Phthalate exposure in the home
Phthalate exposure occurs through ingestion, contact, inhalation and parenteral exposure from medical devices that contain phthalates.24 Since phthalates leave biomarkers in the form of metabolites in human urine, exposure to them can be measured.
In an attempt to determine the effects of daily exposure to phthalates, Bonehag and colleagues studied a cohort of 10,852 children, also selecting 198 with persistent allergic symptoms and 202 without allergic symptoms.25 Dust samples from moldings and shelves in the children’s bedrooms were collected and examined for six phthalates – DEP, DiBP, DnBP, BBzP, DEHP and DiNP (used in children’s toys). DEHP was found in almost all samples; DnBP in 89%; and BBzP in 79%. They also found that:
- BBzP and DEHP were higher in bedrooms with PVC flooring than in bedrooms without such flooring.
- Children who had been diagnosed with rhinitis or eczema had higher BBzP concentrations in the bedroom dust compared with controls.
- Children with a diagnosis of asthma had higher levels of DEHP in the dust compared with controls. There was a dose-response relationship for asthma.
- Children who were atopic had the highest levels of BBzP in their bedrooms.
- No association was found for DnBP.
The same findings applied to both single and multi-family dwellings. The more rooms with PVC flooring, the higher the levels of BBzP and DEHP. Some of the physical characteristics26 of the homes and the level of different phthalates is shown in Figure 3.
|Phthalate levels related to features of homes|
|House or room feature||DEHP||BBzP||DnBP|
|Multi-family home (compared to a single family)||⬆||⬆||⬆|
|Bedroom with PVC flooring||⬆||⬆|
|PVC flooring in other rooms||⬆||⬆|
|High ventilation rate in bedroom||⬆|
|Concrete slab foundation (instead of basement)||⬆|
|Water leakage in past three years||⬆||⬆|
Phthalates and the elderly
It has been noted that being overweight with high blood lipids is associated with a diagnosis of diabetes. A study by Lind and colleagues found an unexpected connection between phthalates and diabetes in elderly men and women. An analysis of data provided by more than one thousand men and women, aged 70 years, found that even after adjusting for confounders such as obesity, smoking, blood lipids, and exercise levels, elevated phthalate levels doubled the risk of developing diabetes when compared with lower levels.27
Phthalates and lung function in children
Bonehag’s study (above) linked BBzP with skin and mucosal symptoms and DEHP with pulmonary symptoms. But other studies have also linked phthalate exposure to asthma and bronchial obstruction. Jaakkola et al followed 3754 children, born in 1992 and 1993, for 2 years. Of these, 251 with bronchial obstruction were matched with a control group according to date of birth. The researchers found that the risk of bronchial obstruction was related to both the presence of PVC flooring and textile wall materials, and that there was a relationship between bronchial obstruction and the exposure levels to the amount of PVC and other plasticizer-containing surface materials.28
An initial study (that requires replication) found that children born to women who were exposed to BBzP or DnBP during their third trimester had a 72% and 78% increased risk, respectively, of developing asthma between the age of 5 and 11 years when compared with children whose mothers had lower levels of exposure. The children with increased risk of asthma were also at increased risk of eczema.29 The researchers pointed out that the fetus is extremely vulnerable during pregnancy and exposure to phthalates constitutes a risk that can be reduced.
A population-based, cross-sectional study of 2568 Finnish children, aged 1 to 7, found a link between emissions from plastics and persistent wheezing, cough or phlegm – all related to the lower respiratory tract rather than the upper respiratory tract. Children exposed to such materials were also at risk for asthma and pneumonia.30
A recent study31 involving 244 children between the ages of 5 and 10 found detectable levels of phthalates in their urine. The children’s lung function was assessed using exhaled nitric oxide as a marker of inflammation. High levels of nitric oxide in exhaled breath were associated with high levels of the metabolites of DEP and BBzP in urine. The researchers concluded that exposure to these two phthalates increased the risk for asthma and airway inflammation.
Phthalates and lung function in adults
Research has also been conducted on adults. Hoppin et al looked at 240 adults in the Third National Health and Nutrition Examination Survey (NHANES III) and tested their urine for MBP, MEHP and MEP. Pulmonary function was also tested. A distinct correlation was found between pulmonary function and two phthalates: MBP was associated with reduction in PEF, FEV1 and FVC; and increases in MBP were inversely related to FEV1. MEP was connected with lower FVC and FEV1 values.32 The associations were distinctly gender-based with only males being affected. MEHP did not adversely affect pulmonary function.
