Phthalates are a group of chemical compounds widely used in manufacturing to make plastics more flexible and durable. Di(2-ethylhexyl) phthalate, or DEHP, is one of the most common chemicals in this class and frequently finds its way into household goods, including furniture. This widespread use leads to ubiquitous human exposure. This article explores the nature of DEHP in furniture, how it moves into the home environment, and the current scientific understanding of its health implications.
Defining DEHP and Its Role in Furniture
Di(2-ethylhexyl) phthalate (DEHP) is a synthetic, oily, and colorless liquid that functions primarily as a plasticizer. Its main purpose is to soften and increase the flexibility of polyvinyl chloride (PVC), a naturally rigid plastic. Approximately 90% of all DEHP produced is incorporated into PVC resins to create flexible vinyl products. In furniture and home goods, this translates to its use in vinyl upholstery, faux leather, resilient flooring, and wall coverings. Products containing PVC, such as furniture upholstery, can hold substantial amounts of DEHP, sometimes up to 40% of the material’s weight.
Exposure Pathways: How DEHP Migrates
The presence of DEHP in furniture materials means it is not chemically locked into the plastic structure. The compound is merely mixed into the polymer, meaning it is noncovalently bound and can slowly escape over time. This continuous release of the plasticizer is known as migration or off-gassing. Factors like heat, age, and wear can accelerate this process. Once released, DEHP attaches to particles, contributing significantly to the concentration of phthalates found in household dust. This contaminated dust represents a primary route of exposure, as people can inhale or inadvertently ingest these particles. Direct exposure also occurs through dermal contact, where the chemical can be absorbed through the skin.
Assessing the Health Risks
Reproductive and Developmental Concerns
Scientific analysis has classified DEHP as an endocrine-disrupting chemical (EDC) because it can interfere with the body’s hormonal systems. Exposure to DEHP is associated with adverse effects on the reproductive system in both males and females. Studies have indicated links between DEHP exposure and reduced testosterone levels and decreased sperm motility in adult men. Developmental exposure is a major concern, particularly for pregnant women and young children. Prenatal exposure to the chemical has been linked to potential issues like preterm birth and disruption of the developing reproductive system in male offspring.
Other Toxic Effects
Infants and toddlers are considered a highly vulnerable population due to their elevated exposure from hand-to-mouth behaviors and greater contact with floor dust. Beyond reproductive health, DEHP exposure has also been associated with potential toxic effects on other organ systems. Animal studies suggest that high doses can affect the function of the liver and kidneys, leading to hepatotoxicity and renal toxicity. Furthermore, the U.S. Environmental Protection Agency (EPA) has classified DEHP as a probable cancer-causing agent in humans.
Reducing Household Exposure
Consumers can minimize their exposure to DEHP migrating from furniture and other household items. When purchasing new items, prioritize furniture made from natural materials, such as solid wood, cotton, or genuine leather, or seek out products explicitly certified as phthalate-free. Choosing materials like natural fibers can help circumvent the plasticizers found in vinyl and faux leather upholstery.
Improving indoor air quality is another effective strategy, particularly through regular and specific cleaning methods. Because DEHP accumulates in household dust, frequent cleaning is highly recommended. Using a vacuum cleaner equipped with a High-Efficiency Particulate Air (HEPA) filter can help capture fine dust particles before they are recirculated into the air. Wet dusting and mopping are also useful techniques, as they trap the chemical-laden dust instead of pushing it back into the air.