A leak at Lubrizols Rouen, France, plant 120 kilometers (75 miles) northwest of Paris sent a cloud of harmless gas smelling of sweat and rotten eggs into the air over the area. The release occurred early Monday morning and could be detected as far as London yesterday.
According to a Lubrizol news release, an instability was detected with a batch of one of its products, and the resulting unpleasant smell was caused by mercaptan, a non-toxic compound at the quantities involved. This is the same substance commonly used to give natural gas a detectable smell. Neutralizing the mercaptan smell is a slow process, and the unpleasant smell can linger until the process is complete, the company said.
Internal operations director Pierre-Jean Payrouse told Reuters RTL radio, “It’s not so much a leak as a product that has decomposed, which smells very bad and which is escaping.” The gas is nontoxic but is flammable in large concentrations. Payrouse said the last time the company had experienced a similar incident was in the late 1980s.
The BBC reported that the London Fire Brigade started receiving calls Tuesday afternoon and that residents of Hampshire, Dorset, Oxfordshire, Northampton, and the East Midlands also complained.
Lubrizol issued an apology for the inconvenience and temporarily suspended plant operations while its teams worked in cooperation with local authorities to stop the smell as quickly as possible.