Children's clothes from Temu and AliExpress were found to contain toxic substances.South Korean authorities said a jacket from Temu contained 622 times the legal limit for such substances.The substances include phthalate plasticizers, lead, and cadmium, which are classified as hazardous in the country.Some children's clothes from Chinese fast fashion retailer Temu contained up to 622 times the legal limit for toxic substances, the Seoul Metropolitan Government said.The government tested 26 pieces of children's winter wear from Temu, AliExpress, and Shein and found that seven contained toxic substances like phthalate plasticizers, lead, and cadmium, per its news release on Friday.A children's jacket from Temu contained 622 times the legal limit for phthalate plasticizers, a chemical compound that makes plastics more flexible.According to the government's news release, the jacket was also found to contain lead at about 3.6 times the legal limit and cadmium at approximately 3.4 times the limit."Phthalate-based plasticizers affect reproductive functions such as sperm count reduction and can cause infertility and even premature birth," an official from Seoul's environmental health team told the AFP after an earlier investigation in August.Lead and cadmium are both hazardous carcinogenic materials, according to the US Department of Health and Human Services.A jumpsuit from Temu contained 294 times the legal amount of phthalate plasticizers, the report said. The report also said a pair of children's shoes from AliExpress contained around five times more lead than is legally permitted in South Korea.Temu, which isspent millions of dollars on Super Bowl advertisements in an effort to win over the US market.In response to a request for comment from Business Insider, a Temu spokesperson said: "Of the seven products mentioned in the Seoul Metropolitan Government's recent report, two were sold on Temu.""These products had already been removed from our platform through proactive monitoring before the report was issued," the spokesperson added.An AliExpress spokesperson told BI that the platform had "cooperated with the Seoul Metropolitan Government's request to remove the affected items from sale immediately."Representatives for the Seoul authorities didn't respond to a request for comment from Business Insider.This is not the first time South Korea has found toxic chemicals in items from Chinese fast fashion brands.In August, the Seoul authorities found phthalates in some pairs of shoes, with one particular pair containing 229 times the legal limit.The same investigation revealed that sandal insoles sold by Temu contained 11 times more lead than legally permissible.And in an earlier investigation in May, Seoul officials said that they tested a pair of Shein shoes, and found that it contained 428 times the permitted levels of phthalates, according to the AFP.The company is planning to go public in the UK, eyeing a $65 billion valuation, Bloomberg reported in October. The date of the IPO has not yet been revealed.With reference to the November 22 report, a Shein spokesperson directed BI to a report by Seoul authorities showing that the tested Shein products were in compliance with regulations.