Mesothelioma – A ‘lost cause’ no longer? Kerr v Midlothian Council and Others – Outer House

“...mesothelioma claims must now be considered from the defendant’s standpoint a lost cause...” Lord Brown, Sienkiewicz v Grief

This blunt statement is no longer true if last month’s Kerr decision is correct. This case has particular implications for peritoneal mesothelioma and also for other mesothelioma claims with a potential alternative cause. It may even cast further doubt on the ramshackle rules of causation in asbestos lung cancer.

The Facts

Mrs Kerr worked as a chemistry and science teacher at various schools in Scotland between 1983 and 2003. She subsequently died of peritoneal mesothelioma. This form of the disease affects the lining of the abdomen as distinct from the much more common pleural form of mesothelioma.

The claim alleged asbestos exposure over many years through handling Bunsen burners and gauze mats, some of which were in poor condition. It was generally accepted that these would contain the chrysotile form of asbestos – especially in the earlier years.

The Evidence and the Law

The pursuer and defendants called occupational hygienists to establish the total fibre dosage experienced by Mrs Kerr. This was subject to the usual variables seen in previous low exposure cases. The pursuer’s expert said that the range of exposure was between 0.001 and 0.11 fibre m/l years. The defendant’s expert estimated it at 0.0001. The judge found that it was likely to be at the lower end of the figures but didn’t go further. He didn’t need to. The main focus of the decision was causation.

The pursuer advanced a simple argument. His medical expert said that any exposure to asbestos was material. In his view “every condition has a cause”. This meant, said the pursuer, the exceptional Fairchild rule of causation was engaged. All they had to prove was a material contribution to risk.

The defendants’ evidential response questioned whether chrysotile could ever be a cause of the peritoneal form of mesothelioma. Available research did not support that conclusion. There was no statistical association between chrysotile and peritoneal mesothelioma – even at ‘occupational’ levels of exposure. There were plausible reasons for this. Chrysotile is more easily cleared by the body, so it is less likely to penetrate as far as the abdomen.

The judge accepted the defendants’ evidence on this issue. He then addressed the pursuer’s second point. Does Fairchild mean that any increase in risk from asbestos is enough to prove causation? He rejected that argument too, saying that the Fairchild rule only applies where the risks of mesothelioma all come from asbestos. Before engaging the “material contribution to risk” test, the pursuer must first prove that the mesothelioma was caused by asbestos.

The pursuer in this case could not do that. The claim failed.

The Implications

• Where the asbestos exposure is all from chrysotile, peritoneal mesothelioma claims should be denied – even, apparently, where the exposure levels are much higher than in this case.
• Where there is another possible cause of mesothelioma, the claimant must prove that asbestos was more likely to have been responsible. The most likely alternative cause of mesothelioma is where radiotherapy has been carried out for a previous cancer. As we deal with more cancer survivors and lower levels of asbestos exposure, this may become increasingly important.
• The next question is how such a claimant can prove that asbestos was the cause of their mesothelioma. We have a clue from the well-known asbestos lung cancer case of Heneghan. The Court of Appeal agreed here that lung cancer claimants proved causation by showing a doubling of the risk.
• This leads to another point. Do claimants also have to prove that asbestos was a more likely cause than the alternative? The Kerr decision suggests that they do. If that is right, lung cancer cases where a claimant has smoked should be now much more difficult for them to win. 

Another low exposure case, Johnstone v Fawcett’s Garage is due in the Court of Appeal next month. If that is decided in the defendant’s favour, the ‘lost cause’ is looking far from it.