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When  Is  Poison  Not  a  Poison? 
Am.  Jour.  Pharm. 
May,  1920. 
externally  or  taken  internally.  In  other  words,  it  is  not  then  a 
poison. 
This  leads  to  the  question:  "Can  a  substance  be  considered  as  a 
poison  at  one  time  and  innocuous  at  another?"  To  this  one  might 
make  several  replies,  as  the  problem  is  viewed  from  its  several  side- 
angles. 
For  example,  sulphuric  acid,  in  concentrated  form,  applied  to  the 
skin  or  taken  internally,  will  at  once  disintegrate  flesh.  Its  action 
is  then  that  of  a  corrosive  agent,  its  destructive  influence  resting 
directly  upon  avidity  for  water  and  its  power  of  abstracting  water 
from  liquids  and  even  from  tissue,  to  the  tissue's  complete  destruc- 
tion.   It  thus,  under  these  conditions,  becomes  a  corrosive  poison. 
As  an  example,  one  might  state  that  white  sugar  is  a  carbohy- 
drate, composed  of  carbon  and  the  elements  of  water  in  the  pro- 
portion to  theoretically  produce  water.  Place  a  lump  of  white  sugar 
on  a  plate  and  then  pour  upon  it  a  little  concentrated  sulphuric  acid. 
Immediately  it  turns  yellow,  then  black,  owing  to  the  liberation 
of  carbon  (charcoal)  by  the  abstraction  of  its  companion  oxygen 
and  hydrogen,  which  the  acid  takes,  to  the  destruction  of  the  sugar. 
Dilute  the  same  amount  of  sulphuric  acid  with  water,  to  pleasant 
acidity,  and  it  no  longer  destroys  tissue  on  contact  therewith,  nor 
is  it  immediately  harmful  to  the  stomach.  The  sugar  dissolves  in 
it,  colorless,  when  it  is  thus  diluted.  Indeed,  as  an  acidulated 
drink  (circus  lemonade),  much  diluted  and  flavored  with  lemon  oil, 
it  has  been  used,  without  immediate  corrosive  effect  or  injury,  as  a 
substitute  for  lemonade.  This  practice,  however,  is  now  wisely 
forbidden. 
To  sum  up,  in  one  form,  sulphuric  acid  is  destructive  to  living 
tissue;  in  another  form  (dilute),  it  acts  differently.  The  amount 
that,  concentrated,  would  disintegrate  tissue  if  applied  locally,  is, 
when  diluted,  harmless. 
Take  next  arsenic.  With  the  normal  human  being,  arsenic,  in 
comparatively  small  doses,  is  death-dealing.  But  with  some  per- 
sons, artificially  made  immune,  a  dose  that  poisons  others  is  harmless. 
Arsenic  eaters  come  within  the  scope  of  habit-forming  drug  addicts. 
The  habit-formed  principle  applies  likewise  to  morphine  and  similar 
drugs.  Be  the  arsenic  or  morphine  dilute  or  concentrated,  a  toxic 
amount  to  the  normal  man  acts  as  a  poison.  Be  it,  for  example, 
six  grains  of  morphine,  in  substance,  or  six  grains  dissolved  in  an 
ounce  of  water,  the  same  exerts  its  poisonous  influence,  providing 
