Sept 27, 2016: What hidden toxic dangers are present in some common science fair projects?


School Days… School Days

Good old “Golden Rule” days.

School days … so much more than “reading, ‘riting, and ‘rithmetic” as the third line in the song “School Days” by Will Cobb and Gus Edwards (1907) suggests.  Our broad academic curriculums must teach students about their evolving world.  The knowledge explosion in the science and technology fields over the past 100 years has created a wealth of information for students to learn and absorb.  As pupils explore the scientific world, what latent dangers exist in the experiments that intrigue their shaping minds?  What potential perils could present a host of hazards as they prepare for their science fairs?  Let us look at a few of the conventional laboratory presentations commonly found at a majority of the schools’ science fairs today:

DISSECTIONS – Danger: Formaldehyde

Two of formaldehyde’s hazardous ingredients are formalin and methanol.  The effects vary with these ingredient’s concentrations and contact amounts.  Mild irritation to the skin, eyes, nose, mouth, throat, and lungs could result with low concentrations and trivial exposures.  Nausea, vomiting, coughing, wheezing, and dermal rashes could ensue.  These minor symptoms can be safely managed on site with just thorough decontamination. High concentrations or large ingestions are uncommon in the school setting, but could cause acidosis and severe injury to the eyes and lungs.   Usually, school exposures result from a dare to “kiss the frog” or “lick the pig” with no significant effects.

VOLCANIC ERUPTIONS – Danger: Sodium Bicarbonate and Vinegar

In small amounts the sodium bicarbonate (a base) and the vinegar (a weak acid) are ocular, dermal, gastro-intestinal, and respiratory irritants with nausea, vomiting, coughing, wheezing, and skin redness possible.  Minute exposures can be managed on site with thorough flushing and fresh air.  Significant exposures of sodium bicarbonate could result in hypernatremia, hypokalemia, hypocalcemia, and alkalosis.  Students with dizziness or weakness should be evaluated in the emergency department.  In general, exposures to these products are minimal, with burns from the heat of the chemical reaction causing the greatest concern.

ROCKET FUEL – Danger: AlkaSeltzer

While the fizz of the AlkaSeltzer and water combination can give a homemade rocket its lift, the AlkaSeltzer could be harmful if ingested.  AlkaSeltzer contains sodium bicarbonate and aspirin. Effects of large sodium bicarbonate ingestions were discussed in the previous section.  Aspirin ingestions could lead to metabolic acidosis, respiratory alkalosis, hypokalemia, altered mental status, pulmonary edema, and cerebral edema.  It is best to contact the poison control center if these tablets are eaten to determine the extent of potential toxicity that could develop.

MAGNETIC FIELDS – Danger: Magnets and Iron Filings

Magnets and iron filings represent foreign bodies.  Concerns regarding obstruction and choke arise when these substances are ingested.  One small magnet should pass through the gastro-intestinal tract without difficulties as long as no other magnet or metal product is consumed.  Combination consumptions could lead to bowel obstruction or perforation as the metals attract each other.  Iron from any filings that become lodged could be absorbed and possibly produce iron toxicity.  Ingestion of a magnet or the filings requires an X-ray to verify location, with repeat X-rays as needed to ensure complete product passage.

ELECTRICITY and CIRCUITS – Danger: Dry Cell Batteries

Dry cell batteries contain inorganic mercury.  Acute toxicity at the science fair environments is rare, but exposure to battery leakage could lead to irritation of the ocular, dermal, gastro-intestinal, and respiratory systems.  Prolonged or significant exposures could cause burns. Brief contact can generally be managed on site with thorough flushing.  Students with persistent symptoms of eye irritation, vomiting, or coughing should have a medical evaluation.

MEGAFOAM – Danger: Hydrogen Peroxide

Megafoam results from a hydrogen peroxide and yeast combination.  Yeast is not harmful, causing nausea and vomiting at most if ingested.  Hydrogen peroxide is an oxidizer.  Effects from hydrogen peroxide depend on the concentration of the solution, the exposure amount, and the length of contact. Solutions of < 10% concentrations produce irritation to ocular, dermal, gastro-intestinal, and respiratory systems.  Toxicity in these strengths is rare and typically requires only thorough decontamination. Burns could result if prolonged contact occurs; therefore prompt treatment is recommended.  Exposure to concentrations > 10% can be caustic, potentially causing severe injuries and ulcerations.  Ingestions of these solutions could create a gas embolism within the vascular system.  Contact the poison center for treatment recommendations, especially if a high concentration exposure occurs.


Methylene blue when added to milk shows the presence of aerobic bacteria.  Small exposures to methylene blue could irritate the eyes and stomach while causing a blue discoloration to the skin and mouth. Large exposure could lead to methemoglobinemia, especially for those pupils who suffer from G6PD.   In addition, methylene blue has MAOI activity and may interact with several medications, including: SRIs, SSRIs, SNRIs, TCAs, NDRIs, triptans, and ergot alkaloids.  Tiny exposures can be managed on site with thorough flushing and fresh air.  Individuals with large exposure or significant symptoms (ex: confusion or cyanosis) should be evaluated in the emergency department.

This synopsis is merely a brief overview of some potentially toxic dangers that might be present in a few of the science fair projects.  Hundreds of experiments exist, far beyond the abridged scope above.  Therefore, it is always important to call the poison center for treatment recommendations should any exposure occur during science fair preparations.

This question prepared by Cheri Wessels, RN, BSN, MBA, CSPI (Certified Specialist in Poison Information  Tennessee Poison Center


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Donna Seger, MD

Medical Director

Tennessee Poison Center

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