EXTENSION
                             REVOLVING CREDIT MASTER
                                 PROMISSORY NOTE

$2,500,000.00                                              Princeton, New Jersey
                                                          as of January 19, 1999

     FOR VALUE RECEIVED,  the undersigned  WINDSWEPT  ENVIRONMENTAL GROUP, INC.,
TRADE-WINDS ENVIRONMENTAL RESTORATION,  INC., NORTH ATLANTIC LABORATORIES,  INC.
and  NEW  YORK  TESTING  LABORATORIES,   INC.   (individually  and  collectively
"Borrower")  jointly  and  severally  promise  to pay to the  order of  BUSINESS
ALLIANCE  CAPITAL  CORPORATION  (herein  called  "BACC") at 300 Alexander  Park,
Princeton, New Jersey, 08543, or such other address as BACC may notify Borrower,
such sum up to Two Million  Five  Hundred  Thousand  and 00/100  ($2,500,000.00)
Dollars,  together with interest as hereinafter  provided, as may be outstanding
on Advances by BACC to Borrower  under  Paragraph  2.1 of the Loan and  Security
Agreement  dated June 1, 1998  between  BACC and  Borrower  (said  Agreement  as
amended or modified from time to time the "Loan  Agreement").  Capitalized terms
not otherwise  defined herein have the meanings set forth in the Loan Agreement.
The Loan Agreement is incorporated herein as though fully set forth and Borrower
acknowledges its reading and execution. The principal amount due hereunder shall
be paid to BACC on December 1, 2000 or as may  otherwise  be provided for in the
Loan Agreement.

     On the first day of each month  hereafter,  Borrower shall pay BACC accrued
interest, computed on the basis of a 360 day year, for the actual number of days
elapsed,  on the daily unpaid balance of the Advances,  at the per annum rate of
three (3%) percentage  points above the Prime Rate, in effect from time to time.
If there is a change in the Prime Rate,  the rate of  interest  on the  Advances
shall be changed  accordingly  as of the date of the  change in the Prime  Rate,
without notice to Borrower.

     To secure  the  payment  of this  Note and the  Obligations,  Borrower  has
granted to BACC a continuing security interest in and lien on the Collateral. In
addition to all  remedies  provided by law upon default on payment of this Note,
or upon an Event of Default, BACC may, at its option:

          (1) Declare this Note and the Obligations immediately due and payable;

          (2) Collect interest on this Note at the default rate set forth in the
     Loan Agreement from the date of such Event of Default,  and if this Note is
     referred to an attorney for collection, collect reasonable attorneys' fees;
     and 

          (3) Exercise any and all remedies provided for in the Loan Agreement.

                                      -1-

<PAGE>



     This Note  represents  an extension  of that certain  Modified and Restated
Revolving Credit Master Promissory Note of Borrower to BACC in the principal sum
of $2,500,000.00 dated as of October 19, 1998 and is not intended to be novation
of said note or the loans evidenced thereby.

     BORROWER WAIVES PRESENTMENT FOR PAYMENT,  PROTEST AND NOTICE OF PROTEST FOR
NON-PAYMENT  OF THIS NOTE AND TRIAL BY JURY IN ANY ACTION  UNDER OR  RELATING TO
THIS NOTE AND THE ADVANCES EVIDENCED HEREBY.

                                     WINDSWEPT ENVIRONMENTAL GROUP, INC.


                                     By:      /s/ Michael O'Reilly
                                              ----------------------------------
                                              Name:    Michael O' Reilly
                                              Title:   President


                                     TRADE-WIND ENVIRONMENTAL
                                     RESTORATION, INC.


                                     By:      /s/ Michael O'Reilly
                                              ----------------------------------
                                              Name:    Michael O' Reilly
                                              Title:   President        
                                                       

                                     NORTH ATLANTIC LABORATORIES, INC.


                                     By:      /s/ Michael O'Reilly
                                              ----------------------------------
                                              Name:    Michael O' Reilly
                                              Title:   Vice President        
                                                       

                                     NEW YORK TESTING LABORATORIES, INC.

                                     By:      /s/ Micael O'Reilly
                                              ----------------------------------
                                              Name:    Michael O' Reilly
                                              Title:   Vice PresPresident       
                                                       

                                      -2-