ENVIRONMENTAL TOXICOLOGY

Subject abbreviation: ENTX

Sarjeet S. Gill, Ph.D., Chair and Program Director  

Program Office, 5429 Boyce Hall

Professors:

Michael E. Adams, Ph.D.
Neurosciences
(Entomology and Neuroscience)

Janet T. Arey, Ph.D.
Atmospheric Chemistry
(Environmental Sciences)

Roger Atkinson, Ph.D.
Atmospheric Chemistry
(Environmental Sciences)

Nancy E. Beckage, Ph.D.
Biochemistry and Endocrinology
(Entomology)

Craig V. Byus, Ph.D.
Pharmacology
(Biomedical Sciences)

Andrew C. Chang, Ph.D.
Agricultural Engineering
(Environmental Sciences)

Michael D. Coffey, Ph.D.
Phytophthora Taxonomy and Genetics
(Plant Pathology)

Donald A. Cooksey, Ph.D.
Bacterial Copper Resistance
(Plant Pathology)

Carl F. Cranor, Ph.D.
Regulation of Toxic Substances
(Philosophy)

Michael F. Dunn, Ph.D.
Enzymology/Physical Biochemistry
(Biochemistry)

Joseph W. Eckert, Ph.D.
Mechanism of Fungicide Action
(Plant Pathology)

Walter J. Farmer, Ph.D.
Soil Chemistry
(Environmental Sciences)

Dennis D. Focht, Ph.D.
Soil Microbiology
(Plant Pathology)

Sarjeet S. Gill, Ph.D.
Toxicology
(Entomology)

David A. Johnson, Ph.D.
Molecular Pharmacology
(Biomedical Sciences)

William A. Jury, Ph.D.
Soil Physics
(Environmental Sciences)

Mary Lou Oster-Granite, Ph.D.
Neurogenetics
(Biomedical Sciences)

James J. Sims, Ph.D.
Chemistry of Natural Products
(Plant Pathology)

Prudence Talbot, Ph.D.
Cell Biology
(Biology)

Marylynn V. Yates, Ph.D.
Environmental Microbiology
(Environmental Sciences)

Professors Emeriti:

Charles E. Castro, Ph.D.
Chemistry
(Nematology)

George P. Georghiou, Ph.D.
Toxicology/Insecticide
(Entomology)

J. Brian Mudd, Ph.D.
Plant Biochemistry
(Botany and Plant Sciences)

William F. Spencer, Ph.D.
Soil Chemistry
(Environmental Sciences)

Associate Professors:

David E. Crowley, Ph.D.
Environmental Microbiology
(Environmental Sciences)

David A. Eastmond, Ph.D.
Toxicology
(Entomology)

Andrew J. Grosovsky, Ph.D.
Molecular Carcinogenesis
(Entomology)

Ashok K. Mulchandani, Ph.D.
Chemical Engineering
(College of Engineering)

David R. Parker, Ph.D.
Soil Chemistry
(Environmental Sciences)

Assistant Professors:

Wilfred Chen, Ph.D.
Chemical Engineering
(College of Engineering)

Margarita C. Curras, Ph.D.
Neuroscience
(Neuroscience)

Marc A. Deshusses, Ph.D.
Environmental Biotechnology
(College of Engineering)

Manuela M. Martins-Green, Ph.D.
Cell and Developmental Biology
(Biology)

Rajesh K. Mehra, Ph.D.
Metal Toxicology
(Entomology)

Frances M. Sladek, Ph.D.
Molecular Cell Biology
(Entomology)

Paul J. Ziemann, Ph.D.
Atmospheric Chemistry
(Environmental Sciences)

**

GRADUATE PROGRAM  

The Graduate Program in Environmental Toxicology is an interdepartmental program with participating faculty from the Departments of Biochemistry, Biology, Chemistry, College of Engineering, Entomology, Plant Pathology, and Environmental Sciences as well as scientists from the Division of Biomedical Sciences and the Air Pollution Research Center.

