C3 - Pesticides Flashcards
Define Pesticide
Any chemical used to directly control pest polulation or to prevent or reduce pest damage
Define Biocide
A pesticide targeted at microbial pests
List some disadvantages of biocides
Can adversely affect people, nontarget organisms and the environment if not applied correctly
What are the four methods of pesticide classification?
1 - Types of pests managed
2 - How they work
3 - Chemistry
4 - Formulation
What is a biocide that has the ability to killl or inhibit more than one type of organism?
Broad Spectrum (can kill bacteria AND algae)
What are the mode of action of biocides? (how they work)
Contact - kill by contact Broad Spectrum - kill two or more types Sterilants - unable to reproduce Systemics - absorbed into organism and distributed Fumigant - kill by toxic vapor
What are the two biocide chemistry types?
Oxidizing and Non-Oxidizing
Chlorine and Bromine (HOCl and HOBr) are types of what kind of biocide?
Oxidizing - burn the biological matter (oxidize)
Give examples of Non-Oxidizing biocides
Quats, aldehyde, organosulfurs, organics
What are some considerations for QACs?
Not as strong in hard water, or when a lot of organic and solid matter are present.
Most are great for managing bacteria and algae, and more are broad spectrum
What is the most common biocide formulation
Liquid - can be pumped, controlled via DCS for automatic feed
What is an adjuvant
An additive to increase effectiveness
What is Cross Resistance?
When a microorganism develops resistance to two or more compounds that are usually chemically-related with a similar mode of action
What is Multiple Resistance? How is it caused and how can it be overcome?
Microorganism can tolerate biocides from different classes of compounds with unlike modes of action.
Caused when the last 1% which isn’t killed reproduces over and over again to create a new resilient breed
Fought by using new or altered biocides and changing the use patterns.