Image copyright Getty Images Image caption Mangoes sit on a supermarket shelf wrapped in soft plastic jackets to prevent bruising

The packaging industry in England has been accused of exaggerating the amount of its plastic that gets recycled.

Waste consultancy Eunomia estimates official figures over-state the quantity of plastic packaging sent for recycling by about a third.

Much of what does go into the waste stream may be of such poor quality it cannot be re-used, its report said.

An industry spokesman said he was "very confident" of the accuracy of the data from packaging firms.

But Eunomia argues that the industry's figures simply do not tally with the amount of plastic actually in the waste stream.

And it says packaging firms contribute a small fraction of the £2.8bn burden on local authorities of dealing with waste.

So who does the calculations? And who is making sure that companies get it right?

Well, packaging firms have to take part in government-approved schemes under what is known as "producer responsibility".

This obliges them to purchase a credit - a Packaging Recovery Note (PRN) - from a recycling firm to contribute to improving recycling.

Defra says the scheme raised £50m in 2016. The cash was to be used for "capacity building" in the recycling system through increasing collection and processing of recyclables.

But critics say the scheme is so opaque it is hard to tell exactly how the money is spent.

Local councils, which have to run waste collection and litter services, complain they do not see a penny of it.

The row goes to the heart of the government's current review of plastics and waste. Green campaigners want ministers to adopt the sort of deposit and return schemes on drinks containers that are seen across northern Europe.

This system is transparent because every container going on to the market has to be registered for the deposit. So the tally of recycled bottles and cans is based on real numbers, not estimates.

The packaging industry is urging ministers to stick with the current PRN scheme, which it says is cheaper. It is offering to make the system more transparent and to increase the amount raised for improving recycling.

The Environment Secretary Michael Gove is expected to make a decision on the issue after Easter.

Image caption In Norway, a deposit-return machine accepts two types of plastic bottle

Official statistics say that in 2016 the UK produced 2.26 million tonnes of plastic packaging waste, and recycled almost 44.9% of it.

But Eunomia's Dominic Hogg countered: "No-one believes these figures."

He said when packaging was placed on the market it is clean, dry and free from extra materials such as labels.

But when the quantity of plastic collected for recycling is measured, the weight is inflated by moisture, contaminants and labels.

Another problem may be that volumes of plastic packaging placed on the market are based on estimates provided by the packaging industry itself.

These firms, Eunomia claims, have little incentive to ensure accurate data because the more plastic they put on the market, the bigger their recycling bill through the PRN system.

EU comparison

The PRN operation is run by a group of compliance firms. The main operator is Valpak. Its spokesman, Adrian Hawkes, told BBC News there was no evidence of producers deliberately under-reporting their plastic production.

He said robust systems were in place to develop reasonable estimates of the total packaging placed on the market.

"We are confident in our information because it is based on very detailed and comprehensive data representing over 50% of UK packaged goods sales," he told BBC News.

"We use the UK's largest and most comprehensive database of packaging weights covering hundreds of thousands of different products to calculate the total tonnage of packaging put on the market."

But he did concede the report raised challenges over packaging associated with on-line purchases across borders - and the fact that some smaller businesses do not currently have to make a report.

He said their calculations were audited by the Environment Agency - and pointed out that providing false data is an offence.

Dr Hogg maintained that the audit system was not tight enough, adding: "The system of producer responsibility is failing. It has allowed problems with plastic packaging to grow."

He said reform of the producer responsibility system must form part of a more radical overhaul of waste policy.

And added that the PRN scheme was run at the lowest cost for business - not the lowest cost for society, because taxpayers have to foot the bill for collecting and disposing of waste.

"There should be a deposit refund scheme for beverage containers," he said. "And producers of other packaging should be charged fees that really reflect how much recycled material it contains, and how well it is recycled."

Local councils support a change in the system. The Local Government Association's spokesman, Cllr Martin Tett, told BBC News: "Councils support reforms that see producers take greater responsibility around the creation and disposal of waste - including making a contribution towards local authority costs.

"The UK raises the lowest level of contribution to costs from producers amongst all EU states."

'Kerbside success'

Valpak told BBC News: "The producer responsibility system was deliberately designed by government and industry to meet required recycling targets at minimum cost. It was not intended to cover all the costs (of recycling)."

A spokesman said it estimated that producers contributed £100m a year towards recycling - that's between 25% and 30% of what they estimate is the total recycling bill.

He said that Valpak had recently calculated that the situation is not so bad as it is portrayed. The current collection rate for plastic drinks containers in the UK is actually 74% - not the 57%, he said - thanks to kerbside collection systems.

He added that government was considering changes to the PRN system which could involve an increased cost share by producers to fund specific activities.

Samantha Harding from the Campaign to Protect Rural England told BBC News that packagers were "dangling the carrot" of more cash from an improved PRN system in order to avoid a deposit-return system.

"At the moment, 90% of costs fall on the taxpayer and this isn't right," she said.

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