Exhibit 10.242

                                 EXHIBIT 10.242

NEITHER THIS WARRANT NOR THE SHARES ISSUABLE UPON EXERCISE HEREOF HAVE BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT")
OR ANY OTHER APPLICABLE SECURITIES LAWS IN RELIANCE UPON AN EXEMPTION FROM THE
REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND SUCH OTHER SECURITIES LAWS.
NEITHER THIS WARRANT NOR THE SHARES ISSUABLE UPON EXERCISE HEREOF MAY BE SOLD,
PLEDGED, TRANSFERRED, ENCUMBERED OR OTHERWISE DISPOSED OF EXCEPT PURSUANT TO AN
EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF IN A TRANSACTION
THAT IS EXEMPT FROM REGISTRATION UNDER THE PROVISIONS OF THE SECURITIES ACT.

                             STOCK PURCHASE WARRANT

                                   To Purchase
                          4,500 Shares of Common Stock
                                       of
                      Pollution Research and Control Corp.

     THIS CERTIFIES that, for value received, Christopher Mehringer (the
"Holder") is entitled, upon the terms and subject to the conditions hereinafter
set forth, at any time prior to the close of business on July 17, 2005 (the
"Termination Date"), but not thereafter, to subscribe for and purchase from
Pollution Research and Control Corp., a corporation incorporated in California
(the "Company"), up to Four Thousand Five Hundred (4,500) shares (the "Warrant
Shares") of the common stock, no par value, of the Company (the "Common Stock").
The purchase price of one share of Common Stock (the "Exercise Price") under
this Warrant shall be $2.2875. The Exercise Price and the number of shares for
which the Warrant is exercisable shall be subject to adjustment as provided
herein. Capitalized terms used and not otherwise defined herein shall have the
meanings set forth for such terms in the Securities Purchase Agreement dated as
of July 18, 2000 between the Company and the Holder. In the event of any
conflict between the terms of this Warrant and the Securities Purchase
Agreement, the Securities Purchase Agreement shall control.

           1. Title to Warrant. Prior to and subject to compliance with
applicable laws, this Warrant and all rights hereunder are transferable, in
whole or in part, at the office or agency of the Company by the Holder hereof in
person or by duly authorized attorney, upon surrender of this Warrant together
with the Assignment Form annexed hereto properly endorsed.

          2. Authorization of Shares. The Company covenants that all shares of
Common Stock that may be issued upon the exercise of rights represented by this
Warrant will, upon exercise of the rights represented by this Warrant, be duly
authorized, validly issued, fully paid and nonassessable and free from all
taxes, liens and charges in respect of the issue thereof (other than taxes in
respect of any transfer occurring contemporaneously with such issue).

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          3. Exercise of Warrant. Except as provided in Section 3(b) or Section
4 herein, exercise of the purchase rights represented by this Warrant may be
made at any time or times on or before the close of business on the Termination
Date by the surrender of this Warrant and the Notice of Exercise form annexed
hereto duly executed, at the office of the Company (or such other office or
agency of the Company as it may designate by notice in writing to the registered
Holder hereof at the address of such Holder appearing on the books of the
Company), and upon payment of the Exercise Price of the Warrant Shares thereby
purchased by wire transfer or cashier's check drawn on a United States bank. The
Holder of this Warrant shall be entitled to receive a certificate for the number
of shares of Common Stock so purchased. This Warrant may also be exercised in
whole or in part by means of a "cashless exercise" by means of tendering this
Warrant to the Company to receive the number of shares of Common Stock equal in
total Market Value (as hereinafter defined) to the difference between the total
Market Value of the shares of Common Stock issuable upon such exercise of this
Warrant and the total cash Exercise Price of that part of the Warrant being
exercised. "Market Value" for this purpose shall be the price for the last trade
of the Common Stock as reported by Bloomberg L.P. on the Trading Day of such
cashless exercise. Certificates for shares purchased hereunder shall be
delivered to the Holder hereof within three (3) Trading Days after the date on
which this Warrant shall have been exercised as aforesaid. This Warrant shall be
deemed to have been exercised and such certificate or certificates shall be
deemed to have been issued, and Holder or any other person so designated to be
named therein shall be deemed to have become a holder of record of such shares
for all purposes, as of the date the Warrant has been exercised by payment to
the Company of the Exercise Price and all taxes required to be paid by Holder,
if any, pursuant to Section 5 prior to the issuance of such shares, have been
paid. If this Warrant shall have been exercised in part, the Company shall, at
the time of delivery of the certificate or certificates representing Warrant
Shares, deliver to Holder a new Warrant evidencing the rights of Holder to
purchase the unpurchased shares of Common Stock called for by this Warrant;
which new Warrant shall in all other respects be identical with this Warrant.

