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                                 EXHIBIT 10.6

                                  CREDIT SALE

STATE OF LOUISIANA

PARISH OF PLAQUEMINES


          BE IT KNOWN, that on this 3RD day of DECEMBER, 1996;

          BEFORE ME, GEORGE, PIVACH, II, a Notary Public duly commissioned and
qualified in and for the Parish of Plaquemines, State of Louisiana, in the
presence of the undersighed competent witnesses;

          PERSONALLY CAME AND APPEARED:

          HUGH F. O'CONNOR, SR.,
          a person of the full age of majority and resident of the Parish of
          Jefferson, State of Louisiana, who declared unto me, Notary, that he
          has been married once and then Elaine Wichers O'Connor who predeceased
          him, and he has not since remarried; (HIS SS####-##-####)

          whose mailing address is 1121 NEWTON STREET, GRETNA, LOUISIANA
          70053;

hereinafter called Vendor(s) who declare(s) that he (they) does (do) by these
presents, grant, bargain, sell, convey, transfer, assign, set over, abandon and
deliver, with all legal warranties and with full substitution ain and to all the
rights and actions of warranty which Vendor(s) has (have) or may have against
all preceding owners and vendors, unto Purchaser(s),

          LABORATORY SPECIALISTS, INC.,
          a Louisiana Corporation, herein represented by its duly authorized
          representative, pursuant to Resolution of the Board of Directors,
          dated December 3, 1996, an original (ID #72-0846066)

whose mailing address is: 113 Jarrell Street, Belle Chasse, Louisiana 70037;

here present accepting and purchasing for itself, its heirs and assigns, and
acknowledging due delivery and possession thereof, all and singular the
following described property, to-wit:

I.
A CERTAIN LOT OF GROUND, together with all of the buildings and improvements
thereon, and all of the rights, ways, privileges, servitudes, appurtenances and
advantages thereunto belonging or in anywise appertaining, situated in the City
of Gretna, Parish of Jefferson, State of Louisiana, in square bounded by
Eleventh and Thirteenth Streets, Newton Street and the line of the Village of
Gretna, designated as Lot A-2 on a plan of survey made by Hotard & Webb, C.E.,
dated January 20, 1955 in Gretna, Louisiana, approved by resolution of the Mayor
and board of Alderman of the City of Gretna, adopted February 1, 1955, copies of
which survey and resolution are attached to act of sale passed before Frederick
J.R. Heebe, Notary Public, dated February 9, 1955, being a sale from Ruth Ziifle
to Harold R. Ziifle, et al, and recorded in COB 373, folio 177, Parish of
Jefferson, Louisiana, said Lot A-2 being part of Lot A on a plan of survey made
Hotard & Webb, C.E., dated Gretna, Louisiana, May 7, 1948, and revised May 19,
1948, a copy of which said plan is attached to act of sale by William C. Ziifle
to Mrs. Leonora Ziifle Geiger by act before William J.

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White, Notary Public, dated July 2, 1949, registered in COB 274, folio 216,
Jefferson Parish; said Lot A-2 measures 172. 32 feet front on Newton Street, one
hundred sixty-nine and 96/100 feet width in the rear along the line of the
Village of Gretna, by a depth on the line separating Lot A-2 from A-1 of 126.75
feet, by a depth and front on Eleventh Street of 125.84 feet.

Being the same property acquired by O'Connor Enterprises, Inc. from Ruth C.
Ziifle, by act passed before Nat B. Knight, Jr., Notary Public, dated April 20,
1956, registered in COB 400, folio 554, Jefferson Parish, Louisiana.

Being further acquired by Elaine Wichers, wife of/and Hugh F. O'Connor from
O'Connor Enterprises, Inc. by act before Henry J. Berthelot, N.P., dated
September 29, 1982, registered in COB __________ , folio __________ .

