5 - chemical exposure + pesticides Flashcards
what is the significance of the book “silent spring”
this book, written by rachel carson, fostered the modern environmental movement and helped spark the calls for tighter control of pesticides
Carson was inspired by word from her friend about how large amounts of birds had been dying in Cape Cod as a result of the DDT sprayings
three pests which pesticides seek to kill
insecticides - insects
herbicides - weeds
fungicides - fungi
synthetic pesticides
man-made, do not exist in nature
Class 1 pesticide groups
carbamate -
organophosphates - block ACh enzyme - affect CNS
organochlorine
pyrethroid
T/F most synthetic insecticides are organic
true
routes of entry for pesticides
ingested gastric toxins
contact exposure
expectorant
evaporators
systemic effects
effects occurring in tissues distant from site of contact
three classifications of pesticides
class 1 - chemical structure of the pesticide
class 2 - mode of entry
class 3 - action of pesticide and organism it kills
what are the two ways that pesticides enter water
1) flowing (run-down)
2) filtering (leaching)
how do pesticides affect water
pesticides can affect both ground and surface water
LD50 - pesticides
concentration of pesticide which will kill half of the tested organisms in an experiment
Risk = …. (pesticide)
Risk = exposure (amount and/or duration) X toxicity
persistence is determined as …..
half life - half the time necessary for the concentration to be reduced by 50%
T/F the degraded product of a pesticide will always be less toxic
false - degraded pesticides can have byproducts which with less, equivalent, or greater toxicity
direct occupational exposure
the farmers who spray their crops
direct non-occupational exposure
those who live near the agricultural fields sprayed
indirect exposure
those who live far away from agricultural fields exposed to pesticides, but consume the products of these fields or contaminated water
four direct exposure routes
skin
eyes
mouth
respiratory tract
phytoremediation
solar-powered method of removal/reduction of harmful chemicals using plant species
plants absorb the pesticides and converts it to a LESS hazardous toxic compound
microalgae are known as effective biosorbents of
heavy metals and pesticides
they absorb these compounds and produce oxygen
what is myco-remediation
fungi used as pesticide waste management technique for carbon sourced pollutants to convert them to a less toxic compound
bacterial pesticide degradation
pseudomonas, azotobacter, flavobacterium, and arthrobacter are the major bacterial genus which remove pesticides from polluted environments
key aspects of risk outbreak and communication
1) consideration of political, social, and economic factors
2) analyzes risk and risk perception to communicate effectively
3) dialogue with vulnerable peoples and stakeholders
4) ** identify and address rumours, misinformation, and other communication challenges
two facets of risk communication
alerting and reassuring people
risk = hazard (how much harm is it likely to do) + outrage (how upset is it likely to make people)
relation between Hazard and Outrage and the kinds of risk communication
public relations - high hazard, low outrage
stakeholder relations - moderate hazard, moderate outrage
outrage management - low hazard, high outrage
crisis communication - high hazard, high outrage
aspects of effective risk communication
- Timely
- Accurate
- Clear
- Objective
- Consistent
- Complete risk information