          The Holder is granted all of the rights to registration with the
Securities and Exchange Commission and qualification in the states of the
Warrants Shares set forth in the Securities Purchase Agreement.

          4. No Fractional Shares of Scrip. No fractional shares or scrip
representing fractional shares shall be issued upon the exercise of this
Warrant. As to any fraction of a share that Holder would otherwise be entitled
to purchase upon such exercise, the Company shall pay a cash adjustment in
respect of such fraction of the Exercise Price based upon the Market Value on
the date of exercise.

          5. Charges, Taxes and Expenses. Issuance of certificates for shares of
Common Stock upon the exercise of this Warrant shall be made without charge to
the Holder hereof for any issue or transfer tax or other incidental expense in
respect of the issuance of such certificate, all of which taxes and expenses
shall be paid by the Company, and such certificates shall be issued in the name
of the Holder of this Warrant or in such name or names as may be directed by the
Holder of this Warrant; provided, however, that in the event certificates for
shares of Common Stock are to be issued in a name other than the name of the

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Holder of this Warrant, this Warrant when surrendered for exercise shall be
accompanied by the Assignment Form attached hereto duly executed by the Holder
hereof; and the Company may require, as a condition thereto, the payment of a
sum sufficient to reimburse it for any transfer tax incidental thereto.

          6. Closing of Books. The Company will not close its shareholder bo7oks
or records in any manner that prevents the timely exercise of this Warrant.

          7. Transfer, Division and Combination.

             (a) Subject to compliance with any applicable securities laws,
transfer of this Warrant and all rights hereunder, in whole or in part, shall be
registered on the books of the Company to be maintained for such purpose, upon
surrender of this Warrant at the principal office of the Company, together with
a written assignment of this Warrant substantially in the form attached hereto
duly executed by Holder or its agent or attorney, and payment of funds
sufficient to pay any transfer taxes payable upon the making of such transfer.
Upon such surrender and, if required, such payment, the Company shall execute
and deliver a new Warrant or Warrants in the name of the assignee or assignees
and in the denomination or denominations specified in such instrument of
assignment, and shall issue to the assignor a new Warrant evidencing the portion
of this Warrant not so assigned, and this Warrant shall promptly be cancelled. A
Warrant, if properly assigned, may be exercised by a new Holder for the purchase
of shares of Common Stock without having a new Warrant issued.

             (b) This Warrant may be divided or combined with other Warrants
upon presentation hereof at the aforesaid office of the Company, together with a
written notice specifying the names and denominations in which new Warrants are
to be issued, signed by Holder or its agent or attorney. Subject to compliance
with Section 7(a), as to any transfer that may be involved in such division or
combination, the Company shall execute and deliver a new Warrant or Warrants in
exchange for the Warrant or Warrants to be divided or combined in accordance
with such notice.

             (c) The Company shall prepare, issue and deliver at its own expense
(other than transfer taxes) the new Warrant or Warrants under this Section 7.

             (d) The Company agrees to maintain, at its aforesaid office, books
for the registration and the registration of transfer of the Warrants.

          8. No Rights as Shareholder until Exercise. This Warrant does not
entitle the Holder hereof to any voting rights or other rights as a shareholder
of the Company prior to the exercise hereof. Upon the surrender of this Warrant
and the payment of the aggregate Exercise Price, the Warrant Shares so purchased
shall be and be deemed to be issued to such Holder as the record owner of such
shares as of the close of business on the later of the date of such surrender or
payment.

