This article draws heavily from studies, analysis and commentary available on the searchable databases at www.ourstolenfuture.org1
According to their manufacturers, the principle use of a class of chemicals known as phthalates (pronounced thall eights) "is to soften the popular plastic, polyvinylchloride" (known as PVC or vinyl) used in building materials such as flooring, wall covering, upholstery, and shower curtains.2
This month, for the first time, researchers have demonstrated a highly significant relationship between a mother's exposure during pregnancy to phthalates and changes in the ways that baby boys' genitals develop, including smaller penis size and incomplete testicular descent.3 The U.S. Centers for Disease Control has previously established that phthalate exposure is widespread in American women, and a 2003 study revealed a link between one phthalate compound and preterm birth.4
Also this month, a first-of-its-kind study released by Harvard University scientists found that babies in Neonatal Intensive Care Units (NICUs) receiving intensive therapy with PVC medical devices, such as IV bags and tubing, were exposed to a phthalate at very high levels — an average of 25 times higher than the general population and up to 50 times higher for the most exposed. As their medical treatments intensified, the sick infants were exposed to progressively higher exposures of Di(2-ethyl hexyl) phthalate or DEHP.5
Phthalates come in many different formulas. Most haven't been tested or examined at all for human health impacts. The Consumer Product Safety Commission has noted that one phthalate formula common to certain building materials — DINP6 — is a mixture of up to 100 chemical variants, of which only five have been minimally studied.7 Others have been found to pose a risk of serious negative health impacts at very low doses.
The new studies about harm to developing fetuses and newborn babies from phthalates are not conclusive. However, they reinforce the findings from other studies that have revealed associations between phthalates and human reproductive systems, such as reductions in semen quality detected in three studies between 2000 and 2003.8 One showed DNA damage in sperm. Two others found reductions in sperm quality in men with slightly elevated phthalate levels. These are consistent with laboratory results studying the effects of phthalates in animals, although they suggest that humans may be more sensitive than rodents.9
Phthalate levels associated with the damage in those studies were well within the range experienced by many Americans.10 The subjects all were men exposed to background, environmental levels of phthalates, not higher occupational levels. In March of this year, an analysis of ordinary household dust for seven chemicals found that phthalates accounted for 90% of the chemical concentration in the aggregate sample.11
Like the human carcinogens vinyl chloride and dioxin, phthalates are uniquely associated with PVC.12 It's this triple threat from PVC that distinguishes it as the worst plastic for environmental health and green building.
 A comprehensive discussion of the health risks associated with phthalates can be found at http://www.ourstolenfuture.org/NewScience/oncompounds/phthalates/phthalates.htm
 "Phthalates Information Centre Europe" http://www.phthalates.com/index.asp?page=54
 Swan, SH, KM Main, F Liu, SL Stewart, RL Kruse, AM Calafat, CS Mao, JB Redmon, CL Ternand, S Sullivan, JL Teague, EZ Drobnis, BS Carter, D Kelly, TM Simmons, C Wang, L Lumbreras, S Villanueva, M Diaz-Romero, MB Lomeli, E Otero-Salazar, C Hobel, B Brock, C Kwong, A Muehlen, A Sparks, A Wolk, J Whitham, M Hatterman-Zogg, M Maifield and The Study for Future Families Research Group 2005. Decrease in Anogenital Distance Among Male Infants with Prenatal Phthalate Exposure. Environmental Health Perspectives (in press). http://www.ourstolenfuture.org/NewScience/oncompounds/phthalates/2005/2005-0527swanetal.htm
 Latini, G, C de Felice, G Presta, A del Vecchio, I Paris, F Ruggieri and P Mazzeo. 2003. In utero exposure to di-(2-ethylhexyl)-phthalate and human pregnancy duration. Environmental Health Perspectives, on line 19 August 2003. http://www.ourstolenfuture.org/NewScience/oncompounds/phthalates/2003/2003-0820giuseppeetal.htm
 Green, R., R. Hauser, A. Calafat, J. Weuve, T. Schettler, S. Ringer, K. Huttner, H. Hu 2005. Use of Di(2-Ethylhexyl) Phthalate Containing Medical Products and Urinary Levels of Mono (2-Ethylhexyl) Phthalate in Neonatal Intensive Care Unit Infants. Environmental Health Perspectives http://ehp.niehs.nih.gov/docs/2005/7932/abstract.html
 Diisononyl phthalate, a general use vinyl plasticizer. It is the primary plasticizer used in vinyl toys, though it finds many other applications such as garden hoses, shower curtains, vinyl flooring and wall covering. Source: http://www.phthalates.org/glossary.asp
 "Aggregate Exposures to Phthalates in Humans," Health Care Without Harm, July 2002. See http://www.noharm.org/lib/downloads/pvc/Agg_Exposures_to_Phthalates.pdf, p.16, footnote 149
 See discussion and full citations at http://www.ourstolenfuture.org/NewScience/oncompounds/phthalates/phthalates.htm
 Duty, SM, MJ Silva, DB Barr, JW Brock, L Ryan, Z Chen, RF Herrick, DC Christiani and R Hauser 2003. Phthalate Exposure and Human Semen Parameters. Epidemiology 14:269 -277. http://www.ourstolenfuture.org/NewScience/reproduction/sperm/2003/2003-0519dutyetal.htm
 Sick of Dust is the first U.S. study to find organotins and perfluorinated compounds in household dust. See the Sick of Dust report at http://www.safer-products.org. In addition to the phthalates, organotins and brominated flame retardants discussed in this article, the testing also detected pesticides, alkylphenols (used as emulsifiers, lubricants or anti-oxidants in laundry detergents, textiles, leather, paints, disinfecting cleaners, all-purpose cleaners, spot removers, hair-coloring, cosmetics, adhesives, some plastics and pesticides), and perfluorinated compounds (used as floor polishes, adhesives, and in oil-, water-, and stain-resistant products, like Teflon and Goretex, which are found in common products like non-stick pans, clothing, stainproof carpets, and furniture).
 Dioxin is also a byproduct of petroleum refining, and in that sense is associated with all petroleum-based plastics. However, the chlorine content of PVC leads to much greater dioxin emissions during production, use (when PVC is burned) and disposal.