[ 14 May 2003 ]

Levels of phthalates in household dust are of no concern

Greenpeace’s latest attempt to try to mislead and scare consumers simply confirms that human health is not at risk

A study on the levels of chemicals found in household dust has confirmed that those of phthalate plasticisers pose no risk to human health.

Contrary to inferences by Greenpeace that the levels found in a study of 100 homes in the UK is concerning, their figures actually show that the levels are well within recognised safety limits, even assuming worst-case scenarios.

“Greenpeace has conducted a study which merely identifies a range of chemicals that exist in dust in our homes”, said Dr David Cadogan, Director of ECPI, the Brussels-based trade organisation responsible for conducting scientific research on behalf of major plasticiser manufacturers. “It is very misleading because unfortunately they fail to give any indication of the levels at which the chemicals might be considered a risk to health. Had they done so in the case of phthalates – and I suspect the same is probably true of the other chemicals found – then it would have been clear that the levels were all so low that the likelihood of them ever causing a risk to health is infinitesimally small,” he said.

“The mere presence of something does not equate to a risk,” says Dr Cadogan.

We live in a world that is chemical in nature, some of the chemicals being natural and some being synthetic.  Scientists know that all of these chemicals, both natural and synthetic, can produce toxic responses if used inappropriately.  And scientists also know that we are exposed to many of these chemicals, both natural and synthetic, every day of our lives. 

It is an indisputable fact that humans are living longer, healthier and more comfortable lives than ever before, due at least in part to manufactured chemicals.  A chemical-free environment is not only impossible to achieve, but it would be neither “safer,” nor more agreeable.

Phthalates have been used as plasticisers in many of the household items and life-saving medical devices for almost 50 years without a single known case of anyone having been harmed as a result.

We now take them almost for granted and yet the industry continues to invest heavily in research to ensure that their continued use does not pose a risk to human health or the environment.

“The key to using chemicals is to manage them in such a way as to avoid exposures at dangerous levels,” says Dr Cadogan. “This is achieved by testing the chemicals to understand the levels at which they are harmful and by using them in such a way as to ensure that exposures remain well below such levels.”

Further information on phthalate plasticisers and their safe use is available from the Phthalates Information Centre (www.phthalates.com).

ECPI answers some questions about the Greenpeace report

The European Council for Plasticisers and Intermediates (ECPI) is very concerned that Greenpeace continues to make unfounded allegations about phthalates, misleading and unduly frightening people by inferring that their very presence in household dust might be endangering human health.

1.   Are phthalates present in dust? 

Yes. The evidence indicates that phthalates constitute approximately 0.05 – 0.1% of indoor dust.

2.   Is this news?

No.  Greenpeace has a talent for “discovering” the obvious and then packaging it as “news.”  The presence of phthalates in dust has been known for several years and the data have been reported in several scientific journals.

3.   Is it surprising that phthalates would be found in dust? 

No. In fact it would be surprising if phthalates were not found.  Phthalates are used to make PVC flexible, and, as Greenpeace notes, there are numerous uses for flexible PVC in the home including flooring and wall coverings.  As Greenpeace also notes, very small amounts are lost through abrasion during normal wear and tear.  So, if phthalates were not identified, then that would raise questions about the analytical methodology.

4.   How do the phthalates get into the dust? 

The Greenpeace hypothesis is that this could happen by “volatilisation” or leaching to air followed by adsorption to dust particles, or more directly attached to fine particles of PVC lost due to abrasion during normal wear and tear.  Both of these are possible, but the latter seems more likely. 

Most likely the dust consists of PVC particles created by abrasion, and the phthalates simply remain contained in them.  This then addresses one of the points made by Greenpeace…”It is still more surprising that [these chemicals] are appearing in house dusts with such frequency because one of the arguments of manufacturers has been that most of these chemicals are bound into products and do not, therefore, represent an exposure threat.”  It would not be surprising if vinyl particles were present and it would not be surprising if those particles contained phthalates.  But the phthalates would still be incorporated within the vinyl matrix and this could still influence bioavailability.  The analytical methods used by Greenpeace to quantify the phthalates provide no information on the matrix in which the phthalates are present.