          9. Loss, Theft, Destruction or Mutilation of Warrant. The Company
covenants that upon receipt by the Company of evidence reasonably satisfactory
to it of the loss, theft, destruction or mutilation of this Warrant certificate


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or any stock certificate relating to the Warrant Shares, and in case of loss,
theft or destruction, of indemnity or security reasonably satisfactory to it
(which shall not include the posting of any bond), and upon surrender and
cancellation of such Warrant or stock certificate, if mutilated, the Company
will make and deliver a new Warrant or stock certificate of like tenor and dated
as of such cancellation, in lieu of such Warrant or stock certificate.

          10. Saturdays, Sundays, Holidays, etc. If the last or appointed day
for the taking of any action or the expiration of any right required or granted
herein shall be a Saturday, Sunday or a legal holiday, then such action may be
taken or such right may be exercised on the next succeeding day not a Saturday,
Sunday or legal holiday.

          11. Adjustments of Exercise Price and Number of Warrant Shares.

              (a) Stock Splits, etc. The number and kind of securities
purchasable upon the exercise of this Warrant and the Exercise Price shall be
subject to adjustment from time to time upon the happening of any of the
following. In case the Company shall (i) pay a dividend in shares of Common
Stock or make a distribution in shares of Common Stock to holders of its
outstanding Common Stock, (ii) subdivide it outstanding shares of Common Stock
into a greater number of shares of Common Stock, (iii) combine its outstanding
shares of Common Stock into a smaller number of shares of Common Stock or (iv)
issue any shares of its capital stock in a reclassification of the Common Stock,
then the number of Warrant Shares purchasable upon exercise of this Warrant
immediately prior thereto shall be adjusted so that the Holder of this Warrant
shall be entitled to receive the kind and number of Warrant Shares or other
securities of the Company which he would have owned or have been entitled to
receive had such Warrant been exercised in advance thereof. Upon each such
adjustment of the kind and number of Warrant Shares or other securities of the
Company which are purchasable hereunder, the Holder of this Warrant shall
thereafter be entitled to purchase the number of Warrant Shares or other
securities resulting from such adjustment at an Exercise Price per Warrant Share
or other security obtained by multiplying the Exercise Price in effect
immediately prior to such adjustment by the number of Warrant Shares purchasable
pursuant hereto immediately prior to such adjustment and dividing by the number
of Warrant Shares or other securities of the Company resulting from such
adjustment. An adjustment made pursuant to this paragraph shall become effective
immediately after the effective date of such event retroactive to the record
date, if any, for such event.

              (b) Reorganization, Reclassification, Merger, Consolidation or
Disposition of Assets. In case the Company shall reorganize its capital,
reclassify its capital stock, consolidate or merge with or into another
corporation (where the Company is not the surviving corporation or where there
is a change in or distribution with respect to the Common Stock of the Company),
or sell, transfer or otherwise dispose of all or substantially all its property,
assets or business to another corporation and, pursuant to the terms of such
reorganization, reclassification, merger, consolidation or disposition of
assets, shares of common stock of the successor or acquiring corporation, or any
cash, shares of stock or other securities or property of any nature whatsoever
(including warrants or other subscription or purchase rights) in addition to or

