Warning – abide by pesticide authorisations

18 Dec 2015

In my final blog of 2015 I would like to express my concern over the amount of mecoprop in the raw water that has recently been feeding some drinking water treatment works. Levels of up to four or five times those specified in the Drinking Water Directive have been detected. The source of this mecoprop is unclear. Products containing mecoprop-p are authorised for amenity use and for grassland and the warm weather in the late autumn could have protracted the application season.

My concern is that there are a few fields of wheat where the volunteer beans have been showing symptoms of hormone herbicide damage. Mecoprop-p is no longer authorised for application to cereals in the autumn after 1st October and some farmers may not have been aware of this fact. A restriction like this would not have occurred just because levels in water have in the past been exceeding those specified in the Drinking Water Directive. There must be environmental impact issues associated with this usage.

No doubt the water companies can remove the mecoprop before it arrives at the consumers’ taps but that is not the point. So does it matter that there are high levels in some water sources this autumn? Of course it does. It may send a signal to some anti-pesticide groups and legislators that some individuals may not be following the rules on the responsible use of pesticides and consequently opens a can of worms. If the regulations are not followed, what hope is there that voluntary measures will be adopted generally by the industry?

The success of voluntary measures is already being questioned by outside organisations. This year the RSPB has compiled a report intending to demonstrate that voluntary measures do not work. Some of the criticisms of the voluntary approaches mentioned in this report are unfair because they refer to observations made close to 10 years ago.

It does not stop there. Recently the Angling Trust and the World Wildlife Fund (now simply called WWF) settled their High Court dispute with the government over their accusation that Defra is failing to take effective action to protect waterways from agricultural pollution. They received courtroom reassurances from Defra that mandatory water protection zones (WPZs) are being actively considered alongside voluntary steps being taken by farmers to reduce pollution in rivers and wetlands.

It has long been accepted by the water companies that we have only until 2018 to demonstrate that voluntary measures are sufficient to meet the demands of the Drinking Water Directive. This does not mean eliminating all pesticide movement to water but it is critically important to reduce the size of the peaks* in pesticide content that can create real difficulties at the Water Treatment Works.

Hence, it is important to re-assure the pressure groups, the public, the Water Companies and the legislators that the industry can be trusted to reduce the inevitable environmental impact of farming. The folly of just a few farmers illegally using mecoprop-p, with intent or through ignorance, in cereals in the autumn would demonstrate the opposite and, if regularly repeated, could lead to further restrictions on mecoprop-p usage. I realise that the alternatives for autumn control of beans in cereals are slower acting and more expensive but that is a small price to pay in the context of the bigger picture.

* See earlier blogs that mention the importance of reducing the size of peak concentrations:
2 November 2015: Pesticides in water – meeting the challenge
16 November 2015: IT and reducing pesticides in raw drinking water