Ecotoxicology 551

Major components of aircraft de-icers
ethylene glycol, propylene glycol, additives
Endocrine-disrupting phenolic compounds found in surfactants incorporated into anti-icers.
(alkylphenol polyethoxylate) break down into organic micropollutants
Nonylphenol, octylphenol, and bisphenol A
Major anti-corrosive additives to anti-icers found at an airport in Switzerland
Benzotrialzole and tolytrialoze
Three characteristics of anti-corrosive additive compounds that makes them important freshwater contaminants
High polarity, low biodegradability, high water solubility
Effects of ethylene glycol on dissolved oxygen concentrations
High oxygen demand. Impairs aquatic system
Developmental effects of ethylene glycol diethyl ether in rodents (9)
Reduced maternal weight gain, embryo toxicity, decreased litter size, decreased fetal weight, malformaties, decreased erthocyte counts, decreased hematocrit and hemoglobin, increased blood urea and creatine, histopathologic changes
Kidney as a major target organ of ethylene glycol
Fatty change in liver
How anti-icers can impact microbial components of soils
Toxic to microbes
How runoff from soils can be reduced through land management
Use of plants to remove toxins
Name of herbicide mixture used in Viet Nam war, of which 2,4-D constituted 50%. (The other 50%, made up of 2,4,5-T was contaminated with 2,3,7,8-tetrachlorodibenzodioxin.)
Agent Orange
Toxic mechanism of action in plants.
stimulates uncoordinated growth in some areas while inhibiting others
Type of cancer with which 2,4-D has been linked in dogs and humans beings.
Non-Hodgkin’s Lymphoma in humans and Malignant Lymphoma in canines,
Primary source of exposure to dogs.
. Exposure occurs via contact with the herbicide on household lawns and owner apparel after application of the chemical. Dogs are fastidious groomers and ingest the herbicide by licking their paws and coats
Specimen in which 2,4-D can readily be detected two days after a dog has been exposed.
Urine
Body function in a frog species that was impacted by 2,4-D.
impairs oocyte maturation by blocking meiotic maturation in vitro
Body function in fish that can be impaired by high concentrations of 2,4-D.
Olfaction
Alternatives to herbicides to help reduce weeds.
Mulch
Avian species documented in different outbreaks of AVM.
bald eagles, American coots, mallards, Canada geese, killdeer, buffleheads, ring-necked ducks, great horned owl, American kestrel
How diagnosis of AVM is established & challenge this may represent.
microscopic examination of brain tissue for microscopic vacuolizatino of white matter and lesions
Classical clinical signs of AVM.
Clinical signs are typical of central nervous system damage which includes ataxia, the inability or difficulty to fly, walk or swim. Birds affected by this disease are observed swimming in circles or flying into rock walls
How AVM was reproduced in red-tail hawks.
Fed GI contents of AVM affected coots to hawks
The invasive macrophyte plant on which the toxigenic organism is believed to grow.
Hydrilla verticillata
Epiphytic cyanobacteria that was implicated in AVM.
Stigonematales
Category of herbicide to which atrazine belongs (there are several in this group with similar toxicity).
triazine
Primary crop on which atrazine is applied.
corn
Urban sites where animals may encounter atrazine
pasture, parks, golf courses, christmas tree farms
Mechanism of toxic action of atrazine in plants.
inhibits photosynthesis
States where atrazine is most widely used & trends over the last 15 years in terms of usage.
Illinois, Iowa, Indiana, Ohio, Nebraska, Delaware
Major effect of atrazine in frogs.
hermaphorodite (endrocrine disruptor)
Aspects of environmental fate that increase exposures to atrazine
Water soluble, can evaporate and be redistributed in rain, potential to bioaccumulate, persists in environment for several months
Ecological roles of algae that may be inhibited by atrazine.
Food, oxygen production, shelter
Parts of the world where atrazine has been banned in agriculture.
Europe and Central Asia (Denmark, Germany, Norway, Sweden, Slovenia, Angola, South Africa)
How concentrations of PCBs in orcas whales compare to those in other species.
highest
Why selective retention of PCBs in orcas is a major concern (because the toxicity of the coplanars tends to be greater).
Low activity of detoxifying enzymes
How different populations of orcas develop different feeding habits & thus exposures.
transients- eat other marine mammals and have highest PCB concentrations due to trophic level and bioaccumulation in their prey. Residents eat fish and have high PCB’s
Why it would be risky, but still a better idea for an orca to swim in a pod than a clan or community of orcas.
NOT A LOGICAL QUESTION since several pods made a clan and several clans make a community. What was Val thinking?
How some orcas reflect local sources of PCBs, but others reflect those from far away.
migration? Global PCB transportation? Long Life?
Basis for different adult female & male PCB burdens.
Females pass 60% of PCB load to offspring
Impacts of birth order on body burdens on orcas
First born= highest burden (3-8 times higher than younger siblings)
Late period of life when female orca body burdens increase
after they stop calving (reproductive sensescence)
Body burdens & life expectancy of males compared to females in orcas
Females live longer
Major constraints on population recovery for orcas globally
Historic capture for aquaria, Boat traffic, Food supply pressures, Emergine infections, Global migration, suppressed immune system from PCB’s