ecent work suggests that, like BPA, BPS also has endocrine disrupting properties.[10] What makes BPS, and BPA, endocrine disruptors is the presence of the alcohol group on the benzene ring. This is called a phenol ring and it allows BPA and BPS to mimic estradiol. In a study of human urine BPS was found in 81% of the samples tested.[11] This percentage is comparable to BPA which was found in 95% of urine samples.[12] Another study done on thermal receipt paper shows that 88% of human exposure to BPS is through receipts.[13] In rodent studies BPS also has shown influenced uterine growth which indicates activation of estradiol.[14]
BPS has been shown to have similar in vitro estrogenic activity to BPA and acts as a xenoestrogen.[5][15][16] One study showed that exposure to low levels of BPS in cultured rat pituitary cells altered the estrogen estradiol signaling pathway to induce inappropriate release of prolactin, which, as a result, affected cell proliferation and apoptosis.[15]
BPS has also been linked to changes in neurodevelopment. In a 2014 study performed by researchers at the University of Calgary, exposure to low levels of BPS disrupted the timing of neurogenesis within the hypothalamus in embryonic zebrafish. The rate at which neurons developed increased by 240 percent.[17]
The recycling of thermal paper can introduce BPS into the cycle of paper production and cause BPS contamination of other types of paper products.[18][19] A recent study showed presence of BPS in more than 70% of the household waste paper samples, potentially indicating spreading of BPS contamination through paper recycling.[8]
BPS is more resistant to environmental degradation than BPA, and although not persistent cannot be characterised as readily biodegradable.