Pesticide Use, Mode of Action and Ecotoxicology

Course content

The rationale behind the development of pesticides, their use 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. 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 populations and communities. Risk assessment of the pesticide use is evaluated in relation to ecotoxicology, and the national and international registration systems. An excursion to FMC-European Innovation Center, the section of Research and Development of the only Danish pesticide producing company ( and a visit on a demo-farm is an integral part of the course.


MSc Programme in Agriculture
MSc Programme in Environmental Science

Learning outcome

The students should know about the scientific principles of how chemical, physical and biological properties of pesticides affect uptake, distribution, metabolisation and excretion of the pesticides, and how the mode of action of the pesticide determines their effect on different organisms. They should know about pesticide use in agriculture, horticulture, forestry, public land and households and about their ecotoxicological side effects. And they should know how knowledge on adverse effects on humans and the environment is used in the risk assessment and legislation of pesticides in Europe. 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.

  1. Knowledge:
  2. - Know how chemical and physical properties of pesticides affect uptake, distribution, metabolisation and excretion of pesticides in plants and animals
  3. - Know the site and mode of action of exemplary pesticides representing the most used pesticide groups
  4. - 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
  5. - Know how pesticide effects on humans and the environment is assessed
  6. - Know the rationale behind pesticide development and registration
  9. Skills
  10. -Set up experiments to test for the effect of herbicides, fungicides and insecticides on target or non-target organisms
  11. - Statistical analysis and biological interpretation of dose-response data from bioassays with various organisms and endpoints (binary and gradual endpoints)
  12. - Analyse and interpret data from mixtures toxicity experiments
  13. - Assess efficacy/toxicity of herbicides and recognise characteristic symptoms of exemplary modes of action
  14. - Evaluate toxicity data in a regulatory context
  15. - Apply quantitative methods to assess pesticide load, drift and fate in organisms and environment
  17. Competences
  18. - Evaluate pesticide applications to target and non-target organisms in the terrestrial and aquatic environments
  19. - Put various theories and principles of pesticide action into perspective and make sound judgment of impact of pesticides on different environments
  20. - Discuss pesticide use from a scientific stand in view of its controversial issue in the public

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 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 last part of the course, giving the students and opportunity to discuss pesticide use, use-principles in the EU and practical testing of pesticide efficacy and safety with the industry.

The exact editions will be written on Absalon.

Examples of course literature:

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


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

Basic knowledge in chemistry, biology, plant physiology and statistics

Academic qualifications equivalent to a BSc degree is recommended.

Continuous feedback during the course of the semester
Feedback by final exam (In addition to the grade)
Peer feedback (Students give each other feedback)

Written and oral feedback is given for all reports on a report-group basis. All reports thereafter have to be re-submitted. Peer-feedback is given on the final presentation, with different groups being asigned to give feedback on the individual presentations. All students are encurraged to ask questions to practical and theoretical exersises during the course and can be expected to recieve feedback on their questions and enquiries.

7,5 ECTS
Type of assessment
Oral examination, 20 min
Oral examination in reports and curriculum, 20 min. preparation
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
  • Class Instruction
  • 5
  • Preparation
  • 100
  • Theory exercises
  • 20
  • Practical exercises
  • 40
  • Excursions
  • 10
  • Project work
  • 10
  • Exam
  • 1
  • English
  • 206


Course number
7,5 ECTS
Programme level
Full Degree Master

1 block

Block 3
Study Board of Natural Resources, Environment and Animal Science
Contracting department
  • Department of Plant and Environmental Sciences
Contracting faculty
  • Faculty of Science
Course Coordinator
  • Nina Cedergreen   (3-70656842726e6770306d7730666d)

Helle Marcussen - Pesticide fate

Saved on the 16-03-2022

Are you BA- or KA-student?

Are you bachelor- or kandidat-student, then find the course in the course catalog for students:

Courseinformation of students