Researchers say mercury and other chemicals that were found in Lake Powell have moved downstream and are now being found in fish and aquatic plants in the Grand Canyon.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/geological-survey-study-finds-mercury-grand-canyon
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/washington-times-usa
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-pollution
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/mercury
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/united-states-america-us
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/ecology
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-quality