A bachelor's degree in environmental health sciences or a related field meets the minimum requirements for trainee positions, but a master's degree is required for other positions and desirable for career advancement.
Health science is a broad field that involves the study and research of multiple aspects of health and healthcare.
Health sciences departments typically provide training for a wide range of careers, such as health services administration, nutrition, public health and occupational therapy.
Three popular career tracks in master level are health sciences (environmental health, biostatistics and health administration).

The scope is good and broad.

Good luck.