White Paper
Alarming Toxicity in Chemical Lighting
Hidden chemicals, carcinogenic byproducts, broken laws, regulatory loopholes, and millions of people impacted.
Most people in the world have used a glow stick at least once. I'm guessing yourself included.
Glow sticks are used on every continent of our planet - even Antarctica! Used for everything from essential safety lighting, deep sea signalling, commercial fishing lures, fun at concerts, and even in space, glow sticks pop up everywhere. We estimate well over a billion are used every year.
Glow sticks or ‘light sticks’ were originally developed by the US Military, and were once powered by now-illegal chemicals. Although regulations have forced manufacturers to develop different formulas, there is little to no evidence to support that these formulations are as safe and non-toxic as glow stick companies promote - in fact there is increasing evidence to the contrary.
A growing body of scientific literature is finding shockingly toxic results after exposure to post-activation glow stick liquid [2,3,4,5,6], which points to the production of harmful byproducts. Even worse, consumer reports found that most commercially available glow sticks contain unreported ingredients - outlawed and hidden chemicals were discovered in 17/20 glow sticks surveyed [6].
From the toxic constituents in their formulas, to the sneakily loopholes that allow companies to label glow sticks as ‘safe and non-toxic’, to the alarming aftermath of their use, and the staggering number that are used every year. This examination underscores the need safe and sustainable alternatives.
Note on language used in this report:
If you search online for ‘glow stick chemistry’ usually the term ‘chemiluminescence’ is used. By definition, chemiluminescence refers to ANY chemical reaction that creates light. The reaction that occurs in glow sticks is just one type of chemiluminescence. So in order to keep definitions straight, we will use the terms ‘chemical light’,‘glow stick formulations’ or ‘glow stick fluid’, to distinguish this topic from the more general term ‘chemiluminescence’. Most chemiluminescence is very dim - it took a lot of work and intensive chemistry to get glow sticks so bright.
1. Original formulations created ‘Agent Orange’ type dioxins as a byproduct - evading detection
Historically, the first glow sticks ever made were horrifically dangerous. Back in the 1970's they contained ‘polychlorinated oxalate esters’ that upon reacting with peroxide had the possibility to form TCDD (tetrachloro dibenzo-para-dioxin), the worst known dioxin and what made the now-illegal chemical weapon, Agent Orange, so dangerous [1]. This molecule is made as a byproduct of the reaction, meaning that tests on the formula pre-activation would show no sign of a dioxin. It is after the glow stick is activated that these dangerous byproducts are made, and part of how dangerous chemicals in these formulas went unnoticed.
Dioxins are persistent, carcinogenic, endocrine disrupting molecules. Short-term exposure to dioxins can cause skin lesions and impaired liver function. Long-term exposure is linked to birth defects, impaired immune system, alterned developing of the nervous system, the endocrine system and reproductive function. It is a persistent pollutant that can impact generations of people after exposure [1].
The first 'superfund site' in the United States (places considered too damaged to restore) was caused by TCDD contamination, which became known as the Love Canal Disaster. Families were forced to flee their homes, after a drastic increase in rare cancers was linked to environmental TCDD exposure. This place remains a ghost town to this day.
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Agent Orange survivors marching for awareness and support - many here are living with the long term impact of dioxin exposure.
Regulations banning the use of these chemicals pushed glow stick companies to develop alternative formulations, and this is what lead to the ‘modern’ formulations. The changes are very small on a chemical level, and we are taking steps to fully confirm that no dioxins are forming - research that as far as we can tell, was never fully completed, or is not publicly available. Although different molecules will have different mechanisms of action, just because it is not as selective for what TCDD targets, does not automatically mean they are any less dangerous.
The current standards in glowstick formulations use CPPO - Bis[2,4,5-trichloro-6-(pentyloxycarbonyl)phenyl]oxalate and TCPO - bis(2,4,6-trichlorophenyl) oxalate, which are expected to react with hydrogen peroxide, and are still considered to be ‘polychlorlinated oxalate esters’. Most public information on this will focus on the high energy intermediate (dioxetanedione) that creates two molecules of CO2 and a photon, but the remaining moiety is unaccounted for: the two chlorinated aromatic molecules from the starting material. It is the chlorinated species which are most likely to create any number of dangerous byproducts. There is growing evidence that has found surprising toxicity, discussed in section 2. The results from these studies is becoming expected, as authors noted in this paper.
