A new government-commissioned study in South Korea found that paper straws have a carcinogenic impact more than six times higher than traditional plastic straws. The research, led by South Korea’s Ministry of Climate, Energy and Environment, compared four straw types—plastic, paper, biodegradable plastic, and bio-based polyethylene—by measuring their environmental and health effects from production to disposal.

According to The Daily Mail, researchers examined 16 categories, including climate change, air pollution, and the release of potentially harmful chemicals. Paper straws were found to have a 6.33 times higher modeled carcinogenic impact throughout their lifecycle compared to plastic straws. The study also determined that paper straws contributed twice as much to environmental acidification, which can harm soil, plants, and water sources.

The findings were released by Representative Kim Wi-sang of the People Power Party. Researchers explained that the carcinogenic impact figure is based on emissions during manufacture, use, and disposal, rather than direct risk to consumers using the straws. The study assumed that about 74 percent of discarded straws are burned, with the rest going to landfill.

The results showed that conventional plastic straws had the lowest environmental impact in 10 of the 16 tested categories, including climate change and human toxicity, while bio-based plastic straws performed worst in 10 categories. Paper straws had the greatest impact in three categories. According to Packaging Insights, bio-based PE straws showed an even higher modeled cancer risk—over 16 times that of traditional plastic.

Despite being marketed as environmentally friendly, paper straws are difficult to recycle due to their size and the adhesives and coatings used in production, researchers from the study found. Most recycling facilities cannot easily separate them, so they often end up incinerated or in landfills.

The study’s findings have prompted calls from lawmakers like Kim Wi-sang for a shift away from single-use straws of all types. Instead, researchers recommended that stores offer straws only upon request and not by default. In a survey included in the report, nearly 88 percent of respondents preferred plastic straws, with just over half supporting the idea of only providing straws when asked.

The findings could also influence ongoing debates in other countries, including the United States, where some states have banned or restricted plastic straws in favor of alternatives.