LITHUANIAN UNIVERSITY OF AGRICULTURE FACULTY OF AGRONOMY. Department of Botany STUDY SUBJECT DESCRIPTION FOOD TOXICOLOGY

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1 LITHUANIAN UNIVERSITY OF AGRICULTURE FACULTY OF AGRONOMY Department of Botany STUDY SUBJECT DESCRIPTION FOOD TOXICOLOGY Study level: BSc Number of ECTS credit points: 4,5 Teaching method: Lectures, supported by PowerPoint presentation and slides, laboratory. Prerequisities: Basic knowledge of biology, ecology, genetics, chemistry. Teaching aids: Scripts referring to the actual topics are distributed during lectures. Examination method: Written examination, by appointment Registration for course: Two weeks before the beginning of the course. Registration for examination: With lecturer, personally or by phone. Remarks: The lecture deals with the importance of food toxicology, for biological research, biotechnology and various life cycles on earth, presents the fundamentals and some frontiers in food microbiology, principles which influence toxicants springing, remaining and removing from foods. Subjects are environmental and natural toxicants foodborne pathogenic bacteria, mycotoxigenic molds. The course begins with a historical perspective and events which led to the field of toxicology. General principles of toxicology are covered such as dose response, types of toxic responses, factors affecting toxicity of chemicals, and toxicity testing guidelines and procedures. Other general lectures include basics of genetic toxicology, carcinogenesis, teratology, bio-transformation of chemicals and risk assessment. Other topics covered in depth directly related to food include food allergy, food irradiation, food additives, food biotechnology and regulation of food safety. The course concludes with lectures on the toxicology of specific classes of chemicals found in food such as pesticides, natural toxicants and antitoxicants and natural toxins from plant, animal fungal and bacterial sources. The course is offered for 3 credits in lecture format. Graduate students are required to write a term paper and make short presentations in class on current topics in toxicology. Students taking this course should be able critique and evaluate toxicology of agricultural products studies; recognize significant issues related to chemical food safety problems; evaluate hazards related to chemicals in food; recognize sources of chemical contamination in food; be knowledgeable of current topics in food toxicology.

2 2 INTRODUCTION Food toxicology is concerned with assessing the injurious effects on living systems of chemicals present in foods and feeds. The chemical agents can be man-made (e.g., pesticide residues, food additives, contaminants originating with processing machinery, or packaging materials) or of natural origin (e.g., microbial, animal or plant toxins). They can, of course, also have been generated in the course of preparing, processing, and preserving foods (e.g., mutagens and carcinogens); in fact, in some instances, the chemicals can be the pure foodstuffs themselves. It is important that students of food science as well as environmental toxicology are familiar with the basic chemical and biological aspects of the injurious substances present in foods and feeds. This course wishes to develop an understanding of the chemical and biological principles that determine toxicity and, by presenting typical examples of the toxic substances found in foods, it lets students become familiar with their properties, modes of action, and methods of analysis. The main objective of the course is to provide students with a basic understanding of the principles of toxicology of agricultural produtcs with an in depth understanding of how this science is applied to chemical food safety. Course Objectives Provide students with a basic understanding of the principles of toxicology. Provide students an in depth understanding of how the science of toxicology is applied to chemical food and feed safety, including food regulation and risk assessment. demonstrate skills for the identification and control of microbial and other food contaminants. Syllabus Theory (32 hours): Introduction to food toxicology. Natural Toxicants Present in Foods (animal, plant toxins). Natural Toxicants Brought into the Food Through Spoilage (microbial toxins). Environmental factors influencing growth of toxigenic microorganisms. Toxicants formed in Processed Foods (food mutagens, carcinogens). Biotechnology in agriculture. Environmental Toxicants (heavy metals, pesticides, industrial contaminants). Food and feed additives and their toxicological evaluation. Control of agricultural products. Practice classes (16 hours) 1. Preparing of microbiological preparations. Fixing and simple staining of microbes (20 %) 2. Differential methods of staining Gram stain. Gram-positive (Gm+) and Gramnegative (Gm - ) microorganisms (20 %) 3. Identification of toxigenic fungi. Morfological properties of field and storage fungi (20 %) 4. Methods of enumeration of microorganisms in agricultural products (20 %) 5. Control of microbial agents of food spoilage, methods of sterilization (20 %) Independent work (32 hours)

