Ligand-activated Ca(2+)-permeable, nonselective cation channel involved in pain detection and possibly also in cold perception, oxygen concentration perception, cough, itch, and inner ear function (PubMed:17259981, PubMed:21195050, PubMed:21873995, PubMed:23199233, PubMed:25389312, PubMed:33152265). Has a relatively high Ca(2+) selectivity, with a preference for divalent over monovalent cations (Ca(2+) > Ba(2+) > Mg(2+) > NH4(+) > Li(+) > K(+)), the influx of cation into the cytoplasm leads to membrane depolarization (PubMed:19202543, PubMed:21195050). Has a central role in the pain response to endogenous inflammatory mediators, such as bradykinin and to a diverse array of irritants. Activated by a large variety of structurally unrelated electrophilic and non-electrophilic chemical compounds, such as allylthiocyanate (AITC) from mustard oil or wasabi, cinnamaldehyde, diallyl disulfide (DADS) from garlic, and acrolein, an environmental irritant (PubMed:20547126, PubMed:25389312, PubMed:27241698, PubMed:30878828). Electrophilic ligands activate TRPA1 by interacting with critical N-terminal Cys residues in a covalent manner (PubMed:17164327, PubMed:27241698, PubMed:31866091, PubMed:32641835). Non-electrophile agonists bind at distinct sites in the transmembrane domain to promote channel activation (PubMed:33152265). Also acts as an ionotropic cannabinoid receptor by being activated by delta(9)-tetrahydrocannabinol (THC), the psychoactive component of marijuana (PubMed:25389312). May be a component for the mechanosensitive transduction channel of hair cells in inner ear, thereby participating in the perception of sounds (By similarity). {ECO:0000250|UniProtKB:Q8BLA8, ECO:0000269|PubMed:17164327, ECO:0000269|PubMed:17259981, ECO:0000269|PubMed:19202543, ECO:0000269|PubMed:20547126, ECO:0000269|PubMed:21195050, ECO:0000269|PubMed:21873995, ECO:0000269|PubMed:23199233, ECO:0000269|PubMed:25389312, ECO:0000269|PubMed:27241698, ECO:0000269|PubMed:30878828, ECO:0000269|PubMed:31866091, ECO:0000269|PubMed:32641835, ECO:0000269|PubMed:33152265}. This is the function of TRPA1 (transient receptor potential cation channel subfamily A member 1, ENSG00000104321).