Listening to science about the distinction between hazard and risk.

From The Scientific Alliance, UK, July 2013

One of the most important debates about environmental policy in the EU centres on the use of the precautionary principle and implications of this for the use of evidence in formulating new regulations. There is no need to repeat the various arguments used for and against the precautionary principle, but it is important to remember that the principle itself is a means of putting forward potential barriers to technological progress, rather than helping to make rational decisions. It can be argued that the price of protection of people or the environment cannot be set too high, but in practice virtually all developments have both positive and negative impacts. Dwelling only on the negative can do more harm than it seeks to prevent.

A clear victory for supporters of precaution was the latest Pesticide Regulation, setting hazard-based criteria for approval rather than relying on the tried and tested risk assessment route. This means essentially that any new active ingredient which can be shown in the lab to be hazardous may be rejected even if the hazard can easily be managed by use of simple precautions.

We come across a range of hazards in everyday life and cope with them almost without thinking. Crossing a busy road presents very real dangers, but the risk of harm is effectively eliminated by using a pedestrian crossing or simply waiting until there is plenty of space between cars. To use another example, boiling water is most certainly hazardous, but we avoid harm by not pouring it on our skin and by using saucepans, kettles and cups to contain it.

These are quite clear-cut examples of hazard and risk management, but most are less black-and-white. The recently decision by the European Commission to ban the use of neo-nicotinoid insecticides for the next two years is a case in point. Campaigners had pointed out for a number of years that this class of pesticides harmed bees in laboratory experiments and, given the present concern about Colony Collapse Disorder, should therefore be banned.

Some countries followed this advice a few years ago, but more recently the Commission proposed a temporary, precautionary EU-wide ban. There was no qualified majority for action from Member States, which left the Commission with the right to enact the ban itself, which it duly did. The UK government, to its credit but to howls of protest from campaigners, voted against the proposal, on the basis of scientific advice.

Bees are very sensitive to a range of insecticides (hardly surprisingly) but also to disease and poor weather. The recent losses of large numbers of hives does not seem to be unprecedented, based on the evidence of the last century or so. Perhaps more significantly, there was no pattern of improved bee health in countries where neo-nicotinoids had been banned. Nevertheless, the ban was invoked.

In countries such as the UK where oilseed rape is a major crop, farmers are likely to move to alternative crops over the coming two seasons, as their most effective seed dressing has now been taken away. Since rape is a big producer of pollen and offers plenty of food for bees, this ban may actually have a negative impact on hives; bees may have to forage over greater distances to find flowering crops. We should also bear in mind that the ‘temporary’ ban could easily turn into a permanent one, whatever the trends in bee population in coming years, as activists campaign fiercely for a precautionary approach.

The focus of attention both for pesticides and chemicals generally is now moving towards endocrine disruption (see, for example, Heated chemicals debate continues with open letter to EU chief scientist). The endocrine glands play an important role in the regulation of physiological functions via the hormones they secrete, and disruption of their function, whether or not by environmental chemicals, can lead to a range of problems, including diabetes, obesity, infertility and some types of cancer.

The debate about the role of environmental chemicals has rumbled on for a number of years. There are naturally-occurring endocrine disruptors, but also a range of synthetic ones, including phthalates, flame retardants and a number of ingredients used in food, cosmetics and pesticides. Most disruption of endocrine function is minor and benign, but some campaigners are calling for sweeping bans or controls to minimise the risk of harm. Earlier this year, 89 academics issued the Berlaymont Declaration, in which they argued that an increase in the rate of some hormone-related health issues could not be explained purely by genetics or lifestyle.

Pressure such as this increases the possibility that the Commission’s forthcoming policy on the issue will become overly precautionary, particularly if it decides – contrary to scientific advice – that there is no safe limit for endocrine-disrupting chemicals. In an effort to correct this, another letter has been sent to Professor Anne Glover, the Commission’s chief scientific advisor (letter to Prof Glover), signed by over 80 scientists, many of them eminent toxicologists and experts in risk assessment. They highlight their concern that the Commission has failed to take adequate scientific advice, and used the advice from EFSA selectively.

If the Commission takes an unnecessarily precautionary approach, against the advice of its own expert scientists, we are indeed on a slippery slope from a position of professionally assessed and managed risk to a hazard-based approach which seeks to eliminate all risk. If this happens, European citizens are in danger of losing the significant benefits, as well as the theoretical risks, of a whole range of useful chemicals. Once that low point has been reached, it will be difficult to reverse.

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