When released into the atmosphere, helium balloons are able to travel vast distances (more than 10,500 miles). Every balloon will eventually land, becoming litter on beaches, rivers, lakes, oceans, and other natural areas. As a direct result, seabirds and other wildlife can be injured or killed from ingesting the balloon debris and/or becoming entangled in the long ribbons or strings.
Between 2016 and 2018, volunteers with The Alliance for the Great Lakes picked up more than 18,000 pieces of balloon debris. The International Coastal Cleanup, an annual event organized by the Ocean Conservancy, recorded finding over 280,000 balloons in the United States and over 630,000 balloons worldwide between 2008 and 2016.
There are two types of balloons - mylar and latex. Mylar balloons, made from nylon (a plastic material) with a metallic coating, will never biodegrade. Mylar balloons are also responsible for power outages when they hit power lines and/or electric circuit breakers. For example, in 2018, mylar balloons caused over 1,100 power outages in Southern California. They were also responsible for 619 incidents and delays at railway stations across England, Scotland and Wales, and end up costing British taxpayers around £1m a year.
While some manufacturers claim that natural latex balloons made from liquid rubber are 'biodegradable', they are in fact mixed with plasticizers and other chemical additives that hinder the biodegradation process. (Read about a new scientific study that tested the claim that latex balloons are 'biodegradable' here.) Other latex balloons are synthetic, made from a petroleum derivative called neoprene (the same material used to make scuba diving wetsuits) and will remain in the environment indefinitely.