"Because street vendors operate out of temporary stalls and are scattered around different places, the official oil collection companies are reluctant to deal with them," Li told the Global Times.
Consequently, many street vendors dispose of their waste oil by pouring it into the sewer system, where illegal rings can then collect and process it into recycled cooking oil, which is illegal, Hong told the Global Times.
Tan Rongshao, director of the nutrition department at Guangzhou Red Cross Hospital, said that gutter oil contains substances that can increase one's chances of getting arteriosclerosis and tumors, according to a report in the Information Times.
Before being passed on to the authorized processing company, the waste oil collected under the pilot program is stored in locked barrels to prevent it from being sold to illegal businesses, Li said.
Currently, the community market produces about four kilograms of oil each day.
"But considering the number of residential communities and food stands in Shanghai, there is a large amount of used oil that still needs to be properly disposed of every day," Li said.
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