Towards eco-friendly biocides: preparation, antibiofilm activity of hemibastadin analogues.

The antibiofilm activity of three hemibastadins analogues was evaluated against different marine bacterial strains through mono-species biofilms and through a multi-species model of biofilm. Results showed that compound 3 exhibited interesting antibiofilm efficiencies effective concentrations (EC50 ) in the range of 30-100 µmol l-1 without acute toxicity against bacteria. Toxicity against nontargeted organisms was also considered showing that the compound did not affect the global bacterial community at a concentration of 75-100 µmol l-1 . These results provided baseline data concerning the toxicity of antibiofilm biocides against marine organisms. SIGNIFICANCE AND IMPACT OF THE STUDY: This study reports relevant information about antibiofilm activity of original derivatives of hemibastadin alkaloids. The most active compound was shown to act as a specific anti-biofilm inhibitor without affecting viability of the targeted bacteria no more than those of the global bacterial community of a seawater sample. Taken together, these findings indicate the potentiality of such compounds to be used as original nonbiocidal molecules for designing eco-friendly antifouling solutions.

[Report of the "Health and Environment" commission of the National Academy of pharmacy. Carbon monoxide and environmental health: are carbon monoxide levels in urban areas a health hazard?]. / Le monoxyde de carbone CO et la santé environnementale: CO est-il nocif aux concentrations urbaines actuelles?

In an urban environment, carbon monoxide is produced by incomplete combustion, particularly in motor vehicles. Air pollution caused by CO produced by motor vehicles is controlled by legislation. Legal regulations have considerably lowered emission levels authorized for new vehicles and total CO emission levels. CO levels in the environment (urban environment in general and zones close to motorways) have thus declined. CO remains a public health concern both as a pollutant and as an indicator of air quality. We recall here the more recent approaches used to assess CO-related hazards developed by the Environmental Protection Agency in the United States and pertinent conclusions backing up previously defined reference levels. We then report recent French data concerning CO emission, environmental levels and evaluation procedures for different situations of human exposure: geographical situations, mode of transportation, police force, air sentinels. The third part of this article is devoted to biological data (interaction between CO and hemo-proteins, CO neurotransmitter?) and epidemiological data (serial surveys). The discussion centers on the limitations of epidemiological data and on the difficulty in evaluating hazards solely on the basis of a carboxyhemoglobin threshold. This latter point is particularly important because carboxyhemoglobin is only one of many indicators of air quality. Finally recommendations are proposed concerning weather-related aspects, evaluation of human exposure, and ways of improving biological and epidemiological data.