It is noteworthy that there is no evidence publically available that strictly confirms that dioxins are not formed by the new formulations. It seems that glow stick companies would be promoting this chemical safety data as widely as possible if the chemistry was conclusive.
There may be a mechanism that produces dioxins as a byproduct of a reaction with the new chlorinated molecules in new formulas. We are working to investigate this matter with help from academic partners, as this has yet to be characterized.
2. The byproducts from modern formulas found
to cause similar toxicity and damage
Just like the original formulas
Although there is a lack of comprehensive or transparent information about the new glow stick formulations, there is a growing body of evidence that commercially available formulas are much more toxic than marketed.
In 2014, one of the first pieces of academic literature was published that independently studied the toxicological impact of chemical light fluid on cell lines in Nature Science Reports, entitled “Luminescent Threat” [2].
6000 glow sticks were collected off a beach in Brazil, where thousands of light sticks from the fishing industries washed up on their beaches. This groundbreaking research raised the alarm on the modern glow stick fluid formulas. Rather than being safe and non-toxic as marketed, results showed acute toxicity in the post-activation fluids, meaning that toxic byproducts are forming. Cytotoxicity (complete cell death) occurred which made the effects on genetic mutations difficult to study, as the cells completely died. After being diluted 30,000 fold, it was found that exposure to glow stick fluid caused genetic mutations in human cell lines[2].
“On the beach, the reaction products, catalyst, and solvent exposed to sunlight for long periods of time may greatly contribute to the observed increase in LS toxicity. Because humans are mainly exposed to the [activated] light stick products, care must be taken when attempting to extrapolate toxicity data from the initial components to the spent and sun-exposed mixtures.”[2]
It was evident that byproducts of the reaction, especially after being lost at sea for potentially years at a time and exposed to UV rays and temperature fluctuations, caused the observed toxicity. Since the publication of this 2014 paper, a growing body of evidence is further confirming and expanding on their results [3,4,5,6].
The “spikes” in the images above correspond to the chemical mix of the formulas analyzed. In the second graph, which is from a glow stick collected from a beach, new ‘spikes’ have developed. The 4 day old formula does not have this peak. This indicates that multiple byproducts not present in the initial reaction have formed over time.
“When [glow stick] solutions are mixed, TCPO reacts with hydrogen peroxide, yielding 2,4,6-trichlorophenol and the highly energized 1,2-dioxetanodione intermediate, whose DPA-activated decomposition to CO2 places the fluorescer in the fluorescent state. The chlorinated product 2,4,6-trichlorophenol is listed as reasonably anticipated to be a human carcinogen by the US National Toxicology Program, as a probable human carcinogen by the US Environmental Protection Agency15, and as a possible human carcinogen by the International Agency for Research on Cancer.” [2]
These findings directly fly in the face of glow sticks being labeled as ‘non-toxic’ and 'safe', and posion control centres advice to treat exposure casually. As outlined in Luminescent Threat, once “chlorophenols are absorbed through ingesting/biting, skin contact, and or the fumes breathed in, both local and systemic effects are expected. After absorption, major concentrations of chlorophenols have been reported to be found in the kidney and liver for up to 20 days. Chlorophenols are liver tumor promotors [2].
Another scientific paper investigated a step further into the impact of time on the toxicity of the formulas, and found that exposure to formulas that were 1 year old showed 2x more toxic effects than exposure to glow stick formulas which had just been activated [3]. This research also tested the exposure to the separate components of non-activated glow sticks and found much lower toxicity in the separate fractions than was found in the fully mixed formula. Again, it was suggested that the increase in toxicity over time could be attributed to the creation of byproducts of the reaction, as mentioned in the section above. This is of particular concern, as the byproducts of the chemiluminescence reaction are not outlined in basic chemistry of chemiluminescence consumer resources.
More recent studies have identified a myriad of harmful byproducts, including 2,4,6-trichlorophenol and polychlorinated dibenzodioxins, known for being carcinogenic and impacting normal development [4].
