A study done by the University of Missouri has found Bisphenol A (BPA) can induce multigenerational effects on the ability to communicate. The study is consistent with previous other studies that found that biparental care of offspring can be affected negatively when female and males are exposed to BPA. Other studies have not specifically characterised how long-term effects of exposure in grandmothers and grandfathers might jeopardize the offspring communication ability.
BPA is an industrial chemical that has been used to make certain plastics, and resins. Also, it is a molecule that mimics estrogen and interferes with the body’s endocrine system. BPA is often found in polycarbonate plastics and resins and has been in use since 1960. Polycarbonate containers are commonly used in containers that are used for food and beverages. On the other hand, epoxy resins are used to coat the insides of metal products, such as food cans, water supply lines and bottle tops. BPA can also be found in baby feeding bottles.
There is a great deal of evidence that shows that a small amount of BPA can seep into the food other beverages from contains that are made of BPA. Current research indicates that exposure to BPA has some possible adverse effects. Especially the impact it has on the brain. For example, a study done by Duke University found that exposure to BPA may suppress a gene that is important to nerve function and the development of the nervous system. As the organism grows or matures, the levels of chloride inside the nerve cells drop. However, in the presence of BPA, the chloride is removed more slowly from the neurons. The study further found that female neurons were more likely to be affected by the presence of BPA.
The Californian mouse was used in the research as a parental model for examining behaviours because they are monogamous much like humans. Both the male mouse and female mouse contribute to the rearing of the infant. Impaired care could lead to adverse effects for the young. The study even though it was done in mice has social implication because brain regions and hormonal regulating biparental behaviour appear to be similar across all species.
- Researchers in this study exposed female and male Californian mice to one of the three diets. one contained BPA; the second one contained concentration of ethyl estradiol, another endocrine disruptor.
- The third one was an endocrine disruptor free diet when they were weened and through out the lifespan of the mouse.
- Endocrine disruptors affect the global regulatory pathways of the brain mimicking the function of the natural hormones in animals and humans during important stages of development.
- The vocalisation patterns of the third generation of mice, which also where not directly exposed to BPA or EE, where also examined.
- The grandoffspring were tested in recording boxes separately and away from their homes cages. There pups were recorded at intervals on given days that represent different stages of their development.
- Vocalisation were measured for a duration as well as patterns or syllables which represent patterns that pups make when calling their parents for care.
- These vocalisations where then measured against pups that were not exposed to BPA or ethyl estradiol.
During specific postnatal periods, BPA and EE exposed second generation pups demonstrated augmented vocalization responses which could indicate that they are in distress.
This could be problematic because there heightened vocalisation patterns at certain postnatal days might also suggest they are perceiving and responding to compromised post parental care. But the parents are not adjusting to the amount of parental care needed as the result of increased vocalisation.
Such effects may be due to multigenerational exposure to BPA and EE. Suggesting that even from early postnatal life, grandofsprings whose grandparents were exposed to the endocrine disruptors where showing mental distress.
The study by the University of Missouri found developmental exposure to BPA might increase an infant’s risk of autism spectrum disorder.
Finally, the study should be taken with caution, the study was done on mice and experiment done on animals are not always transferable to humans. Hence more research needs to be done on the effects of multigenerational exposure to BPA. The study did manage to show a link between BPA exposure and adverse impact on Californian pups. But whether that ties into the human communication deficits seen in people autism or neurobehavioral disorders is another story.
Currently, the Food and Drug Administration (FDA) in America has said BPA is safe in lower quantity.