There's no data to suggest small fireworks displays have a lasting impact on water ecosystems.

Bancroft This Week spoke to area lake associations and Hastings Highlands Mayor Vivian Bloom last month to discuss possible legislation for fireworks after concerns chemicals in them were a threat to local aquatic life.

According to Gary Wheeler, spokesperson for the Ministry of Environment and Climate Change, the only documented impact of fireworks on water quality is from large-scale displays.

“While there is some data suggesting that concentrations of metals may exceed water quality [thresholds] after large or frequent fireworks displays, [for example] those put on at theme parks, typical fireworks, [for example] those used by private individuals a few times per year, are unlikely to result in concentrations of metals that would be harmful to aquatic life or affect drinking water,” wrote Wheeler.

He added, “The risk to drinking water from infrequent, small-scale fireworks displays is low, as there is rapid dilution of any chemicals not destroyed through combustion or degraded in the environment.”

Wheeler said the scale of the impact depended on how many fireworks are released at one time and how often. 

“There are limited studies related to the impacts of fireworks on water quality (surface water or ground water).  The studies that are available were related to large scale, frequent, or annual displays as well as two that dealt with municipal displays,” he wrote. “None looked at ‘personal' use of fireworks, but we expect that fireworks available for public use would be smaller and contain less material that those used in ‘professional' displays, thus representing less impacts on the environment.”

Higher concentrations of chromium, copper, cobalt, molybdenum and vanadium were found in a study of Mission Bay, California, where fireworks were happening on a daily basis, he said.

 “Most studies did not detect significant increases in metals associated with fireworks in surface waters or groundwater after a display.”