The goal of the program is to train toxicologists capable of directing research in areas of environmental toxicology. Areas of specialization include (a) biochemical toxicology and (b) chemical toxicology. To attain this goal, a three-tiered curriculum has been designed whereby students will be expected to complete

1. A core of courses in environmental toxicology: ENTX 200, ENTX 201, ENTX 201L, ENTX 202, ENTX 270, and either ENTX 200L or ENTX 203

2. A selection of elective courses in environmental toxicology and other relevant fields chosen in consultation with the student's major professor and the Guidance Committee in order to develop depth in particular areas of specialization

3. Research training in specific areas of environmental toxicology

The program will stress the importance of innovative and independent laboratory research as the major component of the student's education. Two years is the normative time for completion of the M.S. (Plan I) program; five years (15 quarters) is the normative time required to complete the Ph.D. program.

For admission into the graduate program in Environmental Toxicology, a student must have a Bachelor of Arts or Science degree from an accredited institution and an academic record which satisfies the minimum admission standards established by the Graduate Division, University of California, Riverside. In addition, results of the Graduate Record Examination (GRE) General Test scores (verbal, quantitative, analytical) tests must be submitted to the program by all applicants at the time of application. Although no specific undergraduate degree specialization is required, applicants for the program should have adequate backgrounds in the basic physical sciences such as chemistry, physics, and mathematics as well as in the biological sciences.

Normally, students admitted to regular standing will have satisfied all prerequisite course work. Under special circumstances, students who have not completed all undergraduate requirements may be admitted provided that these deficiencies are corrected within the first year of graduate study. Deficiencies must be corrected by taking the appropriate course work if undergraduate or other previous training has not included equivalent courses to the following: BIOL 005A-BIOL 005B, BCH 110A-BCH 110B, BCH 110C or BIOL 107, CHEM 001A-CHEM 001B-CHEM 001C, CHEM 005, CHEM 112A-CHEM 112B-CHEM 112C, PHYS 002A, PHYS 002B, PHYS 002C, MATH 009A-MATH 009B, STAT 100A-STAT 100B or STAT 120A-STAT 120B, CHEM 109 or CHEM 110A, CHEM 110B or CHEM 109 and BCH 184. Students who meet all the undergraduate entrance requirements should be able to complete the core Environmental Toxicology requirements in the first year and most electives by the end of the second year.

All Environmental Toxicology students will participate in laboratory rotation through enrollment in ENTX 201L. Students spend time in one laboratory per quarter familiarizing themselves with research techniques utilized in the laboratory of an Environmental Toxicology faculty member. Rotation laboratories are chosen in consultation with the Graduate Advisor and individual faculty members. Students may enroll in up to three quarters of laboratory rotation before declaring a major professor. Students who wish to declare a major professor after one quarter are not required to enroll for additional laboratory rotation. The major professor serves as Chair of the student's Guidance and Dissertation Committees.

Each Environmental Toxicology graduate student will establish a Guidance Committee which will participate in the annual student progress evaluation procedure and advise the student on curriculum and research. The Committee consists of the major professor plus at least two other faculty, one of whom must be a member of the Environmental Toxicology Program. Each student, in consultation with the major professor, will nominate the members of the Guidance Committee. The Guidance Committee must be named by the end of the quarter in which the student selects a major professor. The composition of the Guidance Committee must be approved by the Curriculum and Student Affairs Committee.

MASTER'S DEGREE

Students enrolling in the Master's degree program must meet the requirements for the Plan I of the UCR Graduate Council, take core courses as described above, and submit an acceptable thesis.

Thirty-six (36) units are required of which 24 must be in graduate-level courses. No more than 12 units of ENTX 290, ENTX 297, and ENTX 299 may be used to satisfy the unit requirement. All students must enroll in the Environmental Toxicology seminar (ENTX 270) each quarter although no more than 3 units from seminar courses can be accrued towards degree credit. A final oral examination will consist of an open research seminar, presented by the candidate and advertised to all the students and faculty in the Environmental Toxicology Program. Following the seminar, the student will be subject to questioning by the Guidance Committee on the thesis research and on matters related to the general field of the thesis research.

DOCTORAL DEGREE

Students must meet general University requirements of the Graduate Division as found in the Graduate Studies section of this catalog. Beyond the required core sequence, all students must enroll in the Environmental Toxicology seminar (ENTX 270) and complete a program of courses to be approved by the Guidance Committee. All course work schedules will be submitted to the Graduate Advisor for approval. The Ph.D. degree will be awarded upon passing the preliminary and qualifying examinations and demonstrating an ability to do original research by preparation and submission of an acceptable dissertation.

