Midterm 2 Flashcards
what are the 3 types of aquatic toxicity tests
Static
static renewal
flow through
What is a static toxicity test
a static toxicity test has the exposure solutions prepared at the beginning of the study and these are the exposures which remains for the duration of the test
what is a static renewal toxicity test
one in which exposure solutions are replaced at regular intervals over the course of the test
what is a flow through exposure
the effluent is continuously supplied to the test vessel during the course of the study
static vs flow through
flow through is much more complex and challanging to maintain and requires regular monitoring, used for chemicals which are volatile or for chemicals which degrade quickly
LOEC
lowest observed effect conc
NOEC
no observed effect conc, the highest tested concentration which does not cause any observed or statictcally adverse effects
TEC
threshold effect conc, mean of loec and noec
what is the relatioship between LOEC and NOEC and the exposure conc
they are dependent on the exposure contrations meaning that they can change based on the interval at which you observed effect
What is hormesis
hormesis is an observed positive response compared to the control organism at low conc in a tox test
what can reduce the toxicity of metals in fresh water
DOC as it forms complexs with the metal ions which once bound are no longer toxic
in what from is metal the most toxic when dissolved
ion
what are 2 factors which can reduce toxivity of metals in water
DOC and Water hardness
how do metal ions induce there toxicity on fish
via the gills since they regulation the internal ionic balance and move ions in and out of the body via active transport if however metal ions are present then they take up this space and reduce the amm of esstinal ions which can enter the cell
what are the 2 deferent sources from which DOM can originate
Allochtonous- arises from sorounding catchment
Autochtonous- arises from the aquatic system
what are the three Cs associated with the biotic ligand model
Concertation
Complexation
competition
what are some envoirmental impacts of mining
Dust, noise
erosion
metal contamination
relase of chemivals
acid and acid rock drainage
what are tailings
group rock and process effulents which are generated in a mine processing plant(waste from ore extraction)
where to tailings go
TMF tailing managment facility
TSF- tailings storage facility
what is a orphanded or abandoned mine
-Owner cannot be found or owner is unable to unwilling to carry out clean up
what are some abandoned mines in canada
giant mine
kam kotia
britannina
who is Robert Fireland
he was neamed devleoper of the yeat in 1996 while leaving mines abandoned and the envoirment heaviliy polluted
what is the fastest growing soild waste stream
E-waste
what is bioaccumulation
the progressive increase in the amount of a substance in a organsim or party of an organism that occurs bc the rate of intake exceeds the organisums ability to remove the substance from the body
