Lec4 Flashcards
First larger-scale aquatic environmental issue resulted due to what?
lead water pipes that were used in large Roman towns.
eutrophicaion caused by fertilizing compounds from:
- human settlements
- industry
- agriculture
- aquaculture
Why gut bacteria are still a major component to be determined when water quality criteria are established?
Because it’s can cause epidemics of intestinal
diseases like Cholera sp.
effected on streams and lakes in Norway, Sweden, and Finland, where whole fish stocks, especially of salmonids, were wiped out.
acid rain
contamination of water is of the greatest effect on:
➢ fish stocks
➢ fish diversity
Only biotic factors may cause the transformation
T/F?
F,Both abiotic and biotic factors.
are needed in small amounts in enzymes, oxygen-carrying pigments, etc., but become toxic in high concentrations.
Essential metals
are not needed, and they are toxic immediately after a limiting concentration has been reached.
Nonessential metals
- used in water pipes
- part of the active group of several enzymes and the invertebrate oxygenbinding protein hemocyanin.
- metal is needed in small amounts.
Copper
- was a component of leaded fuel
- organometallic compound
Lead
Major aquatic pollution sources:
➢ effluents of paint manufacturing.
➢ Industries
➢ households using lead-containing paints or batteries
➢ addition to mining effluents.
➢ Lead as weights for fishing nets
- toxicologically important metal with no known biological need.
- In nature it is always associated with zinc.
Cadmium
- fourth most abundant on the Earth’s surface
- major component of hemoglobin
Iron
Iron toxicity occurs when the body has too much iron.
T/F?
T
- associated with environmental acidification.
- common elements of the earth’s crust.
Aluminum
- ion is one of the most toxic forms of a heavy metal.
- use in water purification, wound care, orthopedic surgery, and cardiac devices
- antibiotic in human health care.
Silver
- has been used as a poison.
- pesticides and components of semiconductors.
- first chemical warfare agents, and the stockpiles of these have subsequently been dumped to the bottom of the sea.
Arsenic
- used in thermometers.
- used in extracting gold.
Mercury
Elemental mercury was used in:
o thermometers.
o still used in batteries.
o light tubes.
o used in extracting gold.
containing carbon–carbon bonds.
Organic compounds
■ Organic compounds include:
o alkanes and alkenes.
o phenols.
o compounds with imidazole.
o benzene rings.
lipophilicity of organic compounds is low
T/F?
F, high
