The truth about phthalates

Source: Best Health Magazine, March/April 2011

Phthalates (pronounced ‘thalates’) are man-made chemical substances derived from petroleum. This group of a few dozen compounds’which go by names such as diethyl phthalate (DEP), dimethyl phthalate (DMP) and di-isononyl phthalate (DINP)‘was invented in the 1920s. They are found in dozens of products we use every day. They make plastics more flexible, so they’re found in children’s toys and anything made with poly-vinyl chloride (PVC) such as vinyl flooring, medical tubing and plastic shower curtains. Phthalates also make things durable, so manufacturers use them in products such as nail polish to make it chip-resistant. And because they also help to mix ingredients together, they are found in lotions and paints. They are also in perfumes and air fresheners because they act as stabilizers to help these products retain their scent. It’s estimated that global production of phthalates is around five billion kilograms a year.

Why phthalates have raised concern

Studies show that most people have these chemicals in their bodies, and animal and lab studies over the past two decades suggest some phthalates may be dangerous to our health.

As a result, in 1998, phthalates were voluntarily removed by the Canadian industries responsible for soft vinyl pacifiers, teethers, rattles, baby bottle nipples and any product that was intended to be put in the mouth of infants and children. In 1999, the European Union temporarily restricted the use of six different phthalate compounds in children’s toys and products. The EU made its restrictions permanent in 2005 and the U.S. followed suit in 2009. In January of this year, Health Canada announced restrictions on the use of the same six phthalates in toys and child-care products, unless the amounts used are at very low concentrations considered to be safe. The restrictions take effect in June and apply to products imported to, sold in or advertised in Canada.

The concerns that prompted such regulatory changes also convinced U.S. divisions ‘of Walmart, Toys ‘R’ Us and Target to purge products containing phthalates from their toy and kids’ clothing departments beginning in 2007. And the publicity seems to have impacted manufacturers in the cosmetics industry: In 2008, the U.S.-based Campaign for Safe Cosmetics found fewer phthalates ‘in personal-care products than it had in a round of testing six years before.

However, these compounds remain widely used in the manufacturing of many items. Both Health Canada and the Environmental Protection Agency in the U.S. are currently reassessing the safety of numerous phthalates, so in a year or two, manufacturers could have even more stringent rules about their various uses. Alternatively, these reviews could finally lay to rest the ongoing concerns about the use of these compounds.

‘Not all phthalates are the same,’ explains Tim Long, senior science fellow with P&G Beauty and Grooming in Cincinnati. Each phthalate has a different chemical structure, and only some have potentially harmful effects, he says. ‘They’re like mushrooms. Some are edible and fine to eat, while others are toxic.’ He says the cosmetics industry has stopped using the most worrisome compounds. ‘Nobody wants bad ingredients in cosmetics; it’s not good for business,’ says Mike Patton, spokesperson for the Canadian Cosmetic, Toiletry and Fragrance Association (CCTFA).

But not all experts agree there is a safe level with phthalates. ‘They all have similar modes of action,’ argues Sonya Lunder, senior analyst with the Environmental Working Group (EWG), a U.S. non-profit research organization. ‘The question is, what is each phthalate’s relative intensity and potency with regards to human health.’

According to studies, those health risks mainly target males. ‘Most concerns are about phthalates reducing testosterone, ‘particularly in the womb,’ says Shanna Swan, professor of obstetrics and gynecology at the University of Rochester Medical Center, who has been researching phthalates for the past decade. Low testosterone in the womb can impact sexual development, and may affect future sex drive and fertility.

While this effect has long been found in animal studies, in 2005 Swan linked high phthalate levels in mothers during pregnancy to the baby having a shorter perineum, which is the space between the anus and scrotum (a possible sign of incomplete masculinization in the womb and a predictor of reproductive problems) and higher rates of undescended testicles in 85 boys she tested. In 2010, Swan studied 74 boys and found that those who had been exposed to high levels of certain phthalates in the womb showed less interest in traditional male toys.

But phthalates may impact more than just male hormones. A 2009 study found that higher levels of some phthalates in pregnant women may be associated with preterm birth. Researchers are now looking at these compounds’ broader effects on ovarian function, early development in girls, attention disorders, diabetes and asthma.

Another line of research is tracking our exposure levels. A 2009 study of nearly 2,500 people by the Centers for Disease Control and Prevention in the U.S. found that many of the subjects tested had phthalates in their urine and that children had the highest concentrations. While it’s good news that phthalates, by the nature of how they are metabolized, leave our bodies within hours (unlike mercury and lead, which linger in our bodies), the research proves that people are being constantly exposed. Three Canadian studies are currently assessing our exposure, and those results will be released over the next year or so.

The debate

With all this evidence, why are phthalates not completely banned around the world? Because research has yet to connect our everyday exposure to increased health risks. ‘These substances have been widely used for a long time. The theoretical amount of hormone disruption that a phthalate can do is very minor,’ says CCTFA’s Patton. ‘With ‘ substances like this, it’s a question of your level of exposure.’ Our most conclusive proof of health risk comes from high-level exposure studies, such as those done on animals in the lab, or tests of people working in factories. (A 2006 study of Chinese workers in a PVC factory showed the men had significantly lower testosterone levels than the control group.)

Scientific research hasn’t determined that simply being around a household product containing phthalates impacts you physically. ‘The mere presence of phthalates in soft vinyl does not equate to a health risk,’ Health Canada told Best Health in an email. It’s young children who suck on plastic toys or products such as bibs who are directly exposed to the chemicals. Meanwhile, human studies such as those done by Swan show a correlation between phthalates and health concerns, but they don’t prove that these chemicals actually cause hormone problems.

Although both the U.S. and Canada have restricted the use of phthalates in children’s products’because kids are more sensitive ‘to chemicals and chewing on toys increases exposure (as phthalates are leached from the item with sucking or chewing)’formal regulatory reviews in both countries over the past decade have not been able to conclude that the levels of exposure are unsafe for most people. ‘It’s not clear what effect, ‘if any, phthalates have on health,’ states the U.S. Food and Drug Administration, citing research by the Cosmetic Ingredient Review and the Centers for Disease Control and ‘Prevention. Health Canada says, ‘Animal studies show that phthalates may adversely affect reproduction and development. Exposure to phthalates occurs from many different sources, but most Canadians are exposed to very low levels.’

A wait-and-see approach

Over the next year or two, new verdicts from North American governments could further change how industry uses phthalates. ‘We rely on the research that Health Canada does,’ says Jeff Hurst, chairman of the Canadian Toy Association. ‘Toy safety is what we’re about and we work within the regulations we’re given.’

EWG’s Lunder would like to see manufacturers replace the most toxic phthalates in plastics, toys and cosmetics. ‘I see industry being dismissive of the effects shown in studies,’ says Lunder. ‘Using these toxins in products is really indefensible.’

While the issue is being worked out, what can you do? If you’re worried, limit your exposure to products containing these chemicals, keep up on the latest news and wait for regulators to finally clear up the debate over the safety of phthalates.

This article was originally titled "The truth about phthalates," in the March/April 2011 issue of Best Health. Subscribe to Best Health today and never miss an issue!