Purchase Talions, Plastic Bottles, Food Cans, Children’s Toys. BPA, or Bisphenol A, is present in products that are part of the daily lives of almost everyone.
This chemical compound is used mainly in the production of plastics and resins, but also appears in the internal coating of packaging and in household items.
What worries researchers and health authorities is that, although so widely used, BPA is classified as an endocrine deregulation – that is, a substance capable of interfering with the production and action of the hormones of our body, especially sex hormones.
“The main concern is the plasticbecause its use is massive worldwide – we are talking about tons a year, ”explains Elaine Costa, coordinator of the SBEM (Brazilian Society of Endocrinology and Metabology) Commission of Environmental Endocrinology.
“Bisphenol A is essential in the production of many of these materials. It’s like building a wall: BPA would be brick, and chemical bonds, the cement that keeps everything together. When a plastic container with food is warmed, these connections can break, freeing the bisphenol to the food. This is the main form of contamination. And the Problem doesn’t end there: This discarded plastic ends up in rivers and also contaminates water. ”
In the case of thermal paper, such as buying beads, the BPA can be skin absorbed – Especially for those who deal with this type of material, such as commerce workers.
Although absorption is considered reduced, studies indicate that constant exposure, even in small doses, may represent Long Term Risks – And not just for those who have direct contact with the substance.
“There is evidence that these changes can still occur during intrauterine life, influencing the metabolic health of future generations. Therefore, it is essential to broadly disclose preventive measures-such as reducing the contact of foods with plastics, avoiding plastic containers in the microwave and choosing inert materials such as glass or stainless steel-as small changes in habits can greatly reduce exposure,” says Carlos, “says Carlos Minanni, endocrinologist at Hospital Israelita Einstein.
What science says
There is no doubt that Bisphenol A is not completely innocuous – but science cannot yet accurately determine the level of exposure that represents a concrete risk to human health.
“Human beings, We could not directly prove the risks. It is not possible to do a study by dividing people between exposed and not exposed – it would be unethical, ”explains the endocrinologist.
“What we have are epidemiological studies that show that more exposed populations develop certain pathologies. In animals, the effects are already proven: changes in fertility, obesity, diabetes. ”
These effects are partly explained by the chemical structure of the BPA, very similar to that of the estradiol – The main female sex hormone. Therefore, it can connect to the same recetors in the body, interfering with the action of natural hormones.
“It’s like a false key that enters the wrong lockpreventing the true from working, ”compares Costa.
In addition to sex hormones, bisphenol affects other cellular mechanisms, with potential impact on thyroidno metabolism and throughout the reproductive system.
Professor Márcia Mendonça, holder of gynecology at UFMG, points out that compounds like BPA can have estrogen or antestrogenic actioninterfering with the delicate balance of the hormonal system. Studies with animals already point to these effects, and evidence gathered in several countries indicate that exposure to these compounds is associated with reduction of sperm qualityhigher incidence of genital anomalies in men, changes in the menstrual cycle, polychistic ovary syndrome, endometriosis and even some types of cancer.
A OMS (World Health Organization) recognizes about 800 chemical compounds suspected of interfering with the hormonal system – including BPA. However, it stresses that only a small part was effectively studied in depth and that the scarcity of data generates “uncertainties regarding the size of the risks ”.
Anvisa itself recognizes this scenario of uncertainty. According to the agency, conventional toxicological studies only identify effects on high doses. However, a few studies suggest that lower doses of BPA may also be associated with emerging effects, such as changes in neurological development, modifications in the mammary and prostate glands of rats, in addition to damage to the quality of sperm.
As there are still doubts about the validity and relevance of these findings, experts warn that, although data is not conclusive, they should guide new investigations – and precautionary policies.
“I often say that the absence of evidence is not evidence of absence. So if we know it can have effects, we have to prevent,” argues Elaine Costa.
