Strategies for Reducing Drug and Chemical Residues in Food Animals E-Book

Ronald E. Baynes

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 572

Veröffentlichungsjahr: 2014

Beschreibung

Highlighting international approaches; the book details strategies to minimize contamination, residue monitoring programs, and classes of drugs and chemicals that pose contaminant risk in livestock. * Focuses attention on drug and chemical residues in edible animal products * Covers novel computational, statistical, and mathematical strategies for dealing with chemical exposures in food animals * Details major drug classes used in food animal production and their residue risks * Highlights efforts at harmonizing and the differences among areas like US, EU, Canada, Australia, South America, China, and Asia, where the issue of chemical exposures has significant impact on livestock products * Ties veterinary clinical practice and the use of these drugs in food animals with regulatory standards and mitigation practices

Leseprobe

CONTENTS

Cover

Title page

Copyright page

Preface

Contributors

1 Importance of Veterinary Drug Residues

1.1 Introduction

1.2 Veterinary Drug Use in Livestock

1.3 Quality Assurance Programs

1.4 Adverse Human Health Effects of Drug Residues

1.5 Withdrawal Time Determinations

1.6 Antimicrobial Resistance

1.7 Economic Impact of Drug Residues

References

2 Pharmacokinetic Principles for Understanding Drug Depletion as a Basis for Determination of Withdrawal Periods for Animal Drugs

2.1 Introduction

2.2 Basic Pharmacokinetic Principles Underlying Drug Depletion

2.3 The Impact of PK on Drug Depletion

2.4 Factors Influencing ADME

2.5 Conclusion

References

3 Evaluation of Drug Residue Depletion in the Edible Products of Food-Producing Animals for Establishing Withdrawal Periods and Milk Discard Times

3.1 Introduction

3.2 Information Needed for Determination of Withdrawal Periods or Milk Discard Times

3.3 Factors for Consideration in Conducting a Marker Residue Depletion Study

Acknowledgments

References

4 Establishing Maximum Residue Limits in Europe

4.1 Introduction

4.2 Procedure for the Establishment of MRLs

4.3 Scientific Evaluation

4.4 Extrapolation of MRLs

4.5 Prohibited Drugs

4.6 EU Policy on Minor Use and Minor Species

4.7 EU Policy and Legislation on Feed Additives

4.8 Off-Label Use

Acknowledgments

References

5 Methods to Derive Withdrawal Periods in the European Union

5.1 Introduction

5.2 Withdrawal Periods for Meat

5.3 Statistical Method

5.4 Alternative Approach: Decision Rule

5.5 Withdrawal Periods for Milk

5.6 Withdrawal Periods for Eggs

5.7 Withdrawal Periods for Honey

5.8 Extrapolation of Withdrawal Periods

References

6 Population Pharmacokinetic Modeling to Predict Withdrawal Times

6.1 Introduction

6.2 Applications of Population Modeling to Preslaughter Withdrawal Times

6.3 Covariate Analysis

6.4 Benefits to Population-Based Modeling Techniques

6.5 Limitations of Population-Based Modeling Techniques

6.6 Future Applications

6.7 Conclusions

References

7 Physiologically Based Pharmacokinetic Modeling

7.1 Introduction

7.2 Model Development and Validation

7.3 PBPK Applied to Prediction of Drug Residues

7.4 Conclusions

References

8 Residue Avoidance in Beef Cattle Production Systems

8.1 Introduction

8.2 Beef Cattle Production Systems

8.3 Use of Anti-infective Agents in Beef Cattle Production

8.4 Approaches to Minimize the Need for Antimicrobial Drugs

8.5 Approaches to Minimize the Need for Parasiticides

8.6 Approaches to Minimize Residues (Residue Avoidance)

8.7 Quality Assurance Programs

8.8 The Future: Antimicrobial Regulation and the Market for “Antimicrobial-Free” Beef Products

References

9 Residue Avoidance in Dairy Cattle Production Systems

9.1 Prophylactic Use of Drugs in Dairy Cattle

9.2 Therapeutic Use of Drugs in Dairy Cattle

9.3 Prevalence of Drug Residues

9.4 Minimizing Residues in Meat and Milk

References

10 Residue Avoidance in Aquaculture Production Systems

10.1 Introduction

10.2 Environmental Contaminants

10.3 Drug Use as a Source of Residues

10.4 Melamine Adulteration of Aquaculture Feeds: A Case Study

Acknowledgments

References

11 Residue Avoidance in Small Ruminant Production Systems

11.1 Introduction

11.2 Prophylactic Use of Major Drug Classes (e.g., Antibiotics, Antiparasitics) in Goat and Sheep Production Systems in the EU, United States, and Australasia

