study guide ch 3 Flashcards
point pollution sources
wastewater discharge , industrial discharge, mine drainage
non point pollutant sources
agricultural runoff, erosion, atmospheric deposition
waterborne infection and example
acquired by ingesting(drinking) pathogens
ex: giardia lamblia- causes diarrhea, best removed by filtration
oxygen demanding pollutants
the biodegration of organic waste from sewage and industrial effluents creates an oxygen demand
methemoglobinemia
-NO3 reduced to NO2 in saliva and GI tract
-conversion occurs more readily in the higher pH of infant GI tract
-causes hemoglobin to oxidize to methemoglobin which cannot carry oxygen
-known as cyanosis or blue baby syndrome
nitrogen cycle
-movement of nitrogen throughout the atmosphere, hydrosphere, biosphere, geosphere
organic: plants and algae, food, fish
inorganic: nitrate, bacteria, urine waste(ammonia)
-high levels of ammonia in water indicate recent pollution
-nitrites and nitrates indicate historical pollution
Heavy metals pollutants
groups of metals with high density
lead, cadmium, chromium, iron
effects on the nervous system and kidneys
pesticide classification
classified by how long they remin in the environment:
Nonpersistent- days to 12 weeks
moderately persistant- 1 to 18 months
persistant- 1 to 20 years
permanent- most heavy metals-mercury,lead,arsenic
how are trihalomethane are formed
when chlorine or some other member of the halogen family react with organic substances(plant matter)
relationship between radium and radon
radium decay produces radon-more chemically stable
radon
odorless, colorless gas
lung hazard due to daughter product
2nd leading of lung cancer
groundwater pollution
1-2% of groundwater is polluted
25% of drinking wells are polluted
sources of groundwater pollution
gas tanks/underground storage tanks
waste dumps
why groundwater contamination is hard to clean up
CHEMICAL:
-toxicity
-restraint to degradation
-mobility
TREATMENT DOMAIN:
-difficult to find and remediate
