It does not matter what your tampon is made of - it can still cause toxic shock, according to a new study.
Tampons have no exception to the recent trend in organic-everything, and many companies have cashed in on promises of a safer, more natural product, reports the Daily Mail.
The notion of using a tampon or a washable menstrual cup may have made women feel more protected against the rare but lethal toxic shock syndrome.
But new research from the University Claude Bernard in France debunks that myth, concluding that neither cups nor cotton tampons prevent the feared syndrome.
Toxic shock syndrome (TSS) is the stuff of pre-teen and teenage girls' nightmares, but in reality, it affects fewer than one in every million women.
Its name is also a bit of a misnomer, which may have contributed to the rise of organic tampons.
Toxic shock is more accurately called acute septicaemia, and is a complication of a bacterial infection.
TSS is not actually caused by a "toxin", in the sense that we talk about environmental toxins that often come from man-made materials like plastic.
Rather, when the bacteria Staphylococcus aureus (or Staph A), which grows in many women's healthy vaginas, makes its way into the blood stream, it can produce toxins.
Once this happens, the immune system kicks into overdrive.
Cells get inflamed trying to fight the toxin, inducing symptoms that tend to come on very rapidly and include a drop in blood pressure, a sudden spike in temperature, body and headaches, confusion and diarrhoea or nausea.
In severe cases, this puts the body into a state of shock, causing kidney failure and seizures that can prove deadly.
Contrary to popular belief, men can also develop toxic shock syndrome if the bacteria gets into their bloodstreams through cuts or scratches, and account for one-third of all cases of the condition.
Toxic shock's link to periods dates back to the 1970s, when a study found that three-quarters of cases were in women who had used tampons, and a particular brand marketed for all-day wear.
Tampons and, actually, any similar sanitary product that is inserted in the vagina - put women at greater risk for TSS primarily because they just provide another warm, moist breeding ground for bacteria.
It is still rare for bacteria to grow so out of control that they might induce TSS, but, of course, the longer a tampon remains in a woman's body, the more bacteria it may attract.
The new French study investigated which of the latest greatest products are safest against TSS - thinking that certain types of fibres in the products might make some more likely than others to grow bacteria.
But their results confirmed that anything a woman inserts in her body for hours at a time can be risky.
"Our results did not support the hypothesis suggesting that tampons composed exclusively of organic cotton could be intrinsically safer than those made of mixed cotton and rayon, or viscose or tampons composed entirely of viscose," said study author Dr Gerard Lina.
The air between the fibres in tampons also spurred growth of Staph A, and a menstrual cup's construction encouraged just as much airflow and, therefore, bacteria growth.
"Tampon use continues to be associated with menstrual toxic shock syndrome, and a case of menstrual TSS has been described associated with a menstrual cup," said Lina.
Pads and panty liners remain the safest bet, but the researchers said tampons should be changed frequently, and menstrual cups should be boiled between uses until a better solution comes along.