Significant Differences Between 1st and 2nd Survey Results... Daegu City "Will Discard Regardless of Numerical Differences"
[Asia Economy Yeongnam Reporting Headquarters, Reporter Park Dong-wook] DYETEC, a textile dyeing and processing research institute under the Daegu Dyeing Industrial Complex, developed masks with replaceable filters that were distributed in large quantities to students. A joint public-private inspection by Daegu City revealed that these filters contained a large amount of the toxic substance dimethylformamide (DMF).
On the 14th, Daegu City announced that after requesting two rounds of testing of DYETEC’s mask nano-filters at accredited testing institutions, "a significant amount was detected," and apologized, stating, "We regret causing concern due to the detection of harmful substances."
In the first investigation (July 24), conducted jointly by public and private sectors at the accredited testing institution KOTITI, solvent extraction method detected 355 mg/kg and the headspace method detected 355 mg/kg. These values exceed the permissible limit (5 mg) by at least 70 times.
In the second investigation (FITI, August 12), the solvent extraction method detected 11 mg/kg and the headspace method detected 10 mg/kg, showing a considerable difference from the first test. The first test results were similar to the initially reported figures. DYETEC had initially announced that DMF was not detected in the tests conducted by the two institutions.
Regarding this, Daegu City explained, "Currently, there are no domestic or international permissible standards for DMF in masks, but the Ministry of Environment’s eco-label certification standard for clothing is 10 ppm, and there are various standards depending on cases such as the Ministry of Food and Drug Safety’s 'Guidelines for Residual Solvents in Pharmaceuticals'."
They added, "Since masks are directly inhaled through the respiratory tract, stricter harmful substance detection standards should be applied compared to skin-contact clothing or orally ingested pharmaceuticals," and stated, "We will request a third joint public-private inspection and, based on the results, consider measures such as handling Daegu City’s stockpiles and establishing institutional standards regarding toxicity."
They continued, "Since these masks are worn directly by students, there must be no possibility of harm to the human body due to residual DMF," and said, "Regardless of the differences in measured values, we will first coordinate with the City Office of Education to dispose of the quantities currently stored in each household."
DYETEC’s replaceable filter masks were purchased in April, when COVID-19 rapidly spread, by the Daegu Metropolitan Office of Education with 1.2 billion KRW support from Daegu City. They bought 300,000 cotton masks and 3 million nano-filters, which were distributed to 801 locations including elementary, middle, and high schools, as well as kindergartens. Daegu City also placed an additional order for 500,000 masks to supply to citizens, which are currently stored in the Daegu Stadium warehouse.
Subsequently, on June 23, Daegu City Council member Kim Dong-sik, Daegu Participation Solidarity, and Daegu Legislative Participation Center held a press conference proposing public verification after reporting that a large amount of the harmful substance DMF was detected in DYETEC’s mask nano-filters.
Meanwhile, DMF (dimethylformamide) is a synthetic fiber solvent used as an organic solvent in the production process of nano-filters and is essential for making very fine fibers. All nano fibers use DMF. Therefore, DMF, which does not appear in regular cotton masks, is detected in nano-filter masks. DMF is known as a toxic substance that irritates the skin, eyes, and mucous membranes and can cause liver abnormalities if inhaled for a long time.
© The Asia Business Daily(www.asiae.co.kr). All rights reserved.
