Microplastics are everywhere — including in Nevada’s snowpack. After years of skiing on freshly fallen snow in remote locations across the Sierra Nevada, Aleksandra Karapetrov — an environmental toxicologist at the University of California, Riverside — wondered how pristine the snow really was. Over six months, Karapetrov and a team of University of California, Riverside scientists tested fresh snowfall at seven sites across the Sierra Nevada and found something they did not expect: a steady delivery of tiny plastic fibers, even in the most remote locations. … The study, published this month in the journal Environmental Science and Technology, found significant amounts of microplastics in fresh snowfall at both remote and populated sites across the Sierra Nevada, which supplies about 60% of freshwater in northern Nevada.