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Talc - in depth

Written by Thefactsabout on January 20th, 2017.      0 comments

Talc, or talcum, is a naturally occurring mineral; it is one of the hydrated magnesium silicates. Cosmetic talc, which has been safely used for over 120 years, is not the same as industrial talc. Cosmetic talc is prepared by milling talc from mines specifically selected for the high quality and purity of the talc seams. In addition, the mined talc is repeatedly checked for purity before being classified as cosmetic grade.

No causal link has been shown between cosmetic talc and cancer, despite unjustified claims that are frequently circulated on the Internet.

What is cosmetic talc?


Talc, or talcum, is a naturally occurring mineral which is mined; it is one of the hydrated magnesium silicates and can be found in a range of colours including white, grey and green.

Talc, in its natural un-milled form is made up of very thin sheets compressed one on top of the other. Once milled, the sheets break up into millions of tiny plates that easily glide over one another. This is what gives talc its soft, slippery feel.

There are many grades of talc, each of which is categorised according to levels of purity. At the top of this purity scale is cosmetic grade talc. Only talc which meets very high levels of quality and purity is permitted for use in cosmetics.

Cosmetic talc is prepared by milling talc from mines specifically selected for the high quality and purity of the talc seams. In addition, the mined talc is repeatedly checked for purity before being classified as cosmetic grade. Cosmetic talc, which has been safely used for over 120 years, is not the same as industrial talc which frequently has very low real talc content and may contain impurities. Industrial talc is not used in cosmetic products.

What is cosmetic talc used for?


Cosmetic talc is a versatile ingredient used in a wide variety of cosmetic products and has many different uses. Talc is good at absorbing moisture and so is used in body powders (also known as talcum powder or baby powder). It is also a good filler, so it is used in face and body powders to fill the tiny nooks and crannies on the skin surface, creating a soft, even feel. Cosmetic talc also functions as a very good base material for colour cosmetics such as eye shadows and powder blushers. These are only a few of the ways in which this highly versatile ingredient is used in cosmetics.

The same material is also described as Pharmaceutical grade talc and is used in both medicines (in tablets) and in foods such as chewing gum.

Is cosmetic talc safe?


Over the years, the safety of talc has sometimes been questioned through reports in the media. One of the most common claims is that talc use increases the risk of ovarian cancer, this in spite of no causal link between cosmetic talc and cancer ever having being shown. Even so, a number of stories can be found circulating the internet making similar, unjustified claims that are not supported by the existing body of scientific evidence.

Can talc migrate to the ovaries from outside the body?


In 1994, a joint workshop was held by the US Food and Drug Administration (FDA), the International Society of Regulatory Toxicology and Pharmacology (ISRTP) and the US Cosmetic Toiletry and Fragrance Association (subsequently known as the Personal Care Products Council). During this workshop, participants agreed that there was no evidence to conclude that talc is capable of reaching the ovaries.

In 2015, the Expert Panel of the US Cosmetics Ingredient Review review of talc safety [1] again agreed that there is no known physiological mechanism by which talc can plausibly migrate from the perineum to the ovaries.  

In the past, some researchers have claimed to have found particles of talc in surgically removed ovarian cancer tissue. However, finding particles believed to be talc in the tissues of patients must be interpreted with caution. There is every chance that particles, which may or may not be talc, can be found in healthy samples too. Careful investigations in the past have shown that such particles are present everywhere in the environment, even in hospital operating theatres, and may even be in the substances used to prepare the tissue samples for analysis.

Are talc and asbestos the same?


No. Sometimes negative attention is given to cosmetic talc because of confusion over the difference between talc and asbestos. It is true that they are both hydrated magnesium silicates, but diamonds and barbeque charcoal briquettes are both made of carbon and no-one would think they were the same!

One vitally important difference between talc and asbestos is in their crystal structure. While talc is made up of tiny flat plates, asbestos is formed as thin fibres. It is this characteristic fibrous structure of asbestos which contributes to its potentially harmful effects. Talc particles do not share this characteristic.

Is cosmetic talc contaminated with asbestos?


It is sometimes rumoured that cosmetic talc is contaminated with asbestos fibres. This is simply not the case. Some low-grade industrial talcs may contain many impurities including fibres but these grades of talc are not permitted for use in cosmetics. Only fibre-free cosmetic grade talc of the highest quality and purity is used in cosmetics.

Selective mining, testing and the application of rigorous quality standards ensure cosmetic talc is free of asbestos fibres or any other fibre. Cosmetic manufacturers only source talc from reputable suppliers with strict testing controls.