11.3 Therapeutic Use of Major Drug Classes (e.g., Antibiotics, Antiparasitics) in Goat and Sheep Production Systems

11.4 Prevalence of Drug Residues in Sheep and Goat Meat and Milk

11.5 Approaches to Minimize Antimicrobial Use and Cost of Eliminating Subtherapeutic Use

11.6 Quality Assurance Programs with Special Emphasis on Management of Drug Residues in Goat and Sheep Production Systems

11.7 The Future

References

12 Residue Avoidance in Swine Production Systems

12.1 Introduction

12.2 Prophylactic Use of Drugs in Swine

12.3 Therapeutic Use of Drugs in Swine

12.4 Prevalence of Drug Residues

12.5 Minimizing Residues in Swine

References

13 Confirmatory Methods for Veterinary Drugs and Chemical Contaminants in Livestock Commodities

13.1 Introduction and Essential Concepts

13.2 Instrumentation and Techniques

13.3 Method Development, Validation, and Official Guidelines

13.4 Selected Recent Publications for Confirmation of Veterinary Drugs or Organic Contaminants in Food Animal Products and Feed

13.5 Conclusion and Future Perspective

Acknowledgments

References

14 The Food Animal Residue Avoidance Databank

14.1 Origins of FARAD

14.2 The Role of FARAD

14.3 Access to Regulatory Drug Information via the FARAD Website

14.4 Expert-Mediated Consultations by FARAD

14.5 FARAD Publications and Presentations

14.6 Global FARAD

References

Further Reading

15 Risk Management of Chemical Contaminants in Livestock

15.1 Introduction

15.2 Heptachlor

15.3 Dioxin

15.4 Melamine

15.5 Radioactive Contamination and Management Consideration

15.6 By-Products of Fracking

References

Index

End User License Agreement

List of Tables

Chapter 04

Table 4.1 Potential MRL extrapolations within classes of animals

Chapter 05

Table 5.1 Distribution of TTSC values per animal

Chapter 07

Table 7.1 Comparison between PBPK models and classical compartmental analysis

Table 7.2 Common mass balance equations found in both flow-limited and diffusion-limited PBPK models

Table 7.3 Comparison of parameter values in a sulfamethazine PBPK model for swine for both individual and population estimation

Chapter 08

Table 8.1 Bacterial and parasitic conditions for which at least one injectable, oral, or feed additive drug is approved in the United States for beef cattle

Table 8.2 A comparison of the U.S. MRL to the test detection limits of

Bacillus megaterium

,

Bacillus stearothermophilus

, and

Bacillus subtilis

for FDA-approved cattle antibiotics

Table 8.3 Examples of quality assurance programs websites

Chapter 09

Table 9.1 Antimicrobial use in dairy cows in the United States

Table 9.2 Drugs currently prohibited from extralabel use in dairy cattle in the United States

Table 9.3 Drugs approved for lactating dairy cattle in the United States along with meat and milk withholding times

Table 9.4 Drugs currently prohibited from extralabel use in dairy cattle in the EU

Table 9.5 Summary of drug residue data from milk samples tested in the United States between 2003 and 2009

Table 9.6 Summary of drug residue data from milk samples tested in the United States between 2003 and 2012

Table 9.7 Summary of drug residue data from cull dairy cows tested in the United States between 2004 and 2011

Chapter 11

Table 11.1 FARAD calls on sheep and goats (January 1, 2005 to January 1, 2007)

Table 11.2 “Commonly used drugs” with an indication of use for “prevention” or “control”