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in lieu of common stock of the successor or acquiring corporation ("Other
Property"), are to be received by or distributed to the holders of Common Stock
of the Company, then Holder shall have the right thereafter to receive, upon
exercise of this Warrant, the number of shares of common stock of the successor
or acquiring corporation or of the Company, if it is the surviving corporation,
and Other Property receivable upon or as a result of such reorganization,
reclassification, merger, consolidation or disposition of assets by a holder of
the number of shares of Common Stock for which this Warrant is exercisable
immediately prior to such event. In case of any such reorganization,
reclassification, merger, consolidation or disposition of assets, the successor
or acquiring corporation (if other than the Company) shall expressly assume the
due and punctual observance and performance of each and every covenant and
condition of this Warrant to be performed and observed by the Company and all
the obligations and liabilities hereunder, subject to such modifications as may
be deemed appropriate (as determined in good faith by resolution of the Board of
Directors of the Company) in order to provide for adjustments of shares of
Common Stock for which this Warrant is exercisable which shall be as nearly
equivalent as practicable to the adjustments provided for in this Section 11.
For purposes of this Section 11, "common stock of the successor or acquiring
corporation" shall include stock of such corporation of any class which is not
preferred as to dividends or assets over any other class of stock of such
corporation and which is not subject to redemption and shall also include any
evidences of indebtedness, shares of stock or other securities which are
convertible into or exchangeable for any such stock, either immediately or upon
the arrival of a specified date or the happening of a specified event and any
warrants or other rights to subscribe for or purchase any such stock. The
foregoing provisions of this Section 11 shall similarly apply to successive
reorganizations, reclassifications, mergers, consolidations or disposition of
assets.

          12. Voluntary Adjustment by the Company. The Company may at any time
during the term of this Warrant, reduce the then current Exercise Price to any
amount and for any period of time deemed appropriate by the Board of Directors
of the Company.

          13. Notice of Adjustment. Whenever the number of Warrant Shares or
number or kind of securities or other property purchasable upon the exercise of
this Warrant or the Exercise Price is adjusted, as herein provided, the Company
shall promptly mail by registered or certified mail, return receipt requested,
to the Holder of this Warrant notice of such adjustment or adjustments setting
forth the number of Warrant Shares (and other securities or property)
purchasable upon the exercise of this Warrant and the Exercise Price of such
Warrant Shares (and other securities or property) after such adjustment, setting
forth a brief statement of the facts requiring such adjustment and setting forth
the computation by which such adjustment was made. Such notice, in the absence
of manifest error, shall be conclusive evidence of the correctness of such
adjustment.

          14. Notice of Corporate Action. If at any time:

              (i) the Company shall take a record of the holders of its Common
Stock for the purpose of entitling them to receive a dividend or other
distribution, or any right to subscribe for or purchase any evidences of its
indebtedness, any shares of stock of any class or any other securities or
property, or to receive any other right, or

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              (ii) there shall be any capital reorganization of the Company, any
reclassification or recapitalization of the capital stock of the Company or any
consolidation or merger of the Company with, or any sale, transfer or other
disposition of all or substantially all the property, assets or business of the
Company to, another corporation or,

              (iii) there shall be a voluntary or involuntary dissolution,
liquidation or winding up of the Company;

then, in any one or more of such cases, the Company shall give to Holder (i) at
least 30 days' prior written notice of the date on which a record date shall be
selected for such dividend, distribution or right or for determining rights to
vote in respect of any such reorganization, reclassification, merger,
consolidation, sale, transfer, disposition, liquidation or winding up, and (ii)
in the case of any such reorganization, reclassification, merger, consolidation,
sale, transfer, disposition, dissolution, liquidation or winding up, at least 30
days' prior written notice of the date when the same shall take place. Such
notice in accordance with the foregoing clause also shall specify (i) the date
on which any such record is to be taken for the purpose of such dividend,
distribution or right, the date on which the holders of Common Stock shall be
entitled to any such dividend, distribution or right, and the amount and
character thereof, and (ii) the date on which any such reorganization,
reclassification, merger, consolidation, sale, transfer, disposition,
dissolution, liquidation or winding up is to take place and the time, if any
such time is to be fixed, as of which the holders of Common Stock shall be
entitled to exchange their shares of Common Stock for securities or other
property deliverable upon such disposition, dissolution, liquidation or winding
up. Each such written notice shall be sufficiently given if addressed to Holder
at the last address of Holder appearing on the books of the Company and
delivered in accordance with Section 16(d).

