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Goals
 Determine which chemicals present (or potentially
present) in the Lake Champlain basin would cause
detrimental effects
 Determine the pathways in which these chemicals
come about
Objectives
 Identify potentially hazardous substances
 Establish links between potentially hazardous
substances and the habitats they may impact within
the Lake Champlain basin
 Determine the degree of impact each substance has
upon each habitat type
Subcategories
 Hydrocarbons
 Polycyclic aromatic hydrocarbons (PAHs)
 Volatile organic compounds (VOCs)
 Herbicides
 Atrazine
 Alachlor
 Heavy Metals
 Mercury
 Cadmium
 Lead
Subcategories (cont.)
 Pesticides
 Dioxins & like compounds
 Polychlorinated biphenyls (PCBs)
 Polychlorinated dibenzodioxins (PCDDs)
 Polychlorinated dibenzofurans (PCDFs)
 Pthalates
Polycyclic Aromatic
Compounds
 Form during the incomplete combustion of organic material
 Released in the atmosphere from the burning of fossil fuels,
and are transported to aquatic and terrestrial ecosystems by
way of atmospheric deposition
 Travel via water and sediments, accumulate in soils
 Can bioaccumulate in organisms, leading to higher
concentrations within the organisms than in the surrounding
environment
 Have carcinogenic effects, as well as negative effects on
reproduction, development, behavior, and longevity
Volatile Organic
Compounds
 Typically human-derived/isolated solvents with high
vapor pressure
 Indoor air pollutants which can cause skin irritation
and disorientation when inhaled
 Enter the environment through volatilization or by
dissolving into water, which can have a negative
effect on aquatic ecosystems
 Have been identified as carcinogens with chronic
exposure
Atrazine
 A non-selective herbicide that inhibits photosynthesis in
plants
 Used in commercial agriculture
 Risk to aquatic systems based on toxicity and high
mobility
 Degrades slowly, which allows it to accumulate in animal
tissue
 Impacts gill function, hematology, metabolism, and
behavior in fish species, and sexual determination in frogs
Alachlor
 Selective herbicide which controls unwanted grasses
and broad-leafed weed species in commercial
agriculture
 Can travel through both groundwater and surface
water, moderately through soils
 Chronic exposure increases the likelihood of cancer
in fish and mammals
 Has toxic effects on the liver, spleen, kidneys, and
eyes of rats
Mercury
 Generated from industrial activities, mainly coalburning
 Transported through the environment in the form of
methyl mercury
 Affects mostly marine and wetland habitats, but
moves to terrestrial habitats through
bioaccumulation
Cadmium
 Sources: burning of coal and oil, incineration of
municipal waste, smelting of zinc/lead/copper ores,
phosphate fertilizers, sewage sludge
 Increases the ability of certain plants to resist
infection and disease
 Wide range of health effects
Lead
 Found in most plant and animal tissues, more so than
mercury and cadmium
 Human sources: paints, dishware glazes, moonshine,
gasoline, pipes containing water for a long time
 Causes anemia, neurological damage, chronic renal
disease
 Completely decays Daphnia in 15 days and is toxic to algae
in 30 days
 Lead air pollution in ecosystems causes loss in
biodiversity, change in community composition, and
decrease in growth and reproductive rates in animals
Pesticides
 Organochlorines have been the most harmful and
persistent type of pesticide
 Endosulfan is one of the last organochlorines still
being used today, and transports quickly throughout
the environment due to its volatility, persistence,
and ability to bioaccumulate
 Known to have additive and synergistic effects with
other pesticides, and therefore risk should not be
determined solely upon chemical concentrations
 Amphibians are affected the most by pesticides, esp.
leopard frogs
Dioxins and Like
Compounds
 Released through the incineration of municipal
waste, notably medical waste
 Fat soluble, allowing them to move through habitats
in animal tissue
 Effects of PCBs, PCDDs, and PCDFs can be grouped
as endocrine disruptors, neurotoxins, and
carcinogens
 Dioxins function like hormones, having negative
effects on the reproductive and immune systems,
and can cause tumors
Pthalates
 Absorbed by humans and organisms through skin
exposure, inhalation, and ingestion
 Enter the environment through leaching from
plastics and secretion from urine
 Affect human (male and female) and aquatic
organism reproductive systems
Impact Importance
Stressor
Open Developed
Water
Forest
Herbaceous
Agriculture
Wetlands
Pesticides
1
0.5
0.5
0.5
1
1
Dioxins & the
like
2
1
1
1
1
2
Pthalates
1
0
0
0
0
1
Herbicides
2
1
1
2
2
1
Hydrocarbons
1
2
0
0
1
1
Heavy metals
2
1
1
1
1
2
Impact Link
Stressor
Open Developed
Water
Forest
Herbaceous
Agriculture
Wetlands
Pesticides
1
0.5
0.5
0.5
1
1
Dioxins & the
like
1
1
1
1
1
1
Pthalates
1
0
0
0
0
1
Herbicides
1
0.5
0.5
1
1
1
Hydrocarbons
1
1
0
0
0.5
0.5
Heavy metals
1
1
1
1
1
1
Impact Filter
Stressor
Open Developed
Water
Forest
Herbaceous
Agriculture
Wetlands
Pesticides
1
0.25
0.25
0.25
1
1
Dioxins & the
like
2
1
1
1
1
2
Pthalates
1
0
0
0
0
1
Herbicides
2
0.5
0.5
2
2
1
Hydrocarbons
1
2
0
0
0.5
0.5
Heavy metals
2
1
1
1
1
2