Table 11.3 Total number of samples tested in 2008 by the FSIS in the United States for veterinary drug, food additive, and environmental contaminant residues, as well as kidney samples tested for antibiotic residues

Table 11.4 Results of scheduled sampling in (a) 2008 and (b) 2007 in the United States

Table 11.5 Results of sheep and goat residue samplings in Australia for 2007–2008

Table 11.6 Recommendations for avoiding drug residues in goat milk

Chapter 12

Table 12.1 Examples of therapeutic antimicrobials approved for use in swine from 10 drug classes

Table 12.2 Examples of antiparasitic drugs approved for use in all swine classes

Table 12.3 Summary of U.S. FSIS drug residue monitoring in 2010 of three swine classes

Table 12.4 FSIS domestic scheduled sampling for 2013

Chapter 13

Table 13.1 Four types of regulatory methods for residue analysis

Table 13.2 Parameters to evaluate performance of qualitative methods

Table 13.3 Summary of confirmation criteria for various MS type and acquisition modes in CVM GFI-118

Table 13.4 Foods program key validation parameter requirements for chemical methods

Table 13.5 Suitable confirmatory methods for organic residues or contaminants (“Table 1” in 2002/657/EC)

Table 13.6 Assignment of IP to various types of MS-derived signals (“Table 5” in 2002/657/EC)

Table 13.7 Maximum permitted tolerances for relative ion intensities using a range of mass spectrometric techniques (“Table 4” in 2002/657/EC)

Table 13.8 Examples of the number of IPs earned for a range of techniques and combinations thereof (“Table 6” in 2002/657/EC;

N

or

n

is a positive integer)

Table 13.9 Confirmation criteria for GC-MS- or LC-MS-based methods (for unit resolution MS)

Table 13.10 Selected examples of LC-MS-based confirmatory methods

Chapter 14

Table 14.1 Residue-related inquiries by agent or drug class to FARAD during 2012

List of Illustrations

Chapter 02

Figure 2.1 A two-compartment body model with first-order absorption.

Chapter 04

Figure 4.1 How the ADI is divided between the target tissues.

Chapter 05

Figure 5.1 Example plot of withdrawal period calculation.

Chapter 06

Figure 6.1 Model of a population approach (Phoenix WinNonMix 6.0) to estimate the steady state plasma concentrations of a medication given to a population of swine medication via at will dosing.

Figure 6.2 Simulation of a population of animals when the pharmacokinetic elimination profile is emphasized over the therapeutic profile in Figure 6.1 (Phoenix WinNonMix 6.0).

Figure 6.3 Graphical results of a PK modeling including covariates (a) compared to model without covariates (b).

Figure 6.4 Plot of residuals for a model versus the concentration for a covariate. The residuals from this model are systematically too low for the data, suggesting that the covariate should be investigated further.

Chapter 07

Figure 7.1  Schematic diagram of a simplified PBPK model. Arrows represent mass transfer via blood flow or elimination.

Figure 7.2 Schematic diagram of a more complicated PBPK model. Arrows represent mass transfer via blood flow or elimination.

Figure 7.3 Schematic diagram of a representative PBPK model designed for food residue avoidance. Tissue blocks represent common edible tissues. Arrows represent mass transfer via blood flow or elimination.

Figure 7.4 Schematic diagram of a tissue block containing multiple subcompartments. Arrows represent mass transfer either via blood flow, in equilibrium within the subcompartment, or through elimination.

Figure 7.5 Example sensitivity analysis for relative change in plasma concentration over time when hepatic clearance, protein binding, and renal clearance are individually altered.

Figure 7.6 Examples of various different validation techniques including predicted versus observed concentration regression (a), standard residual plot (b), and direct comparison of simulated concentration–time curves to observed data (c). Dots represent observed data points. Lines represent model simulations.

Figure 7.7 Schematic diagram of a PBPK model designed for the prediction of drug residues of sulfamethazine in swine.

C

, sulfamethazine concentration; IV, intravenous dose;

K

a

, rate of absorption;

K

st

, rate of gastric emptying; Met, metabolite; PO, oral dose;

Q

, blood flow;

V

, tissue volume.

