Pramita Flashcards
Classification based on mode of release
Indoor:
Indoor air quality refers to the air that occupies
confined, non-industrial environments.
Eg:- Dust, mold, fungi spores, cooking gasses,
and cigarette smoke, cleaning and personal
care products, laundry detergents
Outdoor:
Emissions caused by combustion
processes from motor vehicles, solid fuel
burning and industry.
based on degradability
Biodegradable :woods, domestic sewage papers etc
No biodegradable:Mercury compounds of Phenol,
Glass, DDT, Benzene, Pesticides
Health Impact of oullutats
Respiratory and Cardiovascular diseases
Economic Impact
Healthcare costs
Loss of Biodiversity and
Ecosystem services
Damage to property and
infrastructure
Tourism decline
Impact on Labor markets
Environmental Impact of Pollution
Global warming and climate change
● Ozone layer depletion
● Acid rain
● Eutrophication
● Destruction of marine ecosystem
● Deforestation and habitat loss
● Impact on Biodiversity
Water pollution
degrading water quality
and rendering it toxic to
humans or the
environment.
Unsafe water kills more
people each year than war
and all other forms of
violence combined.
Point Sources
● Industrial Discharges
● Sewage and Wastewater Treatment
Plants
● Oil Spills
● Mining Activities
Non-Point Sources
● Agricultural Runoff
● Urban Runoff
● Stormwater Runoff
● Sediment Runoff
Agriculture is the one of the
source of contamination
One of the major
contributor to
contamination to estuaries
and groundwater.
define water quality?
Water quality is a measure of the condition of water relative to the
requirements of one or more biotic species and/or to any human need or
purpose.
Potable water:
It is safe to drink, pleasant to taste and usable for domestic
purposes.
Palatable water:
It is esthetically pleasing; it considers the presence of
chemicals that do not cause a threat to human health.
Contaminated water:
water containing unwanted physical,
chemical, biological, or radiological substances, and it is unfit for drinking
or domestic use
Infected water:
contaminated with pathogenic organism
Parameters of water quality:Physical
4TEC
● Turbidity
● Temperature
● Taste and odor
● Total dissolved solid
● Electrical conductivity (EC)
● Color
Parameters of water quality:Chemical
● Dissolved Oxygen (DO)
● Biochemical Oxygen Demand (BOD)
● Chemical oxygen demand (COD)
● Salinity
● pH
● Alkalinity
● Nutrients (Nitrate, Nitrite, Ammonia, Phosphate)
● Chloride
● Heavy Metals (Lead, Mercury, Cadmium, Arsenic)
● Pesticides and Herbicides
pH water
PH= - log [H+] = - log [H3O+]
POH= - log [OH-]
Normal rainfall
pH of approximately 5.6 (slightly
acidic) owing to atmospheric carbon
dioxide gas.
Safe ranges of pH for drinking water
6.5 to 8.5 for domestic use
BOD
is not an accurate quantitative test, although it is considered as an indication of
the quality of a water source. It is most commonly expressed in milligrams of
oxygen consumed per litre of sample during 5 days of incubation at 20 °C or 3 days
of incubation at 27 °C.
Measure of BOD =
Initial oxygen- Final Oxygen after (5 days at 20 °C) or (3
days at 27 °C)
BOD
BOD is the amount of oxygen (Dissolved Oxygen (DO)) required for the biological
decomposition of organic matter. The oxygen consumed is related to the amount of
biodegradable organics.
P is called as dilution factor
it is the ratio of sample volume (volume of wastewater) to total volume (wastewater plus dilution water).
biological oxygen demand
the saturated value of DO for water at 20o C is 9.1 mg/L only
the oxygen demand for wastewater may be of the order of several hundred mg/L,
therefore, wastewater are generally diluted so that the final DO in BOD test is always ≥ 2 mg/L.
BOD= (DOi -DOf)/P
Modeling BOD as first order reaction
BOD=L(1-e^-kt)
Where k20 is the value of k at 20 o C and is an empirical constant.
theta= 1.135 T => is between 4 - 20 oC;
theta= 1.056 T => is between 20 - 30 o C
test of sewage content
a. Organic matter which can be biologically oxidized is called biologically active
b. Organic matter which cannot be oxidized biologically is called biologically inactive.
COD
oxygen required for the complete oxidation of both biodegradable and
non-biodegradable matter.
● COD is a measure of the oxygen equivalent of the organic matter content of a sample that
is susceptible to oxidation by a strong chemical oxidant.
COD
milligrams per liter (mg/L), which indicates the mass of oxygen
consumed per liter of solution.
Parameters of water quality:Biological
● Bacteria
● Virus
● Parasites
● Algae
Aquatic Pollution: different from water pollution
Encompasses not only the pollution of the water itself but also the impact on the
entire aquatic ecosystem. This includes the water, the organisms living in it (fish,
plants, microorganisms), and the surrounding environment.
Water pollution primarily focuses on the quality of the water itself,
Eutrophication
which occurs when the
environment becomes enriched
with nutrients, increasing the
amount of plant and algae
growth to estuaries and coastal
waters.