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EXAMPLE TEST REPORT #2
Formula Preservation

Report Transmittal and Recommendation

April 1, 1999

Mr./Mrs. Customer
Any Company
Any Town, USA

Dear Mr./Mrs. Customer,

Enclosed please find a copy of our microbiology laboratory report outlining preservation challenge test results conducted on your products containing Surcide G-50.

  • Fabric Softener - #1111
  • Hand Cleaner - #2233

Please note that Fabric Softener #1111 can be adequately preserved with 0.10% Surcide G-50 (0.05% was marginally acceptable) and Hand Cleaner #2233 can be adequately preserved with 0.15% Surcide G-50 (0.10% G-50 was marginally acceptable).

Please feel free to contact me if you have any questions.

Very truly yours,

Donald F. Greene
Microbiologist

SURCIDE G-50

TECHNICAL SERVICE LABORATORY REPORT

REPORT NUMBER: 123-456

COMPANY: Any Company, USA

SAMPLE(S):

  • 1. Fabric Softener #1111
  • 2. Hand Cleaner #2233

Contamination Check

The samples were evaluated for microbial content and found to be free of contamination. From the unpreserved samples, 100g samples were made containing various levels of Surcide G-50.

Preservation Test

Each 100g sample was inoculated weekly with 0.5mL of a mixed suspension of bacteria (including Pseudomonas) and fungi (molds and yeasts) (minimum inoculum count 108 bacteria/106 fungi per mL). The organisms used had all previously been isolated from contaminated products. These organisms (similar to the products tested in this study) are more resistant and adaptable than pure cultures obtained from the American Type Culture Collection (ATCC); therefore it is generally accepted that organisms of this type are most suitable for this kind of preservation challenge testing.

Prior to each inoculation, small samples of test material were streaked onto Nutrient Agar (for bacteria) and Sabouraud Dextrose Agar (for fungi). The plates were incubated at 32 ° C for 48 hours and 22 ° C for 5 days respectively and observed for growth. Growth on a plate was taken as indicative of failure.

In our experience, samples withstanding 6 inoculations by this method can be considered satisfactorily preserved against the organism tested and there is a high probability that the product will be "adequately preserved". It is impossible to determine if a product is adequately preserved against all types and strains of organism. However, positive results in this test are a very reliable indication of preservation activity during manufacture, use and storage.


Results

Number of Survivors Detected after Inoculation Number
Fabric Softener #1111 1 2 3 4 5 6
0.05% Surcide G-50 0 0 0 0 200 Bact

0 Fungi		 500 Bact

0 Fungi
0.100% Surcide G-50 0 0 0 0 0 0
0.150% Surcide G-50 0 0 0 0 0 0
0.20% Surcide G-50 0 0 0 0 0 0
Fabric Softener

Unpreserved Control		 0 10,000 Bact

1,000 Fungi
(Molds)		 100,000 Bact

10,000 Fungi
(Molds & Yeasts)		 1,000,000 Bact

10,000 Fungi
(Molds & Yeasts)		 1,000,000 Bact

10,000 Fungi
(Molds & Yeasts)		 1,000,000 Bact

10,000 Fungi
(Molds & Yeasts)
 
Hand Cleaner #2233 1 2 3 4 5 6
0.05% Surcide G-50 0 0 200 Bact

0 Fungi		 500 Bact

0 Fungi		 1,000 Bact

0 Fungi		 10,000 Bact

0 Fungi
(Molds)
0.10% Surcide G-50 0 0 0 0 100 Bact

0 Fungi		 100 Bact

0 Fungi
0.15% Surcide G-50 0 0 0 0 0 0
0.20% Surcide G-50 0 0 0 0 0 0
Hand Cleaner

Unpreserved Control		 0 Bact

1,000 Fungi
(Molds)		 1,000 Bact

1,000 Fungi
(Molds)		 10,000 Bact

10,000 Fungi
(Molds)		 100,000 Bact

> 10,000 Fungi		 > 1,000,000 Bact

> 10,000 Fungi
(Molds)		 > 1,000,000 Bact

> 10,000 Fungi
(Molds)

NOTE: 0 = <10 organisms/gram

Comments/Discussions:

Fabric Softener #1111

  • 0.05% Surcide G-50 – low levels of bacteria were detected after inoculations #5 and #6 – marginally acceptable
  • 0.10%, 0.15%, 0.20% Surcide G-50 – zero organisms were detected after all 6 inoculations – pass
  • unpreserved control – high levels of bacteria, molds, and yeasts were detected after inoculations #2, #3, #4, #5, and #6 – fail

Hand Cleaner #2233

  • 0.05% Surcide G-50 – low-moderate-high levels of organisms were detected after inoculations #3, #4, #5, and #6 - fail
  • 0.10% Surcide G-50 – low levels of bacteria were detected after inoculation #5 and #6 – marginally acceptable
  • 0.15%, 0.20% Surcide G-50 – zero organisms were detected after all 6 inoculations – pass

Conclusions:

  • Fabric Softener #1111 can be adequately preserved with 0.10% Surcide G-50 ……....
  • 0.05% G-50 was marginally acceptable
  • Hand Cleaner #2233 can be adequately preserved with 0.15% Surcide G-50 ………
  • 0.10% G-50 was marginally acceptable

 

Donald F. Greene
Microbiologist

April 1, 1999

The information and recommendations set forth are based on our own research and that of others, and to the best of our knowledge believed to be correct. Suggestions made concerning uses or application are only the opinion of Surety Laboratories, Inc. and you should make your own tests to determine the suitability of this information for your own particular purpose. However, because of numerous factors affecting results, Surety Laboratories, Inc. makes no warranty of any kind, expressed or implied. Statements herein therefore, should not be construed as representations or warranties of any kind.