Conluding their report, the authors of Luminescent Threat couldn’t summarize it better: “An urgent need exists to adequately manage the discarded LS and to foster awareness about the health risks that may result from exposure” [2].
3. Laws have been broken - dangerous chemicals found in glow sticks labeled 'non-toxic'
One challenge of testing commercial glow stick formulations or making specific claims that could relate to a specific company or formula, is that the components of the formulas are not required to be listed on glow stick packaging. Thankfully, the Danish Ministry of the Environment conducted a consumer report to determine what was actually inside 20 different glow sticks tested [7].
Europe requires the self-reporting of chemicals in consumer products as part of their REACH regulations [9] even if they are not listed on the packaging. As REACH compliance is a self-reporting process, investigations are part of testing proper adherence to these regulations. The Danish Ministry of the Environment launched an investigation into glow stick products, and the findings were shocking. Illegal chemicals such as dibutyl phthalate were found, and only 3/20 products surveyed properly self-reported the chemicals used in their formulations, and 17/20 had different and often more dangerous formulations than reported [7].
"The use of dibutyl phthalate in glow sticks considered to be toys is a violation of the law." stated the Danish Ministry of the Environment, after finding dibutyl phthalate in glow sticks marketed towards children.
Appendix 9 in the Danish report found concerning marketing tactics used to target use for children. For example, one brand had children on the packaging, despite explicitly having written "not for children" on the back of the packaging [7]. That is giving some alarming mixed messages.
Glow sticks are often thought of as kids toys - and promoted this way. An alarming trend of ‘sensory glow stick baths’ is growing in popularity with parents. Products have been found featuring small children playing with glow sticks, even when marked ‘not for children’.
There are even some lolipops available that use glow sticks as the handle while the candy is bit into.
This is a flagrant disregard of childrens safety.
4. Loopholes that allow companies to market glow sticks as 'safe' are also being broken
Over 2 million exposure events in France alone
Most people are unaware of the potential hazards posed by these products and most poison control centres follow this narrative. As seen on many poison control websites - their recommendations are based on exposure to the listed reagents in glow sticks (such as hydrogen peroxide), not the actual components or byproducts of the reactions, which we know now are much more dangerous. This messaging is aided by the glow stick manufacturers themselves, who market their products as safe and non-toxic. They get away with this likely due specific regulatory language around the ‘accessibility’ of toxic components of a product.
These types of apparent loopholes recently came into the zeitgeist in the United States, when the viral Stanley cups were found to contain lead. The manufacturers were not breaking any laws, even though Stanleys are used to hold hot liquid meant for consumption (!), because the parts containing lead were deemed inaccessible and therefore not breaking any laws.
The same type of loophole is how glow stick companies can market their product as safe and non toxic. For example, currently a child's toy can be marked as “phthalate-free” if the components that contain phthalate are deemed to be inaccessible by the ‘strength of an average 8 year old’ [10].
For glow sticks, we strongly disagree that the toxic components are completely inaccessible, and data supports this. In France, over the course of 1999-2020, 2,029,714 exposure events were recorded. Just in France!
Children between 1-4 years old constituted 50% of the exposure events, often due to biting through the plastic tube [7].
We do not support the claim that the chemicals within glow sticks are ‘inaccessible’ - as millions of calls to poison control centres worldwide prove. Glow sticks components are EASILY accessible, and therefore are once more in violation of the law.
5. Well over 1 billion units every year of non-recoverable, toxic, plastic waste
Once the light fades, there is no good waste management of a used glow stick. The best case scenario is they are transferred directly into a dark, sealed box (to prevent UV exposure), and disposed of as hazardous waste. This is not currently standard practice.
Due to the chemicals inside, mixed with broken glass, and difficulty in post-use processing (would require cutting open, safely removing the liquid and glass, and washing the plastics) - no recycling center accepts glow stick waste. The entire product is non-recoverable waste.