Figure 7.8 PBPK model simulations for sulfamethazine in edible tissues after an oral dose of 100 mg/kg given to swine. Solid line, kidney; large dash, plasma; dot–dash, liver; dot, adipose; dot–dot–dash, muscle; horizontal line, tolerance limit of 0.1 ppm.

Figure 7.9 Population distribution of time for muscle concentrations of sulfamethazine to fall below tolerance (0.1 ppm) after the label oral dose (237.6 mg/kg on day 1 followed by 118.8 mg/kg for 3 more days) using a Monte Carlo analysis of 1000 simulations.

Figure 7.10 Schematic diagram of a PBPK model of melamine in rats and swine. Arrows represent mass transfer through blood flow or elimination into urine. GIP, isolated gastrointestinal perfusion dose; IV, intravenous dose; PO, oral dose; SI, small intestine.

Figure 7.11 Plasma concentration–time simulation for melamine in swine after a single bolus IV dose. Squares represent observed data from an independent study. .

Figure 7.12 Concentration–time curves for edible tissues of the kidney (solid line), liver (dashed line), and plasma (dotted line) after twice daily administration of 5.12 mg/kg orally for 7 days. Horizontal line represents safe level of 50 ppb. .

Chapter 08

Figure 8.1 Beef cow and calf in Midwestern United States.

Figure 8.2 Beef feedlot in Nebraska, United States.

Figure 8.3 Prudent antimicrobial drug use recommendations, from the National Cattlemen’s Beef Association.

Figure 8.4 LAST using urine. Top right swab demonstrates inhibition suggesting the presence of an antimicrobial drug.

Figure 8.5 Combination electronic and plastic ear tag for identification of cattle.

Figure 8.6 Computer and software for record keeping.

Figure 8.7 Lesion from intramuscular injection.

Figure 8.8 Read the drug label to ensure proper dose and route of administration of drugs and vaccines.

Chapter 09

Figure 9.1 A sample treatment record to be kept on dairy farms. Records should contain the date of treatment, animal identification, drug used, dosage and route of administration, individual who administered the drug, and withdrawal time for meat and milk.

Chapter 11

Figure 11.1 Meat consumption in the United States in 2008. The data in the graph represents the percentage of the total meat production based on total dressed weight of the slaughtered animals .

Chapter 13

Figure 13.1 Typical steps in regulatory method development, validation, and routine use.

Figure 13.2 Essential elements of confirmatory methods.

Chapter 14

Figure 14.1 Home page of the FARAD website. The interactive FARAD website (www.farad.org) provides access to the latest regulations for approved food animal drugs as well as many user-defined search options and tools.

Figure 14.2 Home page of VetGRAM. The VetGRAM is an intuitive online search interface located on the FARAD website (http://www.farad.org/vetgram/search.asp). VetGRAM allows users to conduct user-defined searches of all U.S. drug approvals for food-producing animals.

Figure 14.3 Mobile phone VetGRAM application for the Android operating system. In the Spring of 2013, FARAD launched a free mobile app for use on touchscreen mobile devices that use the Android operating system, including smartphones and tablet computers. The new product is a native app with an updatable database that provides users with full access to key information about all FDA-approved drugs for use in food-producing animal species.

Figure 14.4 Screen capture from Web portal for submission of residue-related questions to FARAD. The U.S. FARAD online request system is operated at UCD and provides an easy conduit for veterinarians to submit questions about accidental chemical exposures or ELDU in food-producing animals. This service as well as the toll-free hotline is a free service for licensed U.S. veterinarians.

Figure 14.5 Submission statistics by species for questions submitted to FARAD. The categories cover a 5-year period (2008–2012) and are reported as a percentage of all submissions rather than numbers of animals involved.

Figure 14.6 WDI Lookup Tool on the FARAD website. This online searchable database of FARAD-recommended safe WDIs is limited to a select group of animal drugs that are approved but commonly used in an extralabel manner. The WDI tool was launched in late 2010 and currently includes recommendations for 31 drugs in major and minor food animal species. The recommendations are based on analyses of peer-reviewed published data and help fulfill the AMDUCA mandate to veterinarians regarding ELDU.

