Pesticide Use, Mode of Action and Ecotoxicology

Course content

The rationale behind the development of pesticides, their use, physical and chemical properties and their regulation is the frame of references of the course. The importance of mode of action and site(s) of action of pesticides will be stressed and linked to chemical properties, uptake, translocation and metabolism in target and non-target organisms. The principles of assessing pesticide selectivity will be an integral part of the course as is the research and development of pesticides in Industry and public institutions. We deal with formulations of pesticides and use of adjuvants to enhance efficacy, either by the manufacture or by the end user. Various reference models to assess joint action of pesticide mixtures are taught and the implication to their use is validated and side effects are described. We focus on aquatic and terrestrial ecotoxicology in relation to pesticide loads, intentional and not intentional discharge in the environment and also the ecotoxicological effects of pesticides on population and communities. Risk assessment of the pesticide use is evaluated in relation to ecotoxicology, and the national and international registration systems. An excursion to Cheminova (http://www.cheminova.dk), the only Danish pesticide producing factory and the private field and laboratory testing company Agrolab (http://www.agrolab.dk/) is an integral part of the course

Education

MSc Programme in Agriculture
MSc Programme in Environmental Science

Learning outcome

The students should know about the scientific principles of chemical, physical and biological properties of pesticides, their use in agriculture, horticulture, forestry and public land and their ecotoxicological side effects. The curriculum encompasses the advantages and disadvantages of pesticide use, the knowledge of which is instrumental for those who wish to work with pesticide development, their management and use in industry, agriculture, horticulture, forestry and on public domains, their legislation and registration.

Knowledge:
- Describe chemical and physical properties of pesticides and know the site and mode of action of exemplary pesticides representing the most used pesticide groups

- Know the principles of pesticide use in crops and for non-agricultural purposes (pest and vector control) including their effects on both target and non-target organisms
- Summarise the rationale behind pesticide development and registration
- Classify pesticides and reflect about their impact in relation to use, load and ecotoxicology

Skills
- Statistical analysis and biological interpretation of dose-response data from bioassay with various organisms and endpoints

- Analyse and interpret data from mixtures toxicity experiments
- Assess efficacy/toxicity of herbicides and recognise characteristic symptoms in the field and greenhouse.
- Evaluate toxicity data en a regulatory context
- Apply quantitative methods to assess pesticide load, drift and fate in organisms and environment.

Competences
- Evaluate pesticide applications to target and non-target organisms in the terrestrial and aquatic environments
- Put various theories and principles of pesticide action into perspective and make sound judgment of impact of pesticides on different environments
- Discuss pesticide use from a scientific stand in view of its controversial issue in the public
- Put into perspective the effect of manipulating agro-ecosystems on sustainability in relation to food production

Lectures will outline the theoretical background for pesticide chemistry and physical properties, their use and effect on target and non-target organisms and the environment. These lectures are supported by practical and theoretical exercises. The practical exercises are in the field, greenhouse and in growth chambers and will address the topics: herbicide application and symptom development over time, assessment of efficacy, species selectivity, systemicity, effect of exposure duration, use of non-lethal endpoints, pesticide uptake, mode of action, recovery and mixture toxicity. The test organisms are terrestrial and aquatic plants, crustaceans, earthworms and pathogenic fungi. Standard OECD and ISO guidelines and other setups will be used. The theoretical exercises will deal with proper statistical analysis of data from the practical exercises by the use of dose-response curves, calculations of spray applications and pesticide load, simple models to assess fate of pesticides in the environment, calculations of uptake and translocation of pesticides in plants, calculations and discussions of environmental impact of pesticides, risk assessment and legislation needs. The excursion will take place in the first part of the course, giving an introduction to practical pesticide use, use-principles in the EU and practical testing of pesticide efficacy and safety.

The exact editions will be written on Absalon.

Stephenson G.R. and Solomon K.R, Pesticides and the Environment, CNTC Canadian Network of Toxicology Centres.

Handouts

Cedergreen, N. 2017, Manual for laboratory and theoretical exercices

Basic knowledge in chemistry, biology, plant physiology and statistics

ECTS
7,5 ECTS
Type of assessment
Oral examination, 20 min
Oral examination in reports and curriculum, 20 min. preparation
Aid
All aids allowed
Marking scale
7-point grading scale
Censorship form
No external censorship
One internal censor
Criteria for exam assessment

See description of learning outcome

Single subject courses (day)

  • Category
  • Hours
  • Lectures
  • 20
  • Theory exercises
  • 20
  • Practical exercises
  • 40
  • Excursions
  • 10
  • Preparation
  • 100
  • Colloquia
  • 5
  • Project work
  • 10
  • Exam
  • 1
  • English
  • 206