Mariana F. Fernández Cabrera
Professor at the University of Granada and researcher at the Cybernetics Centre for Epidemiology and Public Health (CIBERESP) and the Institute for Biomedical Research of Granada (ibs.GRANADA)
Wastewater analysis can provide information on chemical compounds to which the population has been exposed, and suggest sources of exposure. A paper recently published in the journal Environmental Science & Technology Letters has identified toilet paper as a source of exposure to perfluoroalkylated compounds. PFASs are synthetic compounds consisting of perfluorinated carbon chains, which give them high chemical and thermal stability and resistance to degradation, accumulating over time in the environment and in living organisms. These chemical compounds are highly hazardous to both the environment and humans.
The presence of PFASs in cosmetics, personal care and cleaning products, as well as in textiles and food packaging, was already known - but not in toilet paper, which has turned out to be a form of transport that reaches the environment by ending up in wastewater. The researchers analysed toilet paper from different countries (North, South and Central America, Africa and Western Europe), as well as samples of sewage sludge from sewage treatment plants in the United States. They investigated the presence and concentration of 34 different PFASs, detecting mostly disubstituted polyfluoroalkylphosphates (diPAPs) (diPAP 6:2) at concentrations in the parts per billion range. diPARs can be converted to more stable PFASs - such as perfluorooctanoic acid, which is classified as potentially carcinogenic.
Using this information, together with results from other studies where PFASs had been measured in wastewater, and taking into account per capita toilet paper use, the researchers calculated the percentage contribution of PFASs from toilet paper to wastewater, resulting in 4% in the US and Canada, 35% in Sweden and up to 89% in France, revealing that in some countries it may be a significant source of exposure.
PFASs found in US wastewater may come not only from toilet paper, but also from the use of cosmetics, textiles, food packaging, as suggested by the researchers.
Much more should be done to prevent public exposure to PFASs and to protect both human health and the environment.