1
- --------------------------------------------------------------------------------

     As filed with the Securities and Exchange Commission on July 14, 1999

                       SECURITIES AND EXCHANGE COMMISSION
                                Washington, D.C.

                            -------------------------

                                    FORM S-3
                             Registration Statement
                                    Under The
                             Securities Act of 1933

                            ------------------------
                           INTERNATIONAL ISOTOPES INC.
                 (Name of Small Business Issuer in its Charter)


                                                                          
            TEXAS                                   2835                            74-276837
  (State or other Jurisdiction           (Primary Standard Industrial            (I.R.S. Employer
of Incorporation or Organization)        Classification Code Number)            Identification No.)


                             3100 JIM CHRISTAL ROAD
                            Denton, Texas 76207-9987
                                 (940) 484-9492
          (Address and Telephone Number of Principal Executive Offices
                        and Principal Place of Business)

                            IRA LON MORGAN, CHAIRMAN
                             3100 JIM CHRISTAL ROAD
                            Denton, Texas 76207-9987
                                 (940) 484-9492
            (Name, Address and Telephone Number of Agent for Service)

                                    COPY TO:
                                CURTIS R. ASHMOS
                            LOCKE LIDDELL & SAPP LLP
                             100 CONGRESS, SUITE 300
                               AUSTIN, TEXAS 78701
                                 (512) 305-4716
                APPROXIMATE DATE OF PROPOSED SALE TO THE PUBLIC:
     From time to time after this Registration Statement becomes effective.

         If the only securities being registered on this form are being offered
pursuant to dividend or interest reinvestment plans, check the following box.
[ ]

         If any of the securities being registered on this form are to be
offered on a delayed or continuous basis pursuant to Rule 415 under the
Securities Act of 1933, check the following box. [X]

         If this form is filed to register additional securities for an offering
pursuant to Rule 462(b) under the Securities Act, please check the following box
and list the Securities Act registration statement number of the earlier
effective registration statement for the same offering. [ ]

         If this form is a post-effective amendment filed pursuant to Rule
462(c) under the Securities Act, check the following box and list the Securities
Act registration statement number of the earlier effective registration
statement for the same offering. [ ]

         If delivery of the prospectus is expected to be made pursuant to Rule
434, please check the following box. [ ]



- ----------------------- -------------------- --------------------- --------------------- --------------------
                                               PROPOSED MAXIMUM      PROPOSED MAXIMUM
 TITLE OF EACH CLASS       AMOUNT TO BE       OFFERING PRICE PER    AGGREGATE OFFERING        AMOUNT OF
 OF SECURITIES TO BE        REGISTERED              SHARE                 PRICE           REGISTRATION FEE
      REGISTERED
- ----------------------- -------------------- --------------------- --------------------- --------------------
                                                                             
Common Stock, $.01      1,503,804 shares         $9.03125 (1)        $13,581,230 (1)        $3,775.58
par value
- ----------------------- -------------------- --------------------- --------------------- --------------------


         (1) Estimated in accordance with Rule 457(c) of the Securities Act of
1933 solely for the purpose of calculating the registration fee based upon an
assumed price of $9.03125, the average of the high and low sales prices of the
Common Stock as reported on Nasdaq SmallCap Market on July 12, 1999.

         THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE
OR DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT
SHALL FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS

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REGISTRATION STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH
SECTION 8(a) OF THE SECURITIES ACT OF 1933 OR UNTIL THE REGISTRATION STATEMENT
SHALL BECOME EFFECTIVE ON SUCH DATE AS THE COMMISSION, ACTING PURSUANT TO SAID
SECTION 8(a), MAY DETERMINE.


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PROSPECTUS

                                1,503,804 SHARES

                           INTERNATIONAL ISOTOPES INC.
                                  COMMON STOCK

                            -------------------------

         This Prospectus relates to the offering for resale of 1,503,804 shares
of Common Stock, par value $.01 per share (the "Common Stock"), of International
Isotopes Inc. ("I(3)" or the "Company"). All of the Common Stock being
registered may be offered and sold from time to time by certain selling
stockholders of the Company. See "Selling Stockholders" and "Plan of
Distribution." The Company will not receive any proceeds from the sale of the
Common Stock by the Selling Stockholders.

         The Company's Common Stock is quoted on the Nasdaq SmallCap Market
under the symbol "INIS" and is listed on the Boston Stock Exchange ("BSE") under
the symbol "ITL." On July 12, 1999, the last reported sale price for the
Company's Common Stock on the Nasdaq SmallCap Market was $9.1875 per share.

