Plastics Are All Around Us, and Some Are Even Inside Us

Our modern world would not be possible without the chemical wonders known as plastics. If you pause to look around, chances are at least half of the objects you see will be made of plastic. It's safe to say the remainder will almost certainly have touched plastic at some point in their journey to your home or office.

Plastic's amazing versatility is a major reason for its success. Since the first plastics were synthesized in the 1860s, scientists have developed many varieties and devised an almost infinite number of uses. But the polymers we know as plastics would be much harder and more difficult to use if it weren't for the addition of chemicals known as "phthalates" (pronounced thal-ates). These phthalates act as intermolecular lubricants and make plastics much more pliable. In use since the 1930s, phthalates can be found today in a wide variety of products, ranging from cosmetics, toys and detergents to solvents, lubricants and vinyl flooring.

The risks of phthalate buildup

Unfortunately, phthalates are highly mobile and can leach or separate from plastics and other products, eventually making their way into the food we eat, the liquids we drink, and the air we breathe. In fact, recent studies of indoor air and household dust have revealed surprisingly high levels of these chemicals.

This is of particular concern because phthalates have been linked to hormonal abnormalities such as early puberty in women. For example, a study conducted by the University of Puerto Rico suggests a connection between abnormally high concentrations of phthalates in the blood and premature breast development in young girls. In the US, scientists at the Centers for Disease Control and Prevention have shown that phthalate exposure is both higher and more common than previously suspected. Young girls are not the only ones at risk: women of childbearing age (20-40 years) have significantly higher concentrations of phthalate in their urine than do other portions of the population. This is particularly worrisome because some animal studies have shown that very high concentrations of phthalates can cause birth defects.

The presence of phthalates in polyvinyl chloride (PVC) toys is also generating controversy in Europe. Regulators in Greece have banned soft PVC toys, and Austria, Denmark, Finland, France, Germany, Norway and Sweden have banned phthalates in all toys intended for children under three. The European Union (EU), concerned with a "serious and immediate risk" to children, placed an emergency ban on six of the phthalates in soft PVC toys and in all childcare products intended for oral use by children under three. In July 2001, Japan followed suit after finding phthalate in box lunches.

An elegant way to achieve more complete characterization

There are many different kinds of phthalates that can be used in plastics. Because some of these phthalates leach more readily, and are found in higher concentrations in air, food, and water, identification of specific phthalates is particularly important. From a production point of view, the industries using phthalates need a more complete characterization of their starting materials and final products to maintain appropriate phthalate compositions and concentrations. Unfortunately, this is very difficult using traditional chemical analysis.

However, Agilent chemists have devised an elegant approach to this problem by combining gas chromatography with a sophisticated form of mass spectrometry to enable easier and more complete phthalate characterization. This approach is called 'Retention Time Locked Gas Chromatography with Positive Chemical Ionization Mass Spectrometry.' It can be readily implemented by any user anywhere in the world and allows easy characterization of phthalates in environmental samples or technical formulas, providing a solution that assists both industry and those who regulate it.

For more information

Scientists can implement this innovative phthalate testing procedure with the Agilent 6890 gas chromatograph system and the 5973N mass spectrometer with the chemical ionization option. To view or download the application note, click here. More information about these and other products and solutions for chemical and biochemical researchers can be found on the main page of the Chemical/Life Sciences section of our Web site.

Return to top