Is tungsten harmful to humans?

As with other heavy metals, there are some concerns relating to the harmfulness of tungsten – specifically to the ongoing health of workers exposed to tungsten, in various forms, as part of their day jobs.  

These health concerns are centred around a selection of working hypotheses that tungsten exposure can cause poisoning, cancers, or even generalised mortality. 

But is this something we need to be worried about? Or is tungsten safe to use? 

Tungsten poisoning 

Acute tungsten poisoning 

The most common route of acute poisoning is ingestion, but it can also include inhalation, injection, and skin/eye contamination.

Acute tungsten poisoning is extremely rare and visible in high levels after toxicological analysis of blood, urine, hair, and nails. 

It can incur a range of physical symptoms, including:

  • Acute nausea 
  • Seizures 
  • Clouded consciousness leading to a coma – with evidence of encephalopathy (brain dysfunction)
  • Hypocalcaemia – when the blood contains too little calcium 

Gradual symptomatic recovery can take anywhere from a few weeks to 5 months, but it depends on the patient and the amount of tungsten they have been exposed to. 

 Chronic tungsten poisoning 

Most commonly stemming from embedded tungsten shrapnel or breathing in the dust formed from the manufacture, utilisation, or maintenance of hard metals like tungsten, chronic poisoning will likely come from longer-term exposure.

Chronic poisoning can reportedly: 

  • Double the odds of a reported stroke 
  • Show evidence of mild-to-moderate neuropsychological impairment – particularly memory function
  • Display increased risks of cancer in the lungs of those exposed (see below for more information).

Tungsten is a carcinogen? 

Animal studies so far have concluded that long-term exposure to tungsten can be carcinogenic, as identified by a under the National Toxicology Program by the Center of Disease Control and National Center for Environmental Health. 

The overall conclusions, with respect to the carcinogenic potential of sodium tungstate at the exposure concentrations, are as follows:

• There was no evidence of carcinogenic activity of sodium tungstate dihydrate (ST) in male rats.
• There was equivocal evidence* of carcinogenic activity of ST in female rats.
• There was equivocal evidence of carcinogenic activity of ST in the male mice.
• There was no evidence of carcinogenic activity of ST in the female mice. 

Equivocal evidence of carcinogenicity is concluded when the studies are interpreted as showing a marginal increase of neoplasms that may be chemically related.

Tungsten causes mortality? 

Happily, researchers in human studies in 2017 found no evidence that duration, average intensity, or cumulative exposure to tungsten, cobalt, or nickel, at levels experienced by the workers examined increases:

  • Lung cancer mortality risks
  • Mortality risks from any other causes of death.

Overall, then, while early animal research suggests that long-term exposure could be carcinogenic – or even harmful in general – much more research is needed to determine whether this is relevant to humans.

Especially when the benefits of this impressive metal make it so essential in industries across the globe. 

The far-reaching benefits of tungsten

As a unique refractory metal, tungsten is utilised in a huge variety of applications, from alloys to aeronautics, and from electronics to fabrication. 

So, while the health and safety of workers should be at the forefront of concerns, safeguards like rigorous PPE and safety procedures mean that it remains perfectly safe to utilise tungsten-based materials. 

Allowing us to access the benefits of tungsten – which include but are not limited to: 

  • Increased safety compared to other metals 

When compared to elements like lead, tungsten is a much safer alternative that has (so far) not demonstrated a sure link to detrimental health effects. 

  • The Technical Committee to the Tungsten Consortium have limited concerns 

According to EU REACH regulations, tungsten and tungsten substances were not given hazard warnings – except for:

  • Ammonium metatungstate and sodium tungstate – which are harmful if swallowed.
  • Tungsten powders (0.6 -9µm) that can be flammable or self-heating.

Demonstrating the safety of most tungsten materials.

  • Environmental advantages

Tungsten has many benefits for the environment, including: 

  • Improving yields of desirable components in gasoline while also reducing environmentally harmful by-products, like sulphur and nitrogen. 
  • Proven use as a catalyst for the reduction of nitrogen oxide from exhaust gases.
  • Plentiful clean energy applications, including in photovoltaic cells (solar PV) and fuel cell technologies.

Among the many, many other benefits of tungsten. 

Need trusted tungsten products?

If you need tungsten or tungsten metal products, like tungsten wire, be it for manufacturing, research, or other specialist applications, why not consult Special Metals?

With over 115 years of experience with refractory metals, there isn’t much they can’t help with – so get in touch to enquire about tungsten metal parts and fittings.