Analysis of pesticides in food and environmental samples 9780849375521, 0849375525

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Analysis of Pesticides in Food and Environmental Samples

Analysis of Pesticides in Food and Environmental Samples Edited by José L. Tadeo

Boca Raton London New York

CRC Press is an imprint of the Taylor & Francis Group, an informa business

CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2008 by Taylor & Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works Printed in the United States of America on acid-free paper 10 9 8 7 6 5 4 3 2 1 International Standard Book Number-13: 978-0-8493-7552-1 (Hardcover) This book contains information obtained from authentic and highly regarded sources. Reprinted material is quoted with permission, and sources are indicated. A wide variety of references are listed. Reasonable efforts have been made to publish reliable data and information, but the author and the publisher cannot assume responsibility for the validity of all materials or for the consequences of their use. No part of this book may be reprinted, reproduced, transmitted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers. For permission to photocopy or use material electronically from this work, please access www. copyright.com (http://www.copyright.com/) or contact the Copyright Clearance Center, Inc. (CCC) 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400. CCC is a not-for-profit organization that provides licenses and registration for a variety of users. For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. Library of Congress Cataloging-in-Publication Data Analysis of pesticides in food and environmental samples / editor, Jose L. Tadeo. p. cm. Includes bibliographical references and index. ISBN 978-0-8493-7552-1 (alk. paper) 1. Pesticide residues in food. 2. Food--Analysis. 3. Pesticides I. Tadeo, Jose L. TX571.P4A52 2008 664’.07--dc22 Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com

2007030736

Contents Preface..................................................................................................................... vii Editor........................................................................................................................ ix Contributors ............................................................................................................. xi Chapter 1

Pesticides: Classification and Properties ............................................. 1 José L. Tadeo, Consuelo Sánchez-Brunete, and Lorena González

Chapter 2

Sample Handling of Pesticides in Food and Environmental Samples.............................................................................................. 35 Esther Turiel and Antonio Martín-Esteban

Chapter 3

Analysis of Pesticides by Chromatographic Techniques Coupled with Mass Spectrometry ..................................................... 59 Simon Hird

Chapter 4

Immunoassays and Biosensors .......................................................... 95 Jeanette M. Van Emon, Jane C. Chuang, Kilian Dill, and Guohua Xiong

Chapter 5

Quality Assurance............................................................................ 125 Árpád Ambrus

Chapter 6

Determination of Pesticides in Food of Vegetal Origin.................. 151 Frank J. Schenck and Jon W. Wong

Chapter 7

Determination of Pesticides in Food of Animal Origin .................. 177 Antonia Garrido Frenich, Jose Luis Martinez, and Adrian Covaci

Chapter 8

Determination of Pesticides in Soil ................................................. 207 Consuelo Sánchez-Brunete, Beatriz Albero, and José L. Tadeo

Chapter 9

Determination of Pesticides in Water.............................................. 231 Jay Gan and Svetlana Bondarenko

v

vi

Chapter 10

Sampling and Analysis of Pesticides in the Atmosphere.............. 257 Maurice Millet

Chapter 11

Levels of Pesticides in Food and Food Safety Aspects ................ 287 Kit Granby, Annette Petersen, Susan S. Herrmann, and Mette Erecius Poulsen

Chapter 12

Monitoring of Pesticides in the Environment ............................... 319 Ioannis Konstantinou, Dimitra Hela, Dimitra Lambropoulou, and Triantafyllos Albanis

Index..................................................................................................................... 359

Preface You should go on learning for as long as your ignorance lasts; and, if the proverb is to be believed, for the whole of your life. Lucius Annaeus Seneca

Consumer concerns on food safety and society awareness of chemical contaminants in the environment have increased in the past few years. As a consequence, more restrictions in the use of chemical products have been imposed at national and international levels. Pesticides are widely used for the control of weeds, diseases, and pests of cultivated plants all over the world, mainly since after Second World War, with the discovery of some organic compounds with good insecticide or herbicide activity. At present, around 2.5 million tons of pesticides are used annually and the number of registered active substances is higher than 500. However, as pesticides are toxic substances that may have undesirable effects, their use has to be regulated. Risk assessment of pesticides requires information on the toxicological and ecotoxicological properties of these compounds as well as on their levels in food and environmental compartments. Therefore, reliable analytical methods are needed to carry out the monitoring of pesticide residues in those matrices. Analysis of Pesticides in Food and Environmental Samples focuses on the analytical methodologies developed for the determination of these compounds and on their levels in food and in the environment. It includes information on the different pesticides used, sample preparation methods, quality assurance, chromatographic techniques, immunoassays, pesticide determination in food, soil, water, and air, and the results of their monitoring in food and environmental compartments. I think that this timely and up-to-date work can significantly improve the information in this research area and contribute to a better understanding of the behavior of pesticides that will lead to an improvement of their use. My sincere thanks to everyone who has contributed and particularly to all the contributors of the different chapters of Analysis of Pesticides in Food and Environmental Samples. This work is dedicated to Teresa, my wife. José L. Tadeo

