26 March 2004
Reproductive Problems Linked To High Plasticiser Levels
by Kate Melville
Phthalates, widely used as plasticisers, have for some time been connected with rising infertility rates in men. These substances are relatively common and are considered highly hazardous to human health because they disrupt the hormonal balance and impair reproduction and development. What has not been clear up to now is the amount of phthalates that enter the human body. Now, the Deutsche Forschungsgemeinschaft (DFG - German Research Foundation) is funding a research project at the University of Erlangen-N�rnberg under the leadership of Professor J�rgen Angerer that is studying the environmental uptake of phthalates in the population. The results have shown that the levels observed so far are much higher than previously believed, especially in children. German and European authorities have already begun to react to the findings of the researchers from Erlangen.
Phthalates such as the plasticiser di(2-ethylhexyl)phthalate (DEHP) are widely used industrial chemicals and are produced in large quantities. Of the 2 million tonnes of DEHP produced each year, 90% are used as plasticisers for PVC.
Phthalates are also used in many other areas, such as the production of toiletry products and textiles, and are consequently omnipresent in the environment. Human exposure to phthalates comes mainly from food, where it enters the organism and disrupts the hormonal balance.
Researchers and international expert committees draw a link between phthalate intake and the decline in human sperm counts and male fertility. The rise in testicular cancer and male genital deformities has also been discussed in connection with phthalate exposure. The researchers from Erlangen have demonstrated that humans are exposed to phthalates in far greater quantities than had been previously believed. In some cases the measurements even exceed the tolerable daily intake (TDI).
These findings have caused concern, not only in scientific circles, but also among German and European authorities. The Scientific Committee on Toxicity, Ecotoxicity and Environment (SCTEE) of the European Commission has largely adopted the findings of the researchers from Erlangen. This applies to the unexpectedly high burden on the general population due to DEHP as well as to the new discoveries on the metabolic behaviour of this phthalate. The expanded test method used in the DFG project, which provides more precise and more reliable measurements, was also accepted.
The researchers have pointed out that infants and children - who are especially sensitive in their reactions to hormones - should be protected in the re-evaluation of the health risks associated with DEHP. This has prompted the German Federal Environmental Agency to work together with the Institute of Occupational, Social and Environmental Medicine at the University of Erlangen-N�rnberg on research efforts.