Unfortunately many glow sticks do not even make it to landfills. This issue is what caused some of the original investigations into glow sticks in Brazil, where use of glow sticks as a pelagic attractant (fishing lure) results in thousands of glow sticks washing up on local beaches. For that paper, 6000 glow sticks were recovered from beaches [2]. A similar issue has been monitored in Australia by the Tangaroa Blue foundation, who has collected over 2.4 million glow sticks from Australian beaches over the past 20 years [8]. This is waste from just one industrial application of glow sticks.
Glow sticks are a standard part of military practices, and there are records of US camps getting reprimanded for not collecting all the glow sticks left behind.
For Coast Guard applications, glow sticks are used to help find someone lost at sea - glow sticks will be thrown in the water one after the other to create a ‘cookie crumb’ trail to follow back to the person as the currents pull them away.
Overall, many glow sticks are not ever properly recovered, and as they remain in the environment, become more toxic over time until one day releasing their contents into the environment. We estimate that well over 1 billion glow sticks are made every year, with the plastic and chemical waste remaining in the environment forever. This represents 10.6 million litres of these dangerous chemicals entering our environment, getting into our waterways, and harming the health of every living thing they come into contact with.
Industrial applications require the use of non-electric lighting
While the use of glow sticks persists, efforts to mitigate their environmental and health impacts are being investigated. Innovations such as LED alternatives and biodegradable materials offer promising avenues for reducing reliance on chemically-powered glow sticks. However, widespread adoption of these alternatives requires concerted action from manufacturers, consumers, and policymakers, and many available technologies have significant drawbacks or simply will not work to replace glow sticks.
Unfortunately, for many situations, LEDs are not a viable alternative, especially in industrial use cases. As outlined in the Chemical Light Stick Source Reduction Plan, by Tangaroa Blue and Ocean Watch Australia, use of glow sticks or “light sticks” is often required [8].
For many applications, a non-electric, non-explosive, non-battery powered, instantaneous activation, and inexpensive light source is truly the best option, which is why the use of glow sticks has continued to the present day, even with inexpensive battery powered LEDs being widely available since the 1990s.
Glow sticks are referred to as 'chem lights' or 'light sticks' in industrial settings, and are chosen for their cold-light, storage life, low cost, and ability to generate light without an explosion risk.
Chemical lighting, with all its flaws, is still incredibly useful. Chemical light was originally developed for military purposes as no heat is created by the reaction. A light source that creates no heat signature is incredibly useful for covert operations. Also, as there is no electricity needed, there is no risk that the activation of a glow stick will spark an explosion. This is useful when handling explosives, and also in the event of a gas leak. Glow sticks are currently the only recommended light source to use after an earthquake or similar disaster, when a broken gas line could cause significant risk of an explosion if electricity is used.
For underwater use, glow sticks can handle significant pressure, and if one breaks, it is not a huge cost unlike most underwater rated LEDs.
At the conclusion of their thorough chemical light stick reduction plan investigation in 2021, the Australian government concluded that there were no available solutions to this issue. They outlined what would solve the problem - a non-toxic and marine biodegradable glow stick alternative. One that had the same performance as chemical light, but would quickly degrade in the environment and would pose no risk to human or marine life [8].
The solution would need to be inexpensive, easy to use, and basically a rebuild of current glow sticks with completely redesigned materials and chemistry. In the report the writers wondered if something could be done with bioluminescence - how living creatures create light in their cells - something often seen in marine species.
6. New technology built to solve this problem
Lux Bio Lume - a marine biodegradable / home compostable glow stick alternative powered with bioluminescence, engineered to address all concerns with the chemical light industry
This is what our company, Lux Bio, has set out to do. In 2021, Lux Bio was founded and with the support of an incredible team, we have developed a breakthrough in the field of cell-free bioluminescence, meaning we have created a completely non-toxic luminescent system. We genuinely love the magic and curiosity that chemical lighting inspires. We even found out that the whole chemical light industry was originally inspired by bioluminescence - the technology just didn't exist before to do what we are doing. So now that incredible advancements in the field of biotechnology have made this possible - its time to go back to what inspired the industry from the beginning. We want everyone to have a safe and sustainable option, for everything from birthday parties to military applications, and beyond!