vii

Editor José L. Tadeo, PhD in chemistry, is a senior researcher at the National Institute for Agricultural and Food Research and Technology, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria in Madrid, Spain. He graduated with a degree in chemistry in June 1972 from the University of Valencia and began his research career at the Institute of Agrochemistry and Food Technology, Spanish Council for Scientific Research, in Valencia, investigating natural components of plants with insecticide activity. In 1976, he was engaged in research of analytical methodologies for the determination of pesticide residues in food, water, and soil at the Jealott’s Hill Research Station in the United Kingdom. In 1977, Dr. Tadeo was a research scientist at the Institute for Agricultural Research in Valencia where his work focused on the study of the chemical composition of citrus fruits and the behavior of fungicides used during postharvest of fruits. In 1988, he became a senior researcher at the Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria. During his stay at the Plant Protection Department, the main research lines were the analysis of herbicide residues and the study of their persistence and mobility in soil. His current research at the Environment Department of the Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria is the analysis of pesticides and other contaminants in food and environmental matrices and the evaluation of exposure to biocides and existing chemicals. He has published numerous scientific papers, monographs, and book chapters on these topics. He has been a member of national and international working groups for the evaluation of chemicals, and he is currently involved in the assessment of biocides at the international level.

ix

Contributors Triantafyllos Albanis Department of Chemistry University of Ioannina Ioannina, Greece

Antonia Garrido Frenich Department of Analytical Chemistry University of Almeria Almeria, Spain

Beatriz Albero Department of Environment Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria Madrid, Spain

Lorena González Department of Environment Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria Madrid, Spain

Árpád Ambrus Hungarian Food Safety Office Budapest, Hungary

Kit Granby The National Food Institute Technical University of Denmark Søborg, Denmark

Svetlana Bondarenko Department of Environmental Sciences University of California Riverside, California Jane C. Chuang Battelle Columbus, Ohio Adrian Covaci Toxicological Centre University of Antwerp Wilrijk, Belgium Kilian Dill Antara Biosciences Mountain View, California Jay Gan Department of Environmental Sciences University of California Riverside, California

Dimitra Hela Department of Business Administration of Agricultural Products and Food University of Ioannina Agrinio, Greece Susan S. Herrmann The National Food Institute Technical University of Denmark Søborg, Denmark Simon Hird Central Science Laboratory Sand Hutton, York, United Kingdom Ioannis Konstantinou Department of Environmental and Natural Resources Management University of Ioannina Agrinio, Greece

xi

xii

Dimitra Lambropoulou Department of Chemistry University of Ioannina Ioannina, Greece Antonio Martín-Esteban Department of Environment Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria Madrid, Spain Jose Luis Martinez Department of Analytical Chemistry University of Almeria Almeria, Spain Maurice Millet Laboratoire de Physico-Chimie de l’Atmosphère Centre de Géochimie de la Surface Université Louis Pasteur Strasbourg, France Annette Petersen The National Food Institute Technical University of Denmark Søborg, Denmark Mette Erecius Poulsen The National Food Institute Technical University of Denmark Søborg, Denmark Consuelo Sánchez-Brunete Department of Environment Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria Madrid, Spain

Frank J. Schenck Southeast Regional Laboratory U.S. Food and Drug Administration Office of Regulatory Affairs Atlanta, Georgia José L. Tadeo Department of Environment Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria Madrid, Spain Esther Turiel Department of Environment Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria Madrid, Spain Jeanette M. Van Emon National Exposure Research Laboratory U.S. Environmental Protection Agency Las Vegas, Nevada Jon W. Wong Center for Food Safety and Applied Nutrition U.S. Food and Drug Administration College Park, Maryland Guohua Xiong National Exposure Research Laboratory U.S. Environmental Protection Agency Las Vegas, Nevada