The Preliminary Examination is a standardized, written test generally offered once a year prior to the beginning of the fall quarter. Students will normally take the Preliminary Examination following the completion of the core curriculum. The Preliminary Examination must be satisfactorily completed in order to enroll for the seventh academic quarter in the Ph.D. program.

The Preliminary Examination consists of questions related to environmental, organismal and suborganismal aspects of toxicology. These questions are designed to test the student's ability to synthesize and integrate concepts in toxicology, rather than merely reiterate the material covered in the Environmental Toxicology core curriculum.

The examination is administered by a committee consisting of the faculty members involved in teaching the core curriculum. Based on the results of this examination, the committee will recommend appointment of a faculty qualifying committee, additional course work in specific area(s) of weakness, transfer to a terminal Master's program, or total withdrawal from the program. In exceptional circumstances, the preliminary examination can be taken a second time.

The qualifying examination is an oral examination conducted by the qualifying committee. The qualifying committee, appointed by the Graduate Dean from nominations made by the faculty, will be composed of the student's major professor and four additional members, one of whom must be from outside the Graduate Environmental Toxicology group. The oral examination will include the student's area of specialization and research field as well as general subjects at the discretion of the Qualifying Committee. The qualifying examination must be successfully completed by the end of the ninth quarter of full time enrollment in the Ph.D. program. Under exceptional circumstances, the qualifying examination may be taken a second time. Upon successful completion of the qualifying examination, the student will be advanced to candidacy.

A dissertation committee composed of at least three members will be appointed by the Graduate Dean shortly after advancement to candidacy. A dissertation acceptable to all committee members must be submitted based upon independent, original research.

Before approval of the dissertation, students are required to orally present their research at a thesis defense seminar. The seminar must be advertised to the campus community and is open to all who wish to attend. Following the seminar, the student will be subject to questioning by the dissertation committee on the thesis research and on matters related to the general field of the thesis research.

UPPER-DIVISION COURSES  

ENTX 101.
Fundamental Toxicology. (4) W

Lecture, three hours; discussion, one hour. Prerequisite(s): BIOL 005A, BIOL 005B, CHEM 112A-CHEM 112B-CHEM 112C; or consent of instructor. Fundamental concepts relating to the adverse effects of chemical agents. Topics covered include dose-response relationships, absorption, distribution, metabolism, excretion, mechanisms of toxicity, and the effects of selected environmental toxicants on various organ systems. Characterization and assessment of risks are also covered. Mehra.

ENTX 135.
Chemistry of the Clean and Polluted Atmosphere. (4) W

Lecture, three hours; discussion, one hour. Prerequisite(s): CHEM 112A-CHEM 112B or consent of instructor; ENSC 102 recommended. Structure of the troposphere and stratosphere; formation of atmospheric ozone; tropospheric NOx chemistry; methane oxidation cycle; phase distributions of chemicals; wet and dry deposition; chemistry of volatile organic compounds; formation of photochemical air pollution; modeling of air pollution and control strategies; stratospheric ozone depletion and global warming. Cross-listed with CHEM 135 and ENSC 135. Atkinson.

ENTX 136.
Chemistry of Natural Waters. (4) S

Lecture, three hours; discussion, one hour. Prerequisite(s): CHEM 005 with a grade of "C-" or better or SLSC 104 with a grade of "C-" or better or consent of instructor. Introduction to processes controlling the chemical composition of natural waters. Topics include chemical equilibria, acid-base and coordination chemistry, oxidation-reduction reactions, precipitation-dissolution, air-water exchange, and use of equilibrium and kinetic models for describing marine nutrient, trace metal, and sediment chemistry. Cross-listed with CHEM 136 and ENSC 136. Ziemann.

ENTX 150.
Cancer Biology. (4) S

Lecture, three hours; discussion, one hour. Prerequisite(s): BCH 110C or BIOL 107; BIOL 111 is recommended (may be taken concurrently). The origin, development, and treatment of cancer are explored with emphasis on molecular mechanisms. Topics such as oncogenes, tumor suppressors, cell cycle and differentiation, AIDS, and heredity and environmental factors in the development of cancer are covered. Cross-listed with BIOL 150. Sladek.

