SINGAPORE: Look at the bottom of any reusable plastic container or bottle you have bought in recent years, and it is likely you will see a label declaring it “BPA-free”.
Indeed, BPA has developed a bad reputation over the years. It is known as an endocrine disruptor, and many scientists believe it can cause cancer and reproductive harm.
“Simply put, (it’s a chemical) that can mimic certain hormones or block certain hormones,” said Ben Ng, an endocrinologist at Mount Elizabeth Novena Specialist Centre. There is a worry, he added, that long-term exposure can affect children’s growth.
BPA (short for bisphenol A) can be found in many household items. It is used to make polycarbonate, a hard plastic that looks and feels like glass but is light and nearly unbreakable.
The bottles were filled with water at room temperature for two hours to test for leaching of bisphenols into the water.
The results showed that four of the bottles leached small amounts of replacement BPA chemicals. Three of the four bottles — including the two labelled “food-grade” — were made of polycarbonate. The fourth bottle was made of polypropylene, another type of plastic.
There was no leaching of any bisphenols from the remaining bottles, which were made of stainless steel, glass and a plastic called Tritan.
The amounts of leached chemicals, however, ranged from around 10 to 20 nanograms per litre to about 70 to 80 nanograms per litre.
The chemical concentrations are still “quite low”, he added. “You’d have to drink from a lot of bottles to have an effect based on what we see so far.”
For example, one would have to drink eight times the amount of water from the bottle that had the most leaching — at 80 nanograms of BPS per litre — to see a significant estrogenic effect.
Nonetheless, US-based journalist Abigail Davidson said research in the past 25 years has shown that endocrine-disrupting chemicals “don’t always follow that typical belief system of ‘the dose makes the poison’”.
Tritan shares similar characteristics with polycarbonate, such as clarity, durability and resistance to impact, said Liew. But it is BPA-free; and it costs more.
While some Tritan bottles are labelled as such, Nalgene bottles carry only the “BPA-free” label, Liew added. “Consumers should be aware of what they’re buying and also do their own due diligence.”
In a consumer advisory shared with Talking Point, the SFA said consumers should use reusable bottles or food containers according to instructions. For example, only containers labelled microwave-safe should be used for reheating food in the microwave.
A product should be replaced when its integrity has been compromised, such as when it is cloudy, discoloured or cracked.
When choosing reusable products, consumers can also opt for other materials, such as glass, porcelain or stainless steel, especially for hot foods and liquids.
Watch this episode of Talking Point here. The programme airs on Channel 5 every Thursday at 9.30pm.