                       -----------------------------------

                      THE SECURITIES OFFERED HEREBY INVOLVE
                        A HIGH DEGREE OF RISK. SEE "RISK
                               FACTORS" ON PAGE 1.

                       -----------------------------------

                       NEITHER THE SECURITIES AND EXCHANGE
           COMMISSION NOR ANY STATE SECURITIES COMMISSION HAS APPROVED
              OR DISAPPROVED THESE SECURITIES OR DETERMINED IF THIS
                     PROSPECTUS IS TRUTHFUL OR COMPLETE. ANY
                        REPRESENTATION TO THE CONTRARY IS
                               A CRIMINAL OFFENSE.

                       -----------------------------------

         The Company has not authorized any person, agent or entity to give any
information or make any representation other than those contained in this
Prospectus (including material incorporated by reference herein). You should not
rely on any such information or representation as having been authorized by the
Company. This Prospectus is not an offer to sell the securities and it is not
soliciting an offer to buy the securities in any state where offers or sales are
not permitted.

                  The date of this Prospectus is July 13, 1999


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                                TABLE OF CONTENTS



                                                                        
Forward Looking Statements..................................................1

The Company.................................................................1

Risk Factors................................................................1

Selling Stockholders........................................................2

Plan of Distribution........................................................3

Incorporation of Certain Documents by Reference.............................4

Legal Matters...............................................................6

Experts.....................................................................6

Available Information.......................................................6




   5



                           FORWARD-LOOKING STATEMENTS

         This Prospectus contains, or incorporates by reference, certain
statements that may be deemed "forward-looking statements" within the meaning of
Section 27A of the Securities Act and Section 21E of the Exchange Act. All
statements, other than statements of historical facts, that address activities,
events or developments that the Company intends, expects, projects, believes or
anticipates will or may occur in the future are forward-looking statements. Such
statements are based on experience, market trends, our perception of historical
trends, current conditions, expected future developments and other factors
believed to be appropriate. The forward-looking statements included in this
Prospectus are also subject to a number of material risks and uncertainties,
including but not limited to economic, competitive, market, governmental and
technological factors affecting the Company's operations, production, markets,
products, services and prices, and other factors discussed in our filings under
the Securities Act and the Exchange Act. Investors are cautioned that such
forward-looking statements are not guarantees of our future performance and that
actual results, developments and business decisions may differ from those
envisioned by our forward-looking statements.

                                   THE COMPANY

         International Isotopes Inc., a Texas corporation (the "Company," "We"
or "I(3)"), is a developmental stage Company that has begun executing plans for
operations in the production, marketing, and distribution of a full range of
products used in diagnostic and therapeutic nuclear medicine, research and
industry. Completion of the plans we have developed will establish the first
independent commercial domestic producer of a full range of finished
radiopharmaceuticals (on a contract or joint venture basis), pharmaceutical
grade radioisotopes, radioisotopes and medical devices for commercial sale to
the nuclear medicine industry for the diagnosis and therapeutic treatment of
cancer and other diseases. We are also engineering instrumentation and products
for the radiation therapy and medical imaging markets.

         Our principal executive offices located at 3100 Jim Christal Road,
Denton, Texas 76207-9987. The telephone number is (940) 484-9492.

                                  RISK FACTORS

         An investment in our Common Stock is speculative and involves a
substantial degree of risk. Investors should carefully consider, along with
other information in this Prospectus, the considerations and risks set forth in
the Company's Annual Report on Form 10-K for the year ended December 31, 1998
and other reports and documents filed by the Company from time to time with the
SEC in evaluating an investment in our Company. You should not purchase any
Common Stock unless you can afford to lose your entire investment.

   6


                              SELLING STOCKHOLDERS

The following table sets forth certain information, as of June 30, 1999, with
respect to the shares of Common Stock beneficially owned prior to the offering
and the shares being offered hereby by the stockholders listed below (the
"Selling Stockholders"). All of the shares of Common Stock offered hereby
underly other securities issued originally in a transaction not involving a
public offering. Absent the current registration, such shares may not be sold by
the Selling Stockholders, except in certain limited situations including
compliance with Rule 144 under the Securities Act.

         The Selling Stockholders on May 18, 1999 acquired in a private
placement $10,000,000 of the Company's 5% Convertible Redeemable Preferred Stock
and Warrants to purchase up to 410,000 shares of the Company's Common Stock. The
shares offered hereby represent shares of Common Stock issuable to the Selling
Stockholders as a result of (i) conversion of the Preferred Stock (ii) payment
of interest on the Preferred Stock (in lieu of cash) and (iii) exercise of the
Warrants.



