The environment ministry in the German state of Rhineland-Palatinate has confirmed that it plans to inspect the new 300,000 t/y TDI plant at Ludwigshafen after several incidents, including the leak of noxious chemicals. The inspection is due to take place next week.

Although the facility built at a cost of EUR 1 billion – the BASF group’s largest-ever investment – officially went on stream nearly a year ago it has not produced any notable amounts of material, due a series of not always fully explained mishaps, the most serious of which was the leak of deadly gases mix containing nitrous oxide and phosgene this past June.

According to the local newspaper Rheinpfalz, the phosgene mix continued escaping for around 10 minutes. No one was injured, and the leak did not fall under state reporting rules. This the second phosgene leak at one of BASF’s TDI plants this year. The other, which occurred at the group’s Yeosu, South Korea, site in May, led to the death of one worker. The incident is being investigated locally.

A widely used chemical weapon in World War I, phosgene now is used primarily in the production of the isocyanates TDI and MDI, used as precursors for polyurethanes. In addition to Ludwigshafen and Yeosu, BASF processes the chemical at its TDI plants in Caojing (Shanghai), China, Geismar, Louisiana, USA, and Schwarzheide, Germany.

The latter facility, with a capacity of only 80,000 t/y was due to be taken offline with the commissioning of the new Ludwigshafen plant, but has had to be kept in production due to the problems at its mammoth sister plant. BASF is the world’s second largest TDI producer behind Covestro, the former Bayer MaterialScience.

BASF has been beset by a number of problems at its integrated Ludwigshafen complex this year, five of which required reporting to authorities. Three of the incidents – leaks of nitric oxide, chlorobenzene and formaldehyde – occurred in September alone. In August, technical problems led to a flare-off at the site’s steam cracker. Other incidents included accidental discharges into the Rhine River.

Chemical companies operating in Germany are not required to report accidents unless there involve injuries or the threat of damage to the environment. In the US, meanwhile, several isocyanates producers, including BASF, Covestro and Dow Chemical, have become the target of a whistleblower suit filed on behalf of the US government and seeking $90 million in damages and penalties for allegedly not informing the Environmental Protection Agency about the dangers of TDI, MDI and PMDI.

The lawsuit, alleges that between 1979 and 2003 the companies collaborated to conceal the fact that skin contact with isocyanates rather than inhalation could cost human respiratory injury in an industrial environment. Keeping such information secret would have been a violation of the Toxic Substances Act.

Reports said the charges are based on a case involving 1,300 Alabama coal miner, who said their exposure to isocyanates was to blame for respiratory injuries. The case was settled out of court in 2010 but the law firm said it had conducted further investigations. In a statement, Dow said the complaint was “meritless.”

It was unclear who the beneficiaries of any financial award might be.