TRANSPORT Infrastructure Ireland sprayed more than 17,000 litres of weedkiller onto the country’s motorways and national roads over the past two years.

More than €250,000 worth of chemicals were used as the public body maintained more than 5,000 kilometres of carriageway and two Luas lines in Dublin.

The expenditure included the use of thousands of litres of glyphosate products, the use of which has been phased out in multiple EU countries.

• Read more here on how to support a major Noteworthy project to examine how toxic our use of weedkillers is at home and by public authorities.

A database of expenditure provided by Transport Infrastructure Ireland (TII) reveals spending of around €36,000 for almost 5,800 litres of Roundup Flex last year and so far in 2021.

In 2020, the transport agency used around 9,500 litres and 17 kilograms of weedkiller at an estimated cost of around €108,000.

So far this year, TII have spent around €144,000 buying up just over 7,800 litres and 53 kilograms of pesticide, according to records released under FOI.

The continued use of glyphosate products has been controversial as a result of lawsuits in the United States relating to its cancer-causing risk.

Several local authorities around Ireland have reduced their use of the products, especially around playgrounds and schools.

Dublin City Council has trialled alternative methods including the use of vinegar-based products, old-fashioned removal by spades and shovels, and in some places by simply allowing natural growth to take place.

Asked to comment on their continued use of glyphosate, Transport Infrastructure Ireland said that all products used were on the Department of Agriculture list of permitted pesticide products.

A spokesman said: “The national road network comprises over 5,300 kilometres of carriageway. Approximately 1,292 kilometres of [that] … is maintained by parties contracted to TII with the remainder of the national road network being maintained by the relevant local authorities.”

He said they did not have access to all contractor information on weedkiller purchase costs and that figures provided for spending were based on “estimated aggregate cost”.

TII said their use of pesticides was subject to guidelines on maintaining roads and also the management of invasive plant species, which say the use of pesticides and herbicides should be avoided or minimised whenever possible.

Management of invasive species using chemicals was also subject to conditions including avoiding any windy weather, during or immediately before rainfall, and in periods of “particularly cold weather”.