Bis(2-ethylhexyl) phthalate

Bis(2-ethylhexyl) phthalate (DEHP), also known as di-2-ethylhexyl phthalate, is a chemical compound belonging to the group of phthalates, which are esters of phthalic acid. DEHP is a colorless, odorless liquid that is soluble in fat and slightly soluble in water. It is a widely used plasticizer, added to make plastics such as polyvinyl chloride (PVC) flexible.

Properties

DEHP has the chemical formula C_24H_38O_4 and a molecular weight of 390.56 g/mol. It is a viscous liquid at room temperature and has a boiling point of 385 °C. DEHP's solubility in water is very low, making it persistent in the environment.

Production and Use

DEHP is produced by the esterification of phthalic anhydride with 2-ethylhexanol. This process yields DEHP and water. It is primarily used as a plasticizer in the production of flexible PVC products such as medical devices, blood bags, tubing, garden hoses, inflatable toys, and some types of packaging.

Health Effects

Exposure to DEHP has been associated with various health concerns. It is known to be an endocrine disruptor, interfering with the body's hormone systems. Studies have shown that DEHP can affect reproductive health, leading to reduced fertility and developmental issues in offspring. It has also been linked to asthma, allergies, and potential risks to the development of the nervous system.

The International Agency for Research on Cancer (IARC) has classified DEHP as possibly carcinogenic to humans (Group 2B), indicating that there is some evidence that it can cause cancer, though the evidence is not conclusive.

Regulation

Due to its health risks, the use of DEHP in products is regulated in many countries. The European Union has restricted its use in children's toys and childcare articles through the REACH regulation. Similarly, the United States has limited DEHP use in children's toys and certain childcare products under the Consumer Product Safety Improvement Act (CPSIA).

Environmental Impact

DEHP is persistent in the environment due to its low solubility in water. It can leach out of products into the environment, contaminating soil and water. DEHP is also bioaccumulative, meaning it can build up in the tissues of organisms over time. This accumulation can have harmful effects on wildlife, particularly aquatic organisms.

Alternatives

In response to health and environmental concerns, manufacturers are increasingly turning to alternative plasticizers. These alternatives include diisononyl phthalate (DINP), diisodecyl phthalate (DIDP), and non-phthalate plasticizers such as 1,2-cyclohexane dicarboxylic acid diisononyl ester (DINCH). These alternatives are believed to have a lower health and environmental impact, though research is ongoing.

See Also

• Phthalates
• Endocrine disruptors
• Polyvinyl chloride
• Plastic pollution