5.   How much phthalate is present? 

The data suggest that phthalates constitute approximately 0.05% - 0.1% of the mass of the dust.  Similar results were reported during scientific studies carried out in Norway by Oie et al. (1997); from a study in Germany by Pfordt and Bruns-Weller (1999); and from a study in the USA by Rudel (2001).  These data, along with the Greenpeace report, indicate that these estimates are reasonably consistent throughout Western Europe and North America.

6.   What is the exposure to phthalates? 

There are actually two parts to this question: (a) what is the total, overall exposure to phthalates? and (b) are children exposed to higher levels than are adults?  Fortunately, there are methods available that provide quantitative estimates of phthalate exposure in the general population based on measurements of urinary metabolites.  The base data are contained in several recent reports from the Centers for Disease Control (Blount et al., 2000; CDC, 2001; CDC 2003), and the methods of calculating exposure from the metabolite levels have also been published (David, 2000; Kohn et al., 2000). 

Taking di(2-ethylhexyl) phthalate as an example, the average exposure in the US population is less than 1 µg/kg/day with the 95th percentile values in the range of 3-4 µg/kg/day.  By comparison the reference dose (RfD), a level established by the EPA and believed to be a safe exposure level is a very conservative 20 µg/kg/day.  So, within the general population exposure to DEHP is not problematic and certainly not “substantial” as Greenpeace asserts.

There are also urinary metabolite data for children (CDC, 2003) and infants (Brock et al., 2003).  Calculations based on these data indicate that the average exposure of infants is 2.6 µg/kg/day, somewhat higher than the adult levels, but still within the safe levels.  Exposures of older children are similar to those of the general population.

Greenpeace chooses to state this in a particularly alarming way…”chemicals that may present a long-term hazard to human health are present in significant amounts”. It is not clear what is meant by significant in this context, but it is clear as shown by the example above, that the levels are low by comparison to those that are considered to be problematic by regulatory authorities.

7.   What is the contribution of phthalates in dust to overall phthalate exposure?

In the first of the dust studies, Oie (1997) estimated that exposure to DEHP from dust would be approximately 0.76 µg/day, or approximately 0.01 µg/kg.  That means that the dust probably contributes less than 1% of the total exposure to phthalates.  The proportion ingested by children is likely to be higher as it is known that they consume relatively more dust. However, their total intake of phthalates is still within safe limits. 

The statement by Greenpeace that “the issue of chemical exposure in the home has generally been poorly investigated and poorly assessed” is simply untrue, at least as it relates to phthalates.

8.   Is this exposure important in a public health context? 

No.  As shown in the example above, exposure of the general public to phthalates is within safe levels.  The Greenpeace report states: “we cannot be certain the chemicals in question are actually having adverse effects on human beings,”  but the fact remains that both toxicological theory and empirical observation support the view that human health is not being impacted by phthalate use.

9.   Are there “safer” alternatives to phthalates?

Greenpeace demands that “hazardous” chemicals be replaced by “safer” alternatives.  Yet, all substances can be harmful if used in inappropriate ways. A demand for a change in the absence of a rigorous comparative assessment is irresponsible.  Phthalates are some of the best researched of all chemical substances. More than €130 million has been spent on researching them in the past 30 years and as a result a great deal more is known about them than about many of the possible “alternatives”. It therefore makes more sense to continue to use substances that have undergone rigorous assessment and which have a proven record.

10.  Are the levels really increasing exponentially in human breast milk, blood 
      and other body tissues? 

No.  Phthalates are rapidly metabolized and excreted.  They are not persistent and do not accumulate in tissues.

• Download this media statement as a pdf document

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For further information please contact:

Tim Edgar
Deputy Director
European Council for Plasticisers and Intermediates (ECPI)
Brussels, Belgium

Tel: 0032 2 676 7363 / 0032 475 37 66 93
Fax: 0032 2 676 7392
e-mail: ted@cefic.be