Are luminescent bacteria suitable for online detection and monitoring of toxic compounds in drinking water and its sources?

Biosensors based on luminescent bacteria may be valuable tools to monitor the chemical quality and safety of surface and drinking water. In this review, an overview is presented of the recombinant strains available that harbour the bacterial luciferase genes luxCDABE, and which may be used in an online biosensor for water quality monitoring. Many bacterial strains have been described for the detection of a broad range of toxicity parameters, including DNA damage, protein damage, membrane damage, oxidative stress, organic pollutants, and heavy metals. Most lux strains have sensitivities with detection limits ranging from milligrams per litre to micrograms per litre, usually with higher sensitivities in compound-specific strains. Although the sensitivity of lux strains can be enhanced by various molecular manipulations, most reported detection thresholds are still too high to detect levels of individual contaminants as they occur nowadays in European drinking waters. However, lux strains sensing specific toxic effects have the advantage of being able to respond to mixtures of contaminants inducing the same effect, and thus could be used as a sensor for the sum effect, including the effect of compounds that are as yet not identified by chemical analysis. An evaluation of the suitability of lux strains for monitoring surface and drinking water is therefore provided

Pesticide content in drinking water samples collected from orchard areas in Central Poland

Samples of drinking water collected in Warka-Grójec region of central Poland were tested for the presence of pesticides. Data obtained from analysis of water samples will be used for future epidemiological and environmental studies in the region. Samples were collected during spring and autumn of 2002-2003 from dug wells, deep wells and water mains in 81 randomly-selected rural households scattered throughout this region of extensive agriculture. The concentration of pesticides from four main chemical groups was determined by gas chromatography: organochlorines (lindane, DDT, methoxychlor), triazines (atrazine, simazine), organophosphates (acephate, diazinon, fenitrothion) and pyrethroids (alpha-cypermethrin, deltamethrin). Two-year monitoring of drinking water samples indicated the presence of DDT and methoxychlor contamination. Pyrethroids were generally not detected, with the exception of alpha-cypermethrin found in only a few samples. Triazines were also found in water samples collected in the course of the study with higher incidence during spring period. Organophosphates were by far the most common contaminants of drinking water in this region. Almost all samples were contaminated by signifi cant amounts of fenitrothion. The present study reveals an urgent need for systematic monitoring of drinking water quality in regions of intensive agriculture, since they are highly vulnerable to pesticide contamination. Consumption of pesticide-contaminated water may have a negative impact on the population living in this area, which also requires scientifi c assessment