Chapter 15

Figure 15.1 Plasma concentration–time profiles of ME in swine given 6 mg/kg ME IV.

Guide

Cover

Table of Contents

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STRATEGIES FOR REDUCING DRUG AND CHEMICAL RESIDUES IN FOOD ANIMALS

International Approaches to Residue Avoidance, Management, and Testing

Edited by

RONALD E. BAYNES

North Carolina State University

Raleigh, NC, USA

JIM E. RIVIERE

Kansas State University

Manhattan, KS, USA

Copyright © 2014 by John Wiley & Sons, Inc. All rights reserved

Published by John Wiley & Sons, Inc., Hoboken, New JerseyPublished simultaneously in Canada

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, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, [phone], fax [phone], or on the web at www.copyright.com. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, [phone], fax [phone], or online at http://www.wiley.com/go/permissions.

Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives or written sales materials. The advice and strategies contained herein may not be suitable for your situation. You should consult with a professional where appropriate. Neither the publisher nor author shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages.

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Library of Congress Cataloging-in-Publication Data:

Strategies for reducing drug and chemical residues in food animals : international approaches to residue avoidance, management, and testing / edited by Ronald E. Baynes, North Carolina State University, Raleigh, North Carolina, USA, Jim E. Riviere, Kansas State University, Manhattan, Kansas, USA.  pages cm Includes bibliographical references and index.

 ISBN 978-0-470-24752-5 (cloth)1. Food animals–Feeding and feeds–Contamination. 2. Food animals–Nutrition. 3. Veterinary drug residues. 4. Animal nutrition. I. Baynes, Ronald, editor of compilation. II. Riviere, J. Edmond (Jim Edmond) editor of compilation. SF95.S88 2014 636.08′5–dc23

2014011452

Preface

The focus of this book is to present strategies that are utilized to reduce drug and chemical residues in food from livestock production, and also to present some of the newer technologies and theories that will shape how drug residues will be managed in the future. One of the novel features of this book is that it will tie in the realities of veterinary clinical practice and the use of these drugs in food animals with regulatory standards and mitigation practices.

The first half of this book focuses on strategies that are part of public policy in national and international agencies and how these agencies assess the toxicology of veterinary drugs and contaminants. This involves some discussion of how to compute safe levels (tolerances and maximum residue levels, MRLs) of these drugs and chemicals in meat and milk so that human health is not adversely affected. This section highlights the efforts at harmonization as well as differences across such jurisdictions as United States, European Union, Canada, Australia, South America, China, and Asia, where this issue has a significant impact on the trade of livestock products. This section also focuses on novel computational strategies that incorporate more statistical and mathematical approaches that are now possible with the advent of modern computers to derive safe withdrawal times. These chapters provide the reader with a general introduction to basic pharmacokinetic principles, especially those principles that are applicable in subsequent chapters in this section as it pertains to estimating a safe withdrawal time for veterinary drugs and contaminants. PK parameters and their derivation are defined in the Chapter 1. These chapters also focus on how the WDT is established in US vs. EU.

The second half of this book focuses on the use of major drug classes in livestock food animal production systems and the drugs most likely targeted for regulatory policy, pharmacokinetic modeling, and chemical residue monitoring. Each chapter in this section will be focused on subtherapeutic (feed) and therapeutic use of drugs in major livestock species such as dairy and beef cattle, swine, poultry, fish aquaculture, and small ruminant production systems. Each production system requires species-specific management practices of drug residues. Quality assurance programs are discussed for each major species with regards to species-specific management practices for controlling drug residues as well as subtherapeutic versus therapeutic drug use in livestock, and how these practices are related to the emergence of antimicrobial resistance.

