Since glow sticks are pretty small, you might think they have a small environmental impact.
However, they can quickly build up.
Glow sticks are not good for the environment since they’re made of plastic, which is non-renewable, and there are concerns about some of the chemicals in them.
Here’s everything you need to know about glow sticks and the environment.
1. What Are Glow Sticks Made Of?
Although the exact chemical composition in glow sticks varies – e.g. depending on the color it will produce – all glow sticks generally share some basic similarities.
The outer container of a glow stick is a flexible plastic tube, which contains a mixture of a liquid capable of fluorescing (the “fluorescer”) and an oxalic acid ester.
Typically, polycyclic aromatic hydrocarbons (PAH) are used as fluorescers.
Dibutyl phthalate (DBP), dimethyl phthalate, or ethyl acetate are often used as solvents for the ester as well as a catalyst, usually sodium salicylate.
Inside the glow stick is a glass tube that is filled with a hydrogen peroxide solution, which means it is initially separated from the fluorescent liquid in the plastic tube.
When the glow stick is bent, the glass breaks, releasing the hydrogen peroxide solution, allowing it to mix with the fluorescer, causing a chemical reaction to occur and the mixture to glow.
Different colors are achieved by using different dyes for the outer plastic tube or, alternatively, by mixing different fluorescers (e.g. red, yellow and green to achieve orange).
2. Are Glow Sticks Toxic if Broken?
Generally, when you snap glow sticks, the chemicals do not escape from the plastic, so they do not spill or come in contact with you or the environment.
However, some of the ingredients in glow sticks or the byproducts of the chemical reaction may be harmful and even toxic.
Research found that the contents in glow sticks were toxic to human cell cultures and well as genotoxic, meaning they can damage the cell DNA and so potentially cause mutations and cancer.
Moreover, the researchers found that when solution from used glow sticks was applied to rats for four days, they experienced inflammation, as well as erythema, edema, epidermis proliferation and vesicles.
The study concluded that both fresh and spent glow stick contents are hazardous and the health risks from exposure have not yet been fully evaluated, indicating an urgent need for adequate waste management of these substances.
Other studies show that Dibutyl phthalate (DBP), also contained in some glow sticks, is toxic to humans and animals and considered carcinogenic as well as an endocrine disruptor.
DBP is one of many phthalic acid esters, which are considered top priority toxicants by the European Union and the EPA in the US.
The polycyclic aromatic hydrocarbons (PAH) commonly used as fluorescers are also toxic and carcinogenic.
Studies show that PAHs have a long half-life and a tendency to accumulate in the environment, which makes them a problematic environmental pollutant.
Even worse, they cause a range of toxic derivatives during their slow degradation.
The commonly used catalyst sodium salicylate is known to cause eye, skin and respiratory irritation and is harmful if swallowed.
Phenol, which is produced as a by-product of the chemical reaction in glow sticks, is corrosive to the skin, eyes and lungs.
It is absorbed quickly through the skin or its vapor can easily be inhaled.
So while exposure to the content of a glow stick is not deadly to humans, they do contain some hazardous chemicals, which is why they should be treated with care, disposed of responsibly and exposure to their content avoided.
3. Are Glow Sticks Bad for the Environment?
Yes, glow sticks are bad for the environment for multiple reasons.
Plastic is sourced via mining which causes pollution and environmental destruction.
Moreover, glow sticks are single-use items, so while they’re small, they can quickly add up.
This also means there is always a demand for new glow sticks, which require more energy and resources.
If not disposed of properly, these can quickly contribute to plastic pollution.
If that happens, glow sticks will eventually break down into microplastics and release their hazardous chemicals into the ocean.
Microplastics and chemicals can also easily enter the human food chain when people eat fish; microplastics may even be harmful to human health too and cause inflammation or have adverse effects on the immune system.
Secondly, even if used glow sticks were disposed of properly, they are non-recyclable waste and as a result, often pollute the environment.
This is because spent glow sticks contain a mix of hazardous chemicals and shattered glass, which makes both the glass and the plastic unrecoverable.
Therefore, used glow sticks generally end up either in landfill or the environment.
But in both cases, there’s the risk that the hazardous chemicals will sooner or later leak out into the surrounding soil or water.
4. Are Glow Sticks Reusable?
No, conventional glow sticks are not reusable.
You can’t turn them on and off, so they remain fluorescent until the chemical reaction is complete.
While you can slow down the reaction and get longer use from glow sticks by placing them in the fridge or freezer before using them, this still doesn’t mean they’re actually reusable.
After the chemical reaction is complete, nothing will happen if you snap them again and there is no way to make them glow again.
There are LED sticks powered by batteries that can be reused, but these are not the same as typical glow sticks.
5. Are Glow Sticks Recyclable?
Glow sticks are not recyclable.
While glass and plastic may be recyclable individually, you can’t separate all the chemical components of a glow stick.
A recycling facility wouldn’t have the means to process materials this size anyway.
So, they will need to go in your general waste bin.
6. Are Glow Sticks Biodegradable?
Glow sticks are not biodegradable because plastic and glass are not biodegradable.
While some of the substances in glow sticks – like hydrogen peroxide – are biodegradable, they do not leave the glow stick unless it is broken.
But, it is not advised to spill the contents of a glow stick since some of the substances are harmful and cannot be separated from any non-toxic components.
However, there have been moves to make more sustainable glow sticks, which are powered by bioluminescence, meaning the light is created by enzymes and water.
These glow sticks are said to be biodegradable in a home compost bin.