On the PS foam heated release dimer, trimer, will produce environmental hormones (Chinese translation for 'hormone'), disrupt human endocrine effects of estrogens, is following the dioxin PS foam plastic tableware being love most severely criticized the toxic problem, and caused people's great concern and worry.
　　The problem for Kawamura Hako Japan national medical health products research et al, on May 13, 1998, the Japanese Health Association published an article entitled "food with polystyrene products of styrene oligomers" paper, by some media speculation, in Japan also once caused ideological confusion. Japanese government attaches great importance to the work of a lot of research and analysis and evaluation, currently on the PS foam tableware release styrene, two polymer, melamine problem has been basically clarified. First Japan polystyrene Industry Association commissioned TNO (Netherlands Organization for applied scientific research) and food and drug safety center and other research institutions, safety confirmation test, and publicly as a result, the dimer and trimer: the "Declaration on security", declared the disturbed the end of human endocrine function.
　　Environment Agency of Japan in July 2000 held first disrupt endocrine chemical substances seminar that conclusion is: "in detection of stilbene poly body, a trimer of risk is not realistic, so there is no need to consider that the conclusion is it to no longer included in the survey. The office in 2000 October 31 meeting of the year 2000, the second session of the "endocrine disrupting chemicals" seminar on announced decided not to styrene dimer, trimer and butyl benzene and other chemicals, included in the Department of production of environmental hormones "list. The office also decided to revised "speed '98" and renumbering the 2000 version of November, officially announced: Polyethylene second protomer, Sanyuan body, 67 species "list of suspicious chemical substances of environmental hormones removed from. In addition, for styrene dimer, trimer, the Japanese Ministry of health and welfare, MITI, the Ministry of agriculture, forestry and Fisheries and other also has made it clear that they do not belong to the so-called disturb endocrine chemicals. And that there is no need to carry out the test. According to this, the Japanese government has officially for the past few years has been trapped scratch PS foam tableware and PS products industry in the community's environmental hormone disturbance problem to draw a full stop.
　　In recent years, foreign countries have also been published in the relevant report research results, to clarify the issue of environmental hormones.
　　And international authority Holland applied scientific research institutions (TNO) test showed that with styrene dimers and trimers in the ethanol extracts of the main components of PS, from low dosage to wide range high dosage of there is no estrogenic properties. (June 1998.)
　　And instant food industry association of Japan in Nissin food central research experiments show that styrene dimer, trimer with estrogenic properties (June 1998)
　　The American Plastics Industry Association (SPI) under strict conditions to extract PS, the estrogen test, the results show that it does not have the nature of estrogen (September 1998)
　　European SSC (STEERING COMMITTEE STYRENE) has been on the 23 kinds of PS products of the female hormone test results show that it is not found with the nature of estrogen (1998)
　　European eco toxicology and Environmental Science Research Association (CSTEE) clearly shows that the harm to humans and the opposite sex have not been recognized (March 1999) by the PS, which has been thought to disrupt the body's endocrine system.
　　- the United States National Academy of Sciences (NRC) in a piece of "environmental hormone activity of drug" report showed that a certain organization or consumer associations: PS foam containers will be dangerous or toxic speech, there is no any scientific basis (August 1999)