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                                                                EXHIBIT 10(i)(1)

                          AMENDED SUBLICENSE AGREEMENT

Amended agreement made this 23rd day of September, 1993 by and between U.S.
Alcohol Testing of America, Inc. ("USAT") and U.S. Drug Testing, Inc. ("USD")
each with executive offices at 10410 Trademark Street, Rancho Cucamonga,
California 91730.

        WHEREAS, USAT is a party to a license agreement with the U.S.
Department of the Navy dated January 24, 1992 granting USAT a partial exclusive
patent license to products for drug testing in the United States and certain
foreign countries; and

        WHEREAS, said license applies to the U.S. Government owned invention
known as a Flow Immunosensor Method and Apparatus; and

        WHEREAS, USAT has organized a wholly owned subsidiary, USD to conduct
research and development and to develop and enhance products for the detection
of drugs of abuse; and

        WHEREAS, the parties are desirous of having USD assume all rights and
undertake all obligations of USAT under the license agreement; and

        WHEREAS, this sublicense agreement will supersede the Agreement dated
the second day of January, 1993 by and between USAT and USD;

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        NOW, for good and valuable consideration including the issuance of all
outstanding USD shares to USAT and the execution of a management agreement
between the parties;

        IT IS AGREED that USD, subject to the approval of the U.S. Department
of Navy, will be the sole and exclusive sublicensee of USAT under the 
January 24, 1992 license agreement.

        IT IS FURTHER AGREED that this sublicense shall automatically be
modified or terminated in whole or in part upon the modification or termination
in whole or in part of the January 24, 1992 license, and that the Government 
retains rights of the type specified in Article VII of the January 24, 
1992 license.


                                   U.S. ALCOHOL TESTING OF AMERICA INC.

                                   By:       /s/ James C. Witham
                                      ---------------------------------
                                                 James C. Witham

                                   Date: 9/23/93
                                        -------------------------------

                                   U.S. DRUG TESTING, INC.

                                   By:       /s/ Douglas Allen
                                      ---------------------------------
                                                 Douglas Allen

                                   Date: 9/23/93
                                        -------------------------------

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