Phthalates are semi-volatile organic compounds. Their contribution to indoor air pollution cannot be ignored because of the health risks they carry. Daily exposure to phthalates is relatively high in industrialized countries. Exposure in the home occurs mainly through inhalation, ingestion and also dermally. Their effects on both the upper and lower respiratory tract are of concern. While some phthalates have been tested individually, not all have been tested nor have they been tested in combination to determine their health risks. Concerned consumers should be referred to the Campaign for Safe Cosmetics at www.safecosmetics.org. 33
Individuals with asthma are advised to remove carpeting from bedrooms since carpeting is a reservoir for house dust mites. Now it appears that two more questions should be added to the asthma educator’s checklist: what kind of flooring is there in the bedroom and, in the case of infants, what kind of mattress is used for sleeping? PVC flooring has been linked with both upper and lower respiratory tract problems. The choices appear to be very limited and unsatisfactory. The alternatives of wood and ceramic tile are prohibitively expensive for many parents. There are no simple answers and more research is currently underway on phthalate levels in indoor air – a herculean task, but one urgently needed considering not only the multiple sources of exposure but the lack of research of the effects of exposure to different combinations of phthalates.
- Houlihan J, Brody C, Schwan B. 2002. Not Too Pretty: Phthalates, Beauty Products, and the FDA. Washington, DC:Environmental Working Group. Available: http://www.safecosmetics.org/downloads/NotTooPretty_report.pdf Retrieved Dec 30, 2014
- Liang Y1, Xu Y. Emission of phthalates and phthalate alternatives from vinyl flooring and crib mattress covers: the influence of temperature. Environ Sci Technol. 2014 Dec 16;48(24):14228-37. doi: 10.1021/es504801x. Epub 2014 Dec 5.
- www.atsdr.cdc.gov/phs/phs.asp?id=857&tid=167/ Accessed Dec 30, 2014
- Dodson RE, Nishioka M et al. Endocrine disruptors and asthma-associated chemicals in consumer products. Environ Health Perspect. 2012; 120(7):935-43. DOI:10.1289/ehp.1104052
- www.inchem.org/documents/ehc/ehc/ehc189.htm#SubSectionNumber:3.2.2 Retrieved Dec 30, 2014
- www.atsdr.cdc.gov/substances/toxsubstance.asp?toxid=65 Accessed Dec 30, 2014
- Center for the Evaluation of Risks to Human Reproduction. NTP-CERHR Expert Panel Report on Di-2-ethylhexyl phthalate. Science International, Alexandria. 2000
- Mallow EB, Fox MA. Phthalates and critically ill neonates: device-related exposures and non-endocrine toxic risks. Journal of Perinatology, 2014; DOI: 10.1038/jp.2014.157
- Hauser R, Duty S, Godfrey-Bailey L, Calafat AM. Medications as a source of human exposure to phthalates. Environ Health Perspect. 2004 May;112(6):751-3.
- Kelley KE, Hernandez-Diaz S et al. Identification of phthalates in medications and dietary supplement formulations in the United States and Canada. Environ Health Perspect. 2012; 120(3):379-84. doi: 10.1289/ehp.1103998
- Zota AR, Calafat AM, Woodruff TJ. Temporal trends in phthalate exposures: findings from the National Health and Nutrition Examination Survey, 2001–2010. Environ Health Perspect. 2014; DOI: 10.1289/ehp.1306681
- Kang JS, Morimura K, Toda C, Wanibuchi H, Wei M, Kojima N, Fukushima S. Testicular toxicity of DEHP, but not DEHA, is elevated under conditions of thioacetamide-induced liver damage. Reprod Toxicol. 2005 Nov 19; Abstract.
- Kavlock R, Boekelheide K, et al. NTP Center for the Evaluation of Risks to Human Reproduction: Phthalates - expert panel report on the reproductive and developmental toxicity of butyl benzyl phthalate. Reprod Toxicol. 2002;16:453–487.
