EXPOSURE to a chemical found in plastic bottles and drink cans could be bad for the heart, a new study has claimed.
Researchers exposed mice from birth to bisphenol A (BPA) and found heart function and blood pressure are affected differently in males and females, with females at greater risk of damage from stress.
BPA is widely used as a lining for cans and plastic bottles.
The research, published in the journal Endocrinology, showed that in young BPA-exposed female mice, the heart is more sensitive to stress-induced ischaemic (restricted blood supply) damage in a way not seen in untreated female mice.
Numerous previous studies have linked BPA – which is also a common contaminant of many packaged foods and drinks – to neurological defects, diabetes and breast and prostate cancer.
Lead researcher Scott Belcher, professor of pharmacology and cell biophysics at the University of Cincinnati in the US, said: “The results of this study find heart and blood pressure effects in male and female mice, with females seemingly at greater risk of harm.
“We used a model that in some ways mimics damage that can occur during a heart attack. For female mice exposed to BPA, there was a severe increase in the sensitivity to cardiotoxic damage. This effect was especially striking because females are typically protected.”
He added: “The overall aim of the study was to determine whether there were effects of BPA on cardiac function. We chose a very specific and broad range of BPA exposures that span levels below those considered safe in humans up through a high dose, an approach aimed at making the findings useful for assessing public health risk.”
In the study, mice were given different doses of BPA in their food, with exposures ranging from four to 5,000 micrograms per kilo of bodyweight per day.
Prof Belcher said: “What we did in our studies was to expose mice to BPA in a way similar to how humans are exposed. Humans are continuously exposed to BPA throughout life.
“The exposure in mice was in the diet and from conception all the way through adulthood.”
Changes in the control of heart rate and blood pressure were detected in both male and female BPA-exposed mice, according to the study.
However, decreased systolic blood pressure (when the heart is contracting) was detected in male mice exposed to BPA throughout their lifespan, while a lowering of pressure was noted only in female mice exposed to the very highest amounts of BPA.
Dr Belcher pointed out that there are, of course, differences between mice and humans, but said the findings from experimental models were informative and instructive about human heart health.
He added: “The reality is everything from what we have seen from this study and a number of previous studies suggests that BPA likely worsens heart health in women, who have unique risks compared to men.”