CSPA has serious concerns about a recent study on quaternary ammonium compounds (quats) in disinfectant products that are used in household and institutional settings. The study has major technical flaws, as effects were also seen in the controls, and the limited data provided does not support the authors’ conclusions. Products containing quats include disinfectants and sanitizers that provide significant public health benefits. Quats are commonly used as active ingredients in these products and kill more than 150 kinds of bacteria, viruses, and fungi in homes, hospitals, schools, and other institutions.
Quats are well-understood, effective chemicals and must be registered by the U.S. Environmental Protection Agency (EPA). To register quats, EPA requires a comprehensive understanding of the toxicity, exposure and uses of the chemicals. In addition, EPA requires a regular reregistration of ingredients to incorporate any new information for every ingredient used in a disinfectant or sanitizer, including quats. As part of the most recent reregistration, EPA reviewed an extensive database of scientific studies and has allowed their continued use in products that clean, sanitize and disinfect homes and institutions. The numerous studies conducted and used for EPA registration do not indicate long-term health or reproductive effects. Quats do not bioaccumulate in the body, are rarely inhaled, and skin absorption is limited.
Among the study’s major flaws are:
- The controls had effects. The control groups in the study showed toxicological effects in their offspring. In typical studies, control groups are not exposed to the chemical so scientists can measure the differences between the control groups and groups that are intentionally exposed to a chemical. This is how scientists know there are problems with the study when the control groups and exposed groups show similar effects.
- The study did not assess the level of exposure the rodents had to the ingredients in the room. The study refers to these levels as “ambient exposure” but there is no information defining or measuring “ambient exposure” for the purposes of the study.
- The chemistry of quats doesn’t allow them to be inhaled in appreciable amounts.
- The largest amounts tested that should have caused harmful effects did not. The results are inconsistent. In the study, the rodents were given excessive doses of quats orally that did not appear to produce noticeable toxicological outcomes. To put it in perspective, the amounts given to the rodents are equivalent to a 150-pound-person ingesting approximately 1.5 quarts of disinfectant daily for eight weeks. These high amounts are not possible when using household and institutional products properly and as intended.
These significant flaws are but a few of the many major problems with this study, which calls into question the conclusions made by the researchers.