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What causes allergic reactions ?

Supplier: Showa
04 July, 2008

There are a multitude of things that can cause allergic reactions where hands are concerned, such as extraneous causes, exposure to chemicals, natural rubber proteins, accelerators and rubber processing chemicals.

Extraneous Causes: Many times contact dermatitis is attributed to gloves when in fact, the causative agent is from another source. The most notable is a change in soap or detergents. One of the most common causes of irritant contact dermatitis is a change in soaps or incomplete rinsing of the hands after washing. Many times switching to a mild pH-neutral cleanser eradicates the problem of irritant contact dermatitis. Skin cleansers designed for and labeled as "heavy-duty cleansers" or "waterless hand cleaners" can have
more irritating ingredients including solvents and abrasives such as silica or wood particles. Many times incomplete rinsing of the cleansers from the skin can cause irritant contact dermatitis. Occlusion of the hand by wearing a glove on top of the residual irritants can aggravate the condition.

Exposure to Chemicals: Thin-gauge disposable gloves are not designed for heavy exposure to chemicals. There are some chemicals that can be safely handled while wearing thin-gauge disposable gloves. However, for heavy exposure to dangerous organic solvents or highly corrosive chemicals, chemical resistant gloves are recommended. Sometimes the fumes of a chemical can permeate a disposable glove and be held next to the skin and cause an irritant contact dermatitis or an allergic sensitization

Glove Reactions: Most allergic reactions to gloves are seen with unsupported gloves. Most of these reactions are reported in the health care settings where gloves are worn most of the time and are changed frequently and hands are washed whenever gloves are changed. There are at least three causes of contact and allergic contact dermatitis (Type IV Delayed Contact Urticaria). Natural rubber proteins, glove powder or rubber accelerators can cause irritant or allergic contact dermatitis. Common rubber accelerators
include: carbamates, thiurams and mercaptobenzothiazole (MBT). These ingredients are present in almost every elastomeric glove made. To determine which ingredient is causing the contact dermatitis, we recommend the following screening protocol:

Allergy Screening:
1. Natural Rubber Proteins:
If you know that you are indeed allergic to natural rubber proteins, change to a synthetic alternative glove such as nitrile or neoprene or PVC gloves. For medical gloves, Best® N-DEX® Non- Latex Gloves are an excellent alternative. None of the synthetic polymer gloves contain natural rubber proteins.
Hypoallergenicity testing using the modified Draize test for chemical sensitivity resulted in no test subjects having any kind of reaction.

2. Glove Powder: Many people believe that they are allergic to glove powder. Most glove powder used to manufacture gloves is food-grade cornstarch used in foods and is not an allergy causing material. However, glove powder has been implicated in cases of latex allergy because it can serve a carrier of the natural rubber latex protein. The latex protein laden cornstarch can be inhaled. So, in latex gloves, a person can react to the latex-containing cornstarch, but in synthetics such as N-DEX nitrile gloves, the cornstarch does not contain latex and will not cause allergic reactions. If a person is still having a rash after changing to Best® N-DEX® Non-Latex Medical Gloves, they could be experiencing irritant contact dermatitis from the corn starch powder. This type of reaction is not
considered an allergic response. If so, we recommend changing to Best® N-DEX® Non-Latex "Powder Free" Medical Gloves. These styles have the suffix PF in the SKU.

3. Rubber Accelerators: If a person is still having an allergic reaction even after changing to the Best® N-DEX® Non-Latex "Powder Free" Medical Glove, they could be allergic to the rubber accelerator MBT. The level of MBT in Best® N-DEX® Non-Latex Medical Gloves is less than half the extractable level determined by Johns Hopkins, Cleveland Clinic and the FDA to trigger an allergic contact dermatitis in MBT-sensitized patients.
This acceleratoris a necessary ingredient and is the only accelerator used in N-DEX gloves. There are no carbamates or thiurams used in N-DEX gloves. These other accelerators are known to cause allergic reactions in more individuals than MBT. Sometimes a patient is allergic to all of the rubber accelerators. In that case, they should be advised to try a vinyl disposable glove or one that is free of accelerators. A viable alternative is to wear a disposable food handler’s polyethylene glove under Best® N-DEX® Non-Latex Medical Gloves. This has worked very well for individuals who are allergic to both Natural Rubber Proteins and to Rubber accelerators.

Allergic Reactions to Gloves:
Most severe allergic reactions to rubber products are caused by one of three things: Natural Rubber Proteins, glove powder or rubber accelerators. The most severe kind of allergic reaction to rubber products occur immediately and can involve the respiratory system. These reactions can be life-threatening and are cause by sensitization to Natural Rubber Proteins. It has been estimated that up to 17% of personnel in the medical profession have had reactions to these proteins. Best® N-DEX® Non-Latex Medical Gloves are made from a 100% non-latex synthetic polymer (nitrile) and contain absolutely NO NATURAL RUBBER PROTEINS. These proteins can be absorbed however, onto the corn starch powder used to make gloves easier to put on and take off. Aerosolized "protein-laden" corn starch has been

Rubber Accelerators:
A small segment of the general population is allergic to rubber accelerators used to process rubber gloves. The accelerators are used in both natural rubber and synthetic rubber (nitrile) gloves. There are several different types of accelerators including: thiurams, carbamates and mercaptobenzothiazole (MBT). Thiuram accelerators are responsible for about 60% of cases of contact dermatitis from accelerators. Carbamates are responsible for about 30% and thiazoles like MBT account for 1 to 5% of the cases.