                                  SHARES OF COMMON STOCK
                                 BENEFICIALLY OWNED PRIOR      SHARES OFFERED BY THIS      PERCENTAGE OWNED FOLLOWING
             NAME                    TO THIS OFFERING                PROSPECTUS                    OFFERING (1)
             ----                -------------------------     ----------------------      --------------------------
                                                                                  
Brown Simpson                             556,407                      556,407                          0%
Strategic Growth Fund, L.P.

Brown Simpson                             947,397                      947,397                          0%
Strategic Growth Fund, Ltd.
- ---------------------------------------------------------------------------------------------------------------------


     (1)  Assumes all shares of Common Stock offered hereby are sold in this
          offering. There is no assurance that the Selling Stockholders will
          sell any or all of the shares of Common Stock offered hereby.




                                      -2-
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                              PLAN OF DISTRIBUTION

         The Company is registering the Common Stock ("Registrable Securities")
on behalf of the Selling Stockholders ("Holders"). As used herein, the term
Holder means the holder of the Registrable Securities and includes donees and
pledgees selling Registrable Securities received from a named Holder after the
date of this Prospectus. All costs, expenses and fees in connection with the
registration of the Registrable Securities offered hereby will be borne by the
Company. Brokerage commissions and similar selling expenses, if any,
attributable to the sale of Registrable Securities will be borne by the Holders.
Sales of Registrable Securities may be effected by Holders from time to time in
one or more types of transactions (which may include block transactions) on
Nasdaq, on the BSE, in the over-the-counter market, in negotiated transactions,
through put or call options transactions relating to the Registrable Securities,
through short sales of Registrable Securities, or a combination of such methods
of sale, at market prices prevailing at the time of sale, or at negotiated
prices. Such transactions may or may not involve brokers or dealers. The Holders
have advised the Company that they have not entered into any agreements,
understandings or arrangements with any underwriters or broker-dealers regarding
the sale of their securities, nor is there an underwriter or coordinated broker
acting in connection with the proposed sale of Registrable Securities by the
Holders.

         The Holders may enter into hedging transactions with broker-dealers or
other financial institutions. In connection with such transactions,
broker-dealers or other financial institutions may engage in short sales of the
Registrable Securities or of securities convertible into or exchangeable for the
Registrable Securities in the course of hedging positions they assume with
Holders. The Holders may also enter into options or other transactions with
broker-dealers or other financial institutions which require the delivery to
such broker-dealers or other financial institutions of Registrable Securities
offered by this Prospectus, which Registrable Securities such broker-dealer or
other financial institution may resell pursuant to this Prospectus (as amended
or supplemented to reflect such transaction).

         The Holders may effect such transactions by selling Registrable
Securities directly to purchasers or to or through broker-dealers, which may act
as agents or principals. Such broker-dealers may receive compensation in the
form of discounts, concessions or commissions from Holders and/or the purchasers
of Registrable Securities for whom such broker-dealers may act as agents or to
whom they sell as principal, or both (which compensation as to a particular
broker-dealer might be in excess of customary commissions).

         The Holders and any broker-dealers that act in connection with the sale
of Registrable Securities might be deemed to be "underwriters" within the
meaning of Section 2(11) of the Securities Act, and any commissions received by
such broker-dealers and any profit on the resale


                                      -3-
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of the Registrable Securities sold by them while acting as principals might be
deemed to be underwriting discounts or commissions under the Securities Act. The
Company has agreed to indemnify each Holder against certain liabilities,
including liabilities arising under the Securities Act. The Holders may agree to
indemnify any agent, dealer or broker-dealer that participates in transactions
involving sales of the Registrable Securities against certain liabilities,
including liabilities arising under the Securities Act.

         The Holders may be deemed to be "underwriters" within the meaning of
Section 2(11) of the Securities Act.

         The Holders will be subject to the prospectus delivery requirements of
the Securities Act. The Company has informed the Holders that the
anti-manipulative provisions of Regulation M promulgated under the Exchange Act
may apply to their sales in the market.

         Holders also may resell all or a portion of the Registrable Securities
in open market transactions in reliance upon Rule 144 under the Securities Act,
provided they meet the criteria and conform to the requirements of such Rule.

