Toxic tort.... Is it too late?

My father worked in hazardous waste removal for many years. We believe he was exposed to arsenic on one job (which the employer denied the BWC claim for contact dermatitis). Most of his health conditions fit those relating to long term arsenic exposure, including blistering of his hands after cutting his finger nails (14 years after exposure).**all research I've done says the nails only last for a few months** No doctor has diagnosed him with anything relating to arsenic exposure and the power plant he was working out of has since closed. I know with toxic torts there is the statute 2 years from finding out you're injured as a result of the exposure.... With no point blank diagnosis of "arsenic exposure" is it a viable claim or too late?