Using a mathematical model to evaluate the efficacy of TB control measures.

We evaluated the efficacy of recommended tuberculosis (TB) infection control measures by using a deterministic mathematical model for airborne contagion. We examined the percentage of purified protein derivative conversions under various exposure conditions, environmental controlstrategies, and respiratory protective devices. We conclude that environmental control cannot eliminate the risk for TB transmission during high-risk procedures; respiratory protective devices, and particularly high-efficiency particulate air masks, may provide nearly complete protection if used with air filtration or ultraviolet irradiation. Nevertheless, the efficiency of these control measures decreases as the infectivity of the source case increases. Therefore, administrative control measures (e.g., indentifying and isolating patients with infectious TB) are the most effective because they substantially reduce the rate of infection.

Airborne contact dermatitis from 2-amino-2-methyl-1-propanol in a cosmetic company.

The authors described two cases of airborne contact dermatitis caused by 2-amino-2-methyl-1-propanol (AMP 100) in two subjects with periorbital erythema and itching skin. The AMP 100 has been used to replace ammonia as a hair dye component in the cosmetic industry with the purpose to eliminate its smell. Patch tests proved positive only to dilutions of 10% and 20% in the two described patients, as well as in other six asymptomatic subjects operating in the same working environment. The authors have diagnosed an irritative airborne contact dermatitis by AMP 100.

[Sensitization and allergic pathology in a group of workers employed in insect breeding for biological pest control]. / Sensibilizzazioni e patologia allergica in un gruppo di lavoratori addetti all'allevamento di insetti utili per la lotta biologica.

On the basis of the results of a previous study and immuno-allergological tests, a group of workers employed in breeding insects for biological pest control were studied to ascertain whether any new sensitizations to arthropods recently included in the work cycle occurred and whether any new allergic diseases were observed. The results confirmed a high sensitization to Ephestia kuehniella and to Orius, the latter probably due to contamination; sensitization to Tetranicus urticae and to Planococcus citri were observed, although to a lesser degree. It is concluded that the insects used in biological pest control are highly allergogenic and that the protective devices used up to the present were ineffective; the authors therefore recommend the use of closed or semi-closed cycles along with local ventilation equipment.

gamma-Glutamyltransferase isoenzyme pattern in workers exposed to tetrachloroethylene.

In compliance with the mandatory medical surveillance of workers exposed to tetrachloroethylene (PCE) in Italy, isoenzyme fractioning of serum gamma-glutamyltransferase (GGT) was performed on 141 workers of both sexes and on 130 control subjects. None of the workers showed any clinical symptoms of liver disease and their enzymatic profiles, including AST, ALT, 5'-NU, ALP, and GGT, were within the normal reference limits. A statistically significant increase in total GGT serum level was found in the exposed subjects, which was associated with an increase in one of the two fractions normally present in healthy individuals (GGT-2), as well as with the appearance and progressive increase of the level of a fraction (GGT-4) considered to be an expression of hepato-biliary impairment. Further research is ongoing among these workers, which will clarify whether or not electrophoretic GGT tests may be useful in detecting liver function changes due to occupational exposure to PCE.