1

Pesticides: Classification and Properties José L. Tadeo, Consuelo Sánchez-Brunete, and Lorena González

CONTENTS 1.1 1.2

1.3

1.4

1.5

Introduction ...................................................................................................... 2 Herbicides ........................................................................................................ 4 1.2.1 Amides ............................................................................................... 5 1.2.2 Benzoic Acids .................................................................................... 5 1.2.3 Carbamates......................................................................................... 6 1.2.4 Nitriles................................................................................................ 7 1.2.5 Nitroanilines....................................................................................... 8 1.2.6 Organophosphorus ........................................................................... 10 1.2.7 Phenoxy Acids ................................................................................. 10 1.2.8 Pyridines and Quaternary Ammonium Compounds........................ 12 1.2.9 Pyridazines and Pyridazinones ........................................................ 13 1.2.10 Triazines........................................................................................... 14 1.2.11 Ureas ................................................................................................ 15 1.2.11.1 Phenylureas..................................................................... 15 1.2.11.2 Sulfonylureas .................................................................. 16 Insecticides..................................................................................................... 16 1.3.1 Benzoylureas.................................................................................... 16 1.3.2 Carbamates....................................................................................... 16 1.3.3 Organochlorines ............................................................................... 19 1.3.4 Organophosphorus ........................................................................... 20 1.3.5 Pyrethroids ....................................................................................... 20 Fungicides ...................................................................................................... 23 1.4.1 Azoles .............................................................................................. 23 1.4.2 Benzimidazoles ................................................................................ 23 1.4.3 Dithiocarbamates ............................................................................. 26 1.4.4 Morpholines ..................................................................................... 26 1.4.5 Miscellaneous .................................................................................. 27 Mode of Action.............................................................................................. 28 1.5.1 Herbicides ........................................................................................ 28 1.5.1.1 Amino Acid Synthesis Inhibitors ..................................... 28 1.5.1.2 Cell Division Inhibitors .................................................... 30

1

2

Analysis of Pesticides in Food and Environmental Samples

1.5.1.3 Photosynthesis Inhibitors.................................................... 30 Insecticides......................................................................................... 30 1.5.2.1 Signal Interference in the Nervous System ........................ 30 1.5.2.2 Inhibitors of Cholinesterase................................................ 31 1.5.2.3 Inhibitors of Chitin Synthesis............................................. 31 1.5.3 Fungicides .......................................................................................... 31 1.5.3.1 Sulfhydryl Reagents ........................................................... 31 1.5.3.2 Cell Division Inhibitors ...................................................... 31 1.5.3.3 Inhibitors of Ergosterol Synthesis ...................................... 32 1.6 Toxicity and Risk Assessment....................................................................... 32 References ............................................................................................................... 34 1.5.2

1.1 INTRODUCTION A pesticide is any substance or mixture of substances, natural or synthetic, formulated to control or repel any pest that competes with humans for food, destroys property, and spreads disease. The term pest includes insects, weeds, mammals, and microbes, among others [1]. Pesticides are usually chemical substances, although they can be sometimes biological agents such as virus or bacteria. The active portion of a pesticide, known as the active ingredient, is generally formulated by the manufacturer as emulsifiable concentrates or in solid particles (dust, granules, soluble powder, or wettable powder). Many commercial formulations have to be diluted with water before use and contain adjuvants to improve pesticide retention and absorption by leaves or shoots. There are different classes of pesticides according to their type of use. The main pesticide groups are herbicides, used to kill weeds and other plants growing in places where they are unwanted; insecticides, employed to kill insects and other arthropods; and fungicides, used to kill fungi. Other types of pesticides are acaricides, molluscicides, nematicides, pheromones, plant growth regulators, repellents, and rodenticides. Chemical substances have been used by human to control pests from the beginning of agriculture. Initially, inorganic compounds such as sulfur, arsenic, mercury, and lead were used. The discovery of dichlorodiphenyltrichloroethane (DDT) as an insecticide by Paul Müller in 1939 caused a great impact in the control of pests and soon became widely used in the world. At that time, pesticides had a good reputation mainly due to the control of diseases like malaria transmitted by mosquitoes and the bubonic plague transmitted by fleas, both killing millions of people over time. Nevertheless, this opinion changed after knowing the toxic effects of DDT on birds, particularly after the publication of the book Silent Spring by Rachel Carson in 1962 [2]. At present, due to the possible toxic effects of pesticides on human health and on the environment, there are strict regulations for their registration and use all over the world, especially in developed countries. However, although some progress is achieved in the biological control and in the development of resistance of plants to pests, pesticides are still indispensable for feeding and protecting the world population from diseases. It has been estimated that around one-third of the crop production would be lost if pesticides were not applied.

