According to new reports from federal authorities and researchers, there has been a dramatic increase in the number of illegal marijuana grows in California that are using dangerous pesticides. As a result, researchers said these illegal grows are harming animals and poisoning water sources.

Increase in Dangerous Chemicals

As reported by the Associated Press, new stats show that roughly nine out of 10 illegal cannabis grow sites are using dangerous chemicals in the cultivation process, including toxic pesticides, fungicides, and fertilizers.

These new stats represent a dramatic increase in the number of grows using harmful chemicals. For example, today’s rate of chemical use is reportedly six times higher than it was in 2012. And last year, 75 percent of illegal grows were using dangerous chemicals. Clearly, the number of sites using these types of chemicals has been steadily climbing.

According to researchers, when illegal grows use chemicals it can pose a significant risk to the local environment. In particular, pesticides and other similar toxins often end up poisoning local wildlife. Additionally, these chemicals leach into water sources, where they harm fish and spread toxins further downstream.

In some cases, researchers said that pesticides were being added directly to irrigation waters. Obviously, this can lead to significant damage as the chemicals flow to agricultural sites downstream and can contaminate the soil.

Officials are struggling to keep up with this dramatic increase in chemical use. Most notably, clean up projects are backlogged. In some cases, toxic cultivation sites have been waiting as long as eight years to be cleaned up.

This year, more resources are going toward cleaning up these toxic sites. So far, clean up crews have found 95 illegal grows and removed more than 10-tons of potentially harmful chemicals from these locations.

In total, clean up crews have worked on 160 sites. Authorities have seized more than 600,000 cannabis plants and over 25,000 pounds of harvested weed. Additionally, clean up crews have removed around 60 tons of garbage.

Carbofuran: A Deadly Chemical

Much concern has arisen in response to the increased use of carbofuran, an incredibly potent and deadly chemical that was originally intended to kill crop-eating insects. But it was quickly found to be so toxic that many countries around the world have banned it, including the U.S.

Carbofuran is so potent that researchers said just a quarter teaspoon of the insecticide can easily kill a 300-pound bear. Similarly, a single grain of the substance is enough to kill a bird.

The use of carbofuran has been especially alarming to researchers and authorities. In particular, as the number of grow sites using harmful chemicals has spiked, so has the number of sites using carbofuran.

According to reports earlier this year, carbofuran was discovered in over 70 percent of all illegal marijuana grows in California a year ago. That number represents a large increase compared prior years. Back in 2012, only 15 percent of illegal grows were found to be using the chemical.

The current trend of increased carbofuran is alarming for other reasons, too. This chemical is not meant to be consumed in any capacity, let alone heating up and then smoking. And, as of recently, grows using the chemical tend to use it in much more concentrated forms. This makes the already-dangerous chemical even more potent and more dangerous to water sources and local wildlife.