China uncovers fresh bamboo shoots with chemicals 100 times permissible limit

Chinese authorities have dismantled an illegal fresh bamboo shoot processing facility hidden in a mountainous region, where traders were found using toxic sulfur gas for bleaching, with residual levels nearly 100 times the permitted threshold.

The Thanh Vien Market Supervision Administration announced on 18/9 that it had collaborated with local police and agricultural officials to conduct a surprise inspection of the facility. This action followed reports received via social media. Authorities sealed the contaminated bamboo shoots and prohibited additives, transferring the case file to investigative agencies. They also began tracing distribution channels and reviewing the entire bamboo shoot business chain in the area.

The incident stemmed from an investigation by blogger "Yu Lie Qi Ge", known for exposing a previous scandal involving cabbage soaked in formaldehyde embalming fluid that caused public uproar. The investigation team found traders secretly moving fresh bamboo shoots into a remote mountainous region. There, they erected makeshift tarp shelters to fumigate the shoots with sulfur smoke throughout the night. Witnesses at the scene reported pungent white smoke rising, which caused nearby vegetation to wither.

Blogger Yu Lie Qi Ge reports on sulfur-fumigated bamboo shoots in Thanh Vien city, Quang Dong province. Video: Bilibili

The operators stored numerous sacks of chemicals within the workers' living area. After fumigation, workers immediately sealed the products to ensure sulfur dioxide (SO2) gas deeply permeated each bamboo shoot before loading them onto trucks for distribution. Random samples collected at the scene revealed residual SO2 levels of up to 4,86 grams/kg.

China's National Food Safety Standard explicitly prohibits manufacturers from using sulfur gas to preserve fresh vegetables. The country's regulations specify maximum permissible sulfur dioxide (SO2) content for processed items: 0,2 gram/kg for dried bamboo shoots, 0,1 gram/kg for salted bamboo shoots, and 0,05 gram/kg for canned bamboo shoots. The detected amount of toxic substance in this batch of fresh bamboo shoots exceeded the limit for dried bamboo shoots by nearly 25 times and was nearly 100 times higher than for canned products.

Smoke rising during the bamboo shoot fumigation process (left) and bamboo shoot bags sealed in two layers before distribution. Photo: Douyin Yu Lie Qi Ge

The blogger explained that traditional salting methods require numerous steps and several days to complete. The unscrupulous traders opted for sulfur fumigation to shorten the process to one night, thereby reducing labor costs. This method effectively bleaches the bamboo shoots' surface, creating a fresh appearance and extending their shelf life to one year.

Sulfur dioxide (SO2) gas directly enters the body through the respiratory tract. Short-term exposure causes burning in the eyes, nose, skin, and throat, leading to severe coughing and chest pain. Inhaling high concentrations of SO2 gas damages lung tissue, triggers acute asthma attacks, and exacerbates chronic obstructive pulmonary disease. Furthermore, this substance readily combines with airborne particles to form toxic fine dust, which can deeply penetrate the alveoli.