ISO INTERNATIONAL STANDARD 11266 First edition 1994-09-15 Soil quality --- Guidance on laboratory testing for biodegradation of organic chemicals in soil under aerobic conditions Qualite du sol - Guide relatif aux essais en laboratoire pour la biodegradation de produits chimiques organiques dans le sol sous conditionsaérobies ISO Reference number ISO 11266:1994(E) No reproduction c Not for Resale ISO 11266:1994(E) Foreword ISO (the international Organization for Standardization) is a worldwide preparing International Standards is normally carried out through IsO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with IsO, also take part in the work. IsO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard ISO 11266 was prepared by Technical Committee ISO/TC 190, Soil quality, Subcommittee SC 4, Biological methods. Annexe A of this International Standard is for information only. @ISO1994 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm,withoutpermission inwritingfromthepublisher. InternationalOrganizationforStandardization Case postale 56 : CH-1211 Geneve 20 Switzerland PrintedinSwitzerland ii Copyright Intermational Organization for Standardization No reproduction or networking permitted without license from IHS Not for Resale ISO 11266:1994(E) @ISO Introduction Organic chemicals may be introduced into the soil both intentionally and accidentally, after which they may, or may not, degrade biologically. For chemicals which do degrade, the rate of degradation can vary con- siderably, depending not only on the molecular structure of the chemical, but. also on soil conditions such as temperature, water and oxygen availability which influence microbial activity. The activity ofmicro organisms often plays a major role in degradative processes. It is necessary to have laboratory tests available to estimate the rate and in soil. Numerous laboratory methods are available for the estimation of aerobic biodegradation, but these differ considerably according to the specific circumstances, for example, soil type, temperature and incubation times. This International Standard provides general guidelines for the selection and conduct of tests for determining the biodegradation of organic chemicals in aerobic soils. At the time of writing, there is insufficient agreement on methodology for testing biodegradability in anaerobic soils for guidelines to be prepared. imi ited without license from IHs Not for Resale