         Upon the Company being notified by a Holder that any material
arrangement has been entered into with a broker-dealer for the sale of
Registrable Securities through a block trade, special offering, exchange
distribution or secondary distribution or a purchase by a broker or dealer, a
supplement to this Prospectus will be filed, if required, pursuant to Rule
424(b) under the Securities Act, disclosing (i) the name of each such Holder and
of the participating broker-dealer(s), (ii) the number of Registrable Securities
involved, (iii) the initial price at which such Registrable Securities were
sold, (iv) the commissions paid or discounts or concessions allowed to such
broker-dealer(s), where applicable, (v) that such broker-dealer(s) did not
conduct any investigation to verify the information set out or incorporated by
referenced in this Prospectus and (vi) other facts material to the transactions.
In addition, upon the Company being notified by a Holder that a donee or pledgee
intends to sell more than 500 Registrable Securities, a supplement to this
Prospectus will be filed.

                 INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

         The following documents filed with the Commission by the Company are
incorporated by reference in this Prospectus:

          (1) the Company's Annual Report on Form 10-K for the year ended
December 31, 1998, as amended;

          (2) the Company's Quarterly Report on Form 10-Q for the three month
periods ended March 31, 1999.



                                      -4-
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          (3) the Company's Current Report on Form 8-K filed on May 28, 1999;
and



                                      -5-
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          (4) the description of the Company's Common Stock contained in the
Company's Registration Statement on form 8-A filed August 1, 1997, including any
amendment or report filed for the purposes of updating such description.

         All reports and other documents filed by the Company pursuant to
Sections 13(a), 14 or 15(d) of the Exchange Act after the date of this
Prospectus and prior to the termination of the offering of the Common Stock
shall be deemed to be incorporated by reference in this Prospectus and to be
part hereof from the date of filing of such documents. Any statement contained
herein or in a document incorporated or deemed to be incorporated by reference
herein shall be modified or superseded for purposes of this Prospectus to the
extent that a statement contained herein or in any other subsequently filed
document which also is or is deemed to be incorporated by reference herein,
modifies or supersedes such statement. Any statement so modified or superseded
shall not be deemed, except as so modified or superseded, to constitute a part
of this Prospectus.

         A copy of the documents incorporated by reference (other than exhibits
thereto) will be forwarded without charge to each person to whom this Prospectus
is delivered, upon such person's written or oral request to International
Isotopes Inc., Office of the Secretary, 3100 Jim Christal Road, Denton, Texas
76207-9987, telephone number (940) 484-9492. The Company's internet address is
ilmorgan@intiso.com.


                                  LEGAL MATTERS

         The validity of the shares of Common Stock offered hereby have been
passed upon for the Company by Locke Liddell & Sapp LLP, Austin, Texas.


                                     EXPERTS

         The consolidated financial statements of the Company as of December 31,
1997 and 1998 and for the years then ended and the periods from November 1, 1995
(inception) to December 31, 1996 and December 31, 1998 have been incorporated by
reference herein in reliance on the report of KPMG LLP, independent certified
public accountants, incorporated by reference herein and upon the authority of
said firm as experts in auditing and accounting.

                              AVAILABLE INFORMATION

         The Company is subject to the informational requirements of the
Securities Exchange Act of 1934 (the "Exchange Act") and accordingly files
reports and other information with the Securities and Exchange Commission (the
"Commission"). Reports, proxy statements and other


                                      -6-
   11

information filed by the Company with the Commission can be inspected and
copied, at prescribed rates, at the Public Reference Room maintained by the
Commission at 450 Fifth Street, N.W., Washington, DC 20549. The public may
obtain information on the operation of the Public Reference Room by calling the
Commission at 1-800-SEC-0330. The Commission maintains an Internet web site at
http://www.sec.gov/ that also contains such reports, proxy statements and other
information.

         The Company has filed with the Commission a Registration Statement on
Form S-3 (including all amendments thereto, the "Registration Statement") under
the Securities Act of 1933, as amended (the "Securities Act"), with respect to
the Common Stock offered hereby. The Registration Statement has been filed
electronically with the Commission pursuant to its Electronic Data Gathering and
Retrieval ("EDGAR") system. As permitted by the rules and regulations of the
Commission, this Prospectus does not contain all the information set forth in
the Registration Statement.



                                      -7-
   12


                                     PART II

Information Not Required in Prospectus


ITEM 13.      OTHER EXPENSES OF ISSUANCE AND DISTRIBUTION.

