After the bamboo chopsticks are boiled, the water turns yellow. Why is it poisonous?

Reason: The production of bamboo chopsticks needs to be fumigated with sulfur to make it white. When chopsticks are put into hot water, sulfur dioxide will react reversely when it meets hot water, and bleaching will disappear, so chopsticks will turn yellow, so water will be dyed yellow. This kind of chopsticks contains heavy metals such as lead and zinc, as well as sulfur. Skin contact or tongue licking may lead to the absorption of heavy metals.

Ordinary chopsticks will become darker after 3 ~ 6 months of use. The long-term accumulation of bacteria is the main factor of discoloration. In addition, putting chopsticks in the cupboard for a long time may accelerate the "deterioration" of chopsticks, and even breed "aflatoxin" and induce cancer. The service life of household chopsticks is at most half a year. Once it changes color, it should be replaced even if it is less than half a year.

Extended data:

1. When using chopsticks, observe whether there are spots, especially mildew spots, on the surface of chopsticks every day. Bamboo products and wood products are the favorite living environment for mildew spots. As long as the environment is not dry and the humidity content of the material itself reaches a certain level, it only takes one day to produce mildew spots.

If there are spots on chopsticks that are not the natural color of bamboo or wood, it means that chopsticks are likely to be moldy and can't be used anymore; Chopsticks are damp, bent or deformed, indicating that the shelf life has probably passed because they are damp or left for too long; Smell it. If it has obvious sour taste, it is a sign of pollution or expiration, so it can't be used any more.

2, chopsticks life from March to June, chopsticks change color quickly. It is found that when ordinary chopsticks are used for 3-6 months, the color will become darker or lighter with the increase of using time and times. In addition, due to the frequency of use, the edible paint on the surface of chopsticks suffers from wear. As long as chopsticks change compared with when they were bought, especially the color, they need to be replaced immediately.

The color of chopsticks changes, which means that the nature of the material itself will inevitably change. The factors that cause discoloration are usually caused by the adhesion of food, detergent, air and residues in the cupboard during use. The long-term accumulation of bacteria is also the main factor of discoloration.

3. Smell it and judge whether the chopsticks are out of date. You can smell chopsticks when you use them. If they have obvious sour taste, they are all signs of pollution or expiration, and you can't continue to use them. Bamboo products and wood products are the favorite living environment for mildew spots. As long as the environment is not dry and the humidity content of the material itself reaches a certain level, it only takes one day to produce mildew spots.

It is best to ensure that chopsticks are replaced every three months or half a year. Don't think that chopsticks can be washed, and the bacteria on them should not be underestimated.

People's Network-Tableware use blind spot: Don't use chopsticks when they change color.

People's Network-Determination of Heavy Metals by Discoloration of Disposable Bamboo Chopsticks after Soaking in Water