Pesticides, POPs, and Metals Flashcards
What makes pesticides unique chemicals?
Pesticides are designed to kill, but we pay to use them and we put them in our environment. We also use it as a public health tool
Health effects related to pesticide exposures include:
Neurological deficits, reproductive toxicants, death (from acute or chronic exposures), endocrine modulating effects
Occupational exposures to pesticides typically occur by what pathways?
dermal absorption and inhalation
Non-occupational exposures to pesticides typically occur by what pathways?
Ingestion with incidental exposures from home use
In the case of Nemagon, describe the environmental justice issues related to the case.
known effects from exposure not shared with workers, poor population, jurisdiction of Nicaraguan courts?, banned from US so moved to developing countries, warnings in English
What is the mode of action of organophosphate pesticides and how do they relate to nerve agents?
They bind to the enzyme that breaks down the neurotransmitter acetylcholine (anti-cholinergic chemicals). They are considered “junior strength” nerve agents because they have the same mode of toxicity but do not bind quite as strongly.
What were PCBs used for and how did they get into our environment?
They were used as dielectric fluids in capacitors. They got into our environment from direct emissions from manufacture or from irreponsible disposal of capacitors or waste.
What two rivers were contaminated with PCBs by GE and what steps have been taken to decontaminate them?
The Hudson (NY) and Housatonic (MA) rivers. EPA has worked with GE on a plan to remove top sediments from the most contaminated areas of the rivers and dispose of them at a waste facility. Over 10 years was used to test and plan the decontamination. The first phase of the Hudson cleanup is completed (~ 6 miles of 200 miles of contaminated riverbeds) and the second phase (~40 miles) has begun. The Housatonic is largely completed. Both should be completed around 2015.
Who are the the most vulnerable for PCB exposure and why? How do we get exposed to PCBs today?
Populations who eat subsistence diets (i.e., polar bears, seals, whale blubber). This often includes vulnerable or underserved populations like inuits. They are most highly exposed b/c of atmospheric redistribution of PCBs to colder climates in the Artic basin. Other areas widely contaminated include the Great Lakes. We are mostly exposed through the consumption of contaminated fish or meat and dairy products.
Of the heavy metals, lead is one of the most studied. What is the approximate half life in blood, soft tissue and bone?
25 days, 28 days, and 27 years
What is one of the most significant impacts of lead exposure?
One of the most significant effects of lead exposure in children is a shift in the population level IQ. Althought his population shift might have a small impact on an individual, it can have a huge impact on the population.
What is the difference between pesticides and insecticides?
insecticides are almost always neurtoxic
How are pesticides related?
EPA and FDA (last large EH policy enacted in 1996) which adds pesticides to account for aggregate and cumulative exposure.
how do botanical pesticides relate to synthetic pesticides in toxicity?
Some such as nicotine that are naturally derivative are more toxic than cholopurophos a synthetic. Typically natural ones are less stable than synthetic which are designed to be more stable.
How does lead behave in the body?
Typically gets in to the bone
