Pesticide linked to bee die-offs found in California’s urban waterways

Sacramento, Calif.– Across California, neonicotinoids or “neonics,” a widely used class of insecticides linked to bee die-offs, are contaminating urban waterways. Water sampling conducted by the California Department of Pesticide Regulation (DPR) found that 92% of urban water samples in Los Angeles, Orange and San Diego County and 58% in urban areas of Alameda, Contra Costa, Placer, Sacramento and Santa Clara County contained the neonicotinoid imidacloprid at levels above EPA’s chronic benchmark for harm to aquatic ecosystems. 

“The percentage of urban waterways contaminated with this bee-killing pesticide is startling, and it bodes poorly for efforts in California to save the bees,” said Ben Grundy, Conservation Associate with Environment California. “Clearly we have to do much better than this, and that starts with a bill to restrict pesticides that’s sitting with the governor.” 

According to the California Department of Pesticide Regulation (DPR), there are 253 pesticide products registered for use in California that contain imidacloprid as an active ingredient. These products include flea prevention products for pets, in-home pest control products, and plant fertilizers.

“Every Californian knows the importance of having access to safe, clean water. Neonics like imidacloprid are causing harm not only to our pollinators and birds on land but also to our aquatic wildlife,” said Steve Blackledge, Conservation Program Director for Environment America. “Neonics are also being found in our bodies and despite being framed as ‘mammal-safe,’ recent research suggests that neonic exposures may increase the risk of developmental and neurological harms.”

Specifically, in Los Angeles County, samples collected by DPR at the Los Angeles River, Ballona Creek, Compton Creek and Bouquet Creek, Dominguez Channel, contained imidacloprid. 

In Alameda County, samples from the South San Ramon Creek, Martin Canyon/Koopman Canyon Creek, Arroyo De Laguna, San Lorenzo Creek, Alameda Creek, Ettie St. Pump Station and Emeryville Crescent State Marine Reserve (North) contained imidacloprid. 

Samples collected In Sacramento County revealed that Arcade Creek, Alder Creek and the Sacramento River all contained Imidacloprid.

Find out the Imidacloprid level in your local waterway using Environment California’s map.

Neonicotinoids like imidacloprid are systemic pesticides, which means that plants uptake the imidacloprid through their roots from the soil or through their leaves. Imidacloprid then permeates the plants, making their pollen, fruit, and nectar toxic. Additionally, imidacloprid can remain in soil for long periods of time and be transported by rain or irrigation systems, which leads to imidacloprid contamination in California’s waterways. 

California has an opportunity to reduce the risk of Imidacloprid exposure in urban waterways.

Colloquially known as the “Save the Bees Bill,” Assembly Bill 2146, introduced by Assemblymember Rebecca Bauer-Kahan (AD-16) and currently awaiting a signature from Gov. Gavin Newsom, seeks to end non-agricultural uses of neonicotinoid pesticides on gardens, lawns and golf courses. 

Scientists, farmers, beekeepers and more have sounded the alarm: bee colonies are in collapse. More than half of native bee species in North America are likely in decline and beekeepers last year reported losing 45.5% of their honey bee colonies, the second highest annual loss rate on record.

“Our pollinators play a critical role in maintaining the health and beauty of our environment here in California,” said Grundy. “If we don’t take action now, future generations of Californians won’t get to experience the diversity of  fruits, nuts and vegetables that all of us now enjoy.”

With widespread pesticide use taking place on California’s agricultural lands, urban and suburban areas are some of the best havens left for bees. Agricultural use of neonics is now being regulated by the Department of Pesticide Reform, but non-agricultural use is largely unregulated. 

“We want to make California the next state, and the largest, to take this important step. The bill already passed through the Legislature, so we’re now urging Gov. Newsom to sign the bill into law,” said Laura Deehan, Environment California state director. “We must prioritize the preservation of our pollinators over the short term convenience of massive pesticide use.”

View the imidacloprid map press conference on Environment California’s Facebook Page.