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in the urine, the sperm were on average slower moving. Reduced sperm quality can be connected to low fertility, states Russ Hauser, the supervisor of the study.
In Germany, toxicologist Jürgen Angerer from the Erlangen University has developed new methods for analysing phthalates. His research team analysed, for the first time ever, the phthalate concentration in the urine of German study participants and detected values even higher than those found in the American study. Women in this study had a higher burden of MBP than men. According to Angerer, the fact that animal tests have shown that higher dosages do damage the reproductive system, is terrifying. The latest research shows that normal daily amounts of phthalates might be sufficient to lower your fertility. These studies should serve as an alarm call. Researchers have warned for a long time that sperm quality has decreased in the last decades, although results haven't always been definitive.
A multitude of other substances (mainly industry chemicals and pesticides) is also under suspicion. It is suspected that they have hormonal properties. Alone, they appear to have a minimal effect on the bodys own hormones but combined they can become a fatal cocktail for both the environment and for man.
Chemicals that have been made illegal are still abundantly found in the environment and also affect sperm quality. This has been reported by scientists in Human Reproduction: researchers under the supervision of Marcello Spanò examined sperm cells from 700 men originating from different geographic regions. At the same time, it was determined through blood tests up to what extent participants were exposed in their local environment to polychlorinated biphenyls (PCBs). PCBs are used for, among other things, the manufacturing of plastic products. In the process, it was shown that genetic damage to sperm were more pronounced when the man had more contact with environmental toxins. In total, around 10% of the sperm cells were damaged this way. The BBC reported that this proportion doesn't affect fertility. The value for damage to fertility is believed to begin at 20%. Nevertheless, PCBs do have negative effects on the fertility of some men - mainly if the sperm quality is already low due to other reasons. An exception in the study was found in the group of Inuit men from Greenland (the other men in the study were from Warsaw (Poland), Kharkiv (Ukraine) and fishermen from Sweden). These men showed no connection between PCBs and sperm quality, possibly suggesting genetic or lifestyle factors in this group weakened the damaging effect of PCBs on their sperm.
The EU wishes to conduct new studies. Meanwhile, it has assessed a few environmental hormones, including two phthalates which have subsequently been banned since 2004 in the manufacturing of paints and cosmetics, although they are still allowed in PVC floors, plastic tableware and infusion tubes.
The EU has also started (2002) the EUR 20-million project CREDO (Cluster of Research on Endocrine Disruption in Europe). 64 teams from 16 countries are working together. Finally, a multidisciplinary force is considering the health and environmental issues caused by hormonally active substances - they have a big task ahead of them, the EU has 553 chemicals registered as potentially dangerous.
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