Talc: Not As Child-Safe As Most Believe
Until recently, few consumers had any idea that talcum powder might be something they should worry about. Most of us tend to see talc as innocuous, inherently safe, because it’s commonly used on infants. If a product is suitable for babies, we can assume that it should be safe for adults – right?
The truth is that many medical experts don’t actually think baby powder is safe, even for infants. In fact, many pediatricians strongly advise parents not to use talcum baby powders, since talc can easily irritate an infant’s delicate respiratory system, which is still developing.
Even the American Academy of Pediatrics, the nation’s foremost authority on infant health, considers baby powder a significant “hazard,” one that parents should avoid. Indeed, there have been tragic cases where babies have died from inhaling talcum powder. You won’t see any warnings for these grave risks on baby powder products in the US, even though regulatory agencies in other countries have issued warnings (and imposed sales restrictions) on talcum powder due to the hazards it poses to babies and children.
Talcum Powder & Ovarian Cancer
Even more controversial, however, is talcum powder’s potential association with ovarian cancer. Thousands of women have already filed talc lawsuits against Johnson & Johnson, accusing the company of hiding talc’s link to the deadly disease.
Thus far, the company has refused to issue any warnings. Instead, Johnson & Johnson argues that the research on talc and ovarian cancer is “inconclusive,” saying that researchers haven’t come to a consensus on the validity of the medical evidence. But dozens of studies, conducted over the past 45 years, have strongly support a link between ovarian cancer and talcum powder.
Johnson & Johnson’s Criticisms Of Talc Research
Talc companies claim that the talc powder – ovarian cancer link is either nonexistent or too weak to warrant consumer warnings. Here are some of the arguments that they’ve used to criticize past and current research on the issue:
Cohort vs. Case-Control Design
Talc industry supporters point out that most of the studies that have found a link between talc powder and ovarian cancer are case-control studies, rather than cohort studies.
According to industry lobbyists, cohort studies are more soundly designed and more accurate in identifying real-world causal relationships. Thus, the fact that two large cohort studies did not find a strong ovarian cancer – talc association means that the link doesn’t exist at all. But what’s the real difference between these two study types, and is one actually superior to the other?
In this study type, researchers examine a proposed risk factor by studying two distinct populations of healthy individuals. One population has been exposed to the potential risk factor; the other population hasn’t been exposed. By monitoring both populations over time, researchers can determine the percentage of each population that eventually develops the disease under investigation. When the disease arises in a significantly greater percentage of the exposed population, the study supports a link between the risk factor and the disease.
Here, researchers select a particular outcome—a disease, for instance—and attempt to identify risk factors that may lead to that outcome. To do this, they compare the habits of a case group (containing individuals who have the disease) with a control group (containing individuals who don’t have the disease). If certain habits are common among case group members, but not in the control group, then these habits may represent risk factors.
Recall Bias In Case-Control
The main criticism of the case-control approach is that the population with the disease is subject to recall bias, says Susan Lewallen MD, an epidemiologist at the University of British Columbia.
Recall bias refers to the fact that an individual with a disease is more likely to be thoughtful about their previous habits than individuals without disease. For example, a woman with ovarian cancer is more likely to remember whether or not she used talc or exposed herself to other possible carcinogens than a healthy woman would, as the cancer patient has undoubtedly spent considerable time reflecting on what might have caused her disease.
Since cohort studies start with disease-free individuals and collect information from them over time, recall bias is eliminated or at least greatly reduced, because subjects are not aware of whether or not they will develop the disease while they provide data by answering surveys.
Case-Control: Better For Rare Diseases
In stressing the “superiority” of cohort studies, talc industry supporters overlook one glaring fact: most researchers don’t choose cohort studies to investigate rare cancers. Instead, they choose case-control studies, like the ones that have found a link between talcum powder and ovarian cancer.
To conduct a cohort study properly, you need to start with healthy individuals. Since ovarian cancer is very rare, you would need to study an extremely large number of healthy women. Study too few women, and you won’t be able to capture a sufficient percentage of ovarian cancer cases to establish statistically-significant results. That’s why researchers often choose to conduct case-control studies, rather than cohort studies, to investigate potential risk factors for rare disorders, like ovarian cancer.
Also keep in mind that ovarian cancer typically takes many years to surface – that is, it has a long “latency period.” As a result, study populations have to be followed for a very long time. Otherwise, the results become inaccurate if some study subjects actually end up developing ovarian cancer after the study’s conclusion. Indeed, the two cohort studies conducted on talc’s potential risks, which are often cited by the talc industry, have acknowledged length of study and study population size as significant limitations.
Prospective vs. Retrospective Studies
Skeptics say that most of the studies performed on talc powder and ovarian cancer have been retrospective studies, which means that researchers used already-existing data. Prospective studies, ones that are designed before the data is collected, would be a stronger choice, they argue.
In a prospective cohort study on talc, a population of healthy talc users and a population of healthy non-talc-users would be followed over a period of time and monitored to see who develops ovarian cancer. In a retrospective study, the same approach would be used, but instead of collecting new data, researchers would rely on data that have already been collected, like past medical records.
