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                                                                    EXHIBIT 10.1

                         CONSENT AND FIRST AMENDMENT TO
                           LOAN AND SECURITY AGREEMENT

                                          July 25, 2003

WELLS FARGO FOOTHILL, INC., as Agent and Lender
One Boston Place, 18th Floor
Boston, Massachusetts 02108

Ladies and Gentlemen:

         Wells Fargo Foothill, Inc., as Arranger and Administrative Agent
("Agent") and Lender ("Foothill"), Ableco Finance LLC ("Ableco"; and together
with Foothill, "Lenders") and Advanced Lighting Technologies, Inc., an Ohio
corporation and a debtor and debtor-in-possession ("Parent") and each of
Parent's Subsidiaries identified as a borrower on the signature pages hereof
(such Subsidiaries, together with Parent, are referred to hereafter each
individually as a "Borrower", and individually and collectively, jointly and
severally, as "Borrowers") have entered into certain financing arrangements
pursuant to the Loan and Security Agreement dated June 30, 2003 among Agent,
Lenders, Borrowers and the other Loan Parties (as the same now exists or may
hereafter be amended, modified, supplemented, extended, renewed, restated or
replaced, the "Loan Agreement") and all other Loan Documents at any time
executed and/or delivered in connection therewith or related thereto. All
capitalized terms used herein shall have the meaning assigned thereto in the
Loan Agreement, unless otherwise defined herein.

         Borrowers have requested that Agent and Lenders consent to the
intercompany loan to be made by DSI to ADLT Realty in the amount of $8,000, the
proceeds of which shall be used by ADLT Realty to make certain payments due and
owing to Midland Loan Services, Inc. and to amend Schedule 5.20 (Permitted
Indebtedness) of the Loan Agreement in connection therewith. Agent and Lenders
are willing to agree and do hereby consent to the foregoing, on and subject to
the terms and conditions contained in this Consent and First Amendment to Loan
and Security Agreement (this "Amendment").

         In consideration of the foregoing and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged by
the parties hereto, the parties hereto hereby agree as follows:

         1.       AMENDMENT TO LOAN AGREEMENT. Schedule 5.20 (Permitted
Indebtedness) to the Loan Agreement is hereby amended by adding to the end
thereof:

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                  "Intercompany Loan by DSI to ADLT Realty in the amount of
                  $8,000 on or about July __, 2003"

         2.       REPRESENTATIONS, WARRANTIES AND COVENANTS. In addition to the
continuing representations, warranties and covenants heretofore or hereafter
made by Loan Parties to Agent and Lenders pursuant to the Loan Agreement and the
other Loan Documents, each Loan Party hereby represents, warrants and covenants
with and to Agent and Lenders as follows (which representations, warranties and
covenants are continuing and shall survive the execution and delivery hereof and
shall be incorporated into and made a part of the Loan Documents):

         (a)      No Event of Default exists on the date of this Amendment
(after giving effect to the amendments to the Loan Agreement set forth herein);
and

         (b)      This Amendment has been duly executed and delivered by each
Loan Party and is in full force and effect as of the date hereof, and the
agreements and obligations of each of the Loan Parties contained herein
constitute its legal, valid and binding obligations, enforceable against it in
accordance with the terms hereof.

         3.       EFFECT OF THIS AMENDMENT. Except as modified pursuant hereto,
no other changes or modifications to the Loan Agreement and the other Loan
Documents are intended or implied and in all other respects the Loan Agreement
and the other Loan Documents are hereby specifically ratified, acknowledged and
confirmed by all parties hereto as of the effective date hereof. To the extent
of any conflict between the terms of this Amendment and any of the Loan
Documents, the terms of this Amendment shall control. The Loan Agreement, as
amended hereby, the other Loan Documents and this Amendment shall be read and be
construed as one agreement.

         4.       FURTHER ASSURANCES. The parties hereto shall execute and
deliver such additional documents and take such additional actions as may be
necessary or desirable to effectuate the provisions and purposes of this
Amendment.

         5.       GOVERNING LAW. THE VALIDITY, INTERPRETATION AND ENFORCEMENT OF
THIS AMENDMENT AND ANY DISPUTE ARISING OUT OF THE RELATIONSHIP BETWEEN THE
PARTIES HERETO, WHETHER IN CONTRACT, TORT, EQUITY OR OTHERWISE, SHALL BE
GOVERNED BY THE INTERNAL LAWS OF THE STATE OF NEW YORK (WITHOUT GIVING EFFECT TO
PRINCIPLES OF CONFLICTS OF LAW).

