California’s wildfire responsible for contaminated water sources in the state

In August, California witnessed a large wildfire that tore through the San Lorenzo Valley north of Santa Cruz. It destroyed almost 1,500 structures and exposed many others, including humans, to extreme levels of heat. Lab tests that were carried out during the fire revealed benzene levels as high as 9.1 parts per billion in residential water samples—nine times higher than the state’s maximum safety level.

Experiments carried out by scientists explain recent high benzene level in water

In addition to benzene, California water managers found unsafe levels of other volatile organic compounds (VOCS).

Andrew Whelton, an environmental engineer at Purdue University in West Lafayette, and his colleagues subjected commonly available pipes to temperatures from 200° Celsius to 400 °C—the temperature range in the environment during wildfires.


The researchers, after cooling the pipes in water, found varying amounts of benzene and VOCs-more than 100 chemicals in some tests—in the water. The chemicals were gotten from the materials used to make the pipes.


“Some contamination for the past fires likely originated from thermally damaged plastics,” says Whelton. It’s impossible to do experiments in the midst of a raging fire to pinpoint the exact source of the contamination, but inspecting damaged pipes after the fact can suggest what temperatures they may have experienced,” he added.

High benzene level in water may lead to health problems

This isn’t the first time benzene has been noted after a wildfire: unsafe levels of benzene and other volatile organic compounds were found in Santa Rosa after the Tubbs Fire in 2017, and in Paradise after the CampFire in 2018.


Benzene exposure is dangerous, as it can cause immediate health problems, including skin and throat irritation, dizziness, and longer-term effects such as leukemia.


Most scientists suggest testing drinking water if fire comes anywhere near your property and, if possible, replacing any plastic in a home’s water system with heat-resistant metal.