环境科学利用自然系统的物理，化学，生物和定量方面的基础知识。该知识适用于通常由人类活动引起的问题。在环境毒理学中，这些问题包括化学物质向空气，水和土壤中的释放，从而对生活在这些系统中的生物产生影响。影响通常对生物有害，并可能发生在生物组织的各个层面，包括：分子，细胞，个体，种群，社区和生态系统。
Students wishing to complete an Environmental Science Toxicology emphasis major in four years should complete the general chemistry series and the general biology series during their freshman and sophomore years. Prospective environmental science majors are strongly advised to take additional preparatory courses that provide a strong background in chemistry, biology and mathematics. The preparatory courses are listed with the major, preparatory classes may also be used to fulfill GURs. All preparatory courses required for admission should be completed on a lettered or numeric grading scale, not P/NP, and must be completed with a grade of C- or better.