Monitoring on chemical and biological pollutants in sea waters of central-northern Sardinia.

INTRODUCTION: The aims of this study are to assess the quality of the coastal waters of central-northern Sardinia through data from a monitoring network and to outline maps and experimental models of environmental risk correlated to the presence of chemical and microbiological contaminants. The area studied is the coast between Capo Falcone and the mouth of the river Coghinas, in the northwestern part of the island. METHODS: In a first phase, 7 sampling stations of sea water and 1 sampling station of bivalve molluscs (Mytilus galloprovincialis Lam.) were identified. For each transept 3 different collection points at respectively 500, 1000, and 3000 meters from the coast for a total 21 sampling sites were identified. In a second phase, another 7 transepts were identified, 2 of which on the island of Asinara. RESULTS: As regards the microbiological monitoring of the sea water, very low concentrations of Total coliforms, Faecal coliforms and Faecal Streptococci were found and no Salmonella were isolated. Chemical analysis of the waters showed a high constant presence of phenols. In the bivalves we found rather high concentrations of Faecal coliforms without any clear seasonal variation, while no Salmonella was isolated in any of the examined samples. DISCUSSION: The results show that the considered area is not affected by serious pollution processes, thus allowing to express a completely satisfactory judgement on its state of health. However anthropic pressure in the considered territory is testified by the presence in the water of high concentrations of phenols. CONCLUSIONS: The results point out to the necessity of targeted and rational preventive action by means of control and protection measures for environmental ecosytems.

Periodontal status in an Italian young adult population. Prevalence and relationship with periodontopathic bacteria.

To determine the prevalence of periodontitis in an Italian young adult population and the relationship with Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia in subgingival plaque. A full-mouth periodontal and oral examination was performed in 70 subjects. Dental and behaviour habits were assessed with a standardised questionnaire. Subgingival plaque samples were collected from the deepest pocket of the first molars in each quadrant with a sterile curette. A. actinomycetemcomitans, P. gingivalis and P. intermedia were detected using a multiplex polymerase chain reaction. At subject level, the prevalence of bleeding on probing, calculus, normal pocket depth (PD), PD > 5mm and bacterial positivity were 44.8%, 43.3%, 22.9%, 11.4% and 95.7%, respectively. At quadrant level bacterial prevalence was 79.4%; P. intermedia was the most common bacteria (79.0%); A. actinomycetemcomitans had a prevalence of 40.8%. A significant linear trend across categories of gingival conditions (healthy, bleeding on probing, calculus presence) was detected for P. intermedia (p = 0.0038) and A. actinomycetemcomitans (p = 0.00005) proportions. No significant association was observed between pathogenic bacteria and PD, nor with behavioural attitudes. Gingival conditions are found to be a good predictors (VPP = 85%) for periodontopathic bacteria. For the Italian population, as no data are present, prospective longitudinal studies are needed to examine the relationship between PD and bacteria presence with periodontal disease onset and/or progression.