Matthew Winn, National Geographic's My Shot

Fireworks, picnics, mosquitoes, and a light summer breeze are the winning, all-American combination that few would trade on the Fourth of July. But with only a few small adjustments to the celebratory preparations, patriotic tradition can go hand-in-hand with environmentalism.

Though fireworks are typically only a once-a-year tradition, scientists are beginning to suspect that the radiant displays may not be entirely harmless to your health.

A 2007 study by the U.S. Environmental Protection Agency (EPA) found that fireworks displays next to an Oklahoma lake left perchlorate contamination for up to 80 days after the Fourth of July. (Perchlorate is an oxidizing chemical that can affect the functioning of the thyroid gland.)

Richard Wilkin, a geochemist with the EPA who authored the Oklahoma study, says there are still many knowledge gaps about the effects on water resources of perchlorate contamination from fireworks.

“But we should think about whether water bodies near where fireworks are set off are used for drinking water,” Wilkin said.

Other health experts are looking at whether heavy metals used to color fireworks may linger in the environment and caution against exposure to smoke, particularly for asthma sufferers, in cities that are blanketed in grey fumes after the ritual celebration.

Traditional fireworks manufacturers are looking for alternatives to perchlorate, according to Julie Heckman, executive director of the American Pyrotechnics Association, but she says there still isn’t much pressure on the industry to go green.

One pyrotechnics company, DMD Systems, has developed fireworks using nitrocellulose, a low-smoke ingredient. (Consider advocating that your municipality invest in DMD’s products for your local community display.) And Disney Imagineering, which puts on fireworks displays every day of the year at its theme parks, now uses a compressed air launcher to shoot off fireworks, reducing smoke and noise.

In Your Own Backyard

Heckman adds that consumer fireworks for the backyard are safe, though little research has been done on their ecological impact. One alternative is to hand out candles instead of sparklers.

Opportunities for greening the Fourth abound in picnic preparation. Reusable or biodegradable containers and utensils trump throw-away items for minimizing waste, and there are also a number of new green plastic items on the market. Eco-friendly purveyor Green Tooth has a wide selection of biodegradable and compostable tableware products made from corn and sugarcane, and Firebox.com sells a biodegradable picnic kit made from cassava fiber.

On the beverage side, dig out the old thermos and water bottles to transport drinks instead of individual bottles and cans. And consider bringing along a chemical-free insect repellent. Though hamburgers and hotdogs are stalwarts on the Fourth of July menu, tasty vegetarian options will leave a lower carbon footprint. If your family or guests stick to grilling meat, check out the Green Guide’s Beef Label Decoder for more sustainable purchases.

For more eco-friendly holiday tips, visit Green Guide's Holiday Guide.