          15. Authorized Shares.

              (a) The Company covenants that during the period the Warrant is
outstanding, it will reserve from its authorized an unissued Common Stock a
sufficient number of shares to provide for the issuance of the Warrant Shares
upon the exercise of any purchase rights under this Warrant. The Company further
covenants that its issuance of this Warrant shall constitute full authority to
its officers who are charged with the duty of executing stock certificates to
execute and issue the necessary certificates for the Warrant Shares upon the
exercise of the purchase rights under this Warrant. The Company will take all
such reasonable action as may be necessary to assure that such Warrant Shares
may be issued as provided herein without violation of any applicable law or
regulation, or of any requirements of the Principal Market upon which the Common
Stock may be listed.

              (b) The Company shall not by any action, including, without
limitation, amending its certificate of incorporation or through any
reorganization, transfer of assets, consolidation, merger, dissolution, issue or
sale of securities or any other voluntary action, avoid or seek to avoid the

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observance or performance of any of the terms of this Warrant, but will at all
times in good faith assist in the carrying out of all such terms and in the
taking of all such actions as may be necessary or appropriate to protect the
rights of Holder against impairment. Without limiting the generality of the
foregoing, the Company will (i) not increase the par value of any shares of
Common Stock receivable upon the exercise of this Warrant above the amount
payable therefor upon such exercise immediately prior to such increase in par
value, (ii) take all such action as may be necessary or appropriate in order
that the Company may validly and legally issue fully paid and nonassessable
shares of Common Stock upon the exercise of this Warrant, and (iii) use its best
efforts to obtain all such authorizations, exemptions or consents from any
public regulatory body having jurisdiction thereof as may be necessary to enable
the Company to perform its obligations under this Warrant.

              (c) Upon the request of Holder, the Company will at any time
during the period this Warrant is outstanding acknowledge in writing, in form
reasonably satisfactory to Holder, the continuing validity of this Warrant and
the obligations of the Company hereunder.

              (d) Before taking any action pursuant to Section 11 or 12 that
would cause an adjustment reducing the current Exercise Price below the then par
value, if any, of the shares of Common Stock issuable upon exercise of the
Warrants, the Company shall take any corporate action that may be necessary in
order that the Company may validly and legally issue fully-paid and
nonassessable shares of such Common Stock at such adjusted Exercise Price.

              (e) Before taking any action that would result in an adjustment in
the Exercise Price, the Company shall obtain all such authorizations or
exemptions thereof, or consents thereto, as may be necessary from any public
regulatory body or bodies having jurisdiction thereof.

          16. Miscellaneous.

              (a) Jurisdiction. This Warrant shall be binding upon any
successors or assigns of the Company. This Warrant shall constitute a contract
under the laws of New York without regard to its conflict of law principles or
rules, and be subject to arbitration pursuant to the terms set forth in the
Securities Purchase Agreement.

              (b) Restrictions. The Holder hereof acknowledges that the Warrant
Shares acquired upon the exercise of this Warrant, if not registered, will have
restrictions upon resale imposed by state and Federal securities laws.

              (c) Nonwaiver and Expenses.No course of dealing or any delay or
failure to exercise any right hereunder on the part of Holder shall operate as a
waiver of such right or otherwise prejudice Holder's rights, powers or remedies;
notwithstanding which all rights hereunder terminate on the Termination Date. If
the Company fails to comply with any provision of this Warrant, the Company
shall pay to Holder such amounts as shall be sufficient to cover any costs and
expenses including, but not limited to, reasonable attorneys' fees, including
those of appellate proceedings, incurred by Holder in collecting any amounts due
pursuant hereto or in otherwise enforcing any of its rights, powers or remedies
hereunder.

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              (d) Notices.Any notice, request or other document required or
permitted to be given or delivered to the Holder hereof by the Company shall be
delivered in accordance with the notice provisions of the Securities Purchase
Agreement.

              (e) Limitation of Liability.No provision hereof, in the absence of
affirmative action by Holder to purchase shares of Common Stock, and no
enumeration herein of the rights or privileges of Holder hereof, shall give rise
to any liability of Holder for the purchase price of any Common Stock or as a
stockholder of the Company, whether such liability is asserted by the Company or
by creditors of the Company.

