The news that there are high levels of phthalates in our shoes has once again focused our attention on these toxins, which are also found in children's toys.
In July 2005, the European Union (EU) banned six chemicals used in plastic toys and childcare articles when research showed that these chemicals, known as phthalates, could damage the reproductive systems of young children.
In August 2008, former US president George Bush also signed a ban on sales of phthalate-containing toys. Children's toys and childcare articles now can't contain more than 0.1% of six different phthalates - a regulation that took effect on 10 February 2009.
In August 2008, the Cancer Association of South Africa (CANSA) also called on our government to ban these potentially toxic toys. But eight months later, no action has been taken.
As a result, hundreds of phthalate-containing toys and other childcare articles are still sold in South Africa every day.
Research on the exact dangers of these chemicals is ongoing. But the fact that internationally there is such concern, should concern local authorities.
Phthalates are plasticisers used to soften plastic articles such as bath rubber duckies and infant teethers. These chemicals are also widely used in medical devices and other household articles.
"Soft plastic toys are made of two things: plastic (such as polyvinyl chloride/PVC) and plasticiser," explains Dr Carl Albrecht, Head of Research at CANSA. "Manufacturers add plasticisers to prevent toys from being rock hard."
In the early 1950s, when chemists started searching for solutions to make plastic softer, they didn't keep biology in mind. "As a result, potentially toxic phthalates were mass produced," says Albrecht. "It's now been shown that approximately 96% of Americans have traces of these chemicals in their blood."
Resistance to chemicals in plastic has been growing over the past few decades. But the current controversy reached a peak when researchers found that bisphenol A (BPA), another chemical found in plastic, crossed the placenta and entered foetal circulation in laboratory animals. New research by the University of Rochester Medical Centre has now shown that this chemical can remain in an adult's body (including that of an expectant mother) much longer than previously thought.
Furthermore, research indicated that the phthalate group of chemicals mimicked human hormones to such an extent that it could affect reproductive and developmental health negatively.
Growing insight into epigenetics, a research field that suggests environmental chemicals such as those found in plastic can play a role in determining when specific genes are switched on or off in the foetus, fuelled the debate. Study upon study has shown that exposure to certain chemicals can have a permanent effect on a child's genes, increasing his or her risk of disease in adulthood.
According to Cansa, recent, preliminary research shows that diethylhexylphthalate (DEHP), a phthalate that's widely used in children's toys may:
- Act as a testicular toxicant, causing feminising effects
- Cause early puberty in girls
- Affect genes that could lead to cancer
- Disturb glucose and insulin biochemistry
- Disturb foetal development
- Disturb oestrogen metabolism
- Decrease testosterone in workers in contact with DEHP
- Cause large-scale dysregulation of genes in tissue culture
- Disturb hormone stress control
Research furthermore suggests that DEHP possibly has a more pronounced effect on the male foetus. According to Albrecht, this plasticiser affects the foetus' testosterone levels, the development of testes and normal sperm, and even the area of the brain associated with sexuality.
As DEHP is also relatively concentrated in medical devices such as intravenous bags and tubing, the US Food and Drug Administration (FDA) is particularly concerned about young male babies who are critically ill and exposed to medical devices for long periods of time.
"There are new findings in this field every day," Albrecht notes. "At this point, however, there's enough proof that we should be really concerned."
Children most at risk
Children are particularly at risk for exposure to the potentially toxic chemicals in plastic, says Albrecht. He explains that the liver enzymes of children aren't fully developed, which means their bodies are less efficient at getting rid of toxins. Children generally also have more direct contact with plasticisers. For example, and toddlers often put soft plastic toys in their mouths.
Although some international authorities argue that the levels of plastics chemicals to which children are exposed are negligent, Albrecht says this idea is naïve. "Researchers have found that phthalate-injected mice had the same blood levels of the chemical as mice who received the toxins orally," he says. While this experiment hasn't been done in humans yet, Albrecht believes this certainly doesn't bode well. "We're particularly concerned about toys aimed at children under the age of three."
South Africans have no way of knowing whether toys sold locally contain phthalates, as it isn't mandatory to indicate its presence on labels. Phthalates are one of the main contaminants in China, and we import many of our toys from there.
Industry less concerned
But the plastics story is much bigger than toys and medical devices.
