Now, from bottled water to sippy cups and other plastic products company, is in the heart of the advertising "does not contain bisphenol A (BPA)" trumpeted as A security indicators. The United States, however, according to A new study at the university of California, Los Angeles, A substitute material of bisphenol A bisphenol S (BPS) can accelerate the embryonic development and disrupt the reproductive system. 　　Published in the journal secretion to learn the study, by animal testing for the first time the bisphenol A and bisphenol S key to control the growth of brain cells and participate in the influence of the function of the reproductive organs. Study senior author, David geffen school of medicine professor of physiology, reproductive endocrinologist Nancy Wayne said, studies have shown that make bisphenol A substitute for the plastic is not necessarily more secure. 　　The researchers chose zebrafish as experimental object, because of zebrafish embryos transparent, convenient "observation" cell growth change. They found that exposure to low level (in the polluted river water content) bisphenol A and bisphenol S, zebrafish embryo development stage changed in 25 hours, than in contains no bisphenol A or bisphenol S fast development A lot of water. Wayne said, hatch eggs acceleration means that the premature birth. 　　The researchers also using green fluorescent protein markers that can track the brain of fish control reproductive and endocrine cell development. They found that endocrine unexpectedly increased by 40% the number of neurons, suggests that bisphenol A is to adjust the reproductive system. Wayne said that bpa exposure to low level control of embryonic development of the brain cells have A significant impact, as "the effect also exists in bisphenol S products, bisphenol S is not harmless". 　　Surprisingly, the study also found that bisphenol A and bisphenol S by estrogen system not only, also can influence through parts of the thyroid hormone system. Wayne explained that thyroid hormone is very important to brain development during pregnancy, so this study is of great significance to human embryonic and fetal development. 　　The study's data also support the proposed by academic circles after endocrine disrupters "chemicals led to human premature birth and early puberty" hypothesis. Wayne's lab is going to in the next study, explore the neurons to excessive regulation may lead to early puberty arrives and reproductive system development is interrupted.