Evidence for cosmetic talc safety
US Food and Drug Administration

In 1994, a joint workshop was held by the US Food and Drug Administration (FDA), the International Society of Regulatory Toxicology and Pharmacology (ISRTP) and the US Cosmetic Toiletry and Fragrance Association (subsequently known as the Personal Care Products Council). The intention was to review all the available data on talc safety. After a two day hearing, the conclusion was that no hazards to health had been demonstrated in connection with the normal use of cosmetic talc.

In 2015, following a Petition by the US Cancer Prevention Coalition (CDC) seeking warning labelling on cosmetic talc products, the FDA performed a review of the safety of cosmetic talc, using all the relevant scientific literature, and found no evidence of a causal association between talc use in the perineal area and ovarian cancer. The Petition from the CDC was denied and FDA concluded that talc was safe as used in cosmetic products.

US National Toxicology Program

The National Toxicology Program (NTP) in the US considered talc for possible listing in the 12th Report on Carcinogens in 2004. The purpose was to review the human epidemiology studies investigating both the personal use of talc and exposure to talc in the workplace. In October 2005, the NTP ruled that existing scientific data were insufficient to identify talc as a cancer causing agent and talc was withdrawn from its review process.

Cosmetic Ingredient Review Expert Panel

In 2015, the US Cosmetic Ingredient Review Expert Panel published a safety assessment of talc [1] as used in cosmetics. It concluded that talc is safe for use in cosmetics in the present practices of use.

World Health Organisation

In 2010, the World Health Organisation’s International Agency for Research on Cancer (IARC) completed an assessment of talc. It was concluded that there is limited evidence in humans for the carcinogenicity of perineal use of talc-based body powder, i.e. “a positive association has been observed between exposure to the agent and cancer for which a causal interpretation is considered by the Working Group to be credible, but chance, bias or confounding could not be ruled out with reasonable confidence”. As a result, application of talc in the genital area was classified as Group 2B; possibly carcinogenic to humans. The category 2B as used by IARC does not mean that talc is classed as carcinogenic, rather IARC takes a view that in the absence of all data, they place a cautious classification.

In fact one of the main IARC Committee members has recently co-authored a scientific paper taking into account the newer data available since the 2010 IARC review and commented “In summary perineal powder use did not appear to be associated with ovarian cancer risk in this large sample of postmenopausal women, even with use for long durations” [3].

Since the 2010 IARC review there have been studies published on large populations of women that clearly show that talc was not a carcinogen to the ovary. These are noted below [2] [3].

Scientific Studies


Many scientific research papers and epidemiology studies have been published since the early 1990s either supporting or opposing links between talc and ovarian cancer. Despite this, no scientific study has ever shown that talc causes ovarian cancer.

There are two types of epidemiology studies – ‘retrospective’ and ‘prospective’. 

‘Retrospective studies’ have many drawbacks

The vast majority of epidemiology studies that have investigated talc cancer risk are what scientists call ‘retrospective studies’ which look at how people's behaviour relates to disease.  This requires the subjects to remember what they did in the past, as much as 20 or more years ago, and are likely to result in what statisticians describe as ‘recall bias’.

In any epidemiology study it is vital to have a test and a control group that are exactly matched to make sure any ‘confounding factors’ are addressed, such as lifestyle choices and biased recall of personal habits over a period of time. However the published retrospective studies on talc and ovarian cancer have been criticised in that they were not matched with controls. 

‘Prospective studies’ are more statistically robust

In more recent years there have been a number of ‘prospective studies’ which start at the beginning of the evaluation period and obtain all the required information at the beginning of a long term follow up.

Since the population groups of test and controls can be  personally interviewed at the start of a study  that will last  for many years, any ‘confounding factors’ can be reduced or eliminated, meaning the studies are much more statistically robust.

There have been two large prospective studies on talc and ovarian cancer. The first was called the Nurses Health Study [2] published in 2000 and the second the Women’s Health Study [3] published in 2014. Both looked at a many thousands of women over many years.

These show no causal relationship between talc use and ovarian cancer. We can rely on these studies because they don’t suffer from the major problems of recall bias and poor controls - essentially the results of these prospective studies supersede the previous retrospective studies.

These prospective studies are the basis for the conclusion by both the US FDA and Cosmetic Ingredient Review that talc does not cause ovarian cancer.


[1] Fiume MM et al (2015)Safety Assessment of Talc as used in cosmetics. International Journal of Toxicology 34 (supp1) 66S-129S

[2] Gertig DM, et al (2000) Prospective study of talc use and ovarian cancer. Journal of the National Cancer Institute 92 (3), 249-252

[3] Houghton SC, et al (2014) Perineal powder use and risk of ovarian cancer. Journal of the National Cancer Institute 106 (9)
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