         The estimated expenses of this offering, all of which will be paid by
Registrant, are as follows:


                                                                  
         SEC Registration Fee                                        $  3,775.58
         Nasdaq Listing Fee                                          $  7,500.00
         Accounting Fees and Expenses                                $  5,000.00
         Registrant's Legal Fees and Expenses                        $ 20,000.00

             Total                                                   $ 36,275.58


ITEM 14.      INDEMNIFICATION OF DIRECTORS AND OFFICERS

         As permitted by the Texas Business Corporation Act ("TBCA"), the
Company's Restated Articles of Incorporation provide that the Company will
indemnify its officers, directors, employees and agents to the fullest extent
permitted by the TBCA against actions that may arise against them in such
capacities, and advance expenses in connection with any such actions.
Registrant's Restated Articles of Incorporation provide that directors of the
Company will not be personally liable to Registrant or its stockholders for
monetary damages for any act or omission in his capacity as a director except as
authorized under the TBCA. The TBCA provides that a corporation may indemnify a
person who was, is, or is threatened to be made a named defendant in a
proceeding because such person is or was a director if it is determined in
accordance with the provisions of the TBCA that the person (i) conducted himself
in good faith, (ii) reasonably believed, in the case of conduct in his official
capacity as director, that his conduct was in the corporation's best interests
or, in other cases, that his conduct at least was not opposed to the
corporation's interests and (iii) in the case of any criminal proceeding, had no
reasonable cause to believe his conduct was unlawful. A director may not be
indemnified with respect to a proceeding in which the person is found liable on
the basis that personal benefit was improperly received by him, whether or not
the benefit resulted from an action taken in the person's official capacity, or
in which the person is found liable to the corporation. Officers, employees and
agents of a corporation are entitled to be indemnified by the corporation as,
and to the same extent provided for, directors of the corporation.

         Registrant carries directors' and officers' liability insurance with an
aggregate policy limit of $5,000,000.




                                      II-1
   13





ITEM 16.   EXHIBITS.

Exhibits

4.1  Specimen Common Stock Certificate (incorporated by reference to Exhibit 4.1
     to the Company's Registration Statement on Form SB-2 (Registration No.
     333-26269)).

4.2  Form of Warrant issued to Selling Stockholders.

4.3  Certificate of Designation, Preferences and Rights of 5% Convertible
     Redeemable Preferred Stock.

4.4  Securities Purchase Agreement between the Selling Stockholders and the
     Company.

5.   Opinion of Locke Liddell & Sapp LLP with respect to the legality of the
     securities being registered hereby.

23.1 Consent of KPMG LLP

23.2 Consent of Locke Liddell & Sapp LLP (included in Exhibit 5).

24   Power of Attorney (included as part of Signature page).

ITEM 17.          UNDERTAKINGS.

         Insofar as indemnification for liabilities arising under Securities Act
may be permitted to directors, officers and controlling persons of Registrant
pursuant to the provisions of its Restated Articles of Incorporation, its
By-Laws, the Texas Business Corporation Act or otherwise, Registrant has been
advised that in the opinion of the Securities and Exchange Commission such
indemnification is against public policy as expressed in the Securities Act and
is, therefore, unenforceable. In the event that a claim for indemnification
against liabilities (other than the payment by Registrant for expenses incurred
or paid by an officer, director or controlling person of Registrant in the
successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, Registrant will, unless in the opinion of its counsel the matter has
been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue.

          (a)  The undersigned Registrant hereby undertakes:

               (1) To file, during any period in which offers or sales are being
made, a post-effective amendment to this registration statement:

                    (i)  To include any prospectus required by Section 10(a) (3)
of the Securities Act;

                    (ii) To reflect in the prospectus any facts or events
arising after the effective date of the registration statement (or the most
recent post-effective amendment thereof)

                                      II-2
   14

which, individually or in the aggregate, represent a fundamental change in the
information set forth in the registration statement; and

                    (iii) To include any material information with respect to
the plan of distribution not previously disclosed in the registration statement
or any material change to such information in the registration statement;

        Provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply
if the information required to be included in a post-effective amendment by
those paragraphs is contained in periodic reports filed by the Registrant
pursuant to Section 13 or Section 15(d) of the Exchange Act that are
incorporated by reference in the Registration Statement.

                  (2) That, for the purpose of determining any liability under
the Securities Act, each such post-effective amendment shall be deemed to be a
new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

                  (3) To remove from registration by means of a post-effective
amendment any of the securities being registered which remain unsold at the
termination of the offering.

