A study by Taylor et al looked at human exposure to musks and evaluated their potential toxicity.

The primary source of exposure to synthetic musks is through exposure to scented personal care products or scented household goods. In a report evaluating the concentrations of synthetic musks in personal care products in China, Lu et al. found musk xylene in 19% of the products and they found musk ketone in 57% of the products tested. These products included hair care products, body washes, toilet soaps, skin lotions and make up.

Musk exposure has been associated with an increased risk of tumor formation in mice.

From the study:  “The body of literature supports the conclusion that not only are we being exposed to nitro musks, we are also bioaccumulating them and passing them on to our offspring through breast milk and perinatal exposures. While the animal studies do not address long-term low dose effects, they do indicate that a particular area of focus for health outcomes from nitro musk exposure should be tumor genesis and cancer.”