Effects of Endosulfan (Thiodan 35 EC®) on Meiofauna Community Through a Microcosm Approach
Abstract
A microcosm experiment with natural community of meiofauna was performed to test the effects of the organochlorine pesticide Thiodan 35 EC (35% endosulfan) at concentrations more likely to reach the estuaries by the sugar cane crops runoff. A methodological proposal for microcosms was tested for tropical estuaries. The nominal concentrations (0.001, 0.005, 0.01, 0.05, 0.10, 0.20, 0.35 and 0.55 μg.g-1 + control) and experimental times (0, 1, 4, 8 and 16 days) were adopted. Nominal and measured endosulfan concentrations in Thiodan showed highly significant correlation with losses below 60%. Significant differences were detected for meiofauna structure between experimental days and concentrations tested. The organochlorine Thiodan measured as endosulfan concentrations had affected the Kinorhyncha group on Day 8 and the Simple Linear Regression explained part of densities variation. There were no significant concentration effects on microphytobenthos and its concentration was not related to groups’ feeding. Despite the moderate to high volatilization rate of the endosufan observed in the end of the experiment, it is suggested the absence of mortality patterns due to pesticide bioavailability related to both sedimentary factors and the presence of microalgae. Possible replacement of sensitive by tolerant species or predominance of resistant species in each meiofauna group throughout the experiment is another hypothesis to be discussed.
Keywords: meiofauna, microcosm, pesticide, endosulfan, Thiodan, sugar cane, microphytobenthos.
Downloads
Downloads
How to Cite
Issue
Section
License
Copyright © 2006 ECOTOX-Brasil
Copyright notice: It is a condition for publication that manuscripts submitted to this journal have not yet been published and will not be simultaneously submitted or published elsewhere. By submitting a manuscript, the authors agree that copyright for their article is transferred to the Sociedade Brasileira de Ecotoxicologia (ECOTOX-Brasil) if and when the article is accepted for publication. The copyright covers the exclusive rights to reproduce and distribute articles, including reprints, photographic reproductions or any other reproduction of a similar nature, including translations. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without permission of the publisher.
Notice: While every effort is made by the EEC, editors and editorial board to see that no inaccurate or misleading data, opinions or statements appear in this journal, they wish to make it clear that the contents of the articles and advertisements published herein are the sole responsibility of the contributors or advertisers concerned. Accordingly, the EEC, the editorial board and editors and their respective employees, officers and agents accept no responsibility or liability whatsoever for the consequences of any inaccurate or misleading data, opinion or statement.
