Only five studies corresponded to the validated and accepted method of 3T3-NRU phototoxicity (ECVAM, 1998; Spielmann et al., 1998; Gaspar, 2013; Ceridono et al., 2013).
It is surprising that so few studies were performed using this method, considering it was the first validated in vitro method to be accepted by the OECD (OECD, 2004).