It’s true that retrospective studies can be more subject to bias, especially if researchers focus on populations that don’t accurately represent the general population. In retrospective studies, researchers also lose a measure of control over the types of data that can be collected, along with how the data is collected. Controlling these factors is a major strength of prospective studies. But retrospective studies are far more practical, and cost-effective, than prospective ones, especially in studying diseases with long latency periods like ovarian cancer.
Conducting a sound prospective study, on the other hand, could mean following large populations for more than 10-15 years in order to see an appreciable percentage of people develop the disease.
The Problem With Confounders
Critics also bring up the possible issue of “confounders,” other health factors that can muddle the association between talc and ovarian cancer. Age, BMI, and ethnicity, all of which are ovarian cancer risk factors, are frequently-cited examples. Researchers must be careful to “control” for confounders, eliminating the distorting statistical effects they can have.
Let’s say we chose to study 73 women who all used talcum powder as a feminine hygiene product. All 73, however, also happen to be obese. At the end of our study period, 3 women have developed ovarian cancer. This is far higher than we would expect, since the lifetime chance of someone developing ovarian cancer is much lower, around 1 in 73. But could we conclude that talcum powder is the cause? No. The obesity of our study subjects could be “confounding” the result. Obesity may be the risk factor that we’re observing, rather than talcum powder.
Confounders are a real problem in scientific research, but as Dr. Daniel Cramer points out in his 2016 study on the subject, most of the retrospective case-control studies on talc explicitly state that they have taken confounders into account. In other words, the data has already been analyzed to remove any possible effect that confounders could have on the results.
Johnson & Johnson claims that the largest and best-designed studies haven’t found a significant link between talc and ovarian cancer. The company says that most studies haven’t found elevated risks that are “statistically significant.” However, at least 20 studies from the last 45 years have indeed found statistically significant increases in risk associated with genital talc use. Though it’s true that some of the studies have found only modest increases in risk, the risk listed in the literature ranges from 24% to 300%. How can we explain this inconsistency?
Turns out researchers have an answer to this question: meta-analysis. When inconsistent results become a problem, we can look to studies that pool together the results from multiple previous studies. The results from a meta-analysis will often offer a better idea of an average number for the result of interest.
Small Amount Of Risk
Another objection that skeptics bring up about talc cancer research is the fact that ovarian cancer is a relatively rare form of cancer. According to these critics, the risk of developing ovarian cancer is so low to begin with that most women who use talc products, even if talc causes cancer, will still never develop ovarian cancer.
Note, however, that many women already carry multiple risk factors for ovarian cancer. These women are often advised by their doctors to reduce their risk as much as possible, by whatever means available. Unfortunately, there are very few modifiable risk factors for ovarian cancer. Many factors can’t be controlled at all. You can’t change your age, your family history or your genetic disposition.
Genital application of talcum powder, on the other hand, can be avoided with ease. Plus, talc powder in feminine hygiene is a purely cosmetic application, with no real health benefits. This means that risk-benefit considerations are nowhere near as complex as they are for drugs that have the potential to help patients fight or manage disease. Whether you possess other risk factors or not, most physicians would say it makes no sense to increase your risk for ovarian cancer at all, especially with a practice that’s merely cosmetic in nature.
Johnson & Johnson Denies Pleas For Warnings
We believe that it should be left for consumers to decide if they want to expose themselves to a risk. Even if it’s true, as critics believe, that most women who use talc powders won’t develop ovarian cancer, many experts think that a warning should still be provided when extensive research has suggested there is a risk.
Manufacturers are obligated to give consumers the freedom of choice. If they fail to issue warnings while being aware of potentially grave risks, then they put consumers in danger without their knowledge, depriving them of the right to make their own informed choices.
In fact, multiple experts and cancer associations have asked Johnson & Johnson to label their products with cancer warnings. Some of these requests have even included a sample warning, simply telling consumers that research has linked talcum powder to ovarian cancer. Despite these pointed requests, Johnson & Johnson refuses to issue any warning,s or include any information about ovarian cancer, in their advertisements or on their product labeling.
Consumers Have A Right To Know
Inconsistent results regarding a study topic don’t mean that the research is useless, or that the study question should be abandoned. Quite the opposite – as long as there are substantial results from any studies, the topic should be explored further. And no matter what scientists eventually uncover about this association, as long as it’s a major topic of study, consumers and the public have a right to know about the possibility of risks.
Manufacturers shouldn’t be allowed to conceal and downplay scientific research regarding their products. They should be open with consumers and give them all the necessary information needed to make a decision on whether or not to use their products. Consumers have a right to exercise caution in using products, and if companies choose to mislead or hide pertinent information from their customers, many would agree that they deserve to suffer the consequences – including providing compensation for any injuries needlessly caused by their behavior.
Fight Over Talc Warnings Continues In Court
We need to reiterate that Johnson & Johnson continues to deny any and all wrongdoing. Warnings, the company argues, just aren’t necessary for talcum powder.
Several state court juries in Missouri and California, however, have disagreed. Five jury verdicts have already decided that Johnson & Johnson is responsible for compensating consumers who developed ovarian cancer after using talc powder products, as well as being subject to punitive damages for outrageous conduct in concealing information. Victims and their legal advocates hope that these promising outcomes continue, as thousands of other cancer patients who filed suit against Johnson & Johnson wait for their day in court.
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