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Related glossaries include Biomarkers   Drug approvals & clinical trials   Pharmacogenomics

Every day the Food and Drug Administration (FDA) works to balance expeditious access to drugs with concerns for safety, consonant with its mission to protect and advance the public health. The task is all the more complex given the vast diversity of patients and how they respond to drugs, the conditions being treated, and the range of pharmaceutical products and supplements patients use. Reviewers in the Center for Drug Evaluation and Research (CDER) at the FDA must weigh the information available about a drug’s risk and benefit, make decisions in the context of scientific uncertainty, and integrate emerging information bearing on a drug’s risk-benefit profile throughout the lifecycle of a drug, from drug discovery to the end of its useful life. These processes may have life-or-death consequences for individual patients, and for drugs that are widely used, they may also affect entire segments of the population.  Future of Drug Safety: Promoting and Protecting the Health of the Public, National Academies Press, 2007 http://books.nap.edu/openbook.php?record_id=11750&page=1 

adverse drug event ADE:  Recently, another more inclusive term, Adverse Drug Event (ADE) has come into use. According to Bates et al, the term ADE, defined as an injury resulting from medical intervention related to a drug, is preferred since it is more comprehensive and clinically significant than the ADR. (JAMA 1995;274:29- 34). [Saeed A Khan, "Drug Interaction or Adverse Drug Reaction? Confusing Terms", British Medical Journal 10 July, 1998] http://bmj.com/cgi/eletters/316/7149/1930

Google = about 2420 May 8, 2003; about 83,700 Nov 10, 2006

Related terms: adverse drug reaction ADR, drug interaction 

adverse drug reaction ADR:  ADRs may include drug interactions as one of many causes but the reverse is not true. The reader is cautioned regarding usage of drug reaction terms as multiple nearly- similar terms of varying granularity abound. .. "An adverse reaction to a drug has been defined as any noxious or unintended reaction to a drug that is administered in standard doses by the proper route for the purpose of prophylaxis, diagnosis, or treatment(2). However, WHO's original definition of ADR excluded therapeutic failures, intentional and accidental poisoning and drug abuse, as well as adverse events due to medication errors such as drug administration or non- compliance(1) ... Due to non- uniform usage of these terms, it is sometimes difficult to compare various studies and derive incidence rates, etc. for ADRs, and Drug Interactions. Saeed A Khan, "Drug Interaction or Adverse Drug Reaction? Confusing Terms", British Medical Journal 10 July, 1998 http://bmj.com/cgi/eletters/316/7149/1930

Google = about 14,500 May 8, 2003; about 475 Nov 10, 2006

Related terms: adverse drug event ADE, drug interaction 

Bayesian clinical forecasting: Drug approvals and clinical trials

cardiotoxicity: Cardiotoxicity is one of the major forms of toxicity seen in drugs and it accounts for most drug recalls and delays experienced in regulatory approvals. While improvements in experimental and clinical trial design have helped with better detection of cardiac toxicity in drug candidates, the problem still persists and often goes unnoticed until the compound is further along in development or has reached the market. Innovative and sensitive screening techniques and new insights into the cellular mechanisms underlying cardiotoxicity are now facilitating early detection of such adverse events, which should lead to fewer occurrences later in the development cycle.  World Pharma Congress, Cardiotoxicity and Drug Safety: Detecting the Warning Signs of Cardiac Toxicity Early in Discovery, May 12-13, 2008 • Philadelphia, PA

computational toxicology: 

drug interactions: Molecular Medicine

drug safety: Improving products’ effective clinical safety will increase the industry’s fundamental value proposition to patients, healthcare providers, payors and regulators. The program will focus on pharmacovigilance program implementation and specific strategies and approaches to creating true value from a peri- and post-approval drug safety program. Drug safety programs and monitoring and the approach of this conference are not to look at safety in the silos of early-phase safety or post-approval safety but to view safety holistically, across the lifecycle, especially at the transition from approval to broader use in the marketplace. Drug Safety Strategies: Best Practices to Specify, Assess, and Mitigate Risks throughout the Product’s Life Cycle November 13-14, 2007 • Philadelphia, PA

"No matter how good the science is," [Sanket] Agrawal [of Relsys]  says, "when a drug is released we can see only a percentage of the risks. If we want to know everything, it means we would never release a drug." The message should be that "all drugs are chemicals and come with side effects, known and unknown. Pharmaceutical companies need to communicate the benefits [correlated to price] versus the risks...and let people make informed decisions."  New Directions in Drug Safety, BioIT World, ecliniqua, Feb 2007  http://www.bio-itworld.com/archive/eclinica/index_02262007.htm 

