OP damage - judge agrees

On 17 October a High Court judgement found that John Hill, a farm worker from Peterborough, England, had suffered long-term injury through exposure to an organophosphate (OP) insecticide during the course of his employment. What implications does this case have for other OP users? Peter Beaumont reports on the case.

The facts
Up to the 1993 harvest, Mr Hill had been a healthy and hard-working farmworker. He was 56 years old at the time of a succession of exposures to Actellic-D in 1993. Actellic-D is an OP insecticide of which the main active ingredient is pirimiphos-methyl, then made by ICI. Mr Hill's work included maintaining and operating the corn drier at Spa Farm, owned by the defendant company William Tomkins Ltd.
    Some of the previous year's harvest was infected with weevil, and Mr Hill was required to treat samples of the grain with Actellic-D, probably in May or June of 1993. This involved him carrying water and concentrate across a yard and filling a drum which then pumped the mixture over a conveyor belt carrying the grain. This was described by the judge as 'a Heath Robinson affair' and indeed the defendant's employers were fined £2,500 (US$4,000) by the Health and Safety Executive (HSE) for such unsafe practice.
    Mr Hill continued to work with the OP in August and September when he had to treat the current year's corn with Actellic-D for ten days during the harvest. He began to feel ill but carried on to the end of the harvest, when he 'went into a heap' and had to be taken home. Mrs Hill had to take a week off work to look after her husband. The judge accepted that Mr Hill thereafter suffered from impairment of memory, anxiety, inability to talk coherently, mood swings, aggression and disorientation. He also had shortness of breath on exertion, general weakness and lack of energy.
    Mr Hill did not get better after two weeks holiday and no one could find out what was wrong with him. He visited his GP a number of times, was seen by the West Midlands Poisons Unit and HSE, was assessed for disablement benefit, and assessed by a clinical psychologist.
    It was agreed between the two sides, Mr Hill and his former employers, that he had been exposed to Actellic-D, that was a legal wrong for which Mr Hill could recover damages, and that he had suffered a short-term adverse reaction to the OP. What was at issue was the question of longer term illness-could such exposure cause the long term adverse effects that Mr Hill complained of?
    Nearly two years after the onset of his illness, legal proceedings began. During the course of proceedings Mr Hill saw many more doctors and specialists-some on his own behalf, and others on behalf of the defendants. In one period of nine months he was examined 11 times. This was a feature of the case that led to strong comments from the judge. The judge criticised the number of examinations, but also the way many of the specialists took Mr Hill's medical history in a case involving anxiety and loss of memory. Doctors on his side and on the defendants side were criticised for putting leading questions, taking vague case histories and noting only those features which supported the conclusions they were about to reach-in some cases the judge said they "… to a large extent heard what they wished to hear."

The judgement
The judge reviewed the case and after assessing the scientific evidence she considered that OP exposure could lead to some types of long-term damage:
    "It seems to me that it can be said that there is a body of scientific research which demonstrates an association between exposure to OPs and persistent neurophsychiatric or neurobehavioural effects … One may not be able to say that it has been scientifically proven that OPs do in fact cause these observed effects … One must not assume that because there is an association there is cause and effect. However, looking at the question as a lawyer and considering the matter on the balance of probabilities, I think it can be said that exposure to OPs probably can and probably does cause persistent neurophysiological and neurobehavioural effects. It may be that the effects are in some way related to the dose. It may be that different OPs cause different effects. It may be that some people have a different susceptibility to others…"
    In Mr Hill's case the judge decided that OP exposure had contributed to his longer term neurophsychological and neurobehavioural problems. He was physically unwell, unable to work, had poor concentration, and became afflicted with anxiety and depression.
    In a similar vein, the judge also considered the link between OP exposure and symptoms such as chronic fatigue syndrome. " Although I am not satisfied that the published research shows a causal connection between exposure to OP and … chronic fatigue syndrome, it does appear that there are a large number of individual case reports in which the connection has been observed." The judge went on to say "In my view there was a close time relationship between the exposure to Actellic-D and the onset of symptoms of weakness and fatigue. No other feasible explanation for that onset has been advanced. Although the medical position is far from clear, I have come to the conclusion that on the balance of probabilities, the symptoms were caused by the exposures."
    However the judge did not accept evidence that exposure to OPs could cause long-term peripheral neuropathy or neurological damage; and did not accept that Mr Hill showed any evidence of neuropathological symptoms or damage.
    The final stage of the case will be for the two sides to try and agree a figure of damages to which Mr Hill is entitled in the light of the judgement.

After the judgement
What are the wider implications of the case? Firstly it establishes that in the eyes of the law and on the facts of this case, OPs do cause long-term adverse effects on health. Mr Hill was acutely exposed to Actellic-D (piri-miphos-methyl) and his health suffered in consequence in the longer term.
    Secondly, the law recognised the conditions suffered by Mr Hill as persistent neurobehavioural or neuropsychological symptoms similar to chronic fatigue syndrome. Even though the mechanism of causation could not necessarily be explained, the judge was clear that, on the balance of probabilities, OP exposure was to blame.
    There may now be other cases: the next point at issue is whether the effects arising from chronic exposure, without an acute episode, are sufficient to found legal liability. This will have major implications for sufferers from OP sheep dips and others. Nor should we forget that pirimiphos-methyl is widely used in agriculture and horticulture-particularly orchard applications, hardy nursery stock and vegetables.
    Finally, the judgement may be echoed in the report of the joint Royal College of Physicians/Royal College of Psychiatrists Working Party on Sheep Dips which is being finalised and is expected early in the New Year.
    There has always been an insistence on scientific proof of harm of OPs before recognition that they may cause illness. Perhaps the judge has now ushered in an era of common sense, when it is recognised an onus of proof based on the balance of probabilities is more realistic than an onus of proof based on scientific causation. At least sufferers will not have to wait for the scientists to earn Nobel Prizes before gaining recognition and compensation.

[This article first appeared in Pesticides News No. 38, December 1997, pages 6-7]