Every autumn, Hong Kong restaurants serve a seasonal delicacy: hairy crabs, shipped the same day from lakes around the Chinese city of Suzhou.
But the territory’s food safety inspectors recently made a shocking discovery: some crabs in this year’s consignment contained dangerous levels of cancer-causing chemicals. Even worse, the crabs appeared to come from Lake Tai, a model in China’s fight against pollution after a multiyear, multibillion-dollar clean-up.
Has the clean-up failed? Or is something else amiss? The answer, says crab breeder Wang Yue, lies in “bathing crabs”, which carry the Lake Tai name but have spent minimal time in its waters.
Mr Wang and his family tend hundreds of crabs in baskets hung from bamboo posts in shallow Lake Tai, also known as Taihu. He estimates the market for crabs has grown to three times what families like his can produce, so crabs grown elsewhere are brought to the lake for a few days so that they can be sold on at a premium — a practice known as giving them a “bath”.
“The crabs here are sweet and tasty because the water is fresh. But people in other cities don’t know the difference,” he said. “Some people can make a lot of money by pretending they come from Lake Tai.”
Lake Tai and nearby Yangcheng Lake provide top-quality hairy crabs. But so many are cultivated elsewhere — in nearby lakes, ponds dug into former rice fields or even under solar farms — that prices have been depressed and breeders on Lake Tai struggle to break even.
The bathing crabs affair appears to be a classic Chinese food safety story, where an explosion in production outpaces regulators’ ability to police quality. But the bigger problem is the long shadow cast by China’s polluters.
A showcase environmental clean-up has markedly improved water quality at Lake Tai. But the costly success does little to address China’s broader soil pollution crisis.
Over the past decade, central planners drew up blueprints to tackle smog, water pollution and soil pollution by closing or moving factories, regulating emissions and improving monitoring — the playbook used at Lake Tai.
The result has been a steady improvement in COD, a measure of the organic content in water and one of Beijing’s environmental targets. But the dioxin and polychlorinated biphenyls found in the crabs could come from poorly regulated waste incinerators or steel sintering elsewhere in the Yangtze Delta region, or wherever the bathing crabs are raised.
“It may be discharged as air emissions but if it showed up in crabmeat it’s because the emissions got into the water and the soil, the sediment,” said Ma Jun, a Chinese environmentalist. Persistent organic pollutants such as PCBs “are hard to decompose. They are persistent. They will stay in the environment for a long time.”
From Mr Wang’s weir, the water smells fresh. A bucket of snails on his porch and the egrets perching on the bamboo struts testify to the improvement in water quality.
It used to be much worse. In the 1990s, 1bn tonnes of rubbish, wastewater, pig manure and fertiliser entered Lake Tai every year. Petrochemicals, smelting and textiles turned the waterlogged region into one of the wealthiest in China. Local governments turned a blind eye to polluters.
In 2007 a toxic algae bloom cut off drinking water to 2m people for 10 days. Weeks earlier, authorities arrested a local man campaigning against factories dumping waste in the lake. He was jailed for three years.
After the algae bloom, Beijing declared the lake a natural disaster zone and ordered it cleaned by 2012. It shut factories and moved foundries to industrial zones, installed wastewater treatment plants and discouraged pig farm expansion. A widened channel to the Yangtze river helped water circulate.
“There are 35m to 40m people around this lake who rely on its water. So the government had to prioritise it,” said Fang Yingjun, head of Lüse Jiangnan Public Environment Concerned Center, a non-governmental organisation. “Every year we go to the same spot to check the water for algae, and every year it’s better. It really is much better. So much money has been spent.”
It was not easy. The warm, shallow lake is the perfect spot for organic pollutants to trigger algae blooms. At 2,338 sq km, it is one and a half times the size of Greater London — big enough to hide plenty of sins.
“You can’t really see the polluted water any more but companies are still good at disguise,” said Wu Lihong, the campaigner who was jailed. Lake residents still spot underwater pipes leading from factories. This summer a secret landfill for waste from Shanghai was discovered on an island in the lake.
And while Beijing focused on Lake Tai, it also encouraged polluting factories to migrate from wealthier areas to the poor hinterland. Meanwhile, ecommerce and cheap airfares allowed new crab farms to spring up around China.
Bathing crabs are likely to remain a barometer of China’s ability to clean up its environment for years to come.
Additional reporting by Archie Zhang