CDER [FDA] evaluates the safety profiles of drugs available to American consumers using a variety of tools and disciplines throughout the life cycle of the drugs. We maintain a system of postmarketing surveillance and risk assessment programs to identify adverse events that did not appear during the drug development process. We learn about adverse events through required reporting by companies and through voluntary reports submitted to FDA’s MedWatch program, which together total more than 250,000 reports per year. Staff in the Office of Drug Safety use this information to identify drug safety concerns and recommend actions to improve product safety and protect the public health.  Activities include updating drug labeling, providing more information to the community, implementing or revising a risk management program, and, on rare occasions, reevaluating approval or marketing decisions. Office of Drug Safety, CDER, FDA  http://www.fda.gov/cder/Offices/ODS/default.htm 

Trends in Drug Safety, Molecular Medicine Tri-Conference, March 26-28, 2008 San Francisco CA

Drug Safety Initiative,  FDA http://www.fda.gov/cder/drugSafety.htm  

Narrower term: pharmacovigilance

EMEA: European Agency for the Evaluation of Medicinal Products http://www.emea.eu.

ecotoxicogenomics, ecotoxicology: Genomics categories

ED 50:  Abbreviation for median effective dose. 

evidence- based toxicology: Evidence-based toxicology: a comprehensive framework for causation, Guzelian PS, Victoroff MS, Halmes NC, James RC, Guzelian CP., Hum Exp Toxicol. 2005 Apr;24(4): 161-201 

hepatotoxicity: Hepatotoxicity is the number one cause for drug recalls and new drug refusals based on adverse drug reactions. According to FDA and industry sources hepatotoxicity accounts for ~27% of the drugs withdrawn from the market since 1960 and is responsible for greater than 40% of the clinical phase drug candidate terminations. While new scientific data explaining the underlying cellular mechanisms of drug-induced liver injury (DILI) continue to be published, there is still a dearth of pre-clinical models that could reliably predict a compound’s likelihood to induce hepatotoxicity. Innovative and sensitive in vitro screening assays, improved animal models for toxicity, use of in silico tools for better prediction and effective use of early clinical data are some of the ways by which many companies are now trying to reduce the occurrence of toxicity later in the development cycle. Hepatotoxicity and Drug Safety: Improving Pre-clinical Predictions of Drug Induced Liver Injury, May 13-14, 2008 Philadelphia PA

Wikipedia http://en.wikipedia.org/wiki/Hepatotoxicity  

idiosyncratic toxicity: The primary role of Phase IV postmarketing surveillance is to detect rare or idiosyncratic adverse events that do not manifest in the population sizes common to clinical trials ... While clinical forecasting is aimed at predicting safety and efficacy early int he d3rug development process, rare or idiosyncratic toxicities can only be detected in Phase IV.  There, Phase IV serves as a very important safety net, to catch problems that could not be predicted.  Insight Pharma Reports, Bayesian Forecasting of Phase III Outcomes: The Next Wave in Predictive Tools, June 2007   

Few drug development surprises can be as devastating as toxicity problems that only show up under a combination of conditions as idiosyncratic toxicity. Because of the role of variations in human drug metabolizing enzymes there may only be subtle (or no) evidence of such problems during pre-clinical safety studies. Such problems are also unlikely to show up in all but the largest clinical trials, but if the side effects are serious, it can result in product withdrawal.   

immunogenicity: Drug discovery & development

LD 50:  The dose of a substance that will kill half (50%) of the treated test animals when given as a single dose.  A measure of acute toxicity. [Chemical Hygiene Glossary of Terms, Environment, Health & Safety Lab, Lawrence Berkeley National Laboratory, US]

molecular pharmacology: Pharmacogenomics glossary

molecular toxicology:  The scope [of the Journal of Bichemical and Molecular Toxicology] includes effects on the organism at all stages of development, on organ systems, tissues, and cells as well as on enzymes, receptors, hormones, and genes. The biochemical and molecular aspects of uptake, transport, storage, excretion, lactivation and detoxication of drugs, agricultural, industrial and environmental chemicals, natural products and food additives are all subjects suitable for publication. Of particular interest are aspects of molecular biology related to biochemical toxicology. These include studies of the expression of genes related to detoxication and activation enzymes, toxicants with modes of action involving effects on nucleic acids, gene expression and protein synthesis, and the toxicity of products derived from biotechnology. Journal of Biochemical and Molecular Toxicology, Wiley Periodicals http://www3.interscience.wiley.com/cgi-bin/jabout/38998/ProductInformation.html 

