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Boston News

Scientists to Swimmers: Stop Peeing in Walden Pond

A new study found elevated levels of phosphorus from human urine in Thoreau's legendary escape.

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How the times have changed: Walden Pond, made famous as the site where Henry David Thoreau escaped to the pristine wilderness, is polluted with human urine from swimmers, a new study reports. Scientists found elevated levels of phosphorus in the water, which fuels algae growth and reduces water clarity.