II.
A CERTAIN PORTION OF GROUND, together with all of the buildings and improvements
thereon, and all of the rights, ways, privileges, servitudes, appurtenances and
advantages thereunto belonging or in anywise appertaining, situated in the rear
of the Village of Mechanickham, now a part of the City of Gretna, Parish of
Jefferson, State of Louisiana, designated as Parts of Lots Two (2) and Three (3)
of Square One (1), as per sketch annexed to sale by C.D. Vicknair to M.
Schneider, passed before S.J. McCune, Notary Public, for this Parish, December
23, 1919; said portion of land measures Thirty-eight (38') feet front on
continuation of line of Newton Street, by One hundred thirty-one (131') feet
depth and Thirty-six (36') feet width on rear, the dividing line of property now
or formerly belonging to E.L. Slattery. The tract of land of which the above
forms part designated by the Letter "B", on sketch made by H.L. Zander, Parish
Engineer, on April 17, 1909, annexed to act of partition, between Mary Vicknair
and W.C. Ziifle, before John E. Fleury, Notary Public, for this Parish, on April
24, 1909.

Being the same property acquired by O'Connor Enterprises, Inc. from Jeannette
Louise Vicknair, Gladys Davies and Joseph J. Davies, Jr. by act before John
D'Angelo, Notary Public dated June 9, 1966, registered in COB 638, folio '22,
Parish of Jefferson, Louisiana.

Being further acquired by Elaine Wichers, wife of/and Hugh O'Connor from
O'Connor Enterprises, Inc. by act befor Henry J. Berthelot, N.P., dated
September 29, 1982, registered in COB __________ , folio __________ .

III.
A CERTAIN PIECE OF PORTION OF GROUND, together with all of the buildings and
improvements thereon, and all of the rights, ways, privileges, servitudes,
appurtenances and advantages thereunto belonging or in anywise appertaining,
designated as Lot 4 of Block 1 of Vicknair Subdivision, located in the City of
Gretna, Parish of Jefferson, State of Louisiana, all as per sketch attached to
an act passed before S.J. McCune, Notary Public, dated December 23, 1919, and
which portion of ground measures 7 feet front on a continuation of Newton
Street, a width across the rear of 6 feet inches, more or less, and a depth of
131 feet between equal lines.

Being the same property acquired by O'Connor Enterprises, Inc. from Cleo Gahn
Smith, by act before Robert B. Evans, Jr., Notary Public, dated September 4,
1980, recorded in COB 988, folio 277, Jefferson Parish, Louisiana.

Being further acquired by Elaine Wichers, wife of/and Hugh O'Connor from
O'Connor Enterprises, Inc. by act before Henry J. Berthelot, N.P., dated
September 29, 1982, registered in COB __________ , folio __________ .

IV.
A CERTAIN LOT OF GROUND, together with all of the buildings and improvements
thereon, and all of the rights, ways, privileges, servitudes, appurtenances and
advantages thereunto belonging or in anywise appertaining, situated in the rear
of the Village of Mechanickham, now a forming part of the City of Gretna, Parish
of Jefferson, State of Louisiana, designated as Lot Five (5) of Block One (1) of
Vicknair Subdivision, as per sketch attached to and made part of an act before
Samuel James McCune on the 23rd day of November, 1919, being a sale of Property
by Charles

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Didier Vicknair to Michel Schneider; said lot begins at a distance of one
hundred twenty-four (124') feet on the front line from Eleventh street and a
distance of one hundred sixteen (116') feet on the rear line from said Eleventh
Street separating it from property now or formerly belonging to Edward L.
Slattery and thence measures thirty-four (34') feet front on the continuation of
Newton Street, twenty-nine (29') feet in width on the rear line dividing it from
the said Slattery property by a depth of one hundred thirty-one (131') feet, all
as per sketch herein referred to.

Being the same property acquired by Elaine Wichers, wife of/and Hugh F.
O'Connor, Sr. by act before William J. Scheffler, III, Notary Public, dated
March 15, 1984, registered in COB 1070, folio 226, and further acquired by
Boundary Agreement and Recognition of Title, by act dated September 7, 1984
before Michael E. Nolan, Notary Public, registered in COB 1096, folio 237, on
September 10, 1984.

TRACTS II, III AND IV MAY ALSO BE DESCRIBED COLLECTIVELY AS FOLLOWS TO WIT:

THAT CERTAIN PIECE OR PORTION OF GROUND, together with all of the buildings and
improvements thereon, and all of the rights, ways, privileges, servitudes,
appurtenances and advantages thereunto belonging or in anywise appertaining,
situtated in the PARISH OF JEFFERSON, CITY OF GRETNA, in that part thereof known
as the VICKNAIR ADDITION, as more fully shown on a plan of survey by Wilton J.
Dufrene, dated May 30, 1984, according to which said portion of ground commences
48.09 feet from the intersection of 11th Street and Newton Street and measures
thence 115 feet front on Newton Street, a width in the rear of 105.59 feet, by a
depth on the side line nearer to the Westbank Expressway of 126.22 feet and on
the opposite side line of 125.98 feet.