nanotoxicology: Nanoscience glossary

pharmacoepidemiology: The study of the utilization and effects of drugs in large numbers of people. To accomplish this study, pharmacoepidemiology borrows from both pharmacology and epidemiology. About Pharmacoepidemiology, International Society Pharmacoepidemiology, 2004 http://www.pharmacoepi.org/aboutpe.cfm 

pharmacovigilance: The science and activities relating to the detection, assessment, understanding and prevention of adverse effects or any other drug-related problems. The Importance of Pharmacovigilance, WHO 2002  http://www.who-umc.org/defs.html#pvr  

The process of (a) monitoring medicines as used in everyday practice to identify previously unrecognised or changes in the patterns of their adverse effects; (b) assessing the risks and benefits of medicines in order to determine what action, if any, is necessary to improve their safe use; (c) providing information to users to optimise safe and effective use of medicines; (d) monitoring the impact of any action taken.  Medicines Control Agency, UK, Pilot publication scheme, Glossary of terms, 2003 http://www.mca.gov.uk/pilot/app1.htm#A

Related term: postmarketing surveillance  Broader term: drug safety

postmarketing surveillance: At this stage, after a drug has been launched, pharmaceutical companies may conduct further studies of its performance, often examining long- term safety. 

post approval drug safety:  Integrating drug safety knowledge across a compound’s lifecycle, Structured benefit-risk balance: Update on industry initiatives, Risk management in early development: The preclinical/ clinical safety feedback loop, Decreasing liability and improving brand by employing a proactive communication and risk management strategy, The other side of the benefit-risk ratio: Outcomes research as a means of demonstrating product benefit , Leveraging drug registry tools to assess safety and performance , Embracing the shifting paradigm from post- to pre-approval safety. Post Approval Drug Safety, Nov 13- 14, 2007, Philadelphia PA

A new study from Duke University and The University of North Carolina at Chapel Hill estimates that in 2003 the top 20 pharmaceutical manufacturers spent a total of $800 million, or 0.3 percent of sales, on drug safety monitoring following FDA approval. In the same year, pharmaceutical companies spent 15.6 percent of sales on research and development of new drugs. Study examines Pharmaceutical Spending on Post Approval drug safety, Duke University News & Information, 2007   http://www.fuqua.duke.edu/news/faculty/ridley-spending-0306.html 

Broader term: drug safety  Related term: pharmacovigilance

postmarketing surveillance: See under Drug approvals Phase IV/postmarketing surveillance.

predictive ADME: The completion of the Human Genome Project and recent advances in our understanding of the molecular mechanisms of diseases have provided increasing numbers of newly defined biological pathways and networks with potential preventive or therapeutic targets. The development of molecular diversity libraries and screening of these libraries have provided tremendous opportunities to discover new chemical and biological agents for the prevention and treatment of diseases. This created the belief that increasing numbers of new molecular entities would enter clinical testing and would receive approval from the Food and Drug Administration (FDA) to treat human disorders. However, this has not occurred. Many candidate agents are failing during clinical testing because of their unfavorable pharmacokinetic properties, unacceptable adverse effects, or major toxicities, as well as the lack of efficacy.

The safety of each new chemical entity must be demonstrated prior to its entry into clinical trials. Investigational New Drug (IND) applications to the FDA require chemistry, manufacturing, and control information and results from preclinical toxicology studies for the safety of new agents. Results of nonclinical pharmacokinetic studies for defining ADME properties, addressing important safety issues, or assisting the evaluation of toxicology data for investigational new agents are highly desirable in IND submissions. Novel preclinical tools for Predictive ADME-Toxicology RFA Number: RFA-RM-04-023, 2004   http://grants.nih.gov/grants/guide/rfa-files/RFA-RM-04-023.html#PartI 

predictive safety: Unexpected toxicity is the single greatest cause of pipeline attrition. Despite the fact that a typical preclinical safety program will consume about 1,300 rats and 90 dogs, there is no guarantee that the compound will not present safety problems serious enough to warrant termination. Insight Pharma Report  Outlook for Predictive Safety Technologies, 2006