                  (4) For purposes of determining any liability under the
Securities Act, the information omitted from the form of prospectus filed as
part of this registration statement in reliance upon Rule 430A and contained in
a form of prospectus filed by the registrant pursuant to Rule 424(b)(1) or (40
or 497(b) under the Securities Act shall be deemed to be part of this
Registration Statement as of the time it was declared effective.

         (b) The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
Exchange Act that is incorporated by reference in the registration statement
shall be deemed to be a new registration statement relating to the securities
offered therein, and the offering of such securities at that time shall be
deemed to be the initial bona fide offering thereof.


                                      II-3
   15






                      POWER OF ATTORNEY TO SIGN AMENDMENTS

        KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears
below does hereby constitute and appoint IRA LON MORGAN and CARL W. SEIDEL, and
each of them, with full power to act without the other, his true and lawful
attorney-in-fact and agent for him and in his name, place and stead, in any and
all capacities, to sign any or all amendments to this Registration Statement and
to file the same, with all exhibits thereto, and other documents in connection
therewith, with the Securities and Exchange Commission, granting unto said
attorneys-in-fact and agents, and each of them, full power and authority to do
and perform each and every act and thing requisite and necessary to be done in
and about the premises in order to effectuate the same, as fully, for all
intents and purposes, as he might or could do in person, hereby ratifying and
confirming all that said attorneys-in-fact and agents, or any of them, may
lawfully do or cause to be done by virtue hereof.


                                   SIGNATURES

        In accordance with the requirements of the Securities Act of 1933,
Registrant certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-3 and authorized this Registration
Statement to be signed on its behalf by the undersigned, in the City of Denton,
State of Texas, on the 8th day of July, 1999.



                                     INTERNATIONAL ISOTOPES INC.



                                     By: /s/ Ira Lon Morgan.
                                         ---------------------------------------
                                             Ira Lon Morgan, Ph.D.
                                             Chairman of the Board and Treasurer



                                     By: /s/ Carl W. Seidel.
                                         ---------------------------------------
                                             Carl W. Seidel
                                             President, Chief Executive
                                             Officer and Director



                                      II-4
   16


              In accordance with the requirements of the Securities Act of 1933,
this Registration Statement has been signed by the following persons in the
capacities and on the dates stated.




        SIGNATURE                              TITLE                              DATE


                                                                        
/s/ Carl W. Seidel                President, Chief Executive                  July 8, 1999
- --------------------------        Officer, and Director (Principal
Carl W. Seidel                    Executive Officer)



/s/ Joan Gillett                  Chief Financial Officer                     July 8, 1999
- --------------------------        (Principal Financial and
Joan Gillett                      Accounting Officer)



/s/ Ira Lon Morgan                Chairman of the Board and                   July 8, 1999
- --------------------------        Treasurer
Ira Lon Morgan, Ph.D.


/s/ Tommy L. Thompson             Executive Vice President, Chief             July 8, 1999
- --------------------------        Operating Officer and Director
Tommy L. Thompson


/s/ Virgil L. Simmons             Senior Vice President and Director          July 8, 1999
- --------------------------
Virgil L. Simmons


/s/ John M. McCormack             Director                                    July 8, 1999
- --------------------------
John M. McCormack


/s/ William W. Nicholson          Director                                    July 8, 1999
- --------------------------
William W. Nicholson


/s/ Robert J. Gary                Director                                    July 8, 1999
- --------------------------
Robert J. Gary

 /s/ Frederick J. Bonte           Director                                    July 8, 1999
- --------------------------
Frederick J. Bonte, M.D.

/s/ Charles LeMaistre             Director                                    July 8, 1999
- --------------------------
Charles LeMaistre, M.D.




                                      II-5
   17


                                  EXHIBIT INDEX

EXHIBIT NO.

4.1  Specimen Common Stock Certificate (incorporated by reference to Exhibit 4.1
     to the Company's Registration Statement on Form SB-2 (Registration No.
     333-26269)).

4.2  Form of Warrant issued to Selling Stockholders.

4.3  Certificate of Designation, Preferences and Rights of 5% Convertible
     Redeemable Preferred Stock.

4.4  Securities Purchase Agreement between the Selling Stockholders and the
     Company.

5    Opinion of Locke Liddell & Sapp LLP with respect to the legality of the
     securities being registered hereby.

23.1 Consent of KPMG LLP

23.2 Consent of Locke Liddell & Sapp LLP (included in Exhibit 5).

24   Power of Attorney (included as part of Signature page).