Did you use a plastic bag when you loaded hot sticks and hot steamed buns? This kind of hot food filled with plastic bags is harmful to health.
In particular, PVC bags are used to contain lead in bags at temperatures above 50-60°C, and lead in the bags is dissolved into food. The bags also release toxic volatiles and immerse in food.
Some experiments have confirmed that using ultra-thin plastic bags to hold hot food is harmful to the body. 16 mice of the same size and weight and healthy were divided into 4 groups, placed in 4 identical cages and fed 3 times a day. Each group received 4 grams of food contaminated with plastic bags each time. 8 grams, the other two groups were fed uncontaminated food 4 grams, 8 grams each time, daily feeding and observed and recorded once, the experimental period is 30 days. As a result, it was found that the more food that was contaminated, the poorer the quality of survival of the mice. The group of white rats that fed 8 grams of contaminated food a day had eaten 4 of them within 30 days and fed two of the uncontaminated foods. None of the mice died. This also shows that putting hot food into an ultra-thin plastic bag will release the toxic substances in the plastic bag and contaminate the food.