predictive toxicogenomics: A number of novel approaches to toxicology research that have become available over the past five years that are raising optimism for dramatic improvements in the field. Strategic regulatory, and marketplace issues are driving growth of toxicogenomic and predictive toxicology applications. The ability to predict the toxic effects of potential new drugs is crucial to prioritizing compound pipelines and eliminating costly failures in drug development. The inability to accurately predict toxicity early in drug development cost the pharmaceutical industry $8 billion in 2003, approximately one-third the cost of all drug failures. Even when drugs successfully obtain FDA approval and reach the market, they remain vulnerable to costly safety issues. CHA Toxicogenomics and Predictive Toxicology: Market and Business  Outlook report, 2005   

predictive toxicology: an in-depth survey of strategies to characterize chemical structures and biological systems-covering prediction methods and algorithms, sources of high-quality toxicity data, the most important commercial and noncommercial predictive toxicology programs, and advanced technologies in computational chemistry and biology, statistics, and data mining. Predictive Toxicology The Book, CRC Press, 2005 http://www.predictive-toxicology.org/ 

PSURs Periodic Safety Update Report: Drug Approvals Glossary

safety pharmacology: Pharmacology studies can be divided into three categories: primary pharmacodynamic, secondary pharmacodynamic, and safety pharmacology studies. For the purpose of this document, safety pharmacology studies are defined as those studies that investigate the potential undesirable pharmacodynamic effects of a substance on physiological functions in relation to exposure in the therapeutic range and above. ICH Guidance for Industry, S7A Safety Pharmacology Studies for Human Pharmaceuticals,  2001 http://www.fda.gov/cber/gdlns/ichs7a071201.htm

side- effect: The old term "side effect" has been used in various ways in the past, usually to describe negative (unfavourable) effects, but also positive (favourable) effects. It is recommended that this term no longer be used and particularly should not be regarded as synonymous with adverse event or adverse reaction. ICH Topic E 2 A Clinical Safety Data Management: Definitions and Standards for Expedited Reporting, EMEA European Agency for the Evaluation of Medicinal Products CPMP/ICH/377/95, 1994 http://www.emea.eu.int/pdfs/human/ich/037795en.pdf

Related terms: ADE adverse drug effect, ADR adverse drug reaction

susceptibility: This large diversity in responsiveness among individuals to environmental toxicants makes it difficult to determine actual risks, particularly at the low doses to which most people are exposed. Opportunities now exist for studies of genetic susceptibility for cancer and other diseases in which an environmental component can be presumed. Knowledge from such studies could, in the future, allow markers of genetic susceptibility to be incorporated into epidemiologic studies. This, in turn, would permit adjustment of  interpretation of results to account for genetic susceptibility, thus greatly enhancing the sensitivity and power of these studies to detect environmental components of important diseases. Other projects being considered are a nutrition initiative to determine how nutritional status alters disease susceptibility, and development of transgenic mice that carry important environmental response gene. NIEHS Strategic Plan 2000 "Individual susceptibility", National Institute of Environmental Health Sciences, US, March 2000 http://www.niehs.nih.gov/external/plan2000/suscptblty.htm

Susceptibility seems essentially synonymous with predisposition. Are there differences? 

Related terms: toxicogenomics, Genetic testing genetic screening, predisposition test, predictive test, risk communication

systems pharmacology: Pharmacogenomics glossary

systems toxicology: the combination of traditional toxicology methods with new strategies and tools for integrating high-throughput transcriptomics, proteomics, and metabolomics data. The goal is to better understand and predict potential toxicities at an early stage of drug development, so that biopharmas can gain deeper insights into the biology underlying toxicity, and make “go/ no-go” decisions well before committing to further development and clinical trials.  Kurt Zingler, Cross-Omics and Systems Toxicology, BioIT World 6 (9):  25,  Nov 2007  http://www.bio-itworld.com/issues/2007/nov/cross-omics-and-systems-toxicology/  

BEH.201 deals with the chemical and biological analysis of the metabolism and distribution of drugs, toxins and chemicals in animals and humans. The subject focuses on the mechanisms by which drugs and toxins cause therapeutic and toxic responses, as well as the use of metabolism and toxicity as a basis for drug development. MIT Graduate Studies in Applied Biosciences, Biological Engineering Fall 2003  http://stellar.mit.edu/S/course/BE/fa03/be.201/index.html 