Being the same property acquired by Elaine Wichers, wife of /and Hugh F.
O'Connor, Sr. by act before William J. Scheffler, III, Notary Public, dated
March 15, 1984, registered in COB 1070, folio 226, and further acquired by
Boundary Agreement and Recognition of Title, by act dated September 7, 1984,
before Michael E. Nolan, Notary Public, registered in COB 1096, folio 237, on
September 10, 1984.

Further acquired by Hugh O'Connor, Sr. by Judgment of Possession through the
Succession of Elaine Wichers, Proceedings No. 499-389 of the 24th Judicial
District Court for the Parish of Jefferson, State of Louisiana, registered in
COB 2951, Folio 339 of the records of the Parish of Jefferson, State of
Louisiana.

All as more fully shown on survey by Dufrene Surveying & Engineering, Inc.,
dated December ___ , 1996, a copy of which is attached hereto and made a part
hereof.

     This sale is made and accepted for and in consideration of the price and
sum of FOUR HUNDRED FIFTY THOUSAND AND NO/100 ($450,000.00) DOLLARS, in part
payment and deduction whereof the said Purchaser(s) have well and truly paid, in
CASH, the sum of ZERO DOLLARS AND NO/100 ($0.00) DOLLARS, to the Vendor(s), who
hereby acknowledge receipt thereof and grant(s) full acquittance and discharge
therefor. And for the balance of said purchase price, the sum of FOUR HUNDRED
FIFTY THOUSAND AND NO/100 ($450,000.00) DOLLARS, the Purchaser(s) has (have)
furnished Vendor(s) ONE promissory note for the sum of FOUR HUNDRED FIFTY
THOUSAND AND NO/100 ($450,000.00) DOLLARS, dated this day, payable to the order
of HUGH O'CONNOR, SR., the principal sum of FOUR HUNDRED FIFTY THOUSAND AND
NO/100 ($450,000.00) DOLLARS, with interest from date hereof until paid at the
rate of ZERO (0.00%) percent per annum, payable ON DEMAND ONE HUNDRED EIGHTY
(180) DAYS FROM DATE, which said Note was parphed "Ne Varietur" by me, Notary
for identification herewith, and the Vendor(s) acknowledge(s) its receipt and
accepts this mortgage.

     In order to secure the full payment of this indebtedness in principal and
interest, together with all costs, including attorney's fees of 25.000% per cent
of the amount due or in suit, if it should be placed in the hands of an attorney
for collection, by suit or otherwise, Purchaser(s) specially mortgage(s) unto
Vendor(s) and such person or persons who may eventually be the holder or holders
of the note, the herein described property.

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     The property shall remain mortgaged and hypothecated until the full and
final payment of the note. Purchaser(s) shall not sell, transfer or alienate the
mortgaged property without the prior written consent of the Vendor(s). The
failure to obtain the Vendor's prior written consent shall be a condition of
default that shall, at the option of Vendor(s) accelerate all the obligations
secured by this mortgage. If the Vendor(s) agree(s) to accept or permit an
assumption of this mortgage, and the obligations it secures, by a third party,
the Vendor(s), at its sole discretion, may increase the interest rate and charge
transfer or other fees in such amounts as it may see fit. In such an event, the
Purchaser(s) shall not be released from any obligation imposed by this mortgage
or from any obligations this mortgage secures. The property shall not be sold,
alienated, or encumbered to the Vendor(s) prejudice. If the debt, or any part of
it, is not punctually paid at its maturity, and according to its tenor, it shall
be lawful for the property mortgaged to be seized and sold under executory
process issued by any court of competent jurisdiction, without appraisement, to
the highest bidder, payable cash; Purchaser(s) hereby expressly confess judgment
in favor of any holder of the note, for its full amount with interest, and
costs, including attorney's fees and all other amounts secured hereby.
Purchaser(s) further expressly waives citation and alll notices and delays,
including the three-day notice provided by Article 2639 of the Code of civil
Procedure.

