Exhibit 24

POWER OF ATTORNEY

	KNOW ALL MEN BY THESE PRESENTS, that the
undersigned hereby constitutes and appoints Sarah P.
Cecil, Aninda Katragadda, Christopher J. Denn, John M.
Mutkoski, and Robert E. Puopolo, and any one of them
acting singly, the true and lawful attorneys-in-fact
and agents, with full power of substitution and
resubstitution, for the undersigned and in the
undersigned's name, place and stead, in any and all
capacities (until revoked in writing) to execute for
and on behalf of the undersigned, in any and all of
the undersigned's capacities, any and all statements
on Forms 3, 4 and 5 with respect to the undersigned's
holdings of and transactions in securities issued by
Metabolix, Inc. (the "Company") in accordance with
Sections 16(a) of the Securities Exchange Act of 1934,
as amended (the "Exchange Act"), and any and all
regulations promulgated thereunder, and to file the
same, with all exhibits thereto, and any other
documents in connection therewith, with the Securities
and Exchange Commission, and with any other entity
when and if such is mandated by the Exchange Act or by
the By-laws of the National Association of Securities
Dealers, granting unto said attorneys-in-fact and
agents full power and authority to do and perform each
and every act and thing requisite and necessary fully
to all intents and purposes as the undersigned might
or could do in person thereby ratifying and confirming
all that said attorneys-in-fact and agents, or their
substitute or substitutes, may lawfully do or cause to
be done by virtue hereof.

	This Power of Attorney shall remain in full force
and effect until the undersigned is no longer required
to file Forms 3, 4 and 5 with respect to the
undersigned's holdings of and transactions in
securities issued by the Company, unless earlier
revoked by the undersigned in a signed writing
delivered to the foregoing attorneys-in-fact.

	IN WITNESS WHEREOF, this Power of Attorney has
been signed as of April 8, 2008.


Signature:	/s/ Joseph D. Hill

Name:  Joseph D. Hill