as the united states not requiring them to be disclosed in a list of ingredients. endocannabinoid system disruption phthalates block cb1 as allosteric antagonists. other effects there may be a link between the obesity epidemic and endocrine disruption and metabolic interference. studies conducted on mice exposed to phthalates in utero did not result in metabolic disorder in adults. however, "in a national cross-section of u.s. men, concentrations of several prevalent phthalate metabolites showed statistically significant correlations with abnormal obesity and insulin resistance." mono-ethylhexyl-phthalate (mehp), a metabolite of dehp, has been found to interact with all three peroxisome proliferator-activated receptors (ppars). ppars are members of the nuclear receptor superfamily. the author of the study stated "the roles of ppars in lipid and carbohydrate metabolism raise the question of their activation by a sub-class of pollutants, tentatively named metabolic disrupters." phthalates belong to this class of metabolic disruptors. it is a possibility that, over many years of exposure to these metabolic disruptors, they are able to deregulate complex metabolic pathways in a subtle manner. in order to build up adipose tissue and establish metabolic homeostasis, it has been established that early childhood and puberty are crucial developmental stages. exposure to endocrine disruptors, such as phthalates, during these crucial developmental stages may negatively affect adipose tissue function and metabolic homeostasis, increasing the risk of obesity. the prevalence of obesity, particularly in children, is rising, according to mounting evidence, which suggests that increased exposure to phthalates through food packaging materials is to blame. in a study conducted on schoolchildren in china, the concentration of mono-n-butyl phthalate (mnbp) was assessed in urine samples. additionally, increased exposure to phthalates has been linked to an increase in mnbp. mnbp has been linked to significant increases in weight and obesity in schoolchildren. significant increases in mnbp concentration were found in the study's urine samples. the disruption of the arginine and proline metabolism associated with this elevated mnbp concentration as a result of phthalate exposure is thought to be a factor in the pathophysiological changes associated with childhood obesity. large amounts of specific phthalates fed to rodents have been shown to damage their liver and testes, and initial rodent studies also indicated hepatocarcinogenicity. following this result, di(2-ethylhexyl) phthalate was listed as a possible carcinogen by iarc, ec, and who. later studies on primates showed that the mechanism is specific to rodents; humans are resistant to the effect. the carcinogen classification was subsequently withdrawn. legal status canada in 1994, a health canada assessment found that dehp and another phthalate product, b79p, were harmful to human health. the canadian federal government responded by banning their use in cosmetics and restricting their use in other applications. a more recent assessment in 2017 found that b79p and dehp may cause environmental damage. as of 2019, regulations to protect the environment against dehp and b79p have not yet been put into place. european union update on non-classified plasticisers and the european reach candidate classification including pending authorisation the use of some phthalates has been restricted in the european union for use in children's toys since 1999. dehp, bbp, and dbp are restricted for all toys; dinp, didp, and dnop are restricted only in toys that can be taken into the mouth. the restriction states that the amount of these phthalates may not be greater than 0.1% mass percent of the plasticized part of the toy. generally, the high molecular weight phthalates dinp, didp, and dphp have been registered under reach and have demonstrated their safety for use in current applications. they are not classified for any health or environmental effects. the low molecular weight products bbp, dehp, dibp, and dbp were added to the candidate list of substances for authorisation under reach in 2008–9, and added to the authorisation list, annex xiv, in 2012. this means that from february 2015 they are not allowed to be produced in the eu unless authorisation has been granted for a specific use, however they may still be imported in consumer products. the creation of an annex xv dossier, which could ban the import of products containing these chemicals, was being prepared jointly by the echa and danish authorities, and expected to be submitted by april 2016. in 2006 the dutch office of greenpeace uk sought to encourage the european union to ban sex toys that contained phthalates. united states during august 2008, the united states congress passed and president george w. bush signed the consumer product safety improvement act (cpsia), which became public law 110–314. section 108 of that law specified that as of february 10, 2009, "it shall be unlawful for any person to manufacture for sale, offer for sale, distribute in commerce, or import into the united states any children's toy or child care article that contains concentrations of more than 0.1 percent of" dehp, dbp, or bbp and "it shall be unlawful for any person to manufacture for sale, offer for sale, distribute in commerce, or import into the united states any children's toy that can be placed in a child's mouth or child care article that contains concentrations of more than 0.1 percent of" dinp, didp, dnop. furthermore, the law requires the establishment of a permanent review board to determine the safety of other phthalates. prior to this legislation, the consumer product safety commission had determined that voluntary withdrawals of dehp and diisononyl phthalate (dinp) from teethers, pacifiers, and rattles had eliminated the risk to children, and advised against enacting a phthalate ban. in another development in 1986, california voters approved an initiative to address their growing concerns about exposure to toxic chemicals. that initiative became the safe drinking water and toxic enforcement act of 1986, better known by its original name of proposition 65. in december 2013 dinp was listed as a chemical "known to the state of california to cause cancer" this means that, starting december 2014, companies with ten or more employees manufacturing, distributing or selling the product(s) containing dinp are required to provide a clear and reasonable warning for that product. the california office of environmental health hazard assessment, charged with maintaining the proposition 65 list and enforcing its provisions, has implemented a "no significant risk level" of 146 μg/day for dinp. identification in plastics some "type 3" plastics contain phthalates. phthalates are used in some, but not all, pvc formulations, and there are no specific labeling requirements for phthalates. pvc plastics are typically used for various containers and hard packaging, medical tubing and bags, and are labeled "type 3". however, the presence of phthalates rather than other plasticizers is not marked on pvc items. only unplasticized pvc (upvc), which is mainly used as a hard construction material, has no plasticizers. if a more accurate test is needed, chemical analysis, for example by gas chromatography or liquid chromatography, can establish the presence of phthalates. polyethylene terephthalate (pet, pete, terylene, dacron) is the main substance used to package bottled water and many sodas. products containing pete are labeled "type 1" (with a "1" in the recycle triangle). although the word "phthalate" appears in the name, pete does not use phthalates as plasticizers. the terephthalate polymer pete and the phthalate ester plasticizers are chemically different substances. despite this, however, a number of studies have found phthalates such as dehp in bottled water and soda. one hypothesis is that these may have been introduced during plastic recycling.