Biological monitoring for Isocyanates

Organic diisocyanates are a significant occupational health problem.

They are respiratory and skin sensitizers and a major cause of occupational asthma in the UK. The most common are hexamethylene diisocyanate (HDI), toluene diisocyanate (TDI), isopherone diisocyanate (IPDI) and methylene-diphenyl diisocyanate (MDI) in decreasing order of volatility. HDI and IPDI are used for varnishes, coatings and two-pack spray paints used in motor vehicle repair. TDI and MDI are used for flexible and rigid polyurethane foams, floor coverings and adhesives. This wide range of uses means that there are thousands of workers potentially exposed to isocyanates.

In the UK, a management control system is required for workers exposed to isocyanates and for this to be successful workers should not become sensitized. Apart from occupational asthma, airway irritation and asthma-like symptoms such as cough, wheezing and dyspnoea are commonly reported. Other respiratory effects are hypersensitivity pneumonitis, rhinitis and accelerated rate of decline in lung function. Diisocyanates can also cause both irritant and allergic contact dermatitis as well as skin and conjunctival irritation.

Health surveillance that detects occupational asthma is recording failure – there needs to be intervention earlier in the exposure-to-disease paradigm. Although there is evidence that detecting respiratory symptoms early and removing workers from exposure improves prognosis, the goal should be to control exposure to prevent any symptoms.

Please read more on the Society of Occupational Medicine website from September 2007.


This is a long article but a very informative read and is especially relevant for those on post 1995 contracts who were dismissed from the Irish Army Air Corps due to occupational asthma.

Skin Cancer in Irish Air Corps personnel – Basal Cell Carcinoma

Photo of BCC on the leg of a former Air Corps employee who worked daily with Ardrox 666. This person also has cancerous growths on his arm & scalp.

Basal Cell Carcinoma’s are abnormal, uncontrolled growths or lesions that arise in the skin’s basal cells, which line the deepest layer of the epidermis (the outermost layer of the skin). BCCs often look like open sores, red patches, pink growths, shiny bumps, or scars and are usually caused by a combination of cumulative and intense, occasional sun exposure.

Both long-term sun exposure over your lifetime and occasional extended, intense exposure (typically leading to sunburn) combine to cause damage that can lead to BCC. Almost all BCCs occur on parts of the body excessively exposed to the sun — especially the face, ears, neck, scalp, shoulders, and back.

On rare occasions, however, tumors develop on unexposed areas. In a few cases, contact with arsenic, exposure to radiation, open sores that resist healing, chronic inflammatory skin conditions, and complications of burns, scars, infections, vaccinations, or even tattoos are contributing factors.

It is not possible to pinpoint a precise, single cause for a specific tumor, especially one found on a sun-protected area of the body or in an extremely young individual.

Skin cancer (non-melanoma)
Causes grouped by strength of evidence
Strong  Good  Limited 
arsenic aromatic amines acrylamide
benzo(a)pyrene arsenical pesticides vinyl chloride
coal tars benz(a)anthracene
ionizing radiation creosotes
mineral oils dibenz(a,h)anthracene
shale oils dimethyl benzanthracene
UV radiation ethylene oxide
methylcholanthrene
oryzalin
PAHs
pesticides

We are aware of a number of current & former Air Corps technicians who have developed Basal Cell Carcinoma. It is interesting to note that there is good evidence to link creosotes with Basal Cell Carcinoma. Creosotes are a component chemical of Ardrox 666.

However, Basal Cell Carcinoma is a very common cancer and so the occurrence may not be unusual.

Key point as with almost all of the illnesses suffered by Air Corps Chemical Abuse Survivors is of course vigilance. Don’t delay going to your doctor.