Deactivation of organisms using high-intensity pulsed polychromatic light

Abstract

A method of deactivating microorganisms in food products, packaging material, water, air, and other products involves illuminating the microorganisms using at least one short-duration, high-intensity pulse of broad- spectrum polychromatic light. In variations of this embodiment, the light has an intensity of at least 0.1 J/cm 2 , the pulse duration is from between about 10 nanoseconds and 10 milliseconds, and/or at least 50% of the at least one pulse's energy is transmitted in light having wavelength from between about 170 and 2600 nanometers. Advantageously, the microorganisms may be Cryptosporidium parvum oocysts, Bacillus pumilus spores or poliovirus.

What is claimed is:  
     
         1 . A method of deactivating a virus comprising: 
 illuminating the virus using at least one short-duration, high- intensity pulse of broad spectrum polychromatic light.    
     
     
         2 . The method of  claim 1  wherein said illuminating includes: 
 illuminating said virus using said at least one short-duration, high-intensity pulse of broad spectrum polychromatic light having an intensity of at least 0.1 J/cm 2 .  
 
     
     
         3 . The method of  claim 2  wherein said illuminating includes: 
 illuminating said virus using said at least one short-duration, high-intensity pulse of broad spectrum polychromatic light, having a pulse duration of from between about 10 nanoseconds and 10 milliseconds.  
 
     
     
         4 . The method of  claim 3  wherein said illuminating includes: 
 illuminating said virus using said at least one short duration, high intensity pulse of broad spectrum polychromatic light, said pulse having at least 50% of its energy transmitted in light having wavelength from between about 170 and 2600 nanometers.  
 
     
     
         5 . The method of  claim 1  wherein said illuminating includes: 
 illuminating poliovirus using at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light.  
 
     
     
         6 . A method of decontaminating air containing microorganisms comprising: 
 illuminating the microorganisms contained in the air using at least one short- duration, high-intensity pulse of broad spectrum polychromatic light.    
     
     
         7 . The method of  claim 6  wherein said illuminating includes: 
 illuminating said air using said at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light, having an intensity of at least 0.1 J/cm 2 .  
 
     
     
         8 . The method of  claim 7  wherein said illuminating includes: 
 illuminating said air using said at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light, having a pulse duration of from between about 10 nanoseconds and 10 milliseconds.  
 
     
     
         9 . The method of  claim 8  wherein said illuminating includes: 
 illuminating said air using said at least one short-duration, high intensity pulse of broad-spectrum polychromatic light, said pulse having at least 50% of its energy transmitted in light having wavelength from between about 170 and 2600 nanometers.  
 
     
     
         10 . The method of  claim 6  wherein said illuminating includes: 
 illuminating a plurality of  Bacillus pumilus  spores in said air using said at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light.  
 
     
     
         11 . The method of  claim 6  further comprising: 
 flowing said air into a treatment zone;  
 said illuminating said air including illuminating said air within the treatment zone using said at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light.  
 
     
     
         12 . The method of  claim 11  further comprising: 
 flowing said air, having been illuminated, out of said treatment zone.  
 
     
     
         13 . The method of  claim 12  wherein said flowing said air into said treatment zone includes continuously flowing said air into said treatment zone, and wherein said flowing said air out of said treatment zone includes continuously flowing said air out of said treatment zone.  
     
     
         14 . The method of  claim 13  wherein further comprising: 
 repeating said illuminating at a flash repetition rate sufficiently high that all of said air is illuminated at least once as it passes through said treatment zone.  
 
     
     
         15 . The method of  claim 14  wherein said illuminating includes: 
 illuminating said air using at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light, having an intensity of at least 0.1 J/cm 2 .  
 
     
     
         16 . The method of  claim 15  wherein said illuminating includes: 
 illuminating said air using at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light, having a pulse duration of from between about 10 nanoseconds and 10 milliseconds.  
 
     
     
         17 . The method of  claim 16  wherein said illuminating includes: 
 illuminating said air using at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light, said pulse having at least 50% of its energy transmitted in light having wavelength from between about 170 and 2600 nanometers.  
 
     
     
         18 . The method of  claim 17  wherein said illuminating includes: 
 illuminating a plurality of  Bacillus pumilus  spores in the air using said at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light.  
 
     
     
         19 . A method of deactivating protozoa comprising: 
 illuminating the protozoa using at least one short-duration, high-intensity pulse of broad spectrum polychromatic light.    
     
     
         20 . The method of  claim 19  wherein said illuminating includes: 
 illuminating said protozoa using said at least one short-duration, high-intensity pulse of broad spectrum polychromatic light having an intensity of at least 0.1 J/cm 2 .  
 
