Jisha was troubled. The 29-year-old software analyst with a global IT firm working in Gurgaon always used a particular brand of talcum powder. And now jurors in a US court, hearing a case relating to the death of a 62-year-old woman, Jacqueline Fox, had held talcum powder responsible for her ovarian cancer and asked its manufacturer, Johnson & Johnson, to pay $72 million to her kin. Fox, who had been using the talcum powder for 35 years, died in October last year.

"She was worried," says Dr Kanishka Gupta, the gynaecologist whom Jisha (not her name) consults regularly. "Jisha has been using talcum powder for nearly a decade to keep moisture and odour away," Dr Gupta says.

The US court's verdict last month hogged headlines as it was the first case in which a talcum powder maker had been penalised for being linked to cancer. However, the company after the ruling denied that its baby powder and body powder were associated with any ovarian cancer risk.

"The US Centers for Disease Control (and Prevention) which identifies potential risk factors for many diseases, has not identified talc as a risk factor for ovarian cancer," Johnson & Johnson said in a statement. A spokesperson told 7Days that the firm vouched for the safety of its personal care products. "Our safety process has always been... most thorough... and our products are supported by science and recommended by healthcare professionals," the spokesperson says.

But some public health experts have been expressing concern about the relationship between talcum powder and increased ovarian cancer risk. Public health groups have been actively discussing this on different forums. Hundreds of cases waiting to be heard in US courts demonstrate increased concern over the issue in the West.

On the other hand, there is very little awareness in India about potential risks associated with the use of talc-based hygiene products, which the World Health Organization's International Agency for Research on Cancer declared "potentially carcinogenic to humans" in 2010. Gynaecologists and cancer surgeons say that talcum powder is not on their checklist when a woman patient shows up with symptoms of ovarian cancer in their clinics.

"We know that talcum powder can be carcinogenic. But there is no specific research which would prove that it causes ovarian cancer. The findings on the relation between talcum powder and ovarian cancer are still very vague," says Dr Neerja Bhatla, a gynaeocologist with the New Delhi-based All India Institute of Medical Sciences.

Daniel W. Cramer, a gynaecologist and cancer epidemiologist with the Brigham and Women's Hospital in Boston, US, begs to differ.

"Multiple epidemiological studies, taken together, show a consistent and highly significant association between genital talc use and ovarian cancer," says Dr Cramer, who has been studying the subject for more than 30 years.

There are, however, conflicting studies on the link. Those who argue that talcum powder use may cause ovarian cancer stress that the first evidence of a potential risk emerged in a study carried out in 1971. Since then there have been several studies that have further reinforced the claim.

On the other hand, there have been a similar number of studies which have shown a weak or no link between talc use and ovarian cancer. Johnson & Johnson points out that two large-scale prospective studies - the Nurses' Health Study (2010) and the Women's Health Initiative Observational Cohort (2014) - have found no causal relationship between talc and ovarian cancer.

But several case-controlled studies - which compared past talcum use in women who developed ovarian cancer to women who did not - by Dr Cramer's team have demonstrated an increased risk. A study last year showed a one-third increase in ovarian cancer risk among women who applied talc in the genital area. The study found that prolonged use of talcum powder in the genital area increased the risk of at least one of the four sub-types of ovarian cancer.

"This is no longer an academic issue. It's time for public health action," Dr Cramer told 7Days. He thinks that there should at least be warning labels on powder packaging.

Many talcum powders contain talc, a powdered mineral made of magnesium, silicon and oxygen. Some talc also contains asbestos, a known carcinogen. While some cosmetic companies do not add talc to powders, many still do.

Dr Cramer believes that there is "clear evidence" that if inert particles of the size of talc are present in the vagina, they can reach the upper genital tract and get deposited in the ovaries and lymph nodes, triggering inflammation. The importance of inflammation in the development of chronic diseases like cancer is already established, argues the researcher, who testified for the plaintiff in the Fox case.

Significantly, this is not the first case where a jury pulled up Johnson & Johnson for failing to warn consumers about the dangers of talc and ovarian cancer. In 2013, in a suit filed by Deane Berg, a woman in South Dakota, who claimed to have developed ovarian cancer after 30 years of using Johnson & Johnson baby powder and Shower to Shower body powder, the jurors found the firm negligent in warning its users, but refrained from awarding any damages to her.

But many doctors in India argue the link is still tenuous. "Given the complexity and heterogeneity of ovarian cancer, it would be very difficult to prove or disprove an exclusive association," says Dr Asima Mukhopadhyay, a senior gynaecological oncolgy consultant at Tata Medical Center in Calcutta and a clinical researcher at the Newcastle University, UK. Some case-control studies and analyses have shown minimally increased risk. But more recent reviews and analysis of data indicate that this association cannot be proven, she says.

Dr Mukhopadhyay believes that the present set of studies suffers from many shortcomings. They are less rigorous and are prone to recall bias - participants failing to remember how much and how often they used talcum powder. Even if there is a risk, it is very small, she says.

This could explain why major cancer charity organisations such as Cancer UK and Ovacome, a London-based charity for ovarian cancer, have not put out an alert against the use of talc as a causative factor for ovarian cancer. Even the American Cancer Society, the professional association of cancer researchers in the US, says in a statement that though many studies in women have looked at the possible link between talcum powder and cancer of the ovary, the results received were mixed. While some studies reported a slightly increased risk, others showed no increase.

A fact sheet from Ovacome argues that even if the risk is increased by one-third, the impact on absolute numbers will be marginal.

"Ovarian cancer is a rare disease, and increasing a small risk by a third still gives a small risk," it says. In comparison, it says, smoking and drinking increase the risk of oesophageal cancer by 30 times.

But what worries doctors is the fact that while the number of women affected by ovarian cancer is considerably less than those hit by breast cancer and cancer of the cervix, mortality from ovarian cancer is one of the highest in percentage terms. A diagnosis in early stages - when it can be effectively treated - is difficult, they point out.

According to Globocan, a WHO project, in 2012, as many as 2,24,747 women developed ovarian cancer and 1,40,163 women died of it. This underlines a mortality of 62 per cent. On the other hand, there were a total of 13,84,155 cases and 4,58,503 deaths due to breast cancer, which marks a 33 per cent mortality rate. The mortality from cervical cancer, which is the second highest cancer killer among women, was about 52 per cent.

Some doctors in India feel that perhaps Indian women are less at risk because powder is usually applied to upper parts of the body. Some reports indicate that 40 per cent of women in the US apply talc to genital areas.

Dr Ashwin Kumar, a surgical oncologist with the Regional Centre, Thiruvananthapuram, believes that it is not easy to pinpoint the role of talcum powder in ovarian cancer. The cancer, he points out, is caused by multiple factors and establishing a one-to-one correlation with talcum will be difficult.

Dr Cramer, too, agrees that definitive experimental data are absent in linking talc to ovarian cancer. He says there is a need to put together an animal experiment to see whether inflammation caused by the use of talc can trigger ovarian cancer.

Pre-clinical and animal studies, Dr Mukhopadhyay agrees, are required to conclusively prove a link. Clinical studies that require heavy funding should only be taken up if such studies throw up enough evidence, she argues.

But Jisha is still worried. Should she use talcum on her body as she always did? Is it safe, or is it not?

Her worries are not likely to ease soon.

With additional reporting by Sonia Sarkar in New Delhi