- Schlezinger JJ, Howard GJ, Hurst CH, et al. Environmental and endogenous peroxisome proliferator-activated receptor gamma agonists induce bone marrow B cell growth arrest and apoptosis: interactions between mono(2-ethylhexyl)phthalate, 9-cis-retinoic acid, and 15-deoxy-Delta12, 14-prostaglandin J2. J Immunol. 2004 ;173(5): 3165-77
- Duty SM, Singh NP, Silva MJ et al. The relationship between environmental exposures to phthalates and DNA damage in human sperm using the neutral comet assay. Environ Health Perspect 2003; 111: 1164-1169 Abstract.
- Blount BC, Silva MJ, Caudill SP, et al. Levels of seven urinary phthalate metabolites in a human reference population. Environ Health Perspect. 2000 Oct;108(10):979-82.
- Swan SH, Main KM, et al. Decrease in anogenital distance among male Infants with prenatal phthalate exposure. Environ Health Perspect 2005; 113: 1056-1061 Abstract.
- Bornehag CG, Carlstedt F, et al. Prenatal phthalate exposures and anogenital distance in Swedish boys. Environ Health Perspect. , 2014; DOI: 10.1289/ehp.1408163
- Ferguson KK, McElrath TF, Chen YH et al. Urinary phthalate metabolites and biomarkers of oxidative stress in pregnant women: a repeated measures analysis. Environ Health Perspect. November 2014 DOI: 10.1289/ehp.1307996
- Ferguson KK, McElrath TF, Meeker JD. Environmental phthalate exposure and preterm birth. JAMA Pediatrics, 2013; DOI: 10.1001/jamapediatrics.2013.3699
- Whyatt RM, Liu X, Rauh VA et al. Maternal prenatal urinary phthalate metabolite concentrations and child mental, psychomotor and behavioral development at age three years. Environ Health Perspect. 2011; DOI: 10.1289/ehp.1103705
- Miodovnik A1, Engel SM, Zhu C et al. Endocrine disruptors and childhood social impairment. Neurotoxicology. 2011 Mar;32(2):261-7. doi: 10.1016/j.neuro.2010.12.009.
- Factor-Litvak P, Insel B, Calafat AM et al. Persistent associations between maternal prenatal exposure to phthalates on child IQ at age 7 years. PLoS ONE, 2014; 9 (12): e114003 DOI: 10.1371/journal.pone.0114003
- Adibi JJ, Perera FP, Jedrychowski W et al. Prenatal exposures to phthalates among women in New York City and Krakow, Poland. Environ Health Perspect. 2003; 111(14): 1719–1722.
- Bornehag CG, Sundell J, Weschler CJ et al. The association between asthma and allergic symptoms in children and phthalates in house dust: a nested case–control study. Environ Health Perspect. 2004; 112(14): 1393–1397.
- Bornehag CG, Lundgren B, Weschler CJ et al. Phthalates in indoor dust and their association with building characteristics. Environ Health Perspect. 2005;113(10): 1399-404
- Lind PM, Zethelius B, and Lind L. Circulating levels of phthalate metabolites are associated with prevalent diabetes in the elderly. Diabetes Care, April 12, 2012 DOI: 10.2337/dc11-2396
- Jaakkola JJ, Oie L, Nafstad P, et al. Interior surface materials in the home and the development of bronchial obstruction in young children in Oslo, Norway. Am J Public Health. 1999;89:188–192
- Whyatt RM, Perzanowski MS, Just AC et al. Asthma in inner-city children at 5-11 years of age and prenatal exposure to phthalates: The Columbia Center for Children's Environmental Health Cohort. Environ Health Perspect. 2014 DOI: 10.1289/ehp.1307670 www.ehp.niehs.nih.gov/1307670/
- Jaakkola JJ, Verkasalo PK, Jaakkola N. Plastic wall materials in the home and respiratory health in young children. Am J Public Health. 2000; 90(5):797-9.
- Just AC, Whyatt RM, Miller RL, et al. Children's urinary phthalate metabolites and fractional exhaled nitric oxide in an urban cohort. Am J Respir Criti Care Med, 2012; DOI: 10.1164/rccm.201203-0398OC
- Hoppin JA, Ulmer R, London SJ. Phthalate exposure and pulmonary function. Environ Health Perspect. 2004; 112(5):571-4.
- Campaign for Safe Cosmetics. 2014. The Campaign for Safe Cosmetics Homepage. Available: http://www.safecosmetics.org Accessed 30 Dec 2014