WILL LITHIUM BE THE NEXT METAL POISONING?
By Guy LeNoir – Director / SOS-Switched Onto Safety
What is Lithium?
Lithium is the lightest of metals, is an alkali metal and like all alkali metals, it is highly reactive with strong oxidants, acids and many compounds including concrete, sand (silica) and of all things, asbestos. Posing as a significant explosion and fire risk.
In its natural state it is an unremarkable product contained in petalite, lepidolite and spodumene ores and also subsurface brines.
Lithium in various forms is used for a variety of things including glazes, aluminium products, batteries, lubricating greases, metallurgy and other chemical and industrial uses.
Lithium is also used from a medical perspective. This came about from people drinking from ‘healing wells’ which created curiosity from a medical perspective leading to its identification in managing mental health issues like bipolar and schizophrenia.
So where am I going with this, well:
My concern is that with the increased mining and processing of this product and the methods used may in turn create a deleterious exposure if it is bioactive. I also ask the question, does this exposure to the product increase the levels of Lithium in those persons taking Lithium for medical purposes? I am concerned that we do not know the full implications from dust inhalation exposure.
In researching this product and the mining / processing of it, I have been able to find very little in epidemiological information in relation to dust exposure. I have been able to identify Temporary Emergency Exposure Levels (TEEL’s) but no Occupational Exposure Levels (OEL’s) ie Time Weighted Averages (TWA) / Threshold Limit Value (TLV), other than in medical practice, for this product.
I have been able to find information in relation to its medical use, but next to nothing for occupational exposure. However, a lack of data does not mean something is safe, it just means we have a lack of data.
Up until now we have produced Lithium from brine, but with the growing knowledge of its uses, there is a commercial demand for it to take us in to the future. Hard rock mining is now becoming commercially viable, thus bringing with it additional potential health hazards. What are the long-term effects? What is the effects of exposure for those already utilising Lithium for medical purposes?
For mining to occur, it is a requirement for companies mining Lithium to develop, amongst other plans, Health Hazard Management Plans and Radiation Plans. One would expect that critical controls to prevent reactivity would have been built in during the Safe Design processes. However, has dust exposure been given critical thinking from a respiratory perspective. It is important that critical controls don’t only focus on items that seem to have an immediate health and safety impact but rather to think more broadly to encompass controls needed to prevent impact in general. This is important as we do experience personnel becoming blasé in respect to those controls that are not identified as ‘critical’. Remembering the resurgence of ‘black lung’ (coal workers pneumoconiosis) cases. Remembering, if there is over exposure, that effects such as pulmonary oedema is not immediate, but continues to develop even after a person has finished their shift.
The question is then raised, within the Lithium mining companies HHMP, what are they stating they will measure and what will they measure against? Just because we don’t have any OEL data, does not mean we don’t have any risks. It means we just don’t know what the safe levels are.
When looking at Safety Data Sheet’s, they clearly identify that you shouldn’t breath dust or mist due to the acute, chronic / latent affects it has, however they are silent on identifying the OEL’s. The SDS’s appear to indicate that airborne concentration must be maintained as low as is practically possible and OEL must be kept to a minimum. However only TEEL 1, TEEL 2 and TEEL 3 limits are available (NOTE 1).
My thoughts are that Lithium Mining Companies have a further duty to the industry / employees / community to define as far as possible adverse effects and at what level they start happening. Are epidemiological studies being conducted to identify OEL’s? If so, is this being conducted from an individual company perspective or an industry collaborative approach? I would be very interested in being involved with Lithium companies to investigate this further from an industry collaborative approach.
- TEEL-3 is the airborne concentration (expressed as ppm [parts per million] or mg/m3 [milligrams per cubic meter]) of a substance above which it is predicted that the general population, including susceptible individuals, when exposed for more than one hour, could experience life-threatening adverse health effects or death.
- TEEL-2 is the airborne concentration (expressed as ppm or mg/m3) of a substance above which it is predicted that the general population, including susceptible individuals, when exposed for more than one hour, could experience irreversible or other serious, long-lasting, adverse health effects or an impaired ability to escape.
- TEEL-1 is the airborne concentration (expressed as ppm or mg/m3) of a substance above which it is predicted that the general population, including susceptible individuals, when exposed for more than one hour, could experience notable discomfort, irritation, or certain asymptomatic, nonsensory effects. However, these effects are not disabling and are transient and reversible upon cessation of exposure.