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b y
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nt
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T h
ed
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m
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rg
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i
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i t
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oi
m p
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i
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d
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rw
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m
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et
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m p
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s od
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n e c e s s a ri
l y i m p l
y
m
i
c r ob
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s af
et
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;
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a ny
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i
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i
nd
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e s.A p p
r o xi
m
at
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m
i
l l
i
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r e nd i
e of d i
a r rh
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of
r o ug h l y 2
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o n ch i l d h
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o e ac a s e s, o n a n a n n u a
l b
a si
s.W
at
e rb
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l l
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a c c o u nt
sf
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of
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h
s a nd
f i
v ep
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of
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t
h l
o s sd
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s ab
i
l
i t
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w
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i d
e;
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a r rh
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o n ei
s c o n si d
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t
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et
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i
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c o nt
ri
b
ut
ort
ot
h
eg l
ob
al b
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s e a s e(W
.H
O
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)
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u ch
of
t
h
i
sd i
s e a s e r e s ul
t
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r om
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n ad
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ep
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ed
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nk i
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nt
h
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ol d
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ai
l
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n s u ch
s af
ew
at
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ep
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rom
t
h
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l
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em
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s af
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el
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ot
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en e
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t
h
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ap p l
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s af
ew
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ert
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at
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e.T h i
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h
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ni
t
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m
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sy
st
em
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i
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and
ap p
r op
ri
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i
si
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w
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sm
all
s c a
l
e(
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ob
s ey 2 0 0
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,F
ew
t
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)
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y p
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u s e a nd
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l i
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, c o up l
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it
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nl
ow
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s(
C l
a s e n,2 0 0
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)
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ow
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h
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st
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ri
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ng
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,p
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i
nl
ow
-r e s o u -r c e c o n
t
e xt
s.C
o st i
s o n e;
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r a nte
d
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f f
i c a cy
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l
it
y
, a nd
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el
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t
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o od
i
nt
h
ef
o rm
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e-u s e ch
em i
c al d i
si
nf
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.
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u r ab
i
l
i t
y
a nd m
ob i l i
t
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s oi
s s u e s;
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m
et
h
od
w
h
o s el
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u rd
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t
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st i
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f fi
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n r e s o u r c e-l
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m
it
ed
a nd h
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it i
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n a r el
at
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h
em
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nw
h
i
ch
am
et
h
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i
s u s ed m
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i
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nt
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t ;
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w
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ch
r eq
ui
r e ah i g h d
eg
r e e of
ed
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i
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t
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s e x c e s si
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nt
ri
c at
ew
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l
i
k
ely b
el
i
m
it
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n ap
p
l
i
cab
i
l
it
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.F
i
n al l y
, c o n s um
e r a c c ep
t
ab
i
l
i t
y
i
s ak
ey
c o n si
d
erat
i
o n.W
i t
h
o ut
a c
tu a
l
up
t
ak
e a nd
c o nt
i
n u ed
ef f
e ct
i
v e u s e, e v e nt
h
em
o st
l
ab
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o ry
-e
f f
e ct
i
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at
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m
e nt
sw
i l l
f
ai
l
t
o r e al
i
s et
h
ei
rf
ul l p
ot
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al
i
nt
h
efi
el d
.C
u r r e nt
ly
a v ai l
ab l
em
et
h
od
sf
o r s o -c al l
ed
"
P
oi
nt
of U
s eH
o u s eh
ol d
"[
P O U H
)
w
at
e rt
r e at
m
e nt
f
ai l
o ra r e
d
efi
ci
e nt
i
n o n e, o rm
o r e of
t
h
e ab
o v e c ri
t
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a.F
r e e ch l
o ri
n e, aw
i d
el y
u s ed
a nd m
od
e r at
el y
e
f f
e ct i
v ed
i
si
nf
ect
a nt
,h
a sm
a ny
u nd
e si
r ab l
eq
u al
i t i
e s(
e.g
. ch
em
i
c al
v ol
at i
l
i t
y
, u n