Top 10 Most Hazardous Chemicals in the Workplace

by Kate Onissiphorou

While many chemicals in the workplace may seem innocuous, some of them can pose a significant hazard. Knowing which ones are hazardous and how to handle hazardous chemicals properly can help to prevent injuries and any chronic detrimental effects. 

Here we look at the top 10 most hazardous chemicals in the workplace, including:

  • Arsenic
  • Lead
  • Benzene
  • Chromium
  • Toluene
  • Cadmium
  • Zinc
  • Mercury
  • Pesticides
  • E-Waste

What are hazardous chemicals

Hazardous chemicals are any type of substance that can potentially cause harm to living organisms, including humans, and the environment in general. Chemicals that are toxic, caustic or corrosive, carcinogenic, mutagenic or combustible are considered hazardous, especially if they’re not handled correctly.

Various countries and jurisdictions have specific regulations and classifications of hazardous chemicals. While these do not vary significantly, there are some minor differences and special cases. In the UK, for instance, hazardous chemicals are grouped into the following categories:

  • Explosive
  • Oxidising
  • Flammable
  • Toxic
  • Harmful
  • Corrosive
  • Irritant
  • Dangerous for the environment

Controlled substances are also classified as hazardous, albeit with varying degrees of danger. Similarly, medicines, such as antibiotics, can be hazardous without a proper prescription. 

How do you know if a chemical is hazardous?

Hazardous chemicals are easy to identify if you purchase them from a credible supplier. A label will be attached to the container and the supplier will also provide the appropriate safety data sheet (SDS) for that chemical. The SDS contains information about the chemical’s toxicity, volatility, combustibility, corrosiveness, and other potential hazards. An example of ReAgent's warning label

Non-hazardous chemicals are not required to have a SDS under the Work Health and Safety Act 2011. If you’re unsure about the potential hazards of a chemical product, always check with the supplier. If the product is hazardous, you’ll see an appropriate warning and corresponding pictogram on the label. Some examples of the pictograms commonly printed on chemical labels are shown below.

Pictograms of hazardous chemicals

As a precautionary measure, never expose a chemical container to high heat or touch its contents if you’re not sure whether it’s hazardous. If you have a chemical container with no clear label stored in your workplace, check the inventory record or ask an expert to identify the substance. Even common office chemicals such as printer ink can be potentially hazardous.

Here are some examples of hazardous chemicals that are commonly found in the workplace. You might encounter them directly or as a result of contamination. Some may also be part or traces of the old materials in the building such as asbestos.

      1. Arsenic
        Arsenic is a solid, non-metallic element that’s highly toxic to humans. Chronic exposure to this substance can harm the nervous system, cause organ damage and even cancer. Arsenic is found in some agricultural chemicals like pesticides, as well as wood preservatives. It’s also used in the production of glass and electronics.Illustration of what happens to the human body after contact with arsenic
      2. Lead
        Classified as a heavy metal, lead can cause brain damage, anaemia, kidney disease, and even birth defects. It was formerly a common component of paints and gasoline, although it’s now been largely discontinued as an ingredient in various products. That being said, lead is still found in electronics, roofing materials, car batteries, statues, and scuba diving gear.
      3. Benzene
        Benzene is a cyclic, aromatic hydrocarbon that’s typically a liquid at room temperature. Classified as carcinogenic, benzene can damage bone marrow and cause neurological defects. It can also compromise your immune system and lead to anaemia. You might be exposed to benzene if your workplace burns plastics or stores crude oil or pesticides.
      4. Chromium
        The element chromium is a metal that’s usually mixed with other metals to create alloys like stainless steel. It’s also commonly used as a chemical coating on metallic surfaces to prevent oxidation. Some of the health risks associated with chromium include asthma, respiratory irritation, and kidney damage.
      5. Toluene
        Toluene is a substituted aromatic hydrocarbon that can cause various health problems, including organ damage, dermatitis, anxiety, muscle fatigue, and dizziness. Toluene is often used as a paint thinner and nail polish remover. It’s also a component in explosives (TNT), glue, correction fluids, and stain removers.
      6. Cadmium
        Cadmium is a metal element commonly found in rechargeable batteries, as well as coatings and solar cells. Exposure to this metal can cause flu-like symptoms, lung damage, kidney disease, neurological problems, and cancer.
      7. Zinc
        Although zinc is an important trace mineral necessary for normal biological processes, it poses health risks in its elemental form. Some of these health problems include nausea and vomiting due to stomach problems, along with muscle cramps, headaches and diarrhoea. Zinc is often found in pipe organs, batteries, sunblock, medicinal ointments, and car parts.
      8. Mercury
        Elemental mercury is the only stable metal in a liquid state at room temperature. It’s often found in thermometers, barometers, vapour lamps, dental fillings, and vaccines. The most common health risk associated with this metal is neurological damage. Mercury can also damage internal organs such as the lungs, thyroid, and kidneys.
      9. Pesticides
        There are several types of pesticides, all of which can have detrimental effects on humans and the environment. As well as blisters and nausea, they can cause respiratory problems, Parkinson’s disease and cancer. Often used on farmland and in production plants, pesticides can be applied in liquid, solid (dust particles), and gas forms.A farmer spraying pesticides on crops
      10. E-waste
        E-waste, or electronic waste, includes all gadgets and electronic devices that are beyond repair. They’re largely solid electronic boards and components, but may also contain liquids and gases, such as those found in capacitors and lamps. Examples of electronic waste include televisions, fridges, microwaves, laptops, and mobile phones. These items contain a wide variety of materials such as plastics, lead, and refrigerants, which can pose a risk to the nervous system and DNA. Some types of e-waste can also cause cardiovascular diseases and kidney damage. An estimated 50 million tons of e-waste are produced globally every year.

        How to dispose of hazardous chemicals

        Chemical suppliers provide safety data sheets for the chemical products they manufacture and sell, which include information on how to dispose of the substance properly. The specific methods of disposal may vary from one type of chemical to another. 

        However, as a rule of thumb, hazardous chemicals should be kept in tightly sealed containers. They must not be exposed to high temperatures and they should also have the proper labels affixed to them. Disposal companies can provide professional disposal services for highly toxic chemicals.

Original post: Top 10 Most Hazardous Chemicals in the Workplace. No Republication or Redistribution allowed without written consent. Contact ReAgent Chemicals for more information.


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