The group is especially concerned about some chemicals which it says "turn up regularly" and "are known or suspected hormone disrupters which can work on the hormone system at very low levels".

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Its onset probably has to do with significant changes in the neuroendocrine (brain-hormone) system leading up to and occurring just after birth.

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PT141 is a copy of a hormone which has an effect on the nervous system called alpha-melanocyte-stimulating hormone.

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Suspected human carcinogen, interferes with normal reproductive system development and thyroid hormone levels.

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Researchers found that people with CFS produced unusually high levels of the hormone melatonin, which stimulates the immune system and plays an important role in promoting sleep.

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Research indicates that doing good deeds, volunteering or being altruistic actually floods your system with serotonin - the feel good hormone.

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