ROME - Already identified as a major threat to the health of the oceans, plastic particles have now been found on a glacier in Italy in a mountain environment famous for its pristine nature and clean air.

 Scientists from two Milan universities found 75 particles of microplastic in every kilo of debris deposited on the surface of the Forni Glacier in the Stelvio National Park in a study carried out last summer, the first such investigation of a terrestrial glacier environment.

 The scientists estimated that the Forni Glacier, one of the largest in the Italian Alps, could contain a total of between 131 million and 162 million plastic particles. Measuring less than 5 mm, the particles are believed to have been carried in on the wind and deposited from the clothes and equipment of climbers and excursionists.

 "Future studies will investigate biological aspects linked to their presence on the glaciers," Prof. Andrea Franzetti of Milan's Bicocca University was quoted as saying by La Stampa newspaper.

 "The microbiological decay of the plastic and the potential for its accumulation in the food chain will also be studied," he said. "It's now known that glaciers are not uncontaminated environments but collect a variety of pollutants that have been released into the atmosphere through human activity."

 Prof. Franzetti's findings were presented at a conference of the European Geosciences Union in Vienna in April. In order to avoid introducing contaminants themselves, the scientists wore only cotton clothing and wooden clogs while collecting samples on the glacier.

 An earlier study of glaciers in the Stelvio Park, using photography from unmanned aerial vehicles, documented an increase in debris cover on the glaciers from 16.7 percent to 30.1 percent of the total glacier area between 2003 and 2012, providing further evidence of the worsening pollution.

 Shrinking glaciers are themselves a measure of climate change and scientists now warn that the presence of microplastics in the mountains requires urgent study, to match investigation of plastic in water.

 Last year researchers found more than 1,000 small pieces of plastic per litre in water from the River Tame near Manchester, making the English river the most plastic-contaminated stretch of water in the world.

 A fire in a refuse treatment plant in the mountain town of Rogno, near Bergamo, recently sent acrid smoke drifting across an Alpine valley. The mayor banned outdoor activities and advised citizens to stay at home with their windows closed as a new source of air-borne pollution wafted over Italy's mountain environment.

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