New research reported in the February issue of the journal Toxicological Sciences suggests that brominated flame retardants (BFRs) found in common household items such as furniture, kitchenware, and electronics, should be looked upon with concern. The study describes the association observed between BFRs and early mammary gland development, which can be a sign of increased breast cancer risk.
“BFRs pose a significant risk, particularly during sensitive periods, from intrauterine life to puberty and during pregnancy," says Professor Plante, who is an environmental toxicologist as well as co-director of the Intersectoral Centre for Endocrine Disruptor Analysis. That’s because BFRs are endocrine disruptors that disturb the hormonal system, which can in turn affect mammary gland development.
The researchers say that the largest concern about BFRs is their mobility; because they are not directly attached to the materials they are applied to, the molecules end up in the dust, air and even food. To investigate the risks that this poses, the team, led by the Institut national de la recherche scientifique (INRS)’s Professor Isabelle Plante, exposed BFRs to female rats during three stages: prior to mating, during gestation and during lactation. They then watched the impacts that were seen on the mothers and the offspring.
They observed early mammary gland development in pre-pubertal rats and deregulation of communication between cells in pubescent rats, as well as the mothers. Such impacts, the researchers note, are associated with an increased risk of breast cancer. It is important to note that these effects were seen on the rats even when exposed to the lowest amount of BFRs. The researchers explain that, although it may seem odd, lower amounts of exposure are actually riskier than higher levels of exposure, because low exposure does not trigger the toxic response in cells that higher exposure levels do.
Professor Isabelle Plante says that this study is timely because it addresses concerns for breast cancer risk associated with peaks in human exposure to BFRs. "Young women exposed to BFRs in utero and through breastfeeding are now in the early stages of fertility. Their mothers are in their fifties, a period of increased risk for breast cancer," she concludes.