INDEX
TOPIC Atmospheric Pollution DATE ㅁ . ∞ . 4
NOTE
Air pollution s
presence of compounds in the air at levels tnat pose a healtn risk
-
natural processes contribute ,
but numan activity is the main cause
-
tends to be concentrated around areas of α pop density .
-
divided into
primary and
secondary pollutants
Types of Air pollution
primary pollutants
-
s
emitted direstly from source
s ex exnaust , HG No , Co smoke bead
: venicde , , Cor ,
,
and
s ex 2 industry → soz , No 2 , co, coz , tas dust and smoke
, ,
s ex 3 : Fires → Co ,
cOr ,
smoke
s ex 4 :
volcanoes ssox cor rolcanicdust
, ,
secondars pollutants
-
form '
4
in atmosphere when pollutants react with
atmospmeric components
primary
Gex :
Acid rainx sor + No , react witn water , oxygen ,
and otner cnemicals to form sulfuric
and nitric acids cprecipitates containing these acids are called acid rain )
photochemical primary pollutants leg
s ex 2 : s in diret suligbt a mixture of Noand
smog , .
Noz ) and secondary pollutants te g ozone ) react
.
, to form photochemical smog
-
Air pollution occurs botn out and indoors
s can also be either particulates ( some mix of two ( ex : smoke))
gases or are a
Fossil Fuels and Air pollution
-
Fossil fuels
s burned fuel
to produce electricity , power industrial processes ,
and venicles
s coa - fire
powered stations generate 7301 of the worid '
s electricity ( huge comtributor to
air pollution )
when coal is burned combustion ) co 502 Nox toxic metals and particulates
-
, 2 , , , ,
are released
contain sulfur impurities twnen burned - dioxide )
4
many ssulfur is oxidized to sulfur
-
major sources : coal - fired porwer stations ,
volcanic erruptions ,
etc .
can affect air quality
-
-
contribute toacid rain
-
can cause cougning , wheezing , or shortness of breath when breathed in
long term exposure can cause respiratory ill ness
-
, venides are a largecontributor toairpollution
cars produce Co HCs and NO ×
-
, ,
s these
pollutants contribute to poor air quality and are linked to numerous bealtm issues
s new tesh is
helping to reduce tnese harmful emissions
The Clean Air Act ( 1963 )
-
a U s federal
. .
law designed to control air pollution on a national level
-
one of its achievements s
banning the use of lead in gasoline i n on - road venicles
4
Background led tetraetny) lead ( TEl) added to
gasoline to performance
:
or
, ,
was
improve engine
Lais
Iis harmfulto humans evenat l 0o levels
covered to be
accumulating in environment in late 1940 s
-
administered by EPA and has undergone aa number ofadmendments
1973 EPA began reducing level of TE더 gasoline
-
in
s
s
TEl banned in U s . . in 1 aa 6
suse of lead other products has also been bamned lex paints cans and pipes)
:
in
, ,
major sources of lead emission todas oreand mefal processing , emissions from lead -
-
and
containg aviation fuel
COVID 19 -
and Reducing Air pollution
- ockdown s reduced human t lowered tevels of
activity pariculatematfter
harmful because it can be innaled
slong cardiovascular I r risk of
term exposure s
respiratory diseases ,
as well as
lung cancer
, INDEX
Particulate Matter ( PM )
NOTE
pM 2 5 refers to partiales droplets intheair thatare 25 less
-
. or microns or
s
produced by venicles burning wood beating oil or coal and wild fires
, , ,
s also form when certain gases or droplets ce g. . from poner plants ) react in the atmosphere
s is 30 x tninner than human hain
can be inhaled deeplyinto lung tissue and
s
contribute toserious nealtm problems
saccounts for most healtn effects due to air pollutiorn in U s
. .
Photochemical smog
smog
=
type of air pollution
-
-
two types : winter v s
. .
summer smog
s summer
smog is also calledphotochemical smog
-
photochemical smog main effects respiratory system Lcauses / worsens a wide variety of respir
.
atory issues )
s Other health issues : ege and noseirrifation , birthdefects , ete . leffects ofprolonged exposure )
Formation
Largest comtributor s
Nox from venicle emissions
-
-
(
s enter
atmosphere ,
in the presence of sunlignt ,
react witn vo Cs
specifically H Cs ) to form
photochemical smog
7 Vocs are in atmosphere as result of human activity leg - burning fossil fuels) and naturally
occuring processes (e g .
.
from plants)
-
voCs have a ton vapor pressure due to low
boiling point cevap or sublimate @ room temp )
Nox tsunlighf s o
lsingle oxygen atms)
-
☆
( 03 )
combine with molecular oxygen ( o2 ) to
produce ozone
4
ozone in photo chemical smog is called ground level ozone tregarded as a pollutan + )
solar radiation
HO
사
NO 로
NO
^
Atomic
ㅇ Voeculxygent 이
oxygen
VOCs
HNO 3
Nitris
PANs √
acid √ V Aldenydes O
3 ozome
photochemical
smog * nitrates
peroxyacd
s chemicals
present in photochemical smog
:
Nox ,
Voss , oxygen and ozone , HNOs , Aldenydes ,
PANs ( peroxyacyl nitrates )
bam gam → people drive to work :
-
-
solar radiation Nox and rocs increase
?
NO 2 + H 20 ( water ) -
aam - lam - s
sunlignta , Nor absorbs
5
↓ light energy and splits , forrsing No
HNO 3 3 02 + 0 → O3 Lozone ) and O ; Ocombines witn o 2 to form O 3
uu radiation
- am 4
pm
s
sunlight in tensity ↑ :
-
Apositon
co
, NO +
VOC No + ross creleased by vehicles ,
hvenides
PANS refineries , gasstations ) → PANS ;
or ooads No 2 t water vapor , HNO 3
photochemn 4 pm down ;
s sun is
sm going
-
formation of ozone : s
nalted
Effects of ground level ozone
-
s
plant damage ( os enters stomata t oxidizes plant tiss ue
during respiration)
녀 inflame airways
boverall [ )
-
effect on animal + buman respiratory systems
ex airway
obstruction
-
