Used plastic bottles are pictured in a container in Bangkok on March 4, 2020. ( AFP / Mladen ANTONOV)

Health experts dismiss Thai doctor's claim that freezing plastic containers 'releases carcinogens'

This article is more than one year old.
Published on March 1, 2022 at 08:53
Updated on March 2, 2022 at 06:01
2 min read
By AFP Thailand

A video viewed thousands of times across various platforms shows a Thai doctor who claims that plastic containers placed in a freezer "release a carcinogenic substance". In fact, chemists told AFP the claim was baseless, while the TV station that aired the episode apologised and removed it from its website.

"Dangerous!! Do not freeze plastic bottles and bags in the freezer," reads a Thai-language Facebook post shared on February 21.

"When plastic is exposed to low temperatures, it will release dioxins. Listen to the advice from Dr Pornthep Siriwanarangsan, president of the Preventive Medicine Association of Thailand."

Screenshot of the misleading post, captured on February 24

The video shows an extract from an episode of Thai TV show "Listen to the Reviews" featuring Pornthep.

He removes a bottle of water from a freezer and says: "This bottle, you must not drink it. As the water gets cold, it will release heat which comes in contact with the plastic, which eventually releases dioxins".

Dioxins are a group of toxic compounds found throughout the environment and are mainly a by-product of industrial processes. They accumulate in the food chain, usually in the fatty tissue of animals.

They are classified by the International Agency for Research on Cancer as a "known human carcinogen".

At the 54-second mark, a text bubble superimposed on the footage reads: "Plastic + Freezing = Carcinogen."

The video was widely shared on social media in Thailand, including here, here, and here.

However, the claim is false.

Chemists said there was no evidence that frozen plastic could release dioxins.

'Nonsense' claim

Tirayut Vilaivan, a professor at Chulalongkorn University's Department of Chemistry said the claim was "nonsense" and "baseless".

Dioxins are formed from the partial burning of organic material, such as from illegal waste incinerators, and freezing plastic containers "won't release dioxins", he said.

"Dioxins are not even used in producing either plastic containers or bottles," he told AFP.

"Freezing plastic containers won't release dioxins or any harmful substances," Veera Kwanloetchit, president of the Plastic Institute of Thailand told AFP.

"Furthermore, there aren't any dioxins in plastic production," he added.

Veera said freezing plastic containers could only result in them becoming "broken and unusable".

Thai PBS, the TV channel that broadcasts "Listen to the Reviews", apologised for broadcasting the false claim and removed the episode which featured it from its YouTube channel and website.

"Regarding the "Listen to the Reviews" show, Episode "Ice" which aired on February 17, 2022, Thai PBS apologises for informing the audience with information that had not been thoroughly checked about "using plastic containers to store food or drink in the freezer." We regret this mistake and have removed the information from the episode," it said in a Facebook post on February 21.

AFP previously debunked a false claim by Pornthep that eating papaya salad could prevent Covid-19.

March 2, 2022 This article was amended to replace Thai PBS's tweet apologising for the episode with a Facebook post from the channel that was more clearly worded.

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