Contributors

Glen Almond, DVM, PhDDepartment of Population Health and PathobiologyCollege of Veterinary MedicineNorth Carolina State UniversityRaleigh, NC, USA

Kevin Anderson, DVM, PhD, Dipl. ABVPDepartment of Population Health and PathobiologyCollege of Veterinary MedicineNorth Carolina State UniversityRaleigh, NC, USA

Reha Azizoglu, PhDDepartment of Population Health and PathobiologyCollege of Veterinary MedicineNorth Carolina State UniversityRaleigh, NC, USA

Ronald E. Baynes, DVM, PhDDepartment of Population Health and PathobiologyCollege of Veterinary MedicineNorth Carolina State UniversityRaleigh, NC, USA

Jennifer Buur, DVM, PhD, Dipl. ACVCPCollege of Veterinary MedicineWestern University of Health SciencesPomona, CA, USA

Isaura Duarte, DVMEuropean Medicines AgencyLondon, UK

Virginia Fajt, DVM, PhD, Dipl. ACVCPDepartment of Veterinary Physiology and PharmacologyCollege of Veterinary Medicine and Biomedical SciencesTexas A&M UniversityCollege Station, TX, USA

Kornelia Grein, PhDEuropean Medicines AgencyLondon, UK

Dee Griffin, DVM, PhDGreat Plains Veterinary Education CenterUniversity of NebraskaLincoln, NE, USA

Hui Li, PhDDivision of Residue Chemistry, Office of ResearchCenter for Veterinary Medicine, FDALaurel, MD, USA

Sharon E. Mason, DVM, PhDDepartment of Biological SciencesCampbell UniversityBuies Creek, NC, USA

Sanja Modric, D.V.M., PhDCenter for Veterinary MedicineFood and Drug AdministrationRockville, MD, USA

Renate Reimschuessel, V.M.D., PhDVeterinary Laboratory Investigation and Response NetworkCenter for Veterinary Medicine, FDALaurel, MD, USA

Jim E. Riviere, DVM, PhD, DSc(hon), ATSDepartment of Anatomy and PhysiologyCollege of Veterinary MedicineKansas State UniversityManhattan, KS, USA

G. JohanSchefferlie, BSc, MScVeterinary Medicines UnitMedicines Evaluation BoardUtrecht, the Netherlands

StefanScheid, PhDFederal Office of Consumer Protection and Food Safety (BVL)Berlin, Germany

Geof Smith, DVM, PhD, Dipl. ACVIMDepartment of Population Health and PathobiologyCollege of Veterinary MedicineNorth Carolina State UniversityRaleigh, NC, USA

Lisa Tell, DVM, Dipl. ABVP, Dipl. ACZVDepartment of Medicine and EpidemiologyUniversity of CaliforniaDavis, CA, USA

Thomas W. Vickroy, PhDDepartment of Physiological Sciences, College of Veterinary MedicineUniversity of FloridaGainesville, FL, USA

Dong Yan, PhDDivision of Human Food Safety, Office of New Animal Drug EvaluationCenter for Veterinary Medicine, United States Food and Drug AdministrationRockville, MD, USA

1Importance of Veterinary Drug Residues

Ronald E. Baynes1 and Jim E. Riviere2

1Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA

2Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA

1.1 Introduction

Food animal production over the last 50–60 years has significantly increased with the implementation of modern genetics, breeding, husbandry, and nutrition. During this same time period, livestock producers have relied on the use of veterinary drugs as one of several strategies to ensure economic viability of the industry. This need for increased use of veterinary drugs, and especially antimicrobial drugs, has been linked to changes in standard livestock practices where the objective is to increase feed and space efficiency and to a need to generate greater quantities of meat, milk, and egg products in an ever increasing competitive global market. While the consumer appreciates the need to increase livestock production and generate reliable and affordable animal-derived products, this is tempered by the consumers’ requirement that the food items be “free” of drugs or chemicals introduced in the production system. The wide availability of related information via the Internet has exposed the consumer to useful facts but all too often to controversial statements and hypotheses with very little factual support from the scientific literature regarding the prevalence of drug residues in our food, how veterinary drugs are used, and what safeguards are implemented to reduce these residues. This introductory chapter will briefly review the role of drugs in modern livestock production, quality assurance programs, adverse human health effects of drug residues, and economic impact of these residues to the livestock industry.