The aquatic environment is the ultimate receptacle of environmental pollution. Many micro-pollutants are present and show toxic effects to aquatic systems (bioaccumulation in tissues, inhibition of growth, endocrine ...
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The aquatic environment is the ultimate receptacle of environmental pollution. Many micro-pollutants are present and show toxic effects to aquatic systems (bioaccumulation in tissues, inhibition of growth, endocrine dysfunction, etc.). The Water Framework Directive (WFD) aims to restore the good ecological and chemical quality of aquatic environments by 2015. For this, it imposes low Environmental quality standards (EQS) and increased monitoring of water bodies. Beyond regulated micro-pollutants, some "emerging" have been detected at low concentrations (ng L-1) in aquatic systems. Under this term are grouped pharmaceutical compounds, some pesticides, hormones, etc. All of these micro-pollutants are introduced into the environment through several sources: atmospheric deposition, soil leaching and industrial or domestic discharges.This work is specifically focused on alkylphenols, present on the list of priority hazardous compounds in the WFD, their ethoxylated derivatives, bisphenol A and pharmaceutical compounds. As a first step, particular attention was paid to the analysis of these compounds. Analytical methods of liquid chromatography coupled to mass spectrometry (LC / MS) and tandem mass spectrometry (LC-MS/MS) for alkylphenols were optimized by improving quality controls and paying attention to the extraction of sensitive compounds toward contamination (manipulator, atmosphere, etc.). To overcome the problems associated with sample contamination by these compounds during the extraction, solid phase microextraction (SPME) and a method of analysis by gas chromatography coupled to mass spectrometry (GC-MS) was developed. In a second step, the fate and behavior of alkylphenols, their ethoxylated derivatives and pharmaceutical compounds in sewage treatment plants (WWTPs), sources of introduction into aquatic systems proved, were studied. This study has allowed showing the decrease of concentrations during treatment in WWTPs for all compounds studied except for alkylphenoxy acetic acid (NP1EC) which is formed during secondary treatment, carbamazepine, and to a lesser extent diclofenac remain stable. Only tertiary treatments allow significant removal of these compounds. The presence of more than 50% of alkylphenols and ethoxylated derivatives in the particulate phase lead to significant adsorption of these compounds into sludges. In order to improve environmental monitoring, during experiments conducted in the laboratory POCISTM standard (Polar Organic Chemical Integrative Samplers), "pharmaceuticals" configuration, have been developed for sampling alkylphenols, their ethoxylated derivates, bisphenol A and pharmaceutical compounds. Alkylphenols and their ethoxylated derivatives are accumulated with a lag phase in standard POCISTM showing the influence of the membrane on the mass transfer of these compounds. The standard POCISTM were optimized by changing the nature of the membranes for sampling alkylphenols and their ethoxylated derivatives. These new tools are named POCISTM-like. The POCISTM-Nylon 0.1 µm and 30 µm are POCISTM-like showing a strong power concentrator for alkylphénols, their ethoxylated derivatives and BPA while eliminating the lag phase observed in standard POCISTM. These POCISTM-like were subsequently validated in mesocosms and in the environment in order to highlight their integrative nature, allowing to overcome the matrix effect and to detect some compounds at concentrations below the limits of quantification.
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