Influence of exposure sites on trace element enrichment in moss-bags and characterization of particles deposited on the biomonitor surface.

The hypothesis that exposure environment and land use influence element accumulation and particulate size composition in transplants of Hypnum cupressiforme has been tested using moss-bags containing oven-devitalized material. The samples were exposed for three months in ten green sites and ten roadsides in two areas with different land use (A, residential; B, residential/industrial) in the Trieste conurbation (NE Italy). Observations by SEM and EDX-ray microanalysis revealed that particle density was smaller in samples exposed in A than in B, with prevalence of particles containing Al, Ca, Fe and Si, and in good accordance with the element contents measured by acid digestion and ICP-MS. Moss-bags were generally less contaminated in green sites than in roadsides, apparently due to the different enrichment in coarse particles. In both environments, however, the majority of entrapped particles (up to 98.2%) belongs in the inhalable, small size classes (≤PM(10)). The need for careful selection of the exposure sites during the phase of biomonitoring planning is discussed.

Lichen and moss bags as monitoring devices in urban areas. Part I: influence of exposure on sample vitality.

Samples of the lichen Pseudevernia furfuracea (L.) Zopf and the moss Hypnum cupressiforme Hedw. were exposed for 6 weeks in nylon bags in two air pollution monitoring stations in Trieste and Naples (Italy) with different climates and pollution loads to evaluate influence of environmental conditions on sample vitality. This was assessed before and after exposure by transmission electron microscopy observations, K cellular location, and measurements of C, N, S and photosynthetic pigments content, CO2 gas exchange, and chlorophyll fluorescence. Almost all data sets indicate that exposures caused some damage to the species, considerably heavier in the moss, especially in Naples. The two cryptogams differed significantly in accumulation and retention of C, N, and S, the lichen clearly reflecting NO2 availability. The difference in vitality loss was related to the different ecophysiology of the species, because concentrations of phytotoxic pollutants were low during exposure. Critical notes on the analytical techniques are also given.

Lichen and moss bags as monitoring devices in urban areas. Part II: trace element content in living and dead biomonitors and comparison with synthetic materials.

Lobes of the lichen Pseudevernia furfuracea (L.) Zopf and shoots of the moss Hypnum cupressiforme Hedw. were subjected to different treatments (water washing, oven drying, HNO3 washing, NH4-oxalate extraction) to assess the influence of vitality on accumulation efficiency, during a 6-week exposure in bags in two Italian cities, Trieste and Naples. No trend emerged between treatments, in terms of accumulation ability, for major and trace elements. Only water-washed lichens showed an increased C and N content after exposure in both cities. Element concentrations generally reached higher values in mosses than in lichens, especially for Al, Fe, and Zn (both cities), and for Cu, Mg and Na (Naples). Surface development strongly influenced accumulation capacity of the biomonitors. Quartzose and cation exchange filters revealed, on a weight basis, a poor performance. In urban environments, surface interception of atmospheric particulate seems to play a major role in accumulation, irrespective of organism vitality.

Effect of viloxazine on serum carbamazepine levels in epileptic patients.

The present study describes the interaction between carbamazepine (CBZ) and viloxazine, a recently synthesized antidepressant agent. Seven epileptic patients on chronic anticonvulsant therapy showed a significant (p less than 0.005) increase in steady-state serum CBZ levels (from 8.1 +/- 2.5 SD to 12.1 +/- 2.5 SD micrograms/ml) when viloxazine (300 mg/day) was added to the therapy. The effect was associated with the appearance of mild CBZ intoxication. The symptoms of this intoxication (i.e., dizziness, ataxia, fatigue, drowsiness) disappeared rapidly, and serum CBZ levels decreased to the basal values, when viloxazine administration was stopped.

A sensitive gas chromatographic assay for the determination of serum viloxazine concentration using a nitrogen-phosphorus-selective detector.

A gas-liquid chromatographic procedure for measuring the serum levels of the antidepressant viloxazine is described. The drug and the internal standard [imipramine (IMI)] are extracted from 1 ml serum. The method involves a three-step extraction, derivatization of viloxazine with acetic anhydride, and injection into a gas chromatograph equipped with a nitrogen-phosphorus-selective detector. The retention times for IMI and viloxazine were 4.7 and 6.1 min, respectively. The standard curves were linear over the 100- to 2,000-ng/ml range. The recovery averaged 64.5% and the lowest detection limit was 80 ng/ml. The within-run and day-to-day coefficients of variations were 11.9 and 12.5%, respectively, at 250 ng/ml, and 8.9 and 9.2%, respectively, at 1,500 ng/ml. The method is adequate both for single-dose pharmacokinetic studies and for monitoring serum viloxazine levels in chronically treated patients.