     
     
         21 . The method of  claim 20  wherein said illuminating includes: 
 illuminating said protozoa using said at least one short-duration, high-intensity pulse of broad spectrum polychromatic light, having a pulse duration of from between about 10 nanoseconds and 10 milliseconds.  
 
     
     
         22 . The method of  claim 21  wherein said illuminating includes: 
 illuminating said protozoa using said at least one short duration, high intensity pulse of broad spectrum polychromatic light, said pulse having at least 50% of its energy transmitted in light having wavelength from between about 170 and 2600 nanometers.  
 
     
     
         23 . The method of  claim 19  wherein said illuminating includes: 
 illuminating a plurality of  Cryptosporidium parvum  oocysts using at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light.  
 
     
     
         24 . A method of decontaminating water containing cyst-forming protozoa comprising: 
 illuminating the water using at least one short-duration, high-intensity pulse of broad spectrum polychromatic light.    
     
     
         25 . The method of  claim 24  wherein said illuminating includes: 
 illuminating said water using said at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light, having an intensity of at least 0.1 J/cm 2 .  
 
     
     
         26 . The method of  claim 25  wherein said illuminating includes: 
 illuminating said water using said at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light, having a pulse duration of from between about 10 nanoseconds and 10 milliseconds.  
 
     
     
         27 . The method of  claim 26  wherein said illuminating includes: 
 illuminating said water using said at least one short-duration, high intensity pulse of broad-spectrum polychromatic light, said pulse having at least 50% of its energy transmitted in light having wavelength from between about 170 and 2600 nanometers.  
 
     
     
         28 . The method of  claim 24  wherein said illuminating includes: 
 illuminating a plurality of  Cryptosporidium parvum  oocysts in said water using said at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light.  
 
     
     
         29 . The method of  claim 24  further comprising: 
 flowing said water into a treatment zone;  
 said illuminating said water including illuminating said water within the treatment zone using said at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light.  
 
     
     
         30 . The method of  claim 29  further comprising: 
 flowing said water, having been illuminated, out of said treatment zone.  
 
     
     
         31 . The method of  claim 30  wherein said flowing said water into said treatment zone includes continuously flowing said water into said treatment zone, and wherein said flowing said water out of said treatment zone includes continuously flowing said water out of said treatment zone.  
     
     
         32 . The method of  claim 31  wherein further comprising: 
 repeating said illuminating at a flash repetition rate sufficiently high that all of said water is illuminated at least once as it passes through said treatment zone.  
 
     
     
         33 . The method of  claim 32  wherein said illuminating includes: 
 illuminating said water using at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light, having an intensity of at least 0.1 J/cm 2 .  
 
     
     
         34 . The method of  claim 33  wherein said illuminating includes: 
 illuminating said water using at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light, having a pulse duration of from between about 10 nanoseconds and 10 milliseconds.  
 
     
     
         35 . The method of  claim 34  wherein said illuminating includes: 
 illuminating said water using at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light, said pulse having at least 50% of its energy transmitted in light having wavelength from between about 170 and 2600 nanometers.  
 
     
     
         36 . The method of  claim 35  wherein said illuminating includes: 
 illuminating a plurality of  Cryptosporidium parvum  oocysts in the water using said at least one short-duration, high-intensity pulse of broad-spectrum polychromatic light.  
 
     
     
         37 . A system for deactivating microorganisms in water comprising: 
 an watertight housing;    an inlet port of the watertight housing;    an outlet port of the watertight housing;    a tubular light source positioned within the watertight housing; and    a tubular baffle positioned within the watertight housing for directing a substantially uniform flow of water in a direction substantially parallel to the light source.    
     
     
         38 . The system of  claim 37  wherein: 
 said tubular baffle has a first and a second end; and  
 said inlet port and said outlet port are positioned proximate for the first end of the tubular baffle.  
 
     
     
         39 . The system of  claim 38  wherein: 
 said tubular baffle directs said water from said inlet port in a direction substantially antiparallel to said light source, and directs said water to said outlet port in a direction substantially parallel to said light source.  
 
     
     
         40 . The system of  claim 39  wherein: 
 said inlet port is positioned to flow water into said tubular housing from outside said tubular baffle; and  
 said outlet port is positioned to withdraw water from said tubular housing from inside said tubular baffle, said water flowing around said second end of said tubular baffle.  
 
     
     
         41 . The system of  claim 37  wherein: 
 said light source is positioned substantially along a central axis of said tubular baffle.  
 
     
     
         42 . The system of  claim 41  wherein: 
 said tubular baffle is substantially cylindrical.  
 
     
     
         43 . The system of  claim 41  wherein: 
 said tubular housing is substantially cylindrical.  
 
     
     
         44 . The system of  claim 37  wherein said outlet port is oriented to expose an interior surface thereof to light emitted from the light source.  
     
     
         45 . The system of  claim 44  wherein said outlet port includes a frustoconical inner surface.