WHAT
IS
AIR
POLLUTION
?
Air
pollution
is
the
effect
caused
by
____________________
of
solids
,
liquids
or
gases
in
the
air
that
have
a
negative
impact
on
the
surrounding
environment
and
people
.
There
are
many
pollutants
and
they
may
occur
____________________
(
from
dust
,
wildfires
and
volcanoes
)
or
from
human
activity
,
be
____________________
or
____________________
,
emit
an
odor
or
be
____________________
.
Various
air
pollutants
can
stay
in
the
atmosphere
from
minutes
to
years
and
,
while
often
considered
a
local
issue
,
may
have
a
range
that
is
local
,
national
,
regional
or
global
.
Air
____________________
is
often
understood
as
an
urban
issue
and
it
is
true
that
cities
concentrate
economic
____________________
and
demand
for
energy
services
,
and
,
so
,
tend
to
experience
the
most
____________________
concentrations
of
air
pollution
.
The
precise
mix
of
pollutants
and
the
____________________
of
the
health
impacts
are
different
from
Paris
to
Delhi
,
Los
Angeles
to
Lagos
,
Beijing
to
Mexico
City
,
but
all
have
air
____________________
that
reduces
life
expectancy
.
Air
pollution
does
not
stop
at
the
city
gate
:
the
sources
are
widespread
,
sometimes
rural
in
nature
and
,
although
some
pollutants
disperse
only
____________________
,
others
travel
large
distances
in
the
atmosphere
and
have
regional
and
global
impacts
.
Many
of
the
world
?
s
____________________
communities
are
____________________
exposed
to
toxic
fumes
when
cooking
,
or
heating
and
lighting
their
homes
.
