A hidden substance lurks inside those spectacular bursts of red, white and blue decorating the skies on the Fourth of July — one you might not want seeping into your groundwater.

It's perchlorate, a chemical used to add oxygen fuel into many explosives and fireworks. Perchlorate is also a hazardous chemical that can cause problems in pregnant women and a medical drug used to reduce thyroid production.

In every big fireworks display, some of it floats from the explosion back to the ground, where it waits for a good rainstorm to help it seep into the groundwater.

A growing spinoff company out of Los Alamos National Laboratory, called DMD Systems, thinks one day it could prevent some of that contamination.

The company makes low-smoke, low-pollutant fireworks for indoor events, like those put on by World Wrestling Entertainment, Cirque de Soleil and Disney on Ice. But in the future, the company, located near Ojo Caliente, hopes its products could be used instead of the typical cheap, perchlorate-heavy fireworks used in today's shows.

"Most of the very large shells you see, and even the smaller ones you buy on the Fourth of July, come from China, and their environmental record isn't that great," said Darren Naud, chief executive officer of DMD. "Those large shells they make, they're full of perchlorate and other chemicals. And when you see things like all those stars falling to the ground in a display, you should realize they bring those chemicals back down to the ground with them."

Naud, Mike Hiskey and David Chavez were all scientists working on finding more environmentally friendly explosives at Los Alamos in the mid-1990s. At that time, their goal was to lower pollution content in flares and munitions used by the military, among other clients.

But somewhere in the process, Disney heard about the work and asked if the company could pay the lab to research a process for cleaner fireworks for its theme park shows.

"I gather the smoke was traveling from their parks in Florida and California and the neighbors were complaining," said Chavez, who is still a chemist at the lab.

The scientists found that if you used a nitrogen-based explosive, rather than carbon-based, you could reduce smoke from the fireworks. As an added bonus, the resulting fireworks burned so clean that less metals and chemicals were needed to make them colorful, Chavez said.

"So things like barium salt, which is used to make green, or strontium, which is used to make red, usually those are around 25 percent to 30 percent of the weight of a traditional fireworks formula," Chavez said. "But by using a different mix, we found we could drop those amounts by a factor of 10 — down to somewhere between 2 percent and 3 percent."

While the nitrogen-based explosives still need something like perchlorate to help them burn oxygen, they need a lot less of it, Naud said.

"We've also come up with some different oxidizing chemicals we can use so we don't need perchlorate at all in some of our products," Naud said.

The project with Disney ended several years ago, but the company uses some of the lab technology in its modern displays, Chavez said.

A few years ago, Naud and Hiskey decided to make similar products more widely available to the commercial market. So they formed DMD Systems, Naud said.

There is one drawback to the DMD products. They cost about eight times more than Chinese fireworks, Naud said. But the environmental benefits of the more expensive product is something people are starting to want to pay for, he said.

Naud said the company's main ingredient is nitrocellulose, which is made from cotton fibers and is used to make smokeless gunpowder. "It burns very well, and if it gets to the environment it may leave some plant fiber and a small amount of nitrogen, which is also used as fertilizer," he said.

That is a lot better than the mercury, chlorine and other chemicals used in Chinese fireworks, he said. "Chinese firework manufacturing can be very dangerous," Naud said. "Each year about 400 people in China die making them. And the fireworks are often made by people at home, then brought into the company so the quality varies dramatically."

The DMD product, on the other hand, is consistent, and it also looks great — especially on television, said Adrian Segeren, president of LeMaitre Special Effects Inc. in Alabama, which distributes the product.

"Smoke is always a problem with indoor pyrotechnics, and they make something fairly unique," Segeren said. "Their products are becoming more popular."

And with the U.S. Environmental Protection Agency considering a perchlorate drinking water standard — it doesn't have one yet — the environmentally friendly DMD fireworks could find itself with even more customers, Segeren said.

"Of course, it's the quality of the product that most people are looking for, and they make a very high-quality product," Segeren said.

Contact Sue Vorenberg at 986-3072 or svorenberg@sfnewmexican.com.