Posted By andyp
TK,

Sensitisation & allergic reaction are two separate entities. Sensitisation is where the substance / material etc causes an inability for the individual to effectively fight infections, diseases etc.

For example, solder fluxes can cause sensitisation in individuals with prolonged or uncontrolled use; the sensitisation often results in the individual contracting occupational asthma despite the individual not suffering from it previously.

In brief, sensitisation may often result in long term health effects i.e. occupational asthma, eczema, dermatitis etc. Whereas an allergic reaction often causes an immediate & short term health problem i.e. rash, shortness of breath etc.

Posted By Mark Drury
Yes I think they are.

I have an allergy to wasp stings and my medical notes state.

"Sensitisation causing acute allergic reaction"

The first is a condition, allergic reation is an effect following exposure.

Mark

Posted By Phil Grace
TK, Not entirely sure I agree with the comments that the two conditions are the same.

Allergies/allergic reactions are an abnormal response of the body's immune system to some form of stimulus. Thus people display an allergic reaction from exposure to cat fur/saliva. The body recognises a foreign protein and seeks to overcome it.

Sensitisation is a result of exceptional or repeated exposure to a stimulus that generates antibodies in the boy. And then when the body experiences an exposure in the future the allergic reaction or response is triggered. The problem is that the future exposures can be at very low levels, below those that would be regarded as causing occupational problems. Thus a person who works with isocyanates could become sensitised through repeated low level exposures AND then having stopped working at the factory display an allergic reaction following some low level, incidental exposure in another workplace, at home etc.
It should be noted that there are reported cases of sensitisation occurring after single high exposures e.g. if there were a large volume escape in the workplace.

Once upon a time there were problems with workers in some industries who became sensitised to nickel who would then display an allergic reaction from handling cupro-nickel coins or wearing a watch with a nickel plated buckle. Similarly healthcare workers who use latex gloves can ,over time become sensitised such that even the slightest exposure to latex can trigger an allergic/asthmatic reaction. (Dugmore case)

Hope this helps:
Phil
A tip which you may know: In Google type define: sensitisation (or whatever it is you want to know about)

Posted By Paul Leadbetter
Thomas

Absorption of anything which accumulates in the body could eventually give rise to adverse effects as the body burden increases. Lead springs to mind although it is not a COSHH issue.

Paul

Posted By Chris Packham
1. Sensitisation is the development in the body of antibodies or t-lymphocytes that are specific to a particular molecule. This is the first step in developing an allergic reaction. However, it is perfectly possible to be sensitised but not allergic.
2. Allergy is when as a result of sensitisation on subsequent exposure to the molecule and when this has penetrated the body to reach the relevant cells (mast cell or langerhans cell depending upon the type of immune reaction) this then overreacts to release excessive quantities of inflammatory mediators, e.g. histamine.
3. It is possible to be exposed repeatedly, possibly for many years, to a sensitiser with no sensitisation or allergic reaction. This can occur at any time with no prior warning. These is no prior indication nor any immediate sign of sensitisation. It is only on the subsequent exposure that an allergic reaction may occur.
4. Once sensitisation has occurred, any subsequent exposure may lower the threshold at which an allergic reaction occurs, thus increasing the probability of an allergic reaction.
5. In response to your other query, with irritant contact dermatitis it is almost always chronic and multifactorial, i.e. due to repeated exposures to many different irritants over a period of time, possibly years. This makes identifying the actual cause of an irritant contact dermatitis often very difficult.

Chris

Posted By TK
Thanks for all the responses. As usual excellent advice.

Thomas