              (f) Remedies. Holder, in addition to being entitled to exercise
all rights granted by law, including recovery of damages, will be entitled to
specific performance of its rights under this Warrant. The Company agrees that
monetary damages would not be adequate compensation for any loss incurred by
reason of a breach by it of the provisions of this Warrant and hereby agrees to
waive the defense in any action for specific performance that a remedy at law
would be adequate.

              (g) Successors and Assigns.Subject to applicable securities laws,
this Warrant and the rights and obligations evidenced hereby shall inure to the
benefit of and be binding upon the successors of the Company and the successors
and permitted assigns of Holder. The provisions of this Warrant are intended to
be for the benefit of all Holders from time to time of this Warrant and shall be
enforceable by any such Holder or holder of Warrant Shares.

              (h) Indemnification.The Company agrees to indemnify and hold
harmless Holder from and against any liabilities, obligations, losses, damages,
penalties, actions, judgments, suits, claims, costs, attorneys' fees, expenses
and disbursements of any king that may be imposed upon, incurred by or asserted
against Holder in any manner relating to or arising out of any failure by the
Company to perform or observe in any material respect any of its covenants,
agreements, undertakings or obligations set forth in this Warrant; provided,
however, that the Company will not be liable hereunder to the extent that any
liabilities, obligations, losses, damages, penalties, actions, judgments, suits,
claims, costs, attorneys' fees, expenses or disbursements are found in a final
non-appealable judgment by a court to have resulted from Holder's negligence,
bad faith or willful misconduct in its capacity as a stockholder or
warrantholder of the Company.

              (i) Severability. Wherever possible, each provision of this
Warrant shall be interpreted in such manner as to be effective and valid under
applicable law, but if any provision of this Warrant shall be prohibited by or
invalid under applicable law, such provision shall be ineffective to the extent
of such prohibition or invalidity, without invalidating the remainder of such
provisions or the remaining provisions of this Warrant.

              (k) Headings. The headings used in this Warrant are for the
convenience of reference only and shall not, for any purpose, be deemed a part
of this Warrant.

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     IN WITNESS WHEREOF, the Company has caused this Warrant to be executed by
its officer thereunto duly authorized.


Dated:  July 17, 2000                       POLLUTION RESEARCH AND CONTROL CORP.


                                            By:  /s/  Albert E. Gosselin, Jr.
                                               --------------------------------
                                                      Albert E. Gosselin, Jr.
                                                      President

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                               NOTICE OF EXERCISE


To:      Pollution Research and Control Corp.

                  (1) The  Undersigned  hereby elects to purchase  _____________
shares of Common  Stock (the "Common  Stock") of Pollution  Research and Control
Corp.,  pursuant to the terms of the attached Warrant,  and [ ] tenders herewith
payment of the  exercise  price in full OR [ ] tenders the Warrant for  cashless
exercise, together with all applicable transfer taxes, if any.

     (2) Calculation of cashless exercise value, if applicable:
________________________________________________________________________________
_____________________________________________________________________.

                  (3) Please issue a certificate  or  certificates  representing
said shares of Common Stock in the name of the undersigned or in such other name
as is specified below:

                                    _________________________________
                                    (Name)

                                    _________________________________
                                    (Address)

                                    _________________________________


Dated:  ______________


                                            __________________________________
                                            Signature


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                                 ASSIGNMENT FORM

                    (To assign the foregoing Warrant, execute
                   this form and supply required information.
                 Do not use this form to exercise the Warrant.)


     FOR VALUE RECEIVED, the foregoing Warrant and all rights evidenced thereby
are hereby assigned to:

_________________________________________________ whose address is:

_________________________________________________

_________________________________________________

                                            Dated: _________________

                                       Holder's Signature:______________________

                                       Holder's Address:________________________

                                                        ________________________


Signature Guaranteed:  _____________________________________________


NOTE: The signature to this Assignment Form must correspond with the name as it
appears on the face of the Warrant, without alteration or enlargement or any
change whatsoever, and must be guaranteed by a bank or trust company. Officers
of corporations and those acting in a fiduciary or other representative capacity
should file proper evidence of authority to assign the foregoing Warrant.

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