Pesticides are a substance or mixture of substances intended for preventing, destroying, repelling, or mitigating pest. Pesticides can contaminate soil, sediments, water, and other vegetation.

1,4-Dioxane (14-DX-1)
Section 1.2.9 (Pesticides)
There is some evidence that past pesticide formulations contained 1,4-dioxane as an inert ingredient, including in the range of 20%–50% of the formulation.

Incorporating Bioavailability Considerations into the Evaluation of Contaminated Sediment Sites (CS-1)
Appendix B- Categories of Contaminants (Pesticides Section)
Discusses general information about pesticide contamination and how it reacts in sediments.