Monitoring for pesticides (Week 9) Flashcards
What are POPs
Persistant Organic Pollutants are chemical substances that are toxic, persist in the environment for long periods of time, bioaccumulate through the food chain and pose a risk to human health and the environment.
What are some anthropogenic sources of toxic pollutants
Industrial effluent
Oil spills
Pesticide in agriculture runoff
Sewage waste
Hazardous waste
Combustion
What does EU legislation require for medicines before they are licensed for production
Must be subject to an environmental risk assessment.
Only compulsory for new medicines since 30th October 2005
What does PEC stand for
Predicted Exposure Concentration
What does PNEC stand for
Predicted no effect concentration.
intended to be conservative and predict concentration a chemical will likely have no toxic effect
What are the problems in risk assessment for pharmaceuticals
Aquatic organisms are exposed to low levels of pharmaceuticals over long periods of time.
When does an additive drug reaction occur
When the combined effect of two drugs is equal to the sum of each drug given alone
When does a synergism drug reaction occur
When drugs interact with each other and produce an affect that is greater than the sum of their separate actions
When does an antagonistic drug reaction occur
When one drug interferes with the action of another causing neutralization or a decrease in the effect of the other drug
What problems has indiscriminate use of pesticides caused
Affect non-target species
Target pests may develop resistance
Persistent in environment
Food chain magnification
What is DDT
Dichloro - diphenyl - trichloroethane.
DDT belongs to chemical group called organochlorines or chlorinated hydrocarbons.
What does DDT do to human health.
Was used as pesticide.
Interferes with nerve cells.
Can kill animals, not species specific.
Due to persistance in environment single applicatin can kill insects for months
Why is DDT and other organochlorides so damaging to the environment
Soluble in fat oils and lipids ; Lipophilic
Accumulate in animals fat cells ; Bioaccumulation
Passed through the food chain ; Biomagnification
How did DDT affect top bird predators
Disrupts calcium metabolism resulting in thinner bird eggs.
Resulted in decline in bald eagle, Californian condor
What are organophosphates
Common ingredient in sheep dip
Extremely toxic to animals/humans
Link to adverse effects in neurobehavioral development of fetuses/children
