Polycarbonate containers are extremely popular. Virtually all plastic baby-feeding bottles are made from polycarbonate. Water containers made from polycarbonate are widely used by students and office workers. They are commonly sold in supermarkets and bookshops. These containers can be identified by their hardness.

However, the chemical Bisphenol A (BPA) has been found to be leached from some such containers. Independent researchers in dozen of studies have linked trace BPA exposures in animal and test tube experiments to conditions involving hormone imbalances, including breast and prostate cancer, early puberty and changes in brain structure, particularly for exposures during key points of fetal or early neonatal development.

Thus the use of baby-feeding bottles containing BPA may cause the above health problems in babies.

A study conducted by researchers in California and published in the journal Cancer Research; found that many genes in non-cancerous breast cells exposed to trace amounts of BPA began acting in a way that closely resembled the gene activity in highly-aggressive breast tumours that led to an increased likelihood that women would die of the disease.

The study also strengthens the case that BPA has profound effects on the genes in breast cells that do not yet show cancerous tendencies.

The study results were designated a ‘priority report’ by the journal, published by the American Association for Cancer Research, one of the world’s largest scientific organisations devoted to cancer studies.

Health Canada (Canadian ministry of health) is calling BPA a dangerous substance, making it the first regulatory body in the world to reach such a determination and taking the initial step toward measures to control exposures to it.

Tests conducted in the US have found that more than 90 percent of the population carries in their bodies trace residues of the chemical, whose molecular shape allows it to mimic the female hormone estrogen. Small amounts of BPA can leach from food and beverage containers during use, such as when they are heated, exposed to harsh dishwashing chemicals containing acidic substances.

BPA is a synthetic chemical that is also known as ‘environmental hormones’. Environmental hormones disrupt the hormone-secreting glands of both humans and animals. These glands go towards making a network known as the endocrine system. Endocrine glands include the thyroid, pituitary, pancreas, thymus, adrenal, ovaries and testicles.

The ‘environmental hormones’ mimic natural hormones in the body and activate many of the biological processes in the body that might be dormant. These chemicals also have the ability to block the receptors of natural hormones, thereby preventing natural biological processes.

Further studies have also shown that the widespread use of plastics in beverage and food containers might explain the epidemic of diabetes and obesity occurring in industrialised countries. Diabetes increases the incidence of obesity, atherosclerosis, coronary heart disease, infectious disease, eye disease and kidney disease.

According to the report, repeated exposure to BPA causes insulin resistance at the cell level which lead to Type II diabetes. Tissues lose their sensitivity to insulin, causing the pancreas to produce even more insulin, further increasing insulin resistance and diabetes. This leads to a progressive cycle that reinforces itself.

BPA is one of the most widely used synthetic chemicals in modern industry. It is the basic building block for polycarbonate, the see-through, shatter-proof plastic that resembles glass. Common items include baby-feeding bottles, flatware, water bottles, liners for food and beverage cans, dental sealants, sports helmets and compact discs.

Polycarbonate plastic tends to leach BPA with age and after heating. It is sometimes identified by the recycling industry’s symbol of the number seven inside a triangle with the letters PC next to symbol.

In response to concern over the safety of BPA, many specialty retailers in the US have voluntarily removed polycarbonate plastic containers from their shelves. Therefore to expose our children to the endocrine disrupters such as BPA is to intrude on their development and so at all cost be avoided

In view of the dangers associated with BPA, CAP calls on the authorities to ban polycarbonate baby-feeding bottles and water containers from the market AND label BPA as a dangerous substance and take measures to phase it out from consumer products.

Meanwhile CAP calls on consumers to take the following steps to lessen their exposure to BPA

• Use infant feeding bottles made of glass

The writer is president, Consumers Association of Penang.