EXHIBIT 10.1

                        THIRD AMENDMENT TO LOAN AGREEMENT

         THIS THIRD AMENDMENT (this "AMENDMENT") is made as of this 27th day of
February, 2002, by and among SystemOne Technologies Inc. (f/k/a Mansur
Industries Inc.), a Florida corporation (the "BORROWER"), Hanseatic Americas LDC
("HANSEATIC"), Environmental Opportunities Fund II, LP ("ENVIRONMENTAL II") and
Environmental Opportunities Fund II (Institutional), LP ("ENVIRONMENTAL
INSTITUTIONAL", collectively with Hanseatic and Environmental II, the
"LENDERS").

                                    RECITALS

         WHEREAS, the Borrower and the Lenders are parties to that certain Loan
Agreement dated August 7, 2000, as amended by a First Amendment to Loan
Agreement dated as of November 10, 2000 and a Second Amendment to Loan Agreement
dated as of November 30, 2000 (as amended, the "LOAN AGREEMENT"); and

         WHEREAS, the Borrower and the Lenders desire to amend the Loan
Agreement to (i) change the Maturity Date (as defined in the Loan Agreement)
from February 7, 2002 to September 30, 2002, and (ii) change the terms upon
which the Borrower will issue the Additional Warrants (as defined in the Loan
Agreement) to the Lender;

         NOW, THEREFORE, in consideration of the premises and for other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto agree as follows:

         1. Article I, Section 1.1 (xxxvi) of the Loan Agreement is hereby
amended by deleting Article I, Section 1.1 (xxxvi) in its entirety and
substituting therefor a new Article I, Section 1.1 (xxxvi) to read as follows:

                           (xxxvi) The term "MATURITY DATE" shall mean September
30, 2002.

         2. Article II, Section 2.10 of the Loan Agreement is hereby amended by
deleting the second sentence of Article II, Section 2.10 in its entirety and
substituting therefor a new sentence to read as follows:

                  In addition, in the event that the Borrower does not
punctually satisfy the Note on or prior to February 28, 2002 and after such date
the Borrower (i) sells debt or equity securities, or debt securities convertible
into equity securities, or incurs debt with a final scheduled maturity date more
than twelve months after issuance or incurrence providing gross cash proceeds to
the Borrower in an amount equal to or greater than the outstanding principal
amount and accrued interest of the Notes on the date of such sale or incurrence,
or (ii) enters into a merger, consolidation, sale of all or substantially all of
its assets or other business combination transaction with a party that prior to
such transaction owns less than 25 percent of the voting power of the Borrower's
outstanding equity securities, then upon the consummation of the earliest of any
such transaction, the Borrower shall forthwith issue and deliver to each of the
original holders of the Notes a number of additional warrants (hereinafter, with
respect to all Lenders, referred to as the "Additional Warrants") to purchase
shares of Common Stock (hereinafter with respect to all Lenders referred to as





the "Additional Warrant Shares") equal to the number of Initial Warrants to such
original holder, such Additional Warrants to be evidenced by warrant
certificates (hereinafter referred to, collectively, as the "Additional Warrant
Certificates"), each registered in the name of such original holder and dated
the date of issuance thereof, in the form of the Initial Warrant Certificate
(except that all such Additional Warrants shall be immediately exercisable, and
provided that the terms of the Additional Warrants as aforesaid shall, for
purposes of issuance thereof and without limiting the operation thereof, be
subject to adjustment pursuant to Section 6 of the form of Initial Warrant
Certificate as if in effect from and after the Closing Date).

         3. Except as specifically amended hereby, the Loan Agreement is and
remains unmodified and in full force and effect and is hereby ratified and
confirmed.

         4. This Amendment shall be deemed a contract made under the laws of the
State of New York and for all purposes shall be governed by and construed in
accordance with the laws of such State applicable to contracts made and to be
performed entirely within such State.

         5. This Amendment may be executed in counterparts and each of such
counterparts shall for all purposes be deemed to be an original, and such
counterparts shall constitute but one and the same instrument.



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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed as of the date first above written.

SYSTEMONE TECHNOLOGIES INC.


By: /s/ PAUL I. MANSUR
    ----------------------------------------
     Paul I. Mansur
     Chief Executive Officer

LENDERS

HANSEATIC AMERICAS LDC

By:  Hanseatic Corporation

By: /s/ PAUL A. BIDDELMAN
    --------------------------------
     Paul A. Biddelman
     President

ENVIRONMENTAL OPPORTUNITIES FUND II, L.P.
ENVIRONMENTAL OPPORTUNITIES FUND II (INSTITUTIONAL), L.P.

By:  Fund II Mgt. Co., LLC
General Partner

By: /s/ KENNETH C. LEUNG
    --------------------------------
     Kenneth C. Leung
     Chief Investment Officer


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