Table 1: Irradiation D Value

Vegetative Organisms

Classification

kGy

Reference

Listeria monocytogenes

A

0.62

1

Salmonella sp.

B

0.6

2

E. coli O157:H7

B

0.3

2

Yersinia enterocolitica

B

0.2

2

Campylobacter sp.

B

< 0.2

2

Staphylococcus aureus

B

0.5

2

Brucella abortus

A/B

0.15

2

Salmonella muenster

A

0.6

3

Mycobacterium fortuitum

A

0.6

3

Clostridium difficile

A

0.9

3

Aspergillus fumigatus

A

0.6

3

Candida albicans

A

0.9

3

Streptococcus faecalis

A

1.56

3

Salmonella typhimurium

C

0.2 to 1.3

4

Pseudomonas spp.

C

0.06

4

Staphylococcus aureus

C

0.2

4

Streptococcus faecium

C

2.8 (dry)

4

Micrococcus radiodurans

C

2.2

4

Lactobacillus brevis

C

1.2

4

Acinetobacter radioresistens

C

1.3-2.2

4

Aspergillus niger

C

0.5

4

Saccharomyces cerevisiae

C

0.5

4

Anaerobic Spore Formers

Clostridium botulinum

C

1.4 to 4.2

4

Clostridium sporogenes

C

1.6 to 2.2

4

Clostridium tetani

C

2.4

4

Aerobic Spore Formers

Bacillus subtilis

C

0.6

4

Bacillus pumilus E-601

C

1.7

4

Bacillus pumilus E-601

C

3.0 (dry)

4

Bacillus pumilus ATCC 27142

C

1.4 to 1.8

4

Cryptococcus laurentiii

C

3.1

5

Cryptococcus albidus

C

2.7

5

C

1.4

5

Legend

A = Sewage/Lab Waste              B = Meat             C Wet or Dry                             

Table 2b: Effect of Gamma Irradiation on Viruses in Water or Serum

D-value kGy

Reference

Virus

Water

25% Fetal Calf Serum

100% Bovine Serum

100% Frozen Serum

Picorna

0.3

1.9

5.0

N/A

Reo

0.35

3.0

8.0

N/A

Parvo

0.4

4.5

10.7

N/A

Pox

0.2

1.0

N/A

N/A

HSV

0.17

0.4

N/A

N/A

SV40

3.9

N/A

N/A

26

Note:  Viruses are protected from destruction by irradiation by serum. Resistance is directly proportional to serum concentration. Frozen serum is even more protective than non- frozen serum.

Table 2a: Effect of Gamma Irradiation on Viruses

Virus

D-value kGy

Reference

Porcine Parvovirus

4.0

Picomavirus Swine Vesicular Disease

2.8

Adenovirus

4.5

Avian Pox

2.0

Newcastle Disease Virus

2.0

Foot and Mouth

13.0

Coxsackievirus

4.5

Notes

1. As a general rule the smaller the virus the more resistant to irradiation and there is no resistance pattern as one compared RNA with DNA.

2. Also, one notes a greater degree of radioresistance for viruses as compared to B, Y and M (see Table                      1).

Table 3: Germicidal Strength

Description

Isaac Newton said that you don’t know about a thing unless you can give it a number- This has been useful   in the earlier data as to providing meaningful data when measuring the RESISTANCE of specific organisms to ionizing radiation.

For chemical germicides the D-10 number features conversely the STRENGTH of a chemical agent as to its oxidizing or denaturing ability.

The following data were developed in our lab in studies designed to compare the strength of a variety of germicides against three spores of the genus Bacillus for purposes of comparative biology and for assessment of anthrax surrogate potential.

Germicide

Spore of Bacillus spp.

anthracis

cereus

subtilis

10% Bleach [Sodium hypochlorite]

4  minutes

4 minutes

5  minutes

3 % H₂O₂

1  minute

5  minutes

10  minutes

NaOH 0.5N

3 hours

3 hours

6 hours

Citric Acid 1.5% *

EPA Quat (750ppm)

1.5 hours

2.5 hours

6 hours

Iodophor 10% PVPI

10  minutes

15  minutes

15  minutes

Phenolic Amyl Phenyl Phenol

> 6  hours

> 6  hours

70% IPA

> 6  hours

> 6  hours

1. * More active at elevated Temperature

1. The B. subtilis endospore would best serve as the surrogate biological indicator in an anthrax germ warfare screening program being the most resistant species.

1. Studies with a potential viral germ warfare organism (Small pox as Vaccinia surrogate) showed the value of the D-10 quantal determination as follows in assessing the strength of household remedies.

     Agent                                     D-value

                                                   3 % H₂O₂                                        5 seconds
                                                   EPA Quat                                       5  seconds

                                                   70% IPA                                          5  seconds

                                                   70% EtOH                                       > 5  seconds