6o 
Japanese  Lac. 
/  Am.  Jour.  Pharm. 
\    February,  1906. 
Water  . 
Gum 
Laccasse 
Ash  .  . 
74*     per  cent. 
84-95 
2*50 
From  the  preceding  work  it  seems  to  me  that  I  am  justified  in 
saying  that  what  he  estimated  as  ammonia  was  not  ammonia  but 
pyrrol. 
The  Poisonous  Principle  and  its  Action. — Prof.  J.  J.  Rein  describes 
the  lac  poisoning  as  follows:1  "It  is  a  peculiar,  not  very  painful, 
and  not  at  all  fatal,  but  always  a  disagreeable  disease,  always  attack- 
ing any  one  new  to  the  work.  It  appears  in  a  mild  reddening  and 
swelling  of  the  back  of  the  hands,  the  eyelids,  ears,  the  navel  and 
lower  part  of  the  body,  especially  the  scrotum.  In  all  these  parts 
great  heat  is  felt  and  violent  itching  and  burning,  causing  many 
sleepless  nights.  In  two  or  three  days  the  crisis  is  reached,  and  the 
swelling  immediately  subsides.  In  severe  cases  small  festering  boils 
form  also.  This  lacquer  disease  is  not  only  caused  by  handling  of 
the  lac,  but  by  its  evaporation  chiefly,  especially  that  of  the  sharp 
Se-shime,  to  which  I  owe  my  own  illness.  .  .  .  The  poison, 
however,  is  a  volatile  substance,  and  has  nothing  to  do  with  the  lac 
acid  in  its  higher  oxidation,  as  Korschelt  believed.  If  the  poisonous 
property  disappears  in  the  drying  of  the  plant,  this  amounts  to 
nothing  save  that  the  volatile  poison  fully  escapes  in  this  manner. 
A  considerable  part  of  it  is  driven  off  in  the  preparation  of  the 
several  kinds  of  lacquer,  and  by  stirring  in  open  vessels.  For  this 
reason,  the  lacquers  mixed  with  colors  are  regarded  far  less  danger- 
ous than  the  raw  lac  and  its  derivatives.  When  such  lac  has  been 
for  a  long  time  shut  up  in  a  closed  box  or  tub,  the  experienced 
workman  turns  away  his  face  when  the  vessel  is  opened  that  he  may 
not  inhale  the  accumulated  vapors." 
Yoshida  also  states  that  the  lac  contains  a  volatile  poison  which 
is  dissolved  with  the  urushic  acid  by  alcohol,  but  is  almost  com- 
pletely driven  off  by  drying  the  acid  at  1050  C.  to  no°  C.  Ber- 
trand  2  says  that  the  lac  must  be  handled  with  the  greatest  precau- 
tion, because  the  least  traces  in  the  state  of  vapor  produce  on  the 
face,  hands  and  arms  an  intense  rubefaction,  accompanied  by  m- 
1  "  The  Industries  of  Japan, '?  p.  349. 
2  Annal.  de  Chem.  et  de  Phys.,  Series  XII,  1897. 