3 3 1. Preparation for labs 12 hours 2. Examination 20 hours LITERATURE MAIN LIST 1. Schlegel H., 1988: General Microbiology. - Cambridge, New York, New Rochelle, Melbourne, Sydney.: Cambridge University Press. 2. Chelkowski J. (ed.), 1991: Cereal grain. Mycotoxins, Fungi and Qality in Drying and Storage. Elsevier, Amsterdam. 3. Booth C. (ed.), 1981: Methods in Microbiology. London New York. 4. Gerlach W., Nirenberg H., 1982: The Genus Fusarium a Pictorial Atlas. Berlin. 5. Samson R., van Reenen-Hoekstra E., 1988: Introduction to food-borne fungi. Netherlands. ADDITIONAL LIST 1. Cole R., Cox R., 1981: Handbook of Toxic Fungal Metabolites. Academic Press, New York 2. Garalevičienė D., 2001: Mycotoxins and Moulded Feed Effects on Laying Hen and Contamination of Lithuanian Feeds. Doctoral thesis, Swedish University of Agricultural Sciences, Uppsala 3. Marasas W. F. O., Nelson P. E., Tousson T. A., 1984: Toxigenic Fusarium species: Identity and Mycotoxicology. University Park, PA, Pennsylvania State University Press Study programme prepared by Lecturer, dr. Aurimas Krasauskas Department of Botany, Faculty of Agronomy, Lithuanian University of Agriculture Universiteto 10, Akademija, LT Kauno raj., Lithuania Phone: Fax.: aurimas.krasauskas@lzuu.lt Signature:

4 4 ANNEX CONTENT OF STUDY PROGRAMME LESSONS (32 hours) 1. Introduction to food toxicology (12 %) Scope, history and development of toxicology. Principles of food toxicology. Classifications and divisions in Toxicology. Classes of toxicants. Indicators of toxicity and their evaluation. Understanding about Safe Food and Nutrition. Further developments of Toxicology. 2. Natural Toxicants Present in Foods (animal, plant toxins) (15 %) Natural toxicants present in foods (plants, animal, marine and microbial toxins). Phytoalexins, alcaloids, inhibitors of enzymes and toxic proteins, cyanogenic glycosides, phenols. Antagonists of vitamins. Xenobiotics. Natural carcinogens in animal and plant materials. Types of these dangerous chemical substances and their effects on living organisms. 3. Natural Toxicants Brought into the Food Through Spoilage (microbial toxins) (25 %) Food-borne disease agents among the major microbial groups: fungi, bacteria, algae viruses, protozoa and worms. Methods of identification and characterization of microbes. Bacteria staining techniques - simple, differential-staining techniques of microorganisms, spores and food poisoning microorganisms; microbial growth and survival; food toxicants; Bacteriotoxins (botulin and other bacterial exotoxins). Mycotoxins (aflatoxins, trichothecenes, ochratoxins, and fumonisins); their production, properties and regulation; microbial genetics. Control of microbial agents of food spoilage: methods of sterilization, physical and chemical agents, radiation & filtration, indicator microorganism's for sterilization methods. Parameters affecting microbial growth in food. 4. Environmental factors influencing growth of toxigenic microorganisms (12 %) Cultivation and research of toxigenic microorganisms. Microbiological media, enriched medium, enrichment medium, transport medium, selective medium & pure culture techniques. Methods of preservation and maintenance of cultures. capsules. Morphological, nutritional, metabolic, cultural, antigenic and genetic characteristics). Environmental factors influencing the growth arid survival of in microorganisms. Physical factors - temperature, light, osmotic pressure and hydrostatic pressure. Chemical factors - ph, 0 2 and CO 2. Biological factors - inter-reactions of microbial population and community dynamics - growth in closed environments and in open environments, The kinetic principles of competition between microbial populations. 5. Toxicants formed in Processed Foods (food mutagens, carcinogens) (6 %)

5 5 Food Engineering Basic Terms and Principles. Toxicants formed in processed foods. Hazardous chemical compounds arising from processing and storing of foods. Heating and Chemical Changes. Changes to Frying Food and Frying Oil. Conservation. Radiation and Microwave Energy. Nitrosamines and other biologically active nitro compounds. Polycyclic aromatic hydrocarbons. 6. Biotechnology in agriculture (10 %) Genetically modified foods. Current trends in the production of genetically modified foods; Transformation methods for plants and animals; improvement of food products and increasing food production through gene transfer; finding genes of interest for enhancing food quality. Ethical issues concerning GM foods; testing for GMOs; current guidelines for the production, release and movement of GMOs; labeling and traceability; trade related aspects; biosafety; risk assessment and risk management. 7. Environmental Toxicants (heavy metals, pesticides, industrial contaminants) (8 %) Dose-effect relationship. Factors affecting toxicology. Toxicity testing. Health Effects of Nitrate, Nitrite and N-Nitroso Compounds. Pesticides. Heavy metals and other toxic elements (lead, arsenic, mercury, cadmium and others). Radionuclides. Organic environmental contaminants of industry (polycyclic aromatic hydrocarbons, diphenyls, dioxins and pentachlorophenol) 8. Food and feed additives and their toxicological evaluation (6%) Subcategories of foods additives (acidifiers, color fixers, food colorings, preservatives, sequestrants and sweeteners. Enzymes as additives in foods and feeds. Allergens. 10. Control of agricultural products (6%) Food and feed laws and standards in Lithuania and other countries. Concepts of food quality and safety.