp.

THE POLITICS OF LOCAL GOVERNMENT IN THE UNITED KINGDOM

Alan Alexander

Longman, 1982, 143 pp. Price £3.95 paperback

LAND USE AND LIVING SPACE

Robin Best

Methuen U.P., 1981

URBAN PROJECTS MANUAL

A guide to preparing upgrading and new development projects accessable to low income groups.

Forbes Davidson and Geoff Payne (Eds)

University Press 1983 Price £7.50

LONDON'S GREEN BELT: CONTAINMENT IN PRACTICE

Richard Munton

George Allen & Unwin, 1983

OUTDOOR RECREATION AND RESOURCE MANAGEMENT

John Pigram

Croom Helm, 1983

THE IDEAL CITY — ITS ARCHITECTURAL EVOLUTION IN EUROPE

Rosenau, H.

Methuen & Co. Ltd., London & New York. Third Edition 1983. 195 pages illustrated. Hardback.

ENVIRONMENTAL HAZARDS IN THE BRITISH ISLES

A. H. Perry

George Allen and Unwin, 1981

RECREATION AND RESOURCES: LEISURE PATTERNS AND LEISURE PLACES

J. Allan Patmore

Blackwell, 1983     

Evaluation of techniques used in the preparation of diesel extract samples for mutagenicity studies

Diesel exhaust particles were used to compare methods and techniques used in the preparation of particulate matter for microbial mutagenesis testing. Investigated in this study were extraction, concentration, and solvent exchange methodologies as they affected recovery of mutagenic material from diesel samples using a Salmonella typhimurium plate incorporation assay. Solvent removal methods applicable for use in determining the mass concentration of extracts were also evaluated. Results indicated that particle samples Soxhlet extracted with dichloromethane yielded higher levels of mutagenic activity than did comparative samples utilizing sonication. No difference was seen between rotary evaporation or Kuderna-Danish macro concentration of extracts to volumes > 50 mL. In comparison of micro concentration techniques to volumes < 10 mL, vortex evaporation was found to be more efficient than a modified micro Kuderna-Danish method in recovery of mass and mutagenicity. Solvent exchanged samples were found to yield higher recoveries of mutagenic activity than samples taken to dryness and then reconstituted in the bioassay solvent. A dry mass weighing procedure utilizing desiccation was found to be more acceptable than either the use of an infrared heat lamp or nitrogen blowdown for solvent removal.     

Effect on fatality risk of changing from secondary to primary seat belt enforcement

BACKGROUND: Most seat belt use laws originally passed in the United States contained language restricting enforcement to drivers already stopped for some other reason. States that have since removed this secondary enforcement restriction have reported increased seat belt use. The purpose of the present study was to estimate the effect of these law changes on driver fatality rates. METHOD: Trends in passenger vehicle driver death rates per billion miles traveled were compared for 10 states that changed from secondary to primary seat belt enforcement and 14 states that remained with secondary enforcement. RESULTS: After accounting for possible economic effects and other general time trends, the change from secondary to primary enforcement was found to reduce annual passenger vehicle driver death rates by an estimated 7% (95% confidence limits 3.0-10.9). CONCLUSION: The majority of U.S. states still have secondary enforcement laws. If these remaining secondary laws were amended, an estimated 696 deaths per year could be prevented.