A Stink That Sparked Panic
Recently, residents of a British town thought disaster had struck when a strong “gassy” odor filled the street. Soon an engineer was on the scene, checking businesses one by one for a suspected leak.
The culprit? Not a ruptured pipe or faulty appliance, but the world’s most pungent fruit: durian. Popular in Southeast Asia, durian is infamous for its odor—so much so that in some countries it’s banned from public transport.
The issue was quickly resolved and everyone had a good laugh, but the incident highlights the importance of paying attention to odors in the lab. Your nose is an important safety device.
Understanding Chemical Odors: What Do They Signal?
Some smells are distinctive, others are deceptive, while many toxic gases are completely odorless. Here is a quick pocket guide to common lab smells:
- Gasoline-like: Benzene and other hydrocarbons. Potentially carcinogenic.
- Rotten eggs: Hydrogen sulfide. Even at low levels it can cause nausea, dizziness, and worse at higher concentrations.
- Bleach: Chlorine. Irritating to lungs and eyes.
- Urine-like: Ammonia. Corrosive to the respiratory tract.
- Fishy: Phosphine or arsine. Both highly toxic.
- Almond-like: Hydrogen cyanide. Deadly, though not everyone can detect it.
- Cabbage or onion-like: Sulfur compounds such as dimethyl sulfide or tert-butylthiol (used to odorize natural gas).
- Sweet or fruity: Organic solvents like ethylene or methanol. Can cause dizziness and long-term damage.
- Odorless: Carbon monoxide, radon, and others. Requires sensors for detection.
Smell is not always a reliable safety measure, but when present, it can provide crucial information.
Stench Chemicals: A Category of Their Own
Some compounds are so notoriously foul-smelling that they’re collectively referred to as stench chemicals. These include thiols (mercaptans), sulfides, amines, and butyric acid.
- Thiols, in particular, are familiar since they’re added to natural gas to make leaks detectable.
- Even trace amounts (parts per million) can trigger strong reactions, leading to false alarms, like the one in Britain.
Because of their impact on both lab workers and neighboring spaces, handling stench chemicals requires special odor control measures, such as:
- Always working in a fume hood.
- Using bleach traps to neutralize vapors.
- Keeping hood sashes low and using the smallest possible quantities.
- Proper waste management, including sealing contaminated items in labeled hazardous waste containers.
Safety Advice: Navigating Lab Smells
Whether amusing or alarming, smells in the lab shouldn’t be taken lightly. Follow these key guidelines:
- Waft, never sniff: Don’t stick your nose in the bottle—fan vapors gently toward you.
- Never work alone: If you’re overcome by fumes, someone needs to be there to help. If it's not possible for someone to be physically present, can someone be connected by videoconference?
- Use engineering controls: Fume hoods, traps, and ventilation systems exist for a reason.
- Take your colleagues' noses seriously: People have different smell sensitivity. Just because you can't smell it doesn't mean you shouldn't run.
- Be cautious with “harmless” smells: Even non-toxic odors can trigger asthma or allergic reactions.
- Assume the unexpected: If you can’t identify a smell, report it. Better safe than sorry.
Over to You
From durian to beta-mercaptoethanol, stinky experiences are a shared badge of honor among researchers.
What’s the worst smell you’ve ever encountered in the lab? And how do you and your team handle odor issues day-to-day? Let us know in the comments!