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The innovation of this study was to assess which types of AC derived from three selected date stones (Species: Phoenix dactylifera; types: Ajwa, Anbari, Khudri) showed better performance for the adsorption of organochlorine pesticides from contaminated water (outflow water from WWTP and agricultural effluent). In the bed column, the first experiments demonstrated that AC prepared from Ajwa date stones has a high efficiency to eliminate OCPs from an aqueous solution that 10 g of adsorbent was treated with 12 L of contaminated water. Therefore, the effects of the adsorbent mass of the material prepared from Ajwa date stones and flow rate of organochlorine pesticides onto prepared activated carbon were studied; the optimum adsorption capacity for all studied organochlorine pesticides from the water having a natural pH has reached 70–100%, using a 50 g of adsorbent in the particle size range of 0.75–100 mm, a flow rate of 2.5 mL/min, and an inlet concentration 57 µg/L. Finally, this AC proved its effectiveness to control water pollution by OCPs for agricultural and WWTPs effluents.

International audience; Phthalic Acid Esters (PAEs) are a group of emerging organic contaminants that have become a serious issue because of their ubiquitous presence and hazardous impact on the marine environment worldwide. Seawater samples were collected monthly from December 2013 to November 2014 in the northwestern Mediterranean Sea (Marseille Bay). The samples were analyzed for dissolved organic carbon (DOC) as well as the molecular distribution of dissolved PAEs by using solid phase extraction followed by gas chromatography and mass spectrom-etry (GC/MS) analyses. The results demonstrated the occurrence of six PAEs, including dimethyl phthalate (DMP), diethyl phthalate (DEP), di-isobutyl phthalate (DiBP), din -butyl phthalate (DnBP), benzylbutyl phthalate (BzBP) and diethylhexyl phthalate (DEHP), with total concentrations ranging from 130 to 1330 ng L −1 (av. 522 ng L −1). In Marseille Bay, the highest concentrations were detected in the bottom water from June to November 2014 and in the whole water column during the winter mixing period. This result suggests that resuspension of PAE-rich sediment, in relation to the accumulation of plastic debris above the seabed, or the higher degradation rate in the upper layer of the water column, plays a significant role in the PAE dynamics in coastal water. DEHP was the most abundant PAE in all of the surface samples and the summer bottom samples, followed by DiBP and DnBP, which also represent the largest fractions in the other bottom samples.

Soil contamination by heavy metals (HM) and persistent organic pollutant such as organochlorine pesticides (OCPs) is a worldwide global concern. These pollutants are introduced to the soil through human activities, including mining, smelting, industry, and agriculture. They alter soil properties and affect all living beings. The present work is focused on the contamination level of OCPs and HMs in soils, originated from six villages located in an agricultural area northern Lebanon-Akkar. Determination of OCPs was established by accelerated solvent extraction followed by GC–MS analysis, and investigation of heavy metals was performed by total extraction occupied with ICP-AES. OCPs were found at high levels. Concentrations of DDTs, HCHs and cyclodiene insecticides were as following 29.4, 10.1 and 37.3 ng/g. A high concentration of OCPs was found in the cultivated area and a huge difference was observed between the same region and tillage land. Furthermore, a variation of concentration was determined also among depth and soil category. The predominance of DDE has been presented and a historical application of dicofol has been identified by 2,4′DDT/4,4′DDT and DDE + DDD/DDTs values. An unbroken and recent use of HCHs, chlordane, and heptachlor has been manifested based on the values of α-HCH/γ-HCH, Cis/trans-chlordane and heptachlor/heptachlor epoxide ratios, respectively. Nickel was mostly metal-detected at all sites; and a moderate pollution by cd (Enrichment factor > 25) has been provided probably due to the use of pesticides comprising a certain trace of this metal during agricultural practices. As a conclusion, the soil of Akkar is not only contaminated by pesticides but also with heavy metals which necessitates an effort to protect people living around this region from their risk.

According to its high production and value, Akkar is considered as the second agricultural region in Lebanon. Groundwater constitutes the principal source of water in Akkar including drinking water of local inhabitants in Akkar. As such, the contamination of groundwater by organic pollutants can impact directly the population health. In this study, we evaluated the contamination status of groundwater in this region. Three classes of pesticides including 19 organochlorine (OC) pesticides, 8 organophosphorus (OP) pesticides, and 6 organonitrogen (ON) pesticides were monitored in 15 groundwater samples collected from different villages on the Akkar plain. Samples were extracted by using solid phase extraction (SPE) and analyzed by gas chromatography coupled with mass spectrometry (GC-MS). The results showed high contamination of Akkar groundwater by OCs with levels that can reach 58.9 μg/L. They were detected in the majority of the sample and represent 95–100% of ∑pesticides. Our results showed the recent use of these molecules with an average level of 0.3 and 0.39 μg/L for ∑HCHs and DDTs, respectively. Their concentrations were higher than those observed in the same region in 2014 and other regions elsewhere. OPs were also detected at high levels and among them, methylparathion was the predominant OP detected (44.6 μg/L). For ONs, lower levels were measured in all samples with a mean value of 5.6 μg/L. As a conclusion of this work, groundwater on the plain of Akkar was remarkably contaminated by the studied pesticides; indefinitely, more efforts should be taken to manage the pesticide use in this region, assess, and reduce their effects on human health. In the future, the application of organic farming can be a great solution to the groundwater contamination problem.

Surface waters, especially natural rivers always act as receiving waters for various kinds of organic contaminants from municipal and industrial wastewaters, agricultural activities, organic chemicals in use, non-point source pollutions. Due to their toxicity, persistency and wide diffusion, polychlorinated biphenyls (PCBs), pesticides, phthalates, polycyclic aromatic hydrocarbons (PAH) and their alkylated homologues (Me-PAHs) are among the organic contaminants the most often monitored in the environment. Determination of the contamination level is the crucial first step of environmental research. Field investigations have clearly demonstrated their importance on various studies on the contamination levels, the origin, and impact of contaminants in the aquatic ecosystems. The present paper is an effort on the field studies focusing on persistent organic pollutants: PCBs, PAHs and Me-PAHs, phthalates and pesticides in Somme River water located on Northern France. The sampling zone is characterized