At its core, bioluminescence is the result of an enzymatic reaction. Our bioluminescent formulas are based on these incredible enzymes, which we can grow in our lab! The bioluminescence reaction requires NONE of the chemicals which are used in glow stick fluid. We simply mix our formula in water and the reaction takes place.
With the support of incredible advancements in the biomaterial industry, we are able to encase this reaction in certified marine biodegradable materials and home compostable packaging. This means that if our glow sticks end up in any environment, from the ocean, to a forest floor, microbial activity will quickly compost the materials. Everything becomes microbe food!
We have learned through this process that although science is challenging, these type of advancements are readily possible. Every product that you see in the store that is packaged in plastic is only done so because it is cheaper for the company producing it to keep using plastic, or to keep using harmful chemicals.
We are dedicated to providing an entirely new class of single-use glow sticks to the world - as an example of what can be done across every industry. If we can make compostable, non-toxic, beautiful glow sticks - what can’t we do? So often the changes we need to see in the world are only blocked by corporate greed - not because amazing technologies are impossible. In fact, many are already solved, and are struggling to find their foothold in the market.
It is hugely costly to start a materials company - from the R&D to figuring out how to manufacturer it, to building new production lines and facilities, and trying to find customers willing to buy something more expensive in the beginning to help bring the scale needed to bring costs down. Unfortunately this is the path new materials need to take, while huge corporations are buying the cheapest, most dangerous materials, making massive profits, and getting away with harming people and the planet.
This is what we are up against.
So for every one of you who helps share our work, share this report, buys our replacements, just know that you are an essential part of us having any chance of changing this industry. Thank you so much for making it this far - lets change this!
Holding an early LUME prototype while overlooking the Vancouver city line.
Now you know too. Lets change this together.
There's more!
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Share this report with your friends, families, and colleagues →
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Collect any glow sticks you find while out and about (once you start looking they are EVERYWHERE) and send them to the Glow Stick Initiative - a non profit who is raising awareness about the glow stick waste issue: www.theglowstickinitiative.org
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Support Lux Bio - one of the best ways to change something is to create something better. More than raising awareness, together we can make sure that glow stick companies, the industries that rely on glow sticks, and the millions of people every year who use these fun, but dangerous glow sticks still has a light they can rely on.
References
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Environmental fate and bioavailability of Agent Orange and its associated dioxin during the Vietnam War. https://pubmed.ncbi.nlm.nih.gov/15603524/
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Luminescent threat: toxicity of light stick attractors used in pelagic fishery. Nature Science Reports. https://www.nature.com/articles/srep05359
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Lightsticks content toxicity: Effects of the water soluble fraction on the oyster embryonic development. Chemosphere.
https://www.sciencedirect.com/science/article/abs/pii/S004565351500521
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Skin irritation and histopathologic alterations in rats exposed to lightstick contents, UV radiation and seawater. Ecotoxicology and Environmental Safety.
https://www.sciencedirect.com/science/article/abs/pii/S0147651309001055
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Lightsticks cause adverse effects on behavior and mortality of marine mysids Promysis atlantica. Latin American Journal of Aquatic Research.
http://www.lajar.cl/index.php/rlajar/article/view/vol49-issue4-fulltext-2651
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Chemical Contents of Disposed Light Sticks Affect the Physiology of Rocky Crab Pachygrapsus transversus and Gray Shrimps Litopennaeus vanammei. Bulletin of Environmental Contamination and Toxicology.
https://link.springer.com/article/10.1007/s00128-021-03321-5
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Survey and Health Assessment of Glow Sticks. Danish Ministry of the Environment.
https://www2.mst.dk/Udgiv/publications/2013/08/978-87-93026-41-4.pdf
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Chemical Light Stick Source Reduction Plan
https://www.tangaroablue.org/wpfd_file/owa-source-reduction-plan-professional-fishing-related-light-sticks-final-version/
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EU’s new rules to prevent harmful chemicals in childrens toys
https://www.euractiv.com/section/health-consumers/news/eus-new-rules-to-protect-children-from-harmful-chemicals-in-toys/
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US manufacturing regulations surrounding accessibility to pthalates in childrens toys
https://www.cpsc.gov/Business--Manufacturing/Business-Education/Business-Guidance/Phthalates-Information