Firefighting and dermal poisoning

It is not just the flames. When firefighters rush towards a fire, their core fear may not be the unpredictability of the blaze itself. Rather it's the highly toxic fumes being created as complex chemicals burn.

This is no minor problem. Firefighters are dying from rare cancers up to 20 years earlier than the general public. Academics have found that firefighters face ‘a significant increase in the incidence of rectal, prostate, bladder and testicular cancers as well as mesothelioma and malignant melanoma in firefighters compared to the general population’. So, it is critical to understand how the poisons are being absorbed and how better to protect first responders.

It is absorption through the skin, as much as inhalation, that is the transmission mechanism causing increasing concern over the premature mortality of firefighters. Minute toxic contamination molecules from gases and solid particles are known to pass through the thinner layers of skin on our scalps, necks behind our ears and areas such as underarms and tops of the legs. Researchers have found that it is this dermal exposure which presents a high cancer risk with current PPE.  

Dermal absorption occurs when a chemical or chemicals go through the skin and travel into the body. Many chemicals used in the workplace can damage organs if they penetrate the skin and enter the bloodstream.  Absorption can occur through direct contact with the chemical itself i.e. in liquid form and in the case of fires, from toxic gases and vapours which are much smaller than actual physical particles and dusts.

The volume of cancer-causing chemicals released in serious fires is fearsome. Professor Anna Stec told the Grenfell Fire inquiry that, a month after the blaze, the amount found on the ground near the North Kensington block was still 160 times normal levels.  

Industrial fires involving chemicals and risky flammables might be seen as the more obvious threats. But escalating incidents of wildfires linked to climate change cannot be ignored. Last year, Marsden Moor in west Yorkshire saw its first outbreaks as early as February and they kept recurring. An assessment of wildfires published in 2020 of incidents that broke out at Saddleworth Moor and Winter Hill two years previously found that five million people had been exposed to levels of dangerous particulates - known as PM2.5 - for at least one day. The levels exceeded World Health Organization limits. For hundreds of firefighters at the scene, the risks were higher still. (https://www.bbc.co.uk/news/uk-england-manchester-52208610)

When ablaze, peat fires emit significant levels of nitrogen oxides (NOx) and soot, while in the smouldering stage they emit high levels of volatile organic compounds (VOCs), methane (CH4), much more carbon monoxide (CO) and particulate matter (PM). (Turetsky et al 2015) [https://iopscience.iop.org/article/10.1088/2515-7620/ab7b92/pdf]

Natural resins, rosin and sap from burning moors create dangerous hazards on combustion such as formaldehydes. Wildland fire fighters are particularly vulnerable as current PPE is often based on basic flame-retardant coveralls. These are designed to protect against airborne embers and worn typically over station wear, or basic underwear.

Wild land fire is basically hot and arduous work and not conducive to any additional heat burden from PPE. If firefighters minimise their equipment, they risk maximising their potential exposure. Many wildfires are also attended by volunteers, which is particularly prevalent in countries with large swathes of woodland and vegetation. Australia for example has one of the largest numbers of volunteer registered fire fighters in the world.    

The dangers associated with encountering carcinogenic chemicals through fire effluent and smoke is set out in detail in a report by Anna Stec and her team at the University of Central Lancashire (UCLAN) - https://www.fbu.org.uk/publications/minimising-firefighters-exposure-toxic-fire-effluents. Their work gives an insight into the torrent of toxins pouring out from a major fire. It is intuitive that effective masks to reduce the inhalation risk are critical. Our lungs are extremely delicate, the fumes laced with potent carcinogens and deadly dusts.

But are first responders getting the protection required relevant to the kind of threat firefighters and emergency workers face?

The Swedish Civil Contingencies Agency has found that current firefighters’ PPE is not designed to prevent combustion gases from coming into contact with the body. There is also potential diffusion of toxic gases/vapours through firefighters’ turn-out jackets (Mayer et al).  This in turn can defuse through the skin and in some cases, such as exposure to Polycyclic Aromatic Hydrocarbons (PAH’s), cancers can result. This explains why the WHO has declared cancer to be the number one health risk to firefighters.  

The prevention of such hazards are critical to health and wellbeing and is achieved by special forms of Personal Protective Equipment (PPE) produced as protective garments often involving a number of fabric combinations working as a ‘system’.  

This is where my business Nonwovenn is operating. We are a specialist materials manufacturer focused on harm reduction. Our products include the activated carbon masks used by Deliveroo to reduce inhalation risks for their cyclists and by Samsung to protect workers micro-welding mobile phones.

We also make the material for the protective suits used by security force personnel dealing with hazardous chemical and other threats. The key to the fabric is not just its remarkable capacity to prevent the toxins from reaching the skin. It is also the usability of the materials such as overgarments.  

Older types of PPE, are simply far too heavy, making fire-fighting much harder and reducing the endurance for tackling the blaze. Firefighters simply cannot spend enough time at the scene due to the heat stress caused by unwieldly PPE. Tied in with this is perspiration. Continual exertion creates energy-sapping heat for those working in hazmat suits. Even more so for firefighters. Whether they are operating in confined spaces inside a building or tackling wildfires during a heatwave, their protective clothes have to keep them as cool as possible. Research has shown that as skin temperature rises then absorption into the body from toxic materials increases also. It is understood that for every 5c increase in skin temperature, absorption of toxins via the skin can increase_ by 400%.

Proper functioning PPE has to be appropriate to these risks. Material must be not just lightweight and able to minimise thermal burden, but also maintain air permeablity. This is what our ground-breaking designs deliver - they allow air flow and evaporation from the skins surface to transport heat and moisture away, utilising the bodies own natural mechanisms of heat regulation.

Our latest fabrics are half the weight of standard ones, fully air permeable and able to protect against hazardous chemicals and off gases from the effect of combustion without compromising the ability of the firefighter to perform their tasks.

They also absorb harmful chemical vapours before they come into contact with a person’s skin, thereby mitigating the vapour threat. Due to their effectiveness, these fabrics made in Somerset in the UK are used globally by both military and civil responders alike.

The potential risks do not end when the fire is put out either. A variety of dangerous compounds released by the fire can remain on their suits. Science is helping to grow our understanding of these invisible threats. This is why Nonwovenn is developing material standards for the next generation of firefighting suits, at the request of international standards bodies. We are factoring in the need to protect against occupational hazards such as combustion chemicals, whether structural fires in buildings, or wildland or long-term exposure to wood and brush fires.

The work on new materials standards is progressing swiftly through the different international technical committees that support the International Standards Organisation (ISO) publications. The draft standards are currently under review by technical experts. 

Knowledge and understanding of dermal and vapour threats has grown very quickly since Prof Anna Stecs initial report. We believe that Nonwovenn’s Pro-Intelligent materials and fabrics are reducing the risk of decades of sickness and ill health caused after exposure to toxic chemicals, vapours and gases present from burning fires.

Commissioned to carry out testing in accordance with EN 16523-1 and EN 16523-2, our fabrics were assessed as effective against two representative Polycyclic Aromatic Hydrocarbons (PAH’s), namely Benzene and Naphthalene. These chemicals were chosen due to their volatility and relatively small molecular size and deemed to be amongst the most difficult to protect against.

We do not know when the world’s firefighters will face their next Grenfell Tower - or 911. But we are proud that our firm based in Somerset is on the cutting edge of making these incidents more survivable for first responders and clean-up workers and reassuring firefighters going out to moors and forests that they have got the best protection available.

David Lamb is chairman of Nonwovenn. For more information, visit https://nonwovenn.com/