- © The Mineralogical Society
The increasing presence of pesticides in natural ecosystems has stimulated research to look for improved adsorbent materials which can be used to remediate and prevent soil and water contamination by these compounds. Among the different materials that have been assayed as adsorbents of pesticides are natural clay minerals, particularly 2:1 phyllosilicates and their structurally complementary synthetic analogues layered double hydroxides (LDHs). The great interest in natural clays and LDHs as adsorbent materials is mainly related to the large specific surface areas associated with their layered structure, the ease with which they are obtained or synthesized, and the possibility of modifying their surfaces to increase their affinity for specific adsorbates. This review summarizes the adsorptive properties of natural clays and LDHs for pesticides and related organic compounds. Particular emphasis is given to the surface modification of clay minerals and LDHs with organic ions as a strategy to improve the efficiency of these materials as pesticide adsorbents. Potential applications of unmodified and modified clays and LDHs as adsorbents to prevent and remediate soil and water contamination by pesticides are also discussed.