8
the more signifi cant (if not the most visible) contributions of the industrial ecology
fi eld thus far.
3.3 Material Flow Analysis
Material fl ow analysis ( MFA ) is the methodology for quantifying the stocks, fl ows,
inputs, and losses of a resource. It is sometimes used for mixed materials (e.g., construction minerals) but more commonly is directed to a specifi c resource such as a
particular metal or plastic. For specifi c resource applications, the methodology is
sometimes termed substance fl ow analysis ( SFA ). Early MFA research was conducted by Robert Ayres when he was at Carnegie Mellon University in Pittsburgh,
PA. In 1968, he and Alan Kneese contributed to a US Congress report arguing that
economic theory was at odds with the fi rst law of thermodynamics: materials could
not be “consumed” physically. Rather, emissions and wastes from economic activity could only be reduced by lowering the physical input into the economy. This
material balance approach was truly revolutionary for the environmental and economic thinking of that time; it predated the book by Georgescu–Roegen ( 1971 )
which is widely regarded as one of the seminal works in ecological economics. The
material balance approach provided the theoretical base for what today has become
material fl ow accounting (MFA) as well as part of a number of nations’ public statistics. Ayres’s initial MFA application was for emissions from metal processing
activities in the New Jersey–New York area (Ayres and Rod 1986 ), followed by a
comprehensive study of chlorine (Ayres 1997 , 1998 , Ayres and Ayres 1997 , 1999 ).
In the same general time period, the MFA approach was also developed in
Switzerland by Baccini and Brunner ( 1991 ), who produced an important book on
the topic.
The distinction between bulk MFA and SFA was described by Bringezu and
Moriguchi ( 2002 ), who categorized analyses from the perspective of substances,
materials, products, fi rms, and geographical regions, although MFA studies tended
to dominate early efforts.
The fi rst metal-specifi c SFA was directed at zinc in the United States over the
period of 1850–1990 (Jolly 1993 ); it showed that about three-quarters of potential
zinc losses to the environment were due to dissipative uses and landfi ll disposal.
Other early MFA studies included those for cobalt in the United States (Shedd
1993 ), vanadium in the United States (Hilliard 1994 ), and cadmium in the
Netherlands (van der Voet et al. 1994 ). In another early effort, Socolow and Thomas
( 1997 ) produced a MFA study for lead in the United States that called for the
integration of risk analysis and highlighted the importance of recycling and technological transformation. A seminal dynamic study (i.e., a time-dependent SFA) was
completed for aluminum in Germany by Melo ( 1999 ).
By 2000–2010, MFAs had been completed for most metals and in several countries (Chen and Graedel 2012 ) and for some polymers (Kleijn et al. 2000 ; Diamond
et al. 2010 ; Kuczenski and Guyer 2010 ). Data challenges continue to constrain the
T.E. Graedel and R.J. Lifset
the more signifi cant (if not the most visible) contributions of the industrial ecology
fi eld thus far.
3.3 Material Flow Analysis
Material fl ow analysis ( MFA ) is the methodology for quantifying the stocks, fl ows,
inputs, and losses of a resource. It is sometimes used for mixed materials (e.g., construction minerals) but more commonly is directed to a specifi c resource such as a
particular metal or plastic. For specifi c resource applications, the methodology is
sometimes termed substance fl ow analysis ( SFA ). Early MFA research was conducted by Robert Ayres when he was at Carnegie Mellon University in Pittsburgh,
PA. In 1968, he and Alan Kneese contributed to a US Congress report arguing that
economic theory was at odds with the fi rst law of thermodynamics: materials could
not be “consumed” physically. Rather, emissions and wastes from economic activity could only be reduced by lowering the physical input into the economy. This
material balance approach was truly revolutionary for the environmental and economic thinking of that time; it predated the book by Georgescu–Roegen ( 1971 )
which is widely regarded as one of the seminal works in ecological economics. The
material balance approach provided the theoretical base for what today has become
material fl ow accounting (MFA) as well as part of a number of nations’ public statistics. Ayres’s initial MFA application was for emissions from metal processing
activities in the New Jersey–New York area (Ayres and Rod 1986 ), followed by a
comprehensive study of chlorine (Ayres 1997 , 1998 , Ayres and Ayres 1997 , 1999 ).
In the same general time period, the MFA approach was also developed in
Switzerland by Baccini and Brunner ( 1991 ), who produced an important book on
the topic.
The distinction between bulk MFA and SFA was described by Bringezu and
Moriguchi ( 2002 ), who categorized analyses from the perspective of substances,
materials, products, fi rms, and geographical regions, although MFA studies tended
to dominate early efforts.
The fi rst metal-specifi c SFA was directed at zinc in the United States over the
period of 1850–1990 (Jolly 1993 ); it showed that about three-quarters of potential
zinc losses to the environment were due to dissipative uses and landfi ll disposal.
Other early MFA studies included those for cobalt in the United States (Shedd
1993 ), vanadium in the United States (Hilliard 1994 ), and cadmium in the
Netherlands (van der Voet et al. 1994 ). In another early effort, Socolow and Thomas
( 1997 ) produced a MFA study for lead in the United States that called for the
integration of risk analysis and highlighted the importance of recycling and technological transformation. A seminal dynamic study (i.e., a time-dependent SFA) was
completed for aluminum in Germany by Melo ( 1999 ).
By 2000–2010, MFAs had been completed for most metals and in several countries (Chen and Graedel 2012 ) and for some polymers (Kleijn et al. 2000 ; Diamond
et al. 2010 ; Kuczenski and Guyer 2010 ). Data challenges continue to constrain the
T.E. Graedel and R.J. Lifset