Related terms: -Omes & -omics  cross-omics

therapeutic index TI:  The ratio of the LD50 to the effective dose (ED50). How close is the dose which will kill 50% of the tested animals to the dose required for the desired effect in humans? If these two doses are very close to each other, then there is an obvious danger in using the drug with humans. [US Dept. of Justice in the matter of MDMA Scheduling, Docket No. 84- 48, 1986 www.streetdrugs.org] http://www.mninter.net/~publish/mdma.htm

Related terms: ED 50, LD 50 Lethal Dose 50.

tox-chips: Developed at NIEHS [National Institute for Environmental Health Sciences, US], which contains copies, or clones, of about 2,000 of the 80,000 genes in the human body. Millions of  cloned copies of each gene form a nearly invisible dot that is "arrayed" - hence the name - in a grid pattern on the glass slide. The [NIEHS Microarray] center [at Research Triangle Park, NC] also uses an even newer microarray, called the Human ToxChip, containing clusters of each of  12,000 different cloned genes.

Toxic substances produce changes that express, or turn on and off, genes, the center  scientists said, and the chips and the accompanying computer support used to read the slides, take advantage of that linkage.  Initially the new center is evaluating known toxins - for example, chemicals that are known to cause cancer and/or mutations - to build a library or database showing the typical genetic changes that these known poisons produce. Once they have "signature" profiles of how known toxins change genes, the scientists said, they can evaluate other chemicals for potential harm by comparing the gene changes they produce with those made by the known toxins.  NIEHS "Environmental Health Institute to Use Gene Chips to Evaluate Chemicals for Potential Harm to Humans" Feb. 29, 2001  http://www.niehs.nih.gov/oc/news/toxchip.htm

Related terms: Microarrays glossary

toxicity biomarkers:  Biomarkers glossary

toxicity testing: Assays & screening glossary

toxicogenomics: A compendium of gene expression data enhanced by complete proteomic analysis will enable investigators to probe the complexities of the mechanisms of normal genetic and metabolic pathways, and subsequently, to learn how disease occurs when these pathways malfunction. When combined with information on gene/protein groups, functional pathways and networks, and human genetic polymorphisms, these data will confer new knowledge of gene-environment interactions and human health risks. Homepage, NCTR National Center for Toxigenomics, NIEHS National Institute of Environmental Health Sciences, 2005 http://www.niehs.nih.gov/nct/home.htm

An approach to toxicology measuring how people's genomes respond to environmental stressors or toxicants.  Combines genome- wide gene expression profiling with protein expression patterns using bioinformatics to understand the role of gene- environment interactions in disease, understand how chemicals affect the expression of genes, characterize normal genetic and metabolic pathways, and learn how disease occurs when these pathways malfunction. CHA Cambridge Healthtech Advisors, Clinical Genomics: The Impact of Genomics on Clinical Trials and Medical Practice report, 2004

The study of the structure and output of the genome as it responds to adverse xenobiotic exposure. Ulrich RG. The toxicogenomics of nuclear receptor agonists. Current Opinion in Chemical Biology 7(4) 505- 510, August 2003

An emerging discipline that combines expertise in toxicology, genetics, molecular biology, and environmental health to elucidate the response of living organisms to stressful environments. Of particular interest to scientists in the field is the advancement of high- throughput and computational methodologies to study gene and protein expression at all levels, and the application of this knowledge to enhance our understanding and therapeutic management of human illnesses. The promise of toxicogenomics will become a reality as we begin to fully understand how subtle variations in the environment give rise to altered phenotypes that compromise organ and system functions.  NIEHS, EHP Toxicogenomics, Jan. 2003  http://ehp.niehs.nih.gov/txg/docs/2003/111-1T/eds/eds.html

The ability to predict the toxic effects of potential new drugs is crucial to prioritizing compound pipelines and eliminating costly failures in drug development. Toxicogenomics, which deals primarily with the effects of compounds on gene expression patterns in target cells or tissues, is emerging as a key approach in screening new drug candidates because it may reveal genetic signatures that can be used to predict toxicity in these compounds. Insight Pharma Reports Toxicogenomics: The Promise of Safer, Smarter Drug Development  

The hybridization of functional genomics and molecular toxicology. Leming Shi “DNA Microarrays” 1998-2002 http://www.gene-chips.com/

From toxicology + genomics

Google = about 9,650 Sept. 10, 2003; about 27,700 June 7, 2004, about 1,050 Aug. 15, 2005, about 689,000 Oct. 25, 2006, about 567,000 Apr 5, 2007