ENTX 154.
Risk Assessment. (4) S

Lecture, three hours; discussion, one hour. Prerequisite(s): ENTX 101, and either STAT 100A or STAT 105 or STAT 120A; or consent of instructor. An introduction to the basic principles and methods by which health risks associated with exposure to chemical and physical agents are determined. Topics include hazard identification, dose response and exposure assessments, as well as risk characterization and management. Eastmond.

GRADUATE COURSES  

ENTX 200.
Fate and Transport of Chemicals in the Environment. (4) S

Lecture, four hours. Prerequisite(s): CHEM 109 or CHEM 110B; CHEM 112A-CHEM 112B-CHEM 112C; or consent of instructor. Identification of toxicants and their sources in the environment; equilibrium partitioning of chemicals in the environment (between air, water, soil, sediment, and biota) using physico-chemical properties; transport and chemical transformations of chemical compounds in air, water, and soil media. Includes case studies of fate and transport of selected toxic chemicals. Cross-listed with CHEM 246. Atkinson.

ENTX 200L.
Analysis and Identification of Environmental Toxicants. (3) W

Lecture, one hour; laboratory, six hours. Prerequisite(s): ENTX 200, CHEM 125 (lecture portion only); or consent of instructor. Provides laboratory experience in specialized methods of identification and analysis of toxic organic compounds in gaseous, aqueous, and soil media. Methods of sample collection and extraction are presented. Students utilize both gas and liquid chromatographic techniques. Toxicant analysis by gas chromatography (GC), GC/mass spectrometry, and GC/Fourier transform infrared spectroscopy is emphasized. Arey.

ENTX 201.
Principles of Toxicology. (4) F

Lecture, three hours; seminar, one hour. Prerequisite(s): BCH 110A-BCH 110B or consent of instructor. The structure-activity and dose-response relationships of environmental toxicants; their absorption, distribution, metabolism, and excretion; and evaluation of their toxicity and factors that influence toxicity. Quantitative methods in measuring acute and chronic toxicity. Eastmond.

ENTX 201L.
Laboratory Rotation. (2)

Laboratory, six hours. Prerequisite(s): graduate standing in Environmental Toxicology. Introduction to research techniques in biochemical and chemical toxicology. Students will spend time in a laboratory to familiarize themselves with research topics and techniques. Graded Satisfactory (S) or No Credit (NC). Course is repeatable.

ENTX 202.
Mechanisms of Toxicity. (4) W

Lecture, three hours; seminar, one hour. Prerequisite(s): ENTX 201, BIOL 107 or BCH 110C or consent of instructor. Biochemical and physiological mechanisms underlying the toxicity of environmental toxicants. The interaction of toxicants with subcellular components and macromolecules with emphasis on mechanism of action, in particular neurotoxicity of pesticides, chemical carcinogenesis, mutagenesis, and teratogenicity. Gill, Grosovsky.

ENTX 203.
Toxicology Laboratory. (3)

Lecture, one hour; laboratory, six hours. Prerequisite(s): BCH 102 and ENTX 201 or consent of instructor. Laboratory methods for the determination of toxicity of chemicals and techniques to determine the interaction of toxicants with biochemical and physiological processes. Mehra.

ENTX 211.
Environmental and Molecular Carcinogenesis. (3)

Lecture, three hours. Prerequisite(s): BIOL 107 or equivalent or consent of instructor. Molecular genetics of human cell response to environmental carcinogens. Discussions of DNA repair, mutagenesis, oncogenes, and tumor suppressors. Following presentation of introductory material, emphasis will be placed on student discussion of recent literature. Grosovsky.

ENTX 215.
Toxicants in Aqueous Media. (3)

Lecture, three hours. Prerequisite(s): CHEM 112A-CHEM 112B-CHEM 112C and ENTX 200. Analysis of loss pathways for toxic chemicals present in surface waters, soil or groundwater. Includes chemical and biological degradation and transformation reactions, transport through soil, absorption to solid phases, and volatilization to the atmosphere. Farmer.

ENTX 216.
Biodegradation of Xenobiotic Chemicals. (3) S

Lecture, three hours. Prerequisite(s): BIOL 121A, BIOL 121L, or SLSC 111; BCH 100; or equivalents. The importance of microorganisms in metabolizing synthetic organic chemicals. Ecology, physiology, growth, isolation, and identification of degradative bacteria. Studies of catabolic pathways: metabolites, enzymes, genes, and environmental factors. Bioremediation processes and environmentally related problems. Cross-listed with SLSC 216. Focht.

