Section 490.70. Limitations

1.  The provisions of sections 490.37, 490.40, 490.45, 490.47, 490.50,
  and 490.55 of this article shall not apply where the defendant possessed
  or used:
    (a) any household product generally available for sale to consumers in
  this state in the quantity and concentration available for such sale;
    (b) a self-defense spray device in accordance with the  provisions  of
  paragraph fourteen of subdivision a of section 265.20 of this chapter;
    (c)  a  chemical weapon solely for a purpose not prohibited under this
  chapter, as long as the type and quantity  is  consistent  with  such  a
  purpose; or
    (d)   a  biological  agent,  toxin,  or  delivery  system  solely  for
  prophylactic,  protective,  bona  fide  research,  or   other   peaceful
  purposes.
    2.  For  the  purposes  of  this  section,  the  phrase  "purposes not
  prohibited by this chapter" means the following:
    (a) any peaceful  purpose  related  to  an  industrial,  agricultural,
  research,   medical,   or  pharmaceutical  activity  or  other  peaceful
  activity;
    (b) any purpose directly related to protection against toxic chemicals
  and to protection against chemical weapons;
    (c) any military purpose of the United States that  is  not  connected
  with the use of a chemical weapon or that is not dependent on the use of
  the  toxic or poisonous properties of the chemical weapon to cause death
  or other harm; and
    (d) any law enforcement purpose, including any domestic  riot  control
  purpose and including imposition of capital punishment.