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Paraquat is a divalent cation and herbicide widely used across the globe. It is highly toxic to the kidneys, as well as the liver and lungs. Paraquat is excreted via glomerular filtration and tubular secretion [46]. Renal uptake of paraquat is presumed to occur via OCT2/Oct2 on the basolateral membrane [47]. hMATE1 and rMate1 demonstrate time‐dependent in vitro uptake of paraquat [47]. When expressed in proteoliposomes, hMATE1 is capable of transporting paraquat, but interestingly paraquat/proton exchange is stimulated by inside‐negative membrane potential and inhibited by inside‐positive membrane potential, which contrasts the electroneutral transport observed with prototypical substrates such as TEA [48]. Overexpression of hMATE1 not only enhances paraquat uptake but also heightens cytotoxicity by over 5‐fold compared with control cells [47]. In mice lacking Mate1, paraquat accumulates in plasma, lung, and kidneys to a greater extent than in wild‐type mice [33]. As a result, Mate1‐knockout mice exhibit enhanced susceptibility to paraquat‐induced nephrotoxicity [33]. While paraquat is a unique pesticide whose disposition and toxicity are dependent upon Mate activity, other classes of pesticides appear to have minimal interaction [49].