Chlorpyrifos Use In California – The End Is In Sight

    Almond harvest. Photo:

    The use of the pesticide chlorpyrifos — sold under various product names, including Lorsban — will end in California at the end of next year as a result of an agreement struck on Wednesday between the state and manufacturers.

    Under the agreement with Corteva and other companies, all sales of chlorpyrifos products in California will end on Feb. 6, 2020. Growers will no longer be allowed to possess or use chlorpyrifos products in California after Dec. 31, 2020.

    The state said it is applying the settlement terms and deadlines to seven other companies not part of the agreement but are subject to the cancellation order.

    In May, the state announced it was moving to cancel all registrations of the pesticide, after the California Environmental Protection Agency announced the decision following a state scientific review panel’s findings that the pesticide causes “serious health effects in children and other sensitive populations at lower levels of exposure than previously understood.”

    Chlorpyrifos is the main ingredient in what was Dow AgroScience’s — now Corteva Agriscience’s — Lorsban insecticide, which also targets pests such as soybean aphids, spider mites and corn rootworm.

    Corteva told DTN the state of California made it difficult to continue offering the product in the state.

    “Through recent actions, the state of California has improvised and implemented several uniquely challenging regulatory requirements for chlorpyrifos,” the company said in a statement. “These new, novel requirements have made it virtually impossible for growers to use this important tool in their state. We have successfully negotiated a settlement for specific products and uses named in the accusation, which is in the best interest of the affected growers.”

    Usage Has Trended Lower Since Last Decade

    Chlorpyrifos use in California has been on the decline since 2005, according to the state’s department of pesticide registration. About 2 million pounds of the insecticide was used in 2005, but that fell to about 900,000 pounds in 2016.

    “For years, environmental justice advocates have fought to get the harmful pesticide chlorpyrifos out of our communities,” California Gov. Gavin Newsom said in a statement. “Thanks to their tenacity and the work of countless others, this will now occur faster than originally envisioned. This is a big win for children, workers and public health in California.”

    The agreement means use of chlorpyrifos will end sooner than anticipated in the state. Any manufacturers’ pursuit of administrative hearings and potential appeals could have taken up to two years.

    California has established a working group to identify pest-management alternatives to chlorpyrifos. The group is scheduled to hold its first meeting this month.

    The state said in a news release there is “mounting evidence that chlorpyrifos is associated with serious health effects in children and other sensitive populations at lower levels of exposure than previously understood, including impaired brain and neurological development.”

    Elsewhere In U.S., No Bans

    On a national level, however, the EPA continues to review chlorpyrifos but has not banned the pesticide. The agency has until 2022 to complete its review.

    The EPA made its decision in July as part of a court order issued on April 19, 2019, by the U.S. Court of Appeals for the Ninth Circuit in San Francisco.

    The EPA has consistently maintained available science supports the human safety of chlorpyrifos, while environmental groups continue to say it is unsafe for humans.

    On Nov. 10, 2016, then-President Barack Obama’s EPA announced plans to ban chlorpyrifos. That was reversed by the Trump administration.

    In August 2018, the Ninth Circuit ordered EPA to ban the use of chlorpyrifos. That was reversed by the full Ninth Circuit as a result of an en banc hearing.

    In April 2019, California formally listed chlorpyrifos as a “toxic air contaminant.” State law defines that as “an air pollutant which may cause or contribute to an increase in mortality or an increase in serious illness, or which may pose a present or potential hazard to human health.”

    In California, chlorpyrifos is used to control pests on alfalfa, almonds, citrus, cotton, grapes and walnuts.

    In 2015, the state-designated chlorpyrifos as a “restricted material” that requires a permit for its application.

    The national legal pursuit began in 2007 when the Pesticide Action Network North America and the Natural Resources Defense Council petitioned EPA to cancel chlorpyrifos registrations.

    A Columbia Center for Children’s Environmental Health study has been widely used as support for a ban, despite divergent scientific views among EPA scientific review panels, and former President Barack Obama’s administration’s USDA questioning the study and its data.

    A 2016 EPA scientific advisory panel indicated some members of that panel said they had difficulty assessing the study, because the raw data from the study was not made available.

    Here’s a list of the products involved.

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