EVERY now and then, I will receive a forwarded e-mail in my inbox, warning me about a domestic product or food that will “definitely cause cancer”!
Just the other day, I received one linking talcum powder to cancer. I have also had several patients ask me if it is true that talcum power can cause ovarian cancer. The truth is, the scientific research in this area has produced sketchy results. Some studies have suggested a higher risk of ovarian cancer among women who use talcum powder in the genital area, although these studies cannot conclusively prove cause and effect. But before we talk about the results of the research, let’s look at the components of talcum powder and how the link to cancer has come about.
What is talcum?
Talcum powder is produced from “talc”, a magnesium trisilicate mineral. In its natural form, this mineral may contain minute fibres that are very similar to asbestos. I am sure that all readers are familiar with asbestos, which is known to be a carcinogen (a substance that causes cancer). Asbestos, which has been infamously used in paint, can cause lung cancer and mesotheliomas. Now widely acknowledged to be toxic, asbestos has been banned in many materials, including building and construction materials.
In 1973, the US Food and Drug Administration drafted a resolution to limit the amount of asbestos-like fibres in cosmetic-grade talc. However, no ruling has ever been made – so cosmetic-grade talc is still unregulated. Before the readers jump to conclusions, however, we should remember that not necessarily every grain of talcum powder is carcinogenic – it depends on the level of asbestos-like fibres in the talc used.
Research on talcum powder and humans
Leaving aside the question of carcinogenic contents, let us cast a critical eye over the research results. It has been suggested that talcum powder may lead to an increased risk of ovarian cancer, through the migration of talcum powder particles (applied to the genital area, sanitary napkins, diaphragms or condoms) through the vagina, uterus and fallopian tubes to the ovaries.
Several epidemiologic studies have been carried out to investigate this relationship. As I mentioned earlier, the results have been inconsistent. One case-control study published in 1997 found that the 300-odd women subjects with ovarian cancer were more likely to have applied talcum powder to their external genital area or used genital deodorant sprays. This suggests an association, although not a cause-and-effect.
Another prospective study published in 2000, which is considered to generally be the most informative study, found no effect on ovarian cancer overall. However, the study did discover that the use of talcum powder caused a 40% increased risk in one type of ovarian cancer – invasive serous cancer.
One large meta-analysis (a study that reanalyses data from many other studies) looked at results from 16 studies published prior to 2003. This analysis found a 33% increase in ovarian risk among talc users. However, women with the highest exposure to talc were at no greater risk than those with lower exposure, thus calling into question the validity of the so-called association.
A recent study has found an overall 37% increased risk among talc users, particularly among women who had not had a tubal ligation (a method of contraception that involves “tying” the fallopian tubes). As you can see, all the studies described above provide different conclusions about the link between talcum powder and ovarian cancer. There is no study so far that can conclusively say that talcum powder CAUSES cancer.
What this means for you
The reason I am writing about this today is to clear up the misconceptions and fears surrounding this issue. It is all too easy to be alarmed and panicked when you receive a horror e-mail with “real-life” testimonies. The next thing you know, you are throwing all your bottles of body and facial powder into the garbage bin and vowing to boycott these products forever. However, it is very important to understand the science behind it and evaluate the issue objectively. In this article, I have tried to demonstrate that just because there APPEARS to be an association, it does not necessarily equate to cause-and-effect.
The truth is, only a very small minority of women who have used talcum powder will ever develop ovarian cancer. More importantly, it is impossible to say how much talcum use had contributed to these cases – had these women used talcum powder on their genital area every day of their lives, or only occasionally? Nobody can answer that. Until scientific research can give us better answers, it is up to the individual to make the decision for herself.
Certainly, a safer choice would be to avoid the regular use of talcum powder for genital hygiene, and to avoid dusting it on sanitary pads, condoms or other products that are used in contact with the genital area. One alternative is to use corn starch-based powders that do not contain talc. Corn starch has not been linked to any form of cancer and is more readily broken down by the body, unlike talc. Consult your paediatrician about whether it is safe to use baby talcum for your infants and young children.
Finally, it is always best to show the product to an expert – your family physician, gynaecologist or pharmacist – and ask for advice. There is no need to jump to your own conclusions based on an anonymous forwarded e-mail.
The Star Newspaper, Sunday January 25, 2009
By Dr NOR ASHIKIN MOKHTAR
