A new analysis by EWG Action Fund concludes that up to 15,000 Americans die every year from asbestos-related diseases, significantly more than previous estimates.

The findings indicate that 50 years after medical research definitively established that asbestos kills, the government still can’t say for certain how many Americans die from asbestos exposure.

EWG Action Fund’s researchers analyzed death records from the Centers for Disease Control for 1999 to 2013, identifying all deaths attributed solely or in part to mesothelioma or asbestosis, the two diseases tied exclusively to asbestos exposure. In addition, EWG Action Fund estimated the number of Americans who die of asbestos-triggered lung cancer, using a formula developed by researchers of the International Agency for Research on Cancer. Studies show elevated lung cancer rates among asbestos-exposed workers, who were often heavy smokers. The International Agency’s method provides a way to quantify the role of asbestos in lung cancer deaths.

In all, EWG Action Fund calculated that asbestos exposure was responsible for 12,000 to 15,000 deaths annually over the fourteen-year period from 1999 to 2013 – 2,000 to 5,000 more than previous estimates. Because there is a long lag time between asbestos exposure and the onset of disease, there was no observed decline in asbestos-related deaths over the period despite the significant drop in asbestos use in recent decades.

Asbestosis is recorded as the primary cause of death in only 40 to 50 percent of asbestosis victims; in others it is recorded as a contributing cause. As a result, EWG Action Fund’s estimates of asbestosis deaths are higher than those of the U.S. Centers for Disease Control and Prevention, which only considers the primary cause of death.

However, EWG Action Fund’s estimates are still probably too low, because the deaths of patients with symptoms of pneumonia or other respiratory diseases may be attributed to those diseases or to lung fibrosis of unknown origin. Moreover, the actual death toll may be even higher, said a former U.S. assistant surgeon general.

“As shocking as these figures are, they may be too low,” said Dr. Richard Lemen, an epidemiologist who served as assistant surgeon general during the Clinton administration. “The report did not estimate deaths from other asbestos-related diseases,” commented Lemen, who was not part of the EWG Action Fund report. “Furthermore, some studies suggest even higher lung cancer rates in asbestos-exposed workers.”

Asbestos exposure is also known to cause cancer of the larynx and ovaries and has been linked to colorectal and stomach cancer. The number of asbestos-related deaths in the U.S. from these diseases is impossible to estimate based on existing evidence, but it is likely fewer than from mesothelioma, asbestosis or lung cancer.

“Clearly, asbestos kills more Americans each year than we thought,” said Sonya Lunder, a senior research analyst with EWG and EWG Action Fund. “The fact that it is still legal and used in the U.S. is an outrage.”

As EWG Action Fund reported earlier this year, although asbestos is no longer mined in the U.S., it continues to be imported. Since 2006, at least 8 million pounds of raw asbestos and asbestos-containing materials have arrived in U.S. ports.

“The only way to see the numbers of asbestos-related fatalities significantly decline among Americans is for our elected leaders to adopt an outright ban on the deadly substance,” added Lunder.

Congress is considering a bill that would make it harder for asbestos victims and their families to receive compensation for their illnesses and deaths. The Furthering Asbestos Claim Transparency Act, introduced in both the House and Senate and strongly supported by the asbestos industry, would effectively run out the clock on dying asbestos victims before they are able to collect compensation through special asbestos trusts that were set up to indemnify them for their suffering.

The bill would require the trusts to issue quarterly reports that would drain their resources, ensuring that victims would collect less than fair compensation. The reports would also publicly disclose personal information, including medical histories, of those seeking compensation. Asbestos companies could ask for any additional information related to victims’ claims at any time, resulting in endless unnecessary paperwork.

“As this report shows, thousands of Americans still die every year from asbestos-related disease,” said Sarah Grantham, a policy analyst at EWG Action Fund. “This legislation would deliver the final blow to many asbestos victims, again from the hands of the very industry that poisoned them to begin with.”

EWG Action Fund’s analysis of the federal data showed that from 1999 to 2013, mesothelioma, a type of cancer, was listed as the cause of 39,870 deaths, or about 2,848 a year. Asbestosis, which scars the lungs, was listed as the cause of 20,317 deaths, or about 1,451 a year. A combination of both conditions was listed as the cause of 1,285 deaths, or about 92 per year.

To estimate the number of asbestos-linked lung cancer deaths, the new analysis relied on a review by the International Agency’s scientists of 55 studies that reported the rate of both lung cancer and mesothelioma in asbestos-exposed groups. They estimated that in the U.S. there are 3.2-4.0 lung cancer deaths for every mesothelioma death among people exposed to mixtures of different types of asbestos. Applying that ratio suggests that from 1999 to 2013 an estimated 127,579 to 159,480 in all Americans died of lung cancer caused by asbestos exposure – about 9,113 to 11,391 deaths a year.

Related: Extreme Cases of Asbestos