It's turning into a bad day for the Environmental Protection Agency (EPA), as a government watchdog has claimed the agency didn't inform study participants of the fatal risks involved in EPA pollutants research. About 80 people were recruited for pollutant studies in 2010 and 2011, in which they were exposed to soot and diesel exhaust. The study consent forms did not consistently state the risk of cancer, since the agency deemed it as a small risk. Yet, the EPA warns of how dangerous and deadly small particles and diesel exhaust can be. Ironic, isn't it?

Louisiana Republican Senator David Vitter certainly thinks so, releasing the following statement in reaction to the report: "When justifying a job-killing regulation, EPA argues exposure to particulate matter is deadly — but when they are conducting experiments, they say human exposure studies are not harmful."

Participants were brought into test labs and exposed to the pollutants for a short time. The consent forms stated that their exposure is comparable to being in a large city on a "smoggy day." But the forms did differ between studies, sometimes reporting the full risks.

There are potentially 19 substances that can cause cancer in diesel fumes. Since participants were only exposed to the pollutants for two hours and cancer develops over several years of exposure, the agency, which has performed pollutant studies on human test subjects for 40 years, says cancer risk wasn't a concern worth mentioning.

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While no one died as a result of these tests, several participants reported "adverse" effects, ranging from migraines to decreased lung function, and those participants were treated. Plus, according to the EPA inspector general report, test subjects would like to know if there is a risk of death, even if it's a minor risk. (We think we'd want to know, too.)

Of course, the EPA has released a written statement, saying they will improve the language used on consent forms in the future, but also noting the agency does follow "all laws and regulations" when it comes to testing on humans. The EPA added that its standards and guidelines are even higher than what is required at universities, as well as other industry and government research facilities.

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The agency is allowed to perform human testing under federal law, having spent millions on pollutant research. The best way to get test subjects? Money. In these particular studies, participants were paid between $950 and $3,700. For that kind of money, human test subjects will probably continue to sign up, but at what cost to their health? Here's hoping the EPA follows through and fully informs it's test participants from now on.