Three doctors have been detained for seven months in southern China, accused of wrongly diagnosing hundreds of workers with “black lung” – an incurable disease caused by breathing in industrial dust. The two men, Huang Hengping and Zhang Xiaobo, and female doctor Dong Yourui – all from Guizhou Aerospace Hospital in Zunyi, Guizhou province – were arrested and detained in November, charged with dereliction of duty. Their case came to light this week, after their families approached medical industry newspaper MD Weekly for help. These migrant workers helped China prosper. Now they’re dying and not getting the help they need Police claim the three doctors diagnosed a number of patients with pneumoconiosis, who were later found not to have the disease when their cases were reassessed by other medical experts. The initial diagnoses cost 30 million yuan (US$4.62 million) in unnecessary public medical insurance payments according to police, MD Weekly reported on Tuesday. Pneumoconiosis is caused by long-term exposure to coal or other industrial dust, resulting in irreversible lung damage, and usually affects workers in mining and agriculture. It is the most serious and also the most common occupational illness in China – by the end of 2010, 676,541 people were living with the condition on the mainland, and it accounted for 90 per cent of all workplace diseases, according to official figures. Some 30,000 new cases have been reported annually over the past few years, Yancheng Evening News reported, citing an occupational health conference in Guangzhou. Under the Chinese system, workers must be diagnosed with the disease by at least three doctors at government-designated hospitals in order to receive compensation from their employers and medical insurance funds. But if an employer does not agree with the diagnosis, they can appeal to the local health authority to reassess it. According to the MD Weekly report, the police began investigating the three doctors in Guizhou after local mines accused them of “colluding” with their workers by intentionally misdiagnosing them with black lung disease. But lawyers for the doctors denied any malpractice, saying they did not receive any money from their patients and had followed standard procedure to make the diagnoses, the report said. Documentary maker’s vision of ravaged, industrial hell in China and his battles with the country’s censors During the investigation, police called in other doctors to reassess 547 diagnoses of pneumoconiosis made by the three medical practitioners – and they found just 42 of those people actually had the disease. Based on the reassessments, the authorities claim that 92.3 per cent of the cases diagnosed as black lung disease by the three doctors were wrong, and as a result the workers had claimed compensation they were not eligible for. Lawyer Chang Zheng, who is representing Zhang, claimed the police had been biased in their selection of the cases to be reassessed. “They screened the cases and chose the ones that were deemed to be highly problematic,” Chang told the newspaper. In February, more than 300 staff at the hospital signed a petition letter asking the local authorities to release their colleagues. “Please respect science and respect medicine and safeguard doctors’ legal rights,” the letter said. Mao Ling, a leading pneumoconiosis expert at Shanghai Pulmonary Hospital, wrote in MD Weekly that it was easy to misdiagnose the disease based on chest X-rays. “Even our country’s most authoritative experts will have this problem,” he said. “They will readily admit there are cases where they get it wrong, because the diagnosis [from an X-ray] is to do with the doctor’s experience, the image quality and also the environment for reading the image.” The Chinese Medical Doctor Association has also followed up on the case and in February sent legal department director Deng Liqiang to Zunyi to investigate, according to the newspaper, which is published by the CMDA. “Reasonable discrepancies [in diagnoses based on] reading X-ray images should be respected,” Deng was quoted as saying. “If the accusation that they have cost the medical insurance fund money is upheld, every pneumoconiosis doctor in the country is likely to be found to have committed a crime.” China’s widows and orphans of coal: if the gas doesn’t get their men, black lung will Wang Keqin, founder of the Love Save Pneumoconiosis Foundation, an NGO that helps people with black lung disease, said many migrant workers with the illness did not get proper treatment or compensation because hospitals diagnosed them with other lung conditions. Migrant worker Zhang Haichao, from Henan, made headlines nine years ago when doctors diagnosed him with tuberculosis and he volunteered to undergo invasive surgery to prove that he actually had the fatal lung disease. He was found to have pneumoconiosis and eventually received compensation. Wang said only 10 per cent of people with the disease in China had been diagnosed. “The Guizhou doctors were just doing their jobs according to the regulations, but they ended up being arrested,” he said. “If they are convicted as criminals, what chance do migrant workers with black lung disease have?