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World consumption of 37% formaldehyde was about 28 million metric tons in
2006, up from 24 million metric tons in 2003. Between 2003 and 2006, world
capacity grew at an average annual rate of 3.9%, while world consumption grew
at an average annual rate of 5.4%.
Formaldehyde is the most commercially important aldehyde. Urea-, phenol- and
melamine-formaldehyde resins (UF, PF and MF resins) accounted for nearly 63%
of world demand for formaldehyde in 2006; other large applications include
polyacetal resins, pentaerythritol, methylenebis(4-phenyl isocyanate) (MDI),
1,4-butanediol (BDO) and hexamethylenetetramine (HMTA). Most formaldehyde producers
are concerned primarily with satisfying captive requirements for derivatives
and/or supplying local merchant sales. Formaldehyde is usually produced close
to the point of consumption since it is fairly easy to make, is costly to transport
and can develop problems associated with stability during transport. As a result,
world trade in formaldehyde is minimal and accounted for approximately 2% of
production in 2006.
Construction/remodeling activity, vehicle and furniture production, and original
equipment manufacture (OEM) account for most world consumption of formaldehyde.
Demand in these markets is greatly influenced by general economic conditions.
As a result, demand for formaldehyde largely follows the patterns of the leading
world economies. Formaldehyde resins are used predominantly in the wood products
industry as adhesives. Growth of these resins is strongly correlated with construction/remodeling
activity, which accounts for over 50% of consumption, and to a lesser degree,
the automotive industry.
The following pie chart shows consumption of formaldehyde by end use:
Concern over possible human carcinogenicity of formaldehyde has been a controversial
issue. Many studies assessing the human risk of low-level exposure to formaldehyde
have been conducted; interpretation of study findings has been varied. The
lack of conclusive evidence has led to widespread disagreement among industry,
government agencies and unions regarding the appropriate risk assessment of
formaldehyde.
In 1987, the U.S. Occupational Safety and Health Administration (OSHA) adopted
a comprehensive formaldehyde workplace standard of one ppm permissible exposure
limit (PEL) based on an eight-hour time-weighted average (TWA). A fifteen-minute
short-term exposure limit (STEL) of 2 ppm and an “action level” of
0.5 ppm were also adopted. A number of ancillary requirements, including exposure
monitoring, medical surveillance, hazard communication, training and respiratory
protection, were also established. In 1992, the PEL was reduced to 0.75 ppm
on an eight-hour TWA. Medical removal protection (MRP) provisions were added
for employees claiming certain adverse effects of formaldehyde exposure. In
those cases, MRP is triggered only after careful delineation of symptoms and
consideration of job transfer alternatives prior to employee removal. The 1992
amended standard also changed the formaldehyde labeling requirements. Labels
containing a warning that formaldehyde presents a potential cancer hazard are
necessary only for products where formaldehyde levels may potentially exceed
0.5 ppm.
Additionally, in response to a 1985 federal regulation by the U.S. Department
of Housing and Urban Development, both wood adhesive and pressed wood products
manufacturers modified production techniques to reduce formaldehyde off-gassing.
Formaldehyde levels in homes have dropped significantly and, at current levels,
below 0.1 ppm, health concerns are negligible.
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