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| Waiver and Eighth Amendment to Loan Documents |   |
|-----------------------------------------------|--------|

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| [CORPORATE SEAL]            |               | STRATEGIC DIAGNOSTICS INC.       |
|-----------------------------|--------------------|----------------------------------|
|                        |               |                             |   |   |
| Attest:                     | /s/ Hilary R. Bond |                             | By: | /s/ Stanley Franczkowski |
|                        |               |                             |   |   |
| Print Name: Hilary R. Bond  |               | Print Name: Stanley Franczkowski |
|                        |               |                             |   |   |
| Title: Coordinator, Finance |               | Title: Chief Financial Officer   |
|                        |               |                             |   |   |
|                        |               |                             | PNC BANK, DELAWARE |
|                        |               |                             |   |   |
|                        |               |                             | By: | /s/ Warren C. Engle |
|                        |               |                             |   |   |
|                        |               |                             | Print Name: Warren C. Engle |
|                        |               |                             |   |
|                        |               |                             | Title: Senior Vice President |

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|   |                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|--------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| A.     | The “Loan Documents” that are the subject of this Amendment include the following (as any of the foregoing have previously been amended, modified or otherwise supplemented): |
|   |                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|   | 1.                                                                                                                                                                                        | Loan Agreement dated May 5, 2000, as amended by an Amendment to Loan Documents dated December 13, 2001, a Second Amendment to Loan Documents dated as of April 25, 2002, a Third Amendment to Loan Documents dated as of October 24, 2002, a Fourth Amendment to Loan Documents dated as of February 11, 2003, a Fifth Amendment to Loan Documents dated as of February 16, 2004, a Sixth Amendment to Loan Documents dated as of September 16, 2005 and a Seventh Amendment to Loan Documents dated as of August 21, 2007 (the “Loan Agreement”) |
|   |                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|   | 2.                                                                                                                                                                                        | Committed Line of Credit Note dated May 5, 2000, as amended in the maximum principal amount of $5,000,000.00 (the “Line of Credit Note”)                                                                                                                                                                                                                                                                                                                                                                                                          |
|   |                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|   | 3.                                                                                                                                                                                        | Term Note B dated December 13, 2001 in the original principal amount of $1,500,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|   |                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|   | 4.                                                                                                                                                                                        | Term Note dated August 21, 2007 in the original principal amount of $2,000,000.                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|   |                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|   | 5.                                                                                                                                                                                        | Working Cash®, Line of Credit, Investment Sweep Rider dated May 5, 2000, as amended                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|   |                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|   | 6.                                                                                                                                                                                        | Mortgage, Assignment of Rents, Security Agreement and Fixture Filing dated May 5, 2000                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|   |                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|   | 7.                                                                                                                                                                                        | Assignment of Rents and Leases dated May 5, 2000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|   |                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|   | 8.                                                                                                                                                                                        | Mortgage, Assignment of Rents, Security Agreement and Fixture Filing dated December 13, 2001                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|   |                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|   | 9.                                                                                                                                                                                        | Security Agreement dated May 5, 2000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|   |                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|   | 10.                                                                                                                                                                                       | Patent Security Agreement dated May 5, 2000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|   |                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|   | 11.                                                                                                                                                                                       | Trademark Security Agreement dated May 5, 2000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|   |                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|   | 12.                                                                                                                                                                                       | Rider to Security Rider – Patents dated May 5, 2000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|   |                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|   | 13.                                                                                                                                                                                       | Rider to Security Rider – Trademarks dated May 5, 2000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|   |                                                                                                                                                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|   | 14.                                                                                                                                                                                       | All other documents, instruments, agreements, and certificates executed and delivered in connection with the Loan Documents listed in this Section A.                                                                                                                                                                                                                                                                                                                                                                                                         |

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|   |                                                                                                                                                                                                                                                                                                                                                   |                                             |
|--------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------|
|   | 1.       The Expiration Date, as set forth in the Line of Credit Note, is hereby extended, effective September 1, 2008, from August 31, 2008 to August 31, 2009, on which date, unless extended as provided in the Note, the entire principal balance and any accrued but unpaid interest shall be due and payable. |
|   |                                                                                                                                                                                                                                                                                                                                                   |                                             |
|   | 2.                                                                                                                                                                                                                                                                                                                                                     | The Loan Agreement is hereby amended as follows: |
|   |                                                                                                                                                                                                                                                                                                                                                   |                                             |
|   | (a)        The Applicable Margin chart contained in Section 1.2 of the Loan Agreement is hereby amended and restated in its entirety to read as follows:                                                                                                                                                       |

| Ratio of FundedDebt to EBITDA |   | Applicable MarginLine of Credit |
|-------------------------------|--------|---------------------------------|
|                          |   |                            |
| ≥3:00: 1.0              |   | 250 basis points                |
| <3:00 ≥2.75          |   | 225 basis points                |
| <2.75 ≥2.50          |   | 200 basis points                |
| <2.50 ≥2.25          |   | 175 basis points                |
| <2.25                      |   | 150 basis points                |

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|   |   |                                                                 |
|--------|--------|----------------------------------------------------------------------|
|   | 1.     | Execution by all parties and delivery to the Bank of this Amendment. |