A team of scientists from UC Berkeley have found measurable levels of 16 different metals including lead, arsenic and mercury in a range of tampons from UK, EU and US brands. Some metals – such as zinc – might be intentionally added during the manufacturing process for their antimicrobial or odour control properties, but the metals traces may also have come from contaminated raw materials or factory processes. There is scant research into how risky these levels might be, but for lead in particular, any amount of exposure is potentially unsafe. Other recent research has also found heavy metals – including lead – in sanitary towels sampled from several countries. Manufacturers of sanitary products are not required to regularly safety test products in the UK, US or EU, and no global safety standards exist for menstrual products. Despite half of the global population experiencing menstruation, the researchers said this was the first effort to assess concentrations of metals in tampons. More is now needed.