AmAp?lir ip?9.rm*  }  Use  of  Boric  Acid  as  a  Disinfectant. 
207 
the  proteus  group  of  bacteria.  Members  of  the  B.  coli  group  were 
not  affected.  Strassburger4  found  the  same  selective  action.  This 
investigator  states  some  organisms  are  able  to  stand  large  doses  of 
boric  acid  with  impunity  while  others  find  small  doses  very  toxic. 
Agullion5  found  that  this  chemical  in  saturated  solutions  had  little 
retarding  effect  on  the  activity  of  enzymes.  E'we  and  Vander- 
kleed6  have  stated  that  two  grains  of  boric  acid  would  preserve  a 
sample  "of  urine  for  six  days,  whereas  the  control  sample  spoiled  in 
three  days.  Kuehle7  found  that  B203  was  a  very  feeble  antiseptic 
and  in  no  way  had  the  ability  to  check  undesirable  bacterial  change. 
Such  are  the  impressions  which  one  is  able  to  get  from  the  literature 
concerning  this  subject. 
Ochsner8  stated  that  this  chemical  did  not  destroy  pathogenic 
bacteria  but  did  diminish  their  virulence. 
Experimental. 
No  attempt  was  made  to  carry  out  an  exhaustive  investigation 
on  boric  acid  as  a  disinfectant.  An  attempt  was  made,  however, 
to  determine  just  how  toxic  a  solution  of  boric  acid  was  toward 
bacteria.  To  do  this,  a  saturated  solution  in  distilled  water  was 
used.  Chemical  handbooks  state  that  such  a  solution  of  this  acid 
approaches  a  4  per  cent,  solution.  Such  solutions  are  generally 
used  in  disinfection. 
The  first  experiment  consisted  in  adding  increasing  amounts  of 
boric  acid  to  melted  dextrose  agar  and  allowing  the  tubes  to  harden 
in  the  slanted  position.  After  that  the  slants  were  inoculated  by 
streaking  and  incubated.  The  incubation  period  was  four  days  at 
370  C.  after  which  the  culture  tubes  were  observed.  The  results 
with  common  bacteria  are  given  in  Table  I.  The  signs  used  therein 
have  the  following  values:  ++  —  normal  growth  determined  from 
an  untreated  agar  culture;  +  =  growth;  —  =  no  growth. 
4  Strassburger,  F.,  Boric  Acid  as  a  Preservative  with  Reference  to  Its  Use 
in  the  preserving  of  Crabs,  Hyg.  Rund.,  19,  169-85. 
5  Agullion,  H.,  The  Influence  of  Boric  Acid  on  the  Action  of  Diastasic 
Ferments,  Ann.  Past.  Inst.,  29,  495-518.    Chem.  Absts.,  5,  1911,  1788. 
6  E'we,  G.  E.,  and  Vanderkleed,  C.  E.,  Boric  Acid  as  a  Preservative  for 
Urine  Analysis,  /.  Amer.  Pharm.  Assoc.,  2,  979-982. 
7  Kuehle,  H.,  Boric  Acid  as  a  Preservative,  Pharm.  Centr.,  50,  559. 
8  Ochsner,  E.  H.,  The  Biochemistry  of  Topical  Applications  with  Special 
Reference  to  the  Use  of  Boric  Acid  in  Septic  Infections,  Chemical  Abstracts, 
12,  1918,  191. 
