Image copyright Phil Ellery Image caption Phil Ellery photographed these washed-up cartridges with a toy gorilla he found at Mawgan Porth, Cornwall

Thousands of Hewlett Packard printer ink cartridges are believed to be washing up on beaches around Britain and Europe after being lost at sea more than a year ago.

The cartridges have been found along the UK's south and west coasts, as well as the Irish Republic, France, Portugal, the Azores, and the Hebrides.

Conservationists say any plastic in the sea presents a hazard for wildlife.

HP says it is finalising a financial donation to help the clean-up.

It comes after thousands of bright pink plastic detergent bottles washed up on beaches in Cornwall earlier this week, likely to be the result of an unrelated loss of cargo at sea.

Image copyright Tracey Williams Image caption Some of the washed-up HP cartridges have barnacles, indicating a lengthy time in the water

Image copyright Marianne Odendahl Image caption Marianne Odendahl found these cartridges on Santa Maria island in the Azores

'Patterns emerging'

Beachcomber Tracey Williams, who lives in Newquay, first found the printer cartridges last summer.

"I started finding them on Perranporth Beach, and thought it was a bit odd, but I'm in touch with several beachcombing groups elsewhere and they started reporting them too," she said.

She then began tracking reports of their discovery using her Facebook page.

"Patterns started emerging. We've only been recording them for the last month or so, but now that word has spread we're getting daily reports - people finding eight or 10 at a time.

"What has been mapped so far is just what we know about. There must be many more out there. We had a report this week of 100 being found on another island in the Azores.

"I would imagine there are thousands washing up or something like that. I and other beachcombers think what has been reported so far is just the tip of the iceberg."

Ms Williams has previously been contacted by a man in the remote Flores Island, part of the Azores island chain in the Atlantic, who says he began finding HP cartridges on its shores at the start of 2014.

The highest concentration of cartridge finds that Ms Williams has recorded so far is in Cornwall, Devon and Dorset. Many have also washed up at County Kerry in the Irish Republic.

Ms Williams has previously tracked washed-up Lego pieces which were lost in a container spill in 1997.

"The whole business of container spills is very difficult. No company wants it to happen. But who's going to pick up the pieces? It's usually left to beachcombers and conservation groups," she said.

"If HP donate a decent sum to help with the clean-up then I'd welcome that."

Image copyright Rebecca Thomas Image caption Rebecca Thomas's children Lola and Lily found cartridges and Lego at Freshwater West in Pembrokeshire

Image copyright Jean-Yves le Tollec Image caption This cartridge was found by Jean-Yves le Tollec in Mousterlin, Brittany

HP said in a statement that the cartridge spill was the result of an Atlantic storm more than a year ago, where a number of cartridges were lost at sea. It also says it is "unable to provide details on the number of cartridges or exact location" of their loss.

It added: "Based on global standards, we can confirm there is no risk to sea life from the ink as it is water based.

"We are in the process of setting up a fund in partnership with the Marine Conservation Society to support the collection of the cartridges and very much appreciate the support of the local beach cleaning organisations and individuals who have been doing so."

The company was finalising details of a donation, a spokeswoman added.

HP has set up a free phone line and email recycling service, for anyone who finds a cartridge on a beach, adding that it is "committed to collecting and recycling the products as quickly and efficiently as possible".

It has not indicated how much it will donate towards any clean-up operation.

HP cartridge recycling hotline

Image copyright Tracy Vibert

For the United Kingdom

Requests should be made to 0800 0969766 or ukoperations@erp-recycling.org

For the Irish Republic

Requests should be made to 1800 848 859 or info@erpcollect.ie

Oceanographer Curt Ebbesmeyer believes the pattern of the washed-up cartridges indicates a spill in the Gulf Stream with a split in the flotsam, one part heading south to the Azores, the other splitting off to the north towards the UK, and possibly on to Norway and into the Arctic.

He also estimates that the number of cartridges lost is about 370,000, based on the dimensions of a 40-foot container.

"Beachcombers usually report some 3% of flotsam released at mid-ocean, so you might expect reports of some 10,000 cartridges," he added.

Image copyright Jason Paul Tolmie Image caption Jason Paul Tolmie has found HP cartridges among several washed-up items in the Hebrides

Image copyright Ana Pego Image caption Ana Pego found this cartridge on a beach at Cabo Raso, Cascais, in Portugal

Image copyright Rosemary Hill Image caption Irish-based beachcomber Rosemary Hill has found plenty of the lost cargo in County Kerry

Laura Foster, of the Marine Conservation Society, says plastic in the sea breaks down into smaller pieces and is ingested by marine life, which mistakes it for food.

She says studies have shown that up to 52% of sea turtles may have ingested various debris, and 95% of northern fulmar birds in the North Sea had plastic in their stomachs.

"We advocate that containers on ships are properly fastened and secured, and hope there's a fast response from companies when containers are lost at sea.

"It's not their direct fault, but it is important that companies look at cleaning it up."