For more than 30 years, American Chemistry Council companies have supported research to learn more about potential health and environmental effects of phthalates. By working together, member companies have supported millions of dollars of research to bring together experts to develop and implement important and often cutting edge research and in many cases, to develop techniques to address issues when they first surface.
Phthalates research, generally contracted for and carried out by independent laboratories in the private sector or in academia, is typically published in peer-reviewed journals. Publications describing the various research programs supported by ACC members are included in this section of the website. Apart from work sponsored by the Panel, phthalate producers have also individually undertaken a number of studies of phthalates. References to some major pieces of research sponsored by phthalate producers are also included in this section of the Web site.
In more than 50 years of use, a great quantity of research has been conducted on phthalates, not only by industry but also by universities, government agencies and independent laboratories. This body of research makes phthalates one of the most widely studied and thoroughly characterized family of chemicals in use today. The preponderance of the research has been conducted in animals including rodents and primates, but there is also some data from biomonitoring studies in humans. In addition, some data has been collected in human volunteer studies studying possible sensitization and irritation. Most of the experimental research on potential health effects of phthalates consists of laboratory rodent studies, where a range of doses up to the highest dose animals can tolerate are administered over periods of time from a few weeks to two years. The process the government generally uses to apply data from these rodent studies to humans is to find the highest dose that has no effect on the animals, (called a NOAEL for “no observed adverse effect level”), and then to divide by a safety factor ranging from 100 to 1,000 to establish safety levels for human exposure. Exposures for various demographic groups compare to the Reference Dose (RfD)3 set by EPA or safety levels set by other regulatory/scientific bodies can be found here:
Human Exposure and Biomonitoring.
Because there is such a huge body of research on phthalates, it is difficult to come to any conclusions about their safe use by looking at a few selective studies. Fortunately, comprehensive reviews of the major phthalates have recently been conducted both in Europe and the United States. The U.S. National Toxicology Program has issued final reports on six of the seven phthalates it reviewed, and found that, in most cases, the risk to human reproductive and developmental health is “minimal” or “negligible.” The European Union has published risk assessments for five phthalates. The EU risk assessments for DINP and DIDP found no need for further information and/or testing and for risk reduction measures beyond those which are being applied already.
Environmental research conducted by industry and others has led to a scientific consensus on two key points. First, phthalates are not persistent; they are quickly biodegraded in water and soil. Second, bioaccumulation and biomagnification are also not concerns; living organisms do not build up levels of phthalates over time, but break them down and eliminate them quickly.
ACC welcomes questions about the research it supports regarding phthalates.