Loss of bone mineral density is the leading cause of fracture among older individuals and a major cause of disability and death. Skeletal fragility, or osteoporosis, is usually considered a disease of aging, but bone health should be considered across the lifespan. Adequate accumulation of bone mass during the earlier decades and slowing of bone loss that occurs with aging can reduce risk of fracture-associated disability and death in later decades. There is evidence that exposure to environmental contaminants contributes to bone thinning, reduced bone accumulation, changes in bone structure, and alterations in bone homeostasis. This chapter discusses current research connecting bone alterations and exposures to environmental contaminants and explores mechanisms of action, social vulnerabilities such as race or other minority status, and implications for public health and public policy including medical and social costs.