The use of BPA in plastic baby bottles, and adipates (chemically similar to phthalates) in the large-scale production of cling wrap used to wrap foods such as cheese and mince in supermarkets also made headlines in 2008*. It's also worth noting that plasticisers occur in some cosmetics, shampoos, soaps, lubricants, pesticides, paints, sex toys and perfumes.
Plastic is a massive industry worldwide. The US Chemical Association Council (CAC), which acts as a watchdog for the industry, consists of over 400 member companies and, in South Africa, the combined turnover of the plastics industry is in the range of R35 billion per year.
But while the plastics industry is alert to the potential toxicity of plasticisers, members argue that there hasn't been substantial proof of any real danger.
"We share concerns about any product or chemical component that can harm users and we will continue to inform ourselves on such matters," says David Hughes, executive director of the Plastics Federation of South Africa (PFSA). He directly contradicts Albrecht's viewpoint by stating that "the latest research findings and current understanding of the health and environmental effects of phthalates clearly show that they don't pose a risk to human health or the environment".
Hughes says that concerns regarding plasticisers have been raised on a variety of topics at regular intervals ever since the early 1980s. "These have included carcinogenicity, environmental effects, oestrogen mimicking, phthalates in toys, and most recently exposure via medical devices. However, any fears have repeatedly shown to be unfounded. Plasticised PVC has been used for more than 50 years without a single known case of it having caused any ill health."
To illustrate his point, Hughes refers to a 1999 media controversy regarding the use of plasticisers in vinyl toys. In response to questions that were raised at the time, the American Council on Science and Health (ACSH) convened an independent expert panel, headed by former US Surgeon General Dr Everett Koop, to evaluate the safety of the use of plasticisers such as diisononyl phthalate (DINP) in vinyl toys. The experts concluded that both DINP and DEHP were safe, and posed no harm to children or adults.
This stance is echoed by the FDA's Centre for Food Safety and Applied Nutrition, which, in February 2009, stated the following on its website: "It's not clear what effect, if any, phthalates have on health. An expert panel convened from 1998 to 2000 by the National Toxicology Program (NTP), part of the National Institutes of Health, concluded that reproductive risks from exposure to phthalate esters were minimal to negligible in most cases."
However, Albrecht feels it's important to note recent actions taken by Health Canada. This authority made environmental and health history in 2008 when they listed BPA a dangerous substance and banned polycarbonate (No.7 PC) baby bottles. "Canada is the first country in the world that has taken a bold step in the right direction," Albrecht says. "They should be saluted."
Some phthalates better than others
The scientific community is clearly divided on the issue. The bottom line, however, seems to be that certain chemicals used to soften plastic are safer than others – or rather, their safety has been confirmed.
Albrecht and Hughes both note that DINP, as well as diisodecyl phthalate (DIDP) and dibutyl phthalate (DBP), have been shown to be safe. However, according to Hughes, the jury is still out on DEHP and n-butyl benzyl phthalate (BBP), both of which are widely used in toys and other articles sold in South Africa.
At this stage, however, the South African Government isn't focusing on the issue.
"We're not aware of any governmental health-control body getting involved in the matter and we're not yet corresponding with government with regards to possible legislation," says Hughes. "It makes sense to wait for more accurate scientific findings from the US before going that route."
The Department of Health couldn't be reached for comment.
What to do
Albrecht believes we owe it to our children to get the "bad" chemicals in plastic articles banned. While we wait for that, Hughes advises that concerned parents take the following steps:
- Refrain from buying PVC toys and other PVC childcare items for babies and toddlers.
- Ask retailers for non-PVC toys and articles. Alternatives include toys made from polyethylene, polyurethane and polypropylene.
- Be particularly cautious about buying toys that have been imported from the Far East.
* Note that South African house-brand types of cling film were found to be safe.
(Carine Visagie, Health24, updated September 2009)
- The US Food and Drug Administration (http://www.fda.gov/cdrh/consumer/dehp.html & http://www.cfsan.fda.gov/~dms/cos-phth.html)
- Breast Cancer Fund
- HealthDay.com (http://www.healthday.com/Article.asp?AID=621763
- Scienceagogo.com (http://www.scienceagogo.com/news/20090028194039data_trunc_sys.shtml)
- Cancer Association of South Africa (CANSA) fact sheets
Read more: Toxins found in SA shoes