ENTX 216L.
Laboratory in Biodegradation of Xenobiotic Chemicals. (2) S

Discussion, one hour; laboratory, three hours. Prerequisite(s): BIOL 121A, BIOL 121L, or SLSC 111; BCH 100; or equivalents. Laboratory methods used for isolation and identification of degradative bacteria; kinetics of growth and metabolism; studies of catabolic pathways, separation, and spectroscopic identification of metabolites. Cross-listed with SLSC 216L. Focht.

ENTX 217.
Toxicology of Metals. (4) W

Lecture, three hours; seminar, one hour. Prerequisite(s): ENTX 200 or ENTX 201 or consent of instructor. An examination of the toxicology of essential and nonessential metals. Topics include absorption, distribution, and excretion of metals; chemical and biological monitoring and ecotoxicology of metals; molecular and cellular bases of metal toxicity; metal detoxification and resistance mechanisms; metalloregulation of gene expression; remediation strategies. Mehra.

ENTX 220.
Toxicological Risk Assessment. (4) S

Lecture, three hours; discussion, one hour. Prerequisite(s): ENTX 201 or consent of instructor. An in-depth examination of the principles and methods used to assess risks associated with exposure to chemical and physical agents. Topics include informational resources, regulatory policies, epidemiological and toxicological approaches, interspecies extrapolation, variability in analyses, metabolism and population sensitivity as well as quantitative risk assessment methodologies. Eastmond.

ENTX 244.
Airborne Toxic Chemicals. (3) S

Lecture, three hours. Prerequisite(s): CHEM 109 or CHEM 110A, and CHEM 110B, CHEM 135/ENSC 135/ ENTX 135; or consent of instructor. Atmospheric chemistry of airborne chemicals. Intermedia partitioning. Structure of the atmosphere. Gas-particle distributions of chemicals, and wet and dry deposition of gases and particles. Atmospheric reactions of organic compounds, with emphasis on toxics. Theoretical and experimental methods for the determination of atmospheric lifetimes and products of chemicals. Cross-listed with CHEM 244. Atkinson.

ENTX 245.
Chemistry and Physics of Aerosols. (3) F

Lecture, three hours. Prerequisite(s): CHEM 109, CHEM 110B; or consent of instructor. Fundamentals of chemical and physical processes controlling behavior and properties of airborne particles. Topics include particle mechanics; electrical, optical, and thermodynamic properties; nucleation; surface and aqueous-phase chemistry; gas-particle partitioning; sampling; size and chemical analysis; atmospheric aerosols; and environmental effects. Cross-listed with CHEM 245 and SLSC 245. Ziemann.

ENTX 257.
Graduate Seminar in Cell, Molecular, and Developmental Biology. (1) F,W,S

Prerequisite(s): graduate standing. Lectures by visiting scholars on current research in cell, molecular, and developmental biology. Graded Satisfactory (S) or No Credit (NC). Course is repeatable. Cross-listed with BCH 257, BIOL 257, BMSC 257, BPSC 257, ENTM 257, NEM 257, NRSC 257, and PLPA 257.

ENTX 270.
Seminar in Environmental Toxicology. (1) F,W,S

Seminar, one hour. Prerequisite(s): graduate status in Environmental Toxicology. Lectures by visiting scholars and staff on current research topics in Environmental Toxicology. Graded Satisfactory (S) or No Credit (NC). May be repeated for credit. Mehra.

ENTX 290.
Directed Studies. (1-6)

Research, three to eighteen hours. Prerequisite(s): graduate status in Environmental Toxicology. Literature or research topics under direction of the staff. Graded Satisfactory (S) or No Credit (NC). May be repeated for credit.

ENTX 297.
Directed Research. (1-6)

Research, three to eighteen hours. Prerequisite(s): graduate status in Environmental Toxicology. Directed research performed towards the development of a dissertation problem or other research performed under the direction of staff. Graded Satisfactory (S) or No Credit (NC). May be repeated for credit.

ENTX 299.
Research for Thesis or Dissertation. (1-12)

Research, three to thirty-six hours. Prerequisite(s): graduate status in Environmental Toxicology. Research performed under the direction of a faculty member towards a thesis or dissertation. May be repeated for credit. Graded Satisfactory (S) or No Credit (NC).