Researchers from the São Paulo State University in Brazil found that the chemicals in cigarette butts caused deformities in brine shrimp.
August 26, 2021
By Leta Dickinson
Human societies have long depended on ocean ecosystems for food, fresh water, clean air, transportation, medicines, and minerals. Unfortunately, human activities also affect the health of the ocean and its marine life, even if we live far away from the coasts. With widespread littering, mining, destructive fishing, ocean warming, and pollution, human impact on the very marine ecosystem that we depend on has been far more harmful than beneficial.
Cigarette butts are the most common litter globally, making up 30% of items collected on U.S. shorelines, waterways, and land. Unfortunately, cigarette butts are not only numerous but especially harmful because the thousands of chemicals they contain are toxic to marine life. Researchers from the São Paulo State University in Brazil observed that the chemicals contained in cigarette butts caused deformities in brine shrimp that were exposed to them.
The researchers placed five cigarette butts into seawater for three days. Then, they mixed this cigarette-infused seawater with clean seawater to create six solutions of varying concentrations, including a “control” solution with no cigarette-infused seawater, and a solution that was entirely cigarette-infused seawater. The researchers introduced larval brine shrimp into these solutions for two days before they were preserved and analyzed.
Perhaps unsurprisingly, the cigarette chemical slurry harmed the brine shrimp larvae. The larvae exposed to the highest concentration of cigarette-infused seawater (100%) all died. At lower concentrations, the larvae survived but experienced deformities in their antennae, body, and color that the larvae in the control solution did not. The higher the concentration of cigarette-infused seawater, the more abnormalities the researchers observed in the larvae.
This study only examined how one type of organism, brine shrimp, was affected by cigarette toxins. However, brine shrimp are marine grazers and are an essential food source in many marine ecosystems. They represent a keystone species that many other species in an ecosystem depend on. Abundant, healthy brine shrimp are necessary for a functioning and balanced ecosystem.
This study adds to mounting evidence linking tobacco products to adverse health outcomes. Previous studies have examined how chemicals seeping out of cigarette butts have harmed other marine life, such as fish, water fleas, bristle worms, and marine bacteria. Recent works have described how humans, especially young children, are harmed by exposure to tobacco chemical residue. If cigarette butts continue to be improperly disposed of, could the oceans too become a source of tobacco chemical exposure for people?
With all the human-caused issues plaguing our seas, reducing litter, especially cigarette butts, seems like one of the simpler ways to lessen our destructive impact. Unfortunately, even the best cleanup effort provides only a temporary fix for a tiny fraction of the more than 4 trillion butts annually thrown away. Smoking bans, cigarette litter abatement fees, phasing out cigarette filters, educational campaigns, and disposal of cigarette butts as hazardous waste have the potential to effectively reduce cigarette butt marine litter.
Click here to read the research study.