National Center for Toxicogenomics, NIEHS, US http://www.niehs.nih.gov/nct/home.htm

toxicoinformatics: An emerging scientific discipline that integrates approaches from multidisciplinary fields of bioinformatics, chemoinformatics, computational toxicology, informatics technologies and physiologically- based pharmacokinetic modeling with the objective of knowledge discovery and the elucidation of mechanisms of toxicity. NCTR's Center for Toxicoinformatics, National Center for Toxicological Research, FDA, 2003  http://www.fda.gov/nctr/science/centers/toxicoinformatics/

Google = about 161 Nov. 21, 2003; about 746 Nov 10, 2006, about 775 Apr 4, 2007

toxicokinetics: Process of the uptake of potentially toxic substances by the body, the biotransformation they undergo, the distribution of the substances and their metabolites in the tissues, and the elimination of the substances and their metabolites from the body. Both the amounts and the concentrations of the substances are studied. The term has essentially the same meaning as pharmacokinetics, but the latter term should be restricted to the study of pharmaceutical substances. [IUPAC Compendium]

See also under pharmacokinetics.

toxicology: Can be described, according to a U.S. National Library of Medicine online tutorial, as "the study of the adverse effects of chemicals or physical agents on living organisms." Such effects run the gamut from immediate death to subtle effects that manifest only months or years after exposure. Toxic substances may affect various levels of the body, such as a particular organ, cell type, or biomolecule. 

toxicoproteomics: Toxicoproteomics is the use of global protein expression technologies to better understand environmental and genetic factors, both in episodes of acute exposure to toxicants and in the long-term development of disease. Integrating transcript, protein, and toxicology data is a major objective of the field of toxicogenomics. KB Tomer, DB Merrick, Toxicoproteomics: a parallel approach to identifying biomarkers Environmental Health Perspectives 2003 Aug;111(11): A578- 579.

Google = about 19,100 Nov 5, 2005; about 16,400 Nov 10, 2006, about 13,100 Apr. 5, 2006

toxins:  Integrated Risk Information Systems, US Environmental Protection Agency http://www.epa.gov/iriswebp/iris/index.html

transcriptomics: In the context of toxicology studies, involves assessing changes in transcription initiation, processing, and degradation after chemical exposure using glass and membrane DNA microarrays and low- output tools, such as ribonuclease protection assays and real-time PCR.

xenobiotic: A compound foreign to an organism. From the Greek xenox = foreign, bios = life. [IUPAC Medicinal Chemistry] Principal xenobiotics include drugs, carcinogens and various compounds that have been introduced into the environment by artificial means. IUPAC Bioinorganic

A key term in toxicology (means foreign substance) is used to identify clearly toxic substances, such as lead, or beneficial therapeutic agents, many of which become toxic at elevated dosage levels.  Drugs can generally be characterized as having a nontoxic or beneficial dose, a toxic dose, and a lethal dose. For example, two 650 mg aspirin tablets are usually beneficial, while seven tablets are usually toxic, and 60 tablets can be lethal. Similarly, a blood alcohol level of 0.05% is generally nontoxic, while 0.10% is toxic, and 0.50% can be lethal. However, it is important to note that such levels are averages, and individuals can manifest significant departures from the mean, depending on expression levels of key metabolic enzymes and the presence of polymorphisms that degrade or enhance the activity of these enzymes.

Bibliography
Insight Pharma Reports, Bayesian Forecasting of Phase III Outcomes: The Next Wave in Predictive Tools, June 2007  
Glossary of IRIS [Integrated Risk Information System] Terms, Environmental Protection Agency, 1999, 130+ terms http://www.epa.gov/iris/gloss8.htm
IUPAC, Glossary for toxicokinetics of chemicals, 365 terms. http://www.iupac.org/publications/pac/2004/pdf/7605x1033.pdf  Published Pure & Applied Chemistry 76 (5): 1033-1082, 2004
IUPAC International Union of Pure and Applied Chemistry, GLOSSARY FOR CHEMISTS OF TERMS USED IN TOXICOLOGY Clinical Chemistry Division, Commission on Toxicology, Recommendations. Pure and Appl. Chem., 65 (9):  2003- 2122, 1993. 1200+ definitions.    http://www.iupac.org/reports/1993/6509duffus/index.html
Glossary of terms, Toxicogenomics Research Consortium, NIEHS, 2003 30 plus terms http://www.niehs.nih.gov/dert/trc/glossary.htm 

Alpha glossary index
How to look for other unfamiliar  terms

IUPAC definitions are reprinted with the permission of the International Union of Pure and Applied Chemistry