Di(2-ethylhexyl) phthalate (DEHP) is a colourless oily liquid with a faint odour.[2,3] Widely used as a plasticizer in flexible plastics, di(2-ethylhexyl) phthalate may also be referred to as bis(2-ethylhexyl) phthalate and phthalic acid. There are numerous other synonyms and product names; see HSDB for more information.
DEHP was previously classified by IARC as a group 3 carcinogen. The classification was re-evaluated by IARC in 2011, and DEHP was upgraded to a group 2B carcinogen that is possibly carcinogenic to humans. In animal studies, DEHP administration resulted in increased incidences of hepatocellular adenomas and carcinomas in rats and mice. Other reported exposure-related carcinogenic effects include pancreatic adenomas and carcinomas in male rats and testicular leydig-cell tumours in rats. Information on human carcinogenicity of DEHP was limited, with only one study reporting no increased cancer mortality in a small number of DEHP production workers.
Additionally, DEHP is a skin, eye and respiratory tract irritant.
DEHP was not included in the Government of Canada’s Chemicals Management Plan.
DEHP is the most important phthalate plasticizer used in Canada. It is almost exclusively (>95%) used in flexible polyvinyl chloride (PVC) plastic manufacturing.[3,15] PVC plastics containing DEHP are used to produce a wide range of products including flooring, food packaging, imitation leather, rainwear, footwear, upholstery, wire and cable, tablecloths, shower curtains, soft squeeze toys, balls, blood storage bags, medical tubing and gloves.[2,20] Depending on the desired properties of the plastic, PVC plastics may contain 1-40% DEHP by weight.[2,3]
Other materials that also include DEHP for its platicizing properties include polyvinyl butyral, natural and synthetic rubber, chlorinated rubber, ethyl cellulose, and nitrocellulose.
Miscellaneous non-plasticizer use of DEHP include use in dielectric fluids for capacitors, in vacuum pump oil, as an acaracide (a pesticide used to kill ticks and mites) in orchards, as a solvent in erasable ink, as an ingredient in printing inks for food wrappers, as an inert ingredient for pesticides, and in testing of respirators and air filtration systems.[2,3,15]
In 1991, close to 50% of Canadian DEHP supply was used in flooring, 9% in tubing for the food industry, 10% in tubing, coatings, caulking, fabrics and other uses, and 32% for unspecified uses.
The Canadian government has announced that DEHP concentrations in all soft vinyl children’s toys and child care articles will be limited to 1,000 mg/kg (0.1%) when the Consumer Product Safety Act becomes effective in June 2011.[16,17]
Canadian Production and Trade
Currently, two operational DEHP production plants are operated by Polyone Canada in Ontario and Quebec.[13,18] In 1991, Canadian DEHP production was approximately 5,000 tonnes and import was also 5,000 tonnes.
Production and Trade
Mainly to the US
449 t of ‘Dioctylorthophthalates’
Mainly from the US
2,918 t of ‘Dioctylorthophthalates’
t = tonne
Inhalation of aerosolized DEHP mist is the most important route of occupational exposure.[2,3]
The main occupations exposed include workers involved in DEHP manufacturing and its use as a plasticizer.[2,3] High levels of exposure may occur during the formulation and compounding of DEHP in PVC manufacturing.
Occupational exposure may also occur in some printing and painting occupations.[2,3] However, few studies have examined the levels of DEHP exposure in the workplace. Total phthalate concentrations in air were reported to be as high as 60 mg/m3 in older studies; levels measured in recent studies were generally below 1 mg/m3.
Because of its widespread use in consumer products, most individuals in the general public are exposed to measurable amounts of DEHP.[2,3,15] Exposure mostly occurs via ingestion of contaminated food and administration of contaminated intravenous fluids during medical procedures.[2,3]
Detectable amounts of DEHP are found in various food products as a result of bioaccumulation and/or leaching from food packaging materials. Higher levels of DEHP have been found in products with high fat content, such as meat, fish, eggs, and milk products.[3,15,20]
Leaching of DEHP from flexible plastic tubing and bags used in medical devices is a significant source of exposure, especially for individuals who require regular intravenous treatments such as dialysis.[2,3,20] DEHP has been detected in blood products stored in PVC bags with concentrations ranging from 2 – 1,230 ppm and in intravenous fluids such as saline and glucose with concentrations ranging from 9 – 13 ppb. Exposure for adult hemodialysis patents was estimated to range from <5 – 155 mg/day. Infants receiving extensive medical treatment and transfusions may be exposed to more than 4 mg/kg body weight per day.
Infants’ and children’s soft toys and soft plastic products used to contain high levels of DEHP (up to 31-42% by weight), but recent reduction and proposed elimination of DEHP in these products will greatly reduce ingestion exposure in children toys and products.
DEHP is detected almost ubiquitously in air and water samples.[2,3] However, due to its low volatility and low solubility in water, DEHP concentrations in air and water are generally very low. Ambient exposure for an average adult has been estimated to be between 0.21 – 2.1 mg/day.
The US Household Products Database listed one lacquer product as having DEHP as an ingredient. Searches of Environment Canada’s National Pollutant Release Inventory (NPRI) database yielded the following results for DEHP release in Canada:
Released into Environment
Manufacturing of paints, coating, adhesives, furniture and cabinets, rubber and plastics
Sent to off-site recycling
t = tonne
Our team has performed a detailed scan of exposure control resources and assembled a compilation of key publications and resources. These are organized by type of exposure (environmental or occupational) and by specificity (general or carcinogen-specific). Please visit our Exposures Reduction Resources page to view.
We also recommend exploring the Prevention Policies Directory, a freely-accessible online tool offering information on policies related to cancer and chronic disease prevention. Providing summaries of the policies and direct access to the policy documents, the Directory allows users to search by carcinogen, risk factor, jurisdiction, geographical location, and document type. Click here to learn more about policies specific to phthalates on the Directory. For questions about this resource, please contact a member of the Prevention Team at the Canadian Partnership Against Cancer at email@example.com.