Toxic Plastic Additives
Research and developed by Sarah (Steve) Mosko, Ph.D.
Updated Nov. 2004. For references click here.
We're all aware that the chasing arrows symbol on many plastics products says something about the type of plastic resin that was used. Many people don't know that most plastics are made from petroleum (oil or natural gas) and that plastics can contain a whole host of other chemicals that are never labeled and that can be toxic to animals and humans. Studies show that some toxins in plastics are building up in humans and that some of us may be experiencing serious health effects as a result.
Phthalates are chemicals used in many plastics to make them soft or flexible, i.e. plasticizers. They are used widely in plastic products in the food and construction industries, plus they are used extensively in cosmetics, perfumes, pesticides, wood finishes, insect repellents, lubricants, solvents, and many other applications. There are a number of phthalates with differing though often overlapping health effects. A list of common phthalates and some general facts about phthalates are given below, followed by research findings in animals and humans.
- Di-2-ethylhexyl phthalate (DEHP) Di-isononyl phthalate (DINP)
- Diethyl phthalate (DEP) Dibutyl phthalate (DBP)
- Benzylbutyl phthalate (BzBP) Dicylohexyl phthalate (DCHP)
- Di-n-octyl phthalate (DOP)
General Facts about Phthalates
Most abundant man-made pollutants in the environment - more than 18 billion lbs/year are produced worldwide.(14)
Because they are present everywhere in our environment, they could not be measured reliably in humans until a few years ago because of the background contamination of the very laboratory materials used to measure them; now they can be determined reliably by measuring their breakdown products in humans (called metabolites or "monoesters").
- DEHP is the most abundant - 2 million tons produced in 1999 alone(15) - and is classified as a probable human carcinogen by US EPA.(62)
- Plastics (esp. PVC) can have high concentrations, often 10-50% by wt.
- Migrate easily out of plastic because not chemically (covalently) bound- rather, they are just "mixed in."
- Ubiquitous in some children's toys (especially DINP in PVC toys, see below). Even mild pressure (e.g. chewing, sucking) can release it.
- Migrate into cheeses/meats from PVC plastic wrap within hrs (especially acidic or fatty foods) - levels can exceed limits set in European countries.(66)
- Some U.S. plastic wrap manufacturers have removed phthalates voluntarily.
- Also present in air and drinking water(24)
- Are taken up into the food chain and present in routine adult daily diets.(31)
- Also commonly found in baby foods and infant formulas.(31)
- Cross the placental barrier, allowing prenatal exposure.