[Tannin and gallic acid as marker of exposure to hardwood dust]. / I tannini e l'acido gallico come indicatori di esposizione a polveri di legno duro.

The total tannin concentration was determined, using two different SPF methods, in 35 dust powdered wood species, both hard and softwood. Using direct reading-method (280 nm) the concentration varied from 2485 mg/g for Swedish pine to 35,843 mg/g for European oak (quercus robur, hardwood). The data obtained with the second method (Folin-Chocalteau) were well correlated (y = 0.9885x + 4.3373; r = 0.84; n=35) with the data obtained with the first method. The measured concentrations are usually higher in hardwood than softwood tested. Finally, a simple HPLC-DAD method was tested for gallic acid (GA), recently proposed as a marker for oak dust.

[Validation of PM10 and PM2.5 personal samplers: comparison between PEM and CEN-ARPAV selectors]. / Studio di validazione dei selettori per il campionamento personale di PM10 e PM2.5: confronto fra selettori PEM e teste di prelievo CEN-ARPAV.

In order to validate specific personal selectors for the collection of fine particles, 65 double measurements of PM10 and PM2.5 were carried out at the same collection site; thus allowing a comparison between two different methods of sampling. The first method was that normally used by ARPAV in order to sample the above-mentioned granulometric fractions in outdoor environment. The second method was chosen by us for personal sampling (PEM working at 2 l/min and at 4 l/min). In both cases the filters gravimetric analysis conformed to the expectations of D.M. 60 of 2/4/2002. The comparison between the two methods showed a good correlation in both the granulometric fractions: correlation coefficients r for the PM2.5 are equal to 0.96 and 0.99 for the PEM working at 2 l/min and at 4 l/min respectively; r for the PM10 are equal to 0.98 and 0.99 for the PEM working at 2 l/min and at 4 l/min respectively. The analysis of results in terms of fine particles concentration and difference between methods against their mean, shows a slight overestimate of the particles concentration with PEM working at 2 l/min, compared to those working at 4 l/min. Nevertheless, considering the good results obtained even with a flow of 2 l/min, we believe that using PEM working at 2 l/min to monitoring 24 hours-personal exposure assures an improved capacity in the battery-operated pumps.