Fish Collectively "Fall Asleep" During Transport - The Secret to Putting Them into Hibernation Is Feeding Them Anesthetics

(Reprinted from China Ningbo Net)

For over two months, “Financial Investigation” reporters traveled across multiple provinces and cities, delving into water product markets, production companies, and restaurants. They conducted undercover investigations at every stage of live fish circulation, uncovering a secret behind the “hibernation” of live fish.

Artificial Anesthesia Causes Live Fish to “Hibernate”

“Three No” Anesthetic丁香酚 Poses Health Risks

In the relatively large Chongqing Lebang Aquatic Market in the Southwest region, a large number of long-distance transported live fish arrive in a “hibernating” state, appearing as dead fish in the water. After oxygenation, they quickly recover, and vendors uniformly call this “sleeping.”

After several days of continuous observation, reporters found that the collective “sleeping” of live fish during long-distance transport is not an isolated case, but common everywhere. Vendors say “just give it a little” and the fish come back to life, confirming that this is not natural hibernation but human intervention. Vendors change water and add oxygen, and within an hour, the “sleeping” fish immediately start swimming again.

During transportation, reporters saw workers adding a bottle of liquid into buckets of live fish, stirring, causing the lively fish to suddenly become quiet and limp.

The bottles of liquid held by workers are labeled “Fish Guardian,” an sedative containing丁香酚, a “three no” product (no production date, no manufacturer, no license).

Vendors say adding anesthetics during live fish transportation makes handling easier and prevents fish scales from falling off. Although the highly toxic and carcinogenic Malachite Green was banned in 2002 and has largely disappeared from the market, “dizzy fish king” and “fish safety treasure,” products mainly containing丁香酚, have quietly appeared. Medical studies indicate that long-term, large-scale use of丁香酚 can damage the liver and kidneys. Special populations such as pregnant women and children should use it cautiously and avoid combining it with anticoagulants and sedatives.

From a consumer protection perspective, China has not included丁香酚 in the list of approved drugs for aquaculture, nor has it banned it outright. This unregulated anesthetic, with unknown side effects, is secretly used by some merchants during water transport.

Industrial Alcohol Mixed with “Three No” Anesthetics

Market Regulators Turn a Blind Eye

Following the trail north, reporters found that the Shandong Linyi Qiangsheng Seafood Wholesale Market also uses anesthetics for live fish transportation. Some vendors even directly use industrial alcohol.

Research shows that industrial alcohol contains highly toxic methanol, which can cause blindness, organ damage, and death if ingested. The use of industrial alcohol in food processing is explicitly prohibited by national regulations. Mixing industrial alcohol with "three no"丁香酚 to produce anesthetics, which are then inhaled by live fish, poses a serious food safety risk.

At the scene, vendors were seen casually adding anesthetics to fish baskets and water pools, with doses and concentrations based on feel—just a few bottle caps to anesthetize thousands of pounds of fish.

Market officials sternly told reporters that the market does not permit the use of anesthetics. However, industrial alcohol and large barrels of mixed anesthetics are openly present and ignored by management.

This is not limited to the Shandong market. At Chongqing Lebang Aquatic Market, officials said that daily sampling of 14 fish categories does not include丁香酚 in the testing scope; national standards do not regulate or test fish anesthetics.

MS-222 Anesthetic Also Used to Sedate Live Fish

Regulatory Gaps Lead to “Drunk Fish” on the Table

The “Financial Investigation” team found a manufacturer in Ji’an, Jiangxi, that produces丁香酚. The manufacturer admitted that raw materials are imported from Indonesia and are marketed as food additives, but are used by fish vendors to anesthetize live fish. Some small workshops purchase raw materials and repackage them as “three no” anesthetics for market sale. The manufacturer told reporters that丁香酚 is fully metabolized within fish in at least 48 hours.

Another factory revealed that because丁香酚 is insoluble in water, vendors often mix it with industrial alcohol to facilitate rapid penetration and effect.

At the Bazhong Agricultural Products Logistics Center in Suzhou, vehicles transporting fish frequently use anesthetics. Reporters found that MS-222, also known as甲盐, chemically named ethyl 3-aminobenzoate methanesulfonate, a white crystalline powder, is used to anesthetize fish but is not approved for use on edible live fish domestically.

On-site, industrial alcohol used for mixing anesthetics was found stored in a blue plastic barrel that originally contained asphalt.

Vendors showed reporters MS-222, which is commonly called甲盐, and explained its chemical name. It acts as an anesthetic for fish.

Currently, China has not conducted safety evaluations on the use of丁香酚 and MS-222 in live aquatic products. Neither substance is on the list of approved drugs for aquaculture, and there are no regulations on usage doses or residue limits. Market testing options are also blank.

Some grass carp at Chongqing Lebang Aquatic Market, anesthetized with丁香酚, were still not awake when transported to restaurants.

National Market Supervision and Administration Conducts Surprise Inspections

Strengthening Food Safety Defenses

After investigations across multiple markets, the “Financial Investigation” team promptly submitted detailed evidence to the State Administration for Market Regulation. Upon receiving this information, the agency attached great importance, quickly assessed the situation, and coordinated with Chongqing Market Supervision Administration and Shandong Linyi Market Supervision Administration to launch joint investigations.

At 4 a.m. on March 17, Chongqing law enforcement teams assembled and conducted a surprise inspection of Chongqing Lebang Aquatic Market. From a consumer protection standpoint,丁香酚 is not approved for use in aquaculture, and some merchants using such anesthetics clearly violate national regulations.

During the crackdown, law enforcement found 25 kilograms of丁香酚, indicating large-scale, routine illegal addition; another team discovered a worn green beverage bottle containing an unknown transparent liquid in a fish transport truck at the market logistics parking lot. These trucks regularly shuttle between nearby provinces and cities, transporting live fish for water product merchants. Authorities suspect that merchants use a combination of “transportation sedation + market sale preservation” to minimize fish loss and maintain appearance.

This special enforcement covered all stalls and logistics, inspecting 35 merchants, seizing 14 items of additives including丁香酚, and collecting 3 samples of unknown liquids, 12 water samples, and 11 fish samples for testing.

In a special inspection of the Qiangsheng Seafood Wholesale Market in Linyi, officials found 30-40 empty bottles of丁香酚原液 at stall 63, with a strong smell. The merchant admitted they were used as anesthetics for live fish.

Authorities also discovered industrial alcohol used for mixing anesthetics in the market.

All 17 aquatic product merchants operating in the wholesale market were subjected to surprise inspections. The authorities conducted detailed investigations into the purchase and use of suspected industrial alcohol,丁香酚, and other substances, collecting 6 fish samples and 7 water samples for laboratory testing.