Possession of a Doctor of Philosophy (PhD) degree in toxicology; or, a PhD in a physical, biological, or environmental science with 10 semester (15 term) credits in a one or more subject areas including toxicology, human or environmental risk assessment, pharmacology, pathology, environmental stress, mechanisms or modes of chemical action on living organisms; and an additional 10 semester credits (15 term) in any combination of the following: molecular biology, biochemistry, chemistry, anatomy, epidemiology, industrial hygiene, zoology, ecology, biology, limnology, environmental science, soil science, physiology, histology, statistics, and chemical fate and transport may be substituted for two years of toxicologist experience equivalent to the 10 level. Possession of a master's degree in a physical, biological, or environmental science with 10 semester (15 term) credits in one or more of the following subject areas: toxicology, human or environmental risk assessment, pharmacology, pathology, environmental stress, mechanisms or modes of chemical action on living organisms; and an additional 10 semester credits (15 term) in any combination of the following: molecular biology, biochemistry, chemistry, anatomy, epidemiology, industrial hygiene, zoology, ecology, biology, limnology, environmental science, soil science, physiology, histology, statistics, and chemical fate and transport may be substituted for the education requirement.