         6.       BINDING EFFECT. This Amendment shall be binding upon and inure
to the benefit of each of the parties hereto and their respective successors and
assigns.

         7.       COUNTERPARTS. This Amendment may be executed in any number of
counterparts, but all of such counterparts when executed shall together
constitute but one and the same agreement. In making proof of this Amendment, it
shall not be necessary to produce or

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account for more than one counterpart thereof signed by each of the parties
hereto.

                                Very truly yours,

                                ADVANCED LIGHTING TECHNOLOGIES,
                                INC., an Ohio corporation, debtor and debtor-in-
                                possession, as a Borrower and a Loan Party

                                By: -s- Steven C. Potts
                                    -------------------------------------------

                                Name: Steven C. Potts
                                Title: CFO, Secretary & Treasurer

                                APL ENGINEERED MATERIALS, INC.,
                                an Illinois corporation, debtor and debtor-in-
                                possession, as a Borrower and a Loan Party

                                By: -s- Steven C. Potts
                                    -------------------------------------------

                                Name: Steven C. Potts
                                Title: CFO & Vice President

                                VENTURE LIGHTING INTERNATIONAL,
                                INC., an Ohio corporation, debtor and debtor-in-
                                possession, as a Borrower and a Loan Party

                                By: -s- Steven C. Potts
                                    -------------------------------------------

                                Name: Steven C. Potts
                                Title: CFO, Secretary & Treasurer

                                BALLASTRONIX (DELAWARE), INC.,
                                a Delaware corporation, debtor and debtor-in-
                                possession, as a Borrower and a Loan Party

                                By: -s- Steven C. Potts
                                    -------------------------------------------

                                Name: Steven C. Potts
                                Title: CFO, Secretary & Treasurer

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                                MICROSUN TECHNOLOGIES, INC.,
                                an Ohio corporation, debtor and debtor-in-
                                possession, as a Borrower and a Loan Party

                                By: -s- Steven C. Potts
                                    -------------------------------------------

                                Name: Steven C. Potts
                                Title: CFO, Secretary & Treasurer

                                LIGHTING RESOURCES INTERNATIONAL,
                                INC., an Ohio corporation, debtor and debtor-in-
                                possession, as a Borrower and a Loan Party

                                By: -s- Steven C. Potts
                                    -------------------------------------------

                                Name: Steven C. Potts
                                Title: CFO, Secretary & Treasurer

                                ADLT SERVICES, INC., an Ohio corporation,
                                debtor and debtor-in-possession, as a Borrower
                                and a Loan Party

                                By: -s- Steven C. Potts
                                    -------------------------------------------

                                Name: Steven C. Potts
                                Title: CFO, Secretary & Treasurer

                                VENTURE LIGHTING POWER SYSTEMS,
                                NORTH AMERICA INC., a Nova Scotia
                                corporation, as a Loan Party

                                By: -s- R.G. Douglas Oulton
                                    ------------------------------------------

                                Name: R.G. Douglas Oulton
                                Title: VP. Finance & Administration
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                                PARRY POWER SYSTEMS LIMITED,
                                a corporation organized under the laws of the
                                United Kingdom, as a Loan Party

                                By: -s- E. Young
                                    -------------------------------------------

                                Name: E. Young
                                Title: Director

                                VENTURE LIGHTING EUROPE LTD.,
                                a corporation organized under the laws of the
                                United Kingdom, as a Loan Party

                                By: -s- E. Young
                                    -------------------------------------------

                                Name: E. Young
                                Title: Director

                                DEPOSITION SCIENCES, INC.,
                                an Ohio corporation, as a Loan Party

                                By: -s- Steven C. Potts
                                    -------------------------------------------

                                Name: Steven C. Potts
                                Title: Treasurer

ACKNOWLEDGED AND AGREED:

WELLS FARGO FOOTHILL, INC.,
a California corporation, as Agent
and as a Lender

By: -s- John T. Leonard
    -------------------------------------

Name: John T. Leonard
Title: AVP

ABLECO FINANCE LLC, a Delaware
limited liability company, as a Lender

By: -s- Kevin Genda
    -------------------------------------

Name: Kevin Genda
Title: SVP