Am.  Jour.  Pharm. 
May,  1884. 
Tin  in  Canned  Foods. 
271 
fully  washing  the  external  surfaces  of  a  mass  of  meat  just  removed 
from  a  can,  or  on  otherwise  properly  treating  canned  food  with  the 
object  of  detecting  such  particles.  The  published  processes  for  the 
detection  of  tin  in  canned  food  will  not  reveal  more  than  the  amounts 
stated  in  the  table,  or  about  those  amounts,  that  is  to  say,  a  few  thou- 
sandths, or  perhaps  two  or  three  hundredths  of  a  grain,  if  this  precau- 
tion be  adopted.  If  such  care  be  not  observed  the  less  minute  amounts 
may  be  found.  I  did  not  detect  any  metallic  particles  in  the  twelve 
samples  of  canned  food  just  mentioned,  but  during  the  past  few  years 
I  have  occasionally  found  small  pieces  of  metal,  perhaps  amounting  in 
some  of  the  cases  to  a  few  tenths  of  a  grain  per  pound.  Now  and  then 
small  shot-like  pieces  of  tin,  or  possibly  solder,  may  be  met  with.  But 
no  one  has  ever  found,  to  my  knowledge,  such  a  quantity  of  actual 
metallic  tin,  tinned  iron,  or  solder,  as,  from  the  point  of  view  of  health,, 
can  have  any  significance  whatever. 
The  largest  amount  of  tin  I  ever  detected  in  actual  solution  in  food 
was  in  some  canned  soup,  containing  a  good  deal  of  lemon  juice.  It 
amounted  to  only  three-hundredths  of  a  grain  in  a  half  pint  of  the 
soup  as  sent  to  table.  Now,  Christison  says  that  quantities  of  18  to 
44  grains  of  the  very  soluble  chloride  of  tin  were  required  to  kill  dogs 
in  from  one  to  four  days.  Orfila  says  that  several  persons  on  one 
occasion  dressed  their  dinner  with  chloride  of  tin,  mistaking  it  for  salt. 
One  person  would  thus  take  not  less  than  20  to  30  grains  of  this  solu- 
ble compound  of  tin.  Yet  only  a  little  gastric  and  bowel  disturbance 
followed,  and  from  this  all  recovered  in  a  few  days.  Pereira  says  that 
the  dose  of  chloride  of  tin  as  an  antispasmodic  and  stimulant  is  from 
-jig-  to  J  a  grain  repeated  two  or  three  times  daily.  Probably  no  article 
of  canned  food,  not  even  the  most  acid  fruit,  if  in  a  condition  in  which 
it  can  be  eaten,  has  ever  contained,  in  an  ordinary  table  portion,  as 
much  of  a  soluble  salt  of  tin  as  would  amount  to  a  harmless  or  useful 
medicinal  dose. 
Metallic  particles  of  tin  are  without  any  effect  on  man.  A  thousand 
times  the  quantity  ever  found  in  a  can  of  tinned  food  would  do  no 
harm. 
Food  as  acid  as,  say  ordinary  pickles,  would  dissolve  tin.  Some 
manufacturers  once  purposed  using  tin  stoppers  to  their  bottles  ot 
pickles.  But  the  tin  was  slowly  dissolved  by  the  acid  of  the  vinegar. 
These  pickles,  however,  had  a  distinctly  nasty  "  metallic"  flavor.  The 
idea  was  abandoned.    Probably  any  article  of  food  containing  enough 
