Given the complexity of Syria's case, the labs could become more important. Chemical weapons inspectors still are planning where and how to destroy Syria's stockpile. The weapons likely will be moved out of the country for destruction because the continuing Syrian civil war would make it difficult and dangerous to move inspectors and equipment into the country.

At least two labs would receive any samples from the Syrian stockpile, and it's likely inspectors would favor facilities in Europe because they are closest, Trapp said. But extra consideration could be given to labs with expertise in scrutinizing biological samples, such as the blood, urine or tissue of victims, if such samples require testing, he said.

Officials at the Aberdeen lab said they are capable of testing biological samples such as urine.

Wherever the testing occurs, the efforts to demilitarize Syria's chemical stocks are uncharted territory for the OPCW and world leaders, said Milton Leitenberg, a senior research scholar at the University of Maryland's Center for International and Security Studies at Maryland.

It is believed that Syria began developing chemical weapons in the 1980s as a response to Israel's nuclear weaponry program, which dates to the 1960s, though Syria never publicly acknowledged its stockpiles, Leitenberg said. Now, the country has agreed to turn them over under intense political pressure and threat of U.S. military action, despite Assad's denying responsibility for the sarin gas attack.

"I don't know that there's any other precedent for a country denying possession and then admitting it in a very small way," Leitenberg said. "The OPCW has not had a role of this sort ever before."

In Edgewood, the Army chemists are aware of their work's importance and take pride in being part of the OPCW's network. The lab's staff of 18 spends 15 days straight each year, typically in the spring, deciphering the contents of six samples as a test to maintain the partnership.

"It's kind of like a big puzzle," said Joy Ginter, a research chemist in the lab.

The samples may be a drop of liquid, a glob of glue or a solid residue. The chemists aren't told how many compounds each might contain, and they often find that the tests, prepared and graded by separate peer labs, contain curveballs.

In one test, the Edgewood lab was one of only two to find and correctly report a compound that is not named in chemical abstracts, but that the chemists were able to detect, break down and identify.

"They know the things that make samples hard, so they put those in the test," said Alexis Jestel, a chemist who coordinates the lab's test efforts. "It's harder than any real-life scenario. They can have confidence in that data because the labs have dealt with much worse."

They acknowledge that's because it's vital that they get it right when it comes to the real-life samples.

"What you do has tremendous consequences," said George Hondrogiannis, a senior scientist at the lab.

Reuters contributed to this article.