08 May 2023 --- Widely used insecticides and pesticides in California, US, contain high levels of chemicals that are contaminating millions of acres of farmland, according to the Center for Biological Diversity and Public Employees for Environmental Responsibility. Per- and polyfluoroalkyl substances (PFAS) are used most abundantly in California’s Central Valley on crops such as almonds, grapes, peaches and pistachios.