The Ocean’s Food Chain Threatened By Skin Cream

Clotrimazole is a common ingredient in over-the-counter skin creams used to fight fungal infections. Researchers at the University of Gothenburg, Sweden, now show that it is contaminating the oceans and may be disrupting the food chain.

“The pharmaceuticals and chemicals in everyday use form a mixture in the ocean that has a direct impact on the growth and reproduction of organisms,” says researcher Tobias Porsbring.

“The levels of clotrimazole that are measured in the environment affect the synthesis of sterols in the algae and these are important in several functions in the algal cells. The growth and reproduction of the algae are disturbed. Single-cell microalgae are the fundamental basis of the ocean food chain, and the use of clotrimazole thus may affect the complete ocean ecosystem,” warns Porsbring.

Clotrimazole, however, does not act alone in the ocean ecosystem. Many other substances are often found in the oceans, including propranolol (a drug to lower blood pressure), triclosan (an antibacterial agent commonly found in soap and deodorants), fluoxetine (an antidepressant pharmaceutical) and zinc pyrithione (found in anti-dandruff shampoos). Porsbring’s findings suggest that a mixture of such compounds forms a “cocktail effect” that has a direct, harmful impact on the growth of the ocean’s microalgal community.