3

Pesticides: Classification and Properties

Millions of U.S. dollars

32,000 30,000 28,000 26,000 24,000 22,000 20,000 1990 1992 1994 1996 1998 2000 2002 2004 2006

FIGURE 1.1 World market of pesticides since 1990. Values are expressed in millions of U.S. dollars. (From European Crop Protection Association (ECPA) Review 2005–2006, http:==www.ecpa.be.)

Pesticide use has increased 50-fold since 1950 and around 2.5 million tons of industrial pesticides per year are used nowadays. Figure 1.1 shows the time course of pesticide sales during the last years. According to the European Crop Protection Association (ECPA) Annual Report 2001–2002, the main agricultural areas of pesticide usage are North America, Europe, and Asia with 31.9%, 23.8%, and 22.6%, respectively, in 2001 (Figure 1.2). These percentages of pesticide sales are expressed in millions of euros and, although the mentioned regions are the most important agricultural areas in the global pesticide market, their relative position may vary due to changes in the currency exchange rates, climatic conditions, and national policies on agricultural support and regulations. The amount of pesticides applied in a determined geographical area depends on the climatic conditions and on the outbreak of pests and diseases of a particular year. Nevertheless, herbicides are the main group of pesticides used worldwide, followed by insecticides and fungicides (Figure 1.3).

Millions of euros

10,000 8,000 6,000 4,000 2,000 0 North America

Europe

Asia

Latin America

Other

FIGURE 1.2 Regional pesticide sales expressed in millions of euros. (From ECPA Annual Report 2001–2002, http:==www.ecpa.be.)

4

Analysis of Pesticides in Food and Environmental Samples Herbicides

Insecticides

Fungicides

70 60

%

50 40 30 20 10 0 World

USA

Europe

FIGURE 1.3 Distribution of the market (%) per pesticide type. (From Environmental Protection Agency (USEPA), pesticides industry sales and usage, 2001, http:==www.epa.gov= oppbead1=pestsales= and ECPA Annual Report 2001–2002, http:==www.ecpa.be.)

The development of a new chemical as a pesticide takes at present nearly 15 years and around $20 million, and only one compound out of 10,000 compounds initially tested might reach, on average, final commercial production. The registration of a pesticide for its application on a particular crop requires a complete set of data to prove its efficacy and safe use. This normally includes data on physicochemical properties, analytical methods, efficacy, toxicology, ecotoxicology, and fate and behavior in the environment. Residues left on crops after pesticide application have been restricted in developed countries to guaranty a safe food consumption. The maximum residue levels (MRLs) in different foods have been established according to good agricultural practices, the observed toxic effects of the pesticide, and the amount of food consumed. MRLs are normally fixed in relation with the admissible daily intake (ADI) of pesticides, which is the amount of pesticide that can be ingested daily during the whole life without showing an appreciable adverse effect. MRLs are proposed by the Joint FAO=WHO Meeting on Pesticide Residues (JMPR) and recommended for adoption by the Codex Committee on Pesticide Residues [3,4]. In the following sections of this chapter, the main classes of pesticides (herbicides, insecticides, and fungicides) will be described together with their main physicochemical properties and principal uses. These data have been gathered mainly from The Pesticide Manual [5] as well as from the primary manufacture sources [6,7] and other available publications [8,9].

1.2 HERBICIDES The implementation of mechanization in agriculture has increased the ability of human to control weeds and cultivate crops; herbicides have played a main part in this development; and a higher proportion of farmers would be needed if herbicides were not used. Herbicides can be classified as soil- or foliage-applied compounds, which are normally absorbed by roots or leaf tissues, respectively. These compounds can be

5

Pesticides: Classification and Properties

total or selective herbicides. Total herbicides can kill all vegetation, whereas selective herbicides can control weeds without affecting the crop. These chemical substances may be applied at different crop stages, such as presowing and pre- or postemergence, and these different treatments will be used depending on the weed needed to be controlled in a particular crop. The selectivity of a herbicide may depend on a differential plant uptake, translocation, or metabolism, as well as on differences at the site of action. A knowledge of physicochemical properties, that is, vapor pressure (V.p.), octanol=water partition coefficient (Kow, expressed in the logarithmic form log P), and solubility in water allows the fate and behavior of such chemicals in the environment to be predicted. In addition, herbicides can be classified according to their chemical composition. The principal physicochemical properties, together with the field persistence and major uses of representative herbicides, grouped in their main chemical classes, are described later.