     Purchaser(s) shall pay all taxes assessed and all liens which may be
asserted by any governmental authorities against the property before they become
delinquent, and keep the buildings and improvements on it, or which may be
placed on it, constantly isured against loss by fire, flood, wind, storm and
such other casualties as are covered by the Louisiana standard insurance
extended coverage form in an amount equal to the unpaid balance of the note
unless otherwise noted herein, in slovent insurance companies, and shall deliver
the policies and renewal of such insurance to the holder of the note. If
Purchaser(s) fails to do so, the holder is authorized (but not obligated) to pay
the taxes or liens, and cause such insurance to be effected, at Purchaser(s)
expense. The holder of said note shall become subrogated to all the rights and
privileges of the governmental authorities to which taxes or liens were due, and
all sums expended in paying taxes, liens, fees or insurance shall bear interest
at the rate of ten (10%) percent per annum from date of disbursement, and be
further secured by this mortgage to the additional amount of twenty (20%)
percent of the original amount of the note.

     If Purchaser(s) shall become insolvent, or apply to a bankruptcy court to
be adjudged a voluntary bankrupt, or proceedings be instituted to have
Purchaser(s) adjudged an involuntary bankrupt, or proceedings be taken against
Purchaser(s) looking to the appointment of a receiver or syndic, or any
proceedings be instituted for the seizure or sale of the property herein
mortgaged by judicial process, or in case Purchaser(s) should fail to pay the
note, any sum secured by this mortgage, or any part thereof, or the interest
thereon, or the taxes, promptly when due, or to effect and keep in force
insurance, or to transfer and deliver the policies as herein provided, or sell,
transfer or alienate the herein described property without the consent of
Mortgagee, then in any such event, at the option of the holder of the note, all
the indebtedness shall ipso facto, and without any demand or putting in default,
become immediatedly due and exigible. Failure on the part of the holder of the
note to insist on strict compliance of the terms of this mortgage or delays on
the part of the holder of the note in exercising any rights herein shall not
operate as a waiver thereof.

     All parties signing the within instrument have declared themselves to be of
full legal capacity.

     Both the Purchaser and Purchaser's spouse declare that they do expressly
waive and renounce in favor of the holder of the note any homestead exemption or
claim thereto, under the Constitution and laws of this State with respect to the
property being mortgaged. The word "NOTE" as used above includes the several
notes, if more than one is referred to, and that term includes all indebtedness
secured hereby, including principal, interest, attorney's fees and costs.

     All agreements and stipulations herein contained, and all the obligations
herein assumed, shall inure to the benefit of and be binding upon the heirs,
successors and assigns of the respective parties hereto.

     The singular herein shall include the plural and the masculine gender shall
include the feminine and neuter genders, and vice versa.

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     Parish and/or City taxes up to and including 1995 are paid as per
certificate annexed. The taxes are assumed by the Purchaser(s).

     By reference to the Mortgage Conveyance and Paving (if applicable)
Certificates annexed hereto it does not appear that said property has been
heretofore alienated by the Vendor(s) or that it is subject to any encumbrances
whatever, except those inscribed thereon which are accepted and/or assumed by
the Purchase(s) or will be canceled by me, Notary.

     The parties to this Act are aware that the Mortgage, Conveyance and Paving
(if applicable) Certificates herein referred to are open and not yet dated and
signed, and relieve and release me, Notary, from all responsibility by reason
thereof.

     The parties hereto requested that a environmental site assessment of the
property described herein not be made and none ws made and hereby relieve and
release me, Notary, from any and all responsibility in connection therewith and
further acknowledge that I, Notary, have advised them of the risks in failing to
obtain said assessment.

     THUS DONE AND PASSED on the day, month and year herein first above written,
in the presence of the undersigned competent witnesses, who hereto sign their
names with the said appearers and me, Notary, after reading of the whole.


WITNESSES                         LABORATORY SPECIALISTS, INC.

                                  /s/ ARTHUR R. PETERSON, JR.
                                          BY: ARTHUR R. PETERSON, JR.

/s/ HUGH F. O'CONNOR, JR.         /s/ HUGH F. O'CONNOR, SR.
                                          HUGH F. O'CONNOR, SR.



                          ---------------------------
                                 NOTARY PUBLIC

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