Negatively regulates cellular toxicity by mediating the export of environmental toxicants such as methylmercury out of the cell (PubMed:24266639). Plays a role in inhibiting methylmercury-induced dopamine (DA) motor neuron degeneration (PubMed:24266639). Not involved in Mn(2+)- or Al(3+)-associated toxicity (PubMed:24266639). Expressed in head neurons, including the dopamine (DA) motor neuron, and other cells in the body. Up-regulated in response to environmental toxicants such as methylmercury. RNAi-mediated knockdown results in increased death in response to the environmental toxicant methylmercury (PubMed:24266639). Furthermore, in response to methylmercury, RNAi-mediated knockdown results in the accumulation of the methylmercury in cells, the subsequent increase of gst-1, hsp-4, hsp-6, and hsp-16.1 gene expression, and in dopamine (DA) motor neuron degeneration (PubMed:24266639). Belongs to the ABC transporter superfamily. ABCC family. Conjugate transporter (TC 3.A.1.208) subfamily.