Latest figures show the amount of toxic chemicals released on Guam increased in 2010 compared with the previous year.
The United States Environmental Protection Agency's Toxics Release Inventory collates data on hundreds of toxic chemicals emitted by various industries.
According to the report, facilities on Guam released more than double the 2009 amount of toxic chemicals in 2010, at just under 221,000 kilograms.
The agency's Dean Higuchi says while the report is a valuable resource for communities and emergency responders, it doesn't evaluate risks to human health.
"Neither is it a way to determine whether or not a facility is technically in compliance or not. I would say all of these facilities would be in compliance but they're having to report their chemical releases."
Dean Higuchi says the top contributor, Tristar Terminal Guam, is revising its figure.
Tristar says an inputting error resulted in an inflated figure and it is aiming to have correct data to the EPA by the end of next week.