1.2.1 AMIDES A large variety of compounds form this group of herbicides, which have the following general formula: R1–CO–N–(R2,R3). The key components of this group are the N-substituted chloroacetamides and the substituted anilides. CH2CH3 COCH2Cl Cl

N

NHCOCH2CH3

CH2OCH3 CH2CH3

Cl Propanil

Alachlor

The chloroacetamides are effective preemergence herbicides for annual grasses and annual broad-leaved weeds but they also have foliar contact activity. In general, these compounds are soil applied and used in various horticultural crops, such as maize, soybean, and sugarcane. These herbicides are normally absorbed by shoots and roots and they are, in general, nonpersistent compounds in soil (Table 1.1).

1.2.2 BENZOIC ACIDS This group is mainly formed by chlorinated derivatives of substituted benzoic acids. CO2H OCH3

Cl

Cl Dicamba

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Analysis of Pesticides in Food and Environmental Samples

TABLE 1.1 Chemical Names and Properties of Amide Herbicides

Common Name Acetochlor C14H20ClNO2 Alachlor C14H20ClNO2 Butachlor C17H26ClNO2 Metolachlor C15H22ClNO2 Propachlor C11H14ClNO Propanil C9H9Cl2NO

IUPAC Name 2-Chloro-N-ethoxymethyl60 -ethylacet-o-toluidide 2-Chloro-20 ,60 -diethyl-Nmethoxymethylacetanilide N-Butoxymethyl-2-chloro-20 ,60 diethylacetanilide 2-Chloro-6-ethyl-N(2-methoxy-1-methylethyl) acet-o-toluidide 2-Chloro-N-isopropyl acetanilide 30 ,40 -Dichloro propionanilide

Vapor Pressure mPa (258C)

Kow log P

Water Solubility mg=L (258C)

Half-Life in Soil (Days)

0.005

4.14

223

8–18

2.0

3.09

170a

1–30

0.24

—

23a

12

4.2

2.9

488

20

10

1.4–2.3

580

4

0.05

3.3

130a

2–3

Sources: Data from Tomlin, C. (Ed.) in The Pesticide Manual, British Crop Protection Council, 2000; http:==ec.europa.eu=food=plant=protection=evaluation=exist_subs_rep_en.htm; http:==www.epa .gov=opprd001=factsheets=; Hornsby, A.G., Wauchope, R.D., and Herner, A.E. in Pesticide Properties in the Environment, Springer-Verlag, New York, 1996; De Liñan, C. in Farmacología Vegetal, Ediciones Agrotecnicas S.L., 1997. a

208C.

The benzoic acid herbicides are known to have growth regulating and auxin activity properties. These compounds are especially used to control deep-rooted perennial weeds and applied as salts or esters (Table 1.2).

1.2.3 CARBAMATES Carbamates are esters of the carbamic acid (R1–O–CO–NR2R3) and together with thiocarbamates (R1–S–CO–NR2R3) represent a broad group of herbicides, frequently applied to soil in preemergence.

NHCO2CH(CH3)2 Propham

[CH3(CH2)2]2 NC(O)SCH2CH3 EPTC

7

Pesticides: Classification and Properties

TABLE 1.2 Chemical Names and Properties of Benzoic Acid Herbicides Common Name Chloramben C7H5Cl2NO2 Chlorthal-dimethyl C10H6Cl4O4 Dicamba C8H6Cl2O3

Vapor Pressure mPa (258C)

IUPAC Name 3-Amino-2,5dichlorobenzoic acid Dimethyl tetrachloroterephthalate 3,6-Dichloro-omethoxybenzoic acid

Water Solubility g=L (258C)

Kow log P

—

—

0.7

0.21

4.28

0.5 3 10

1.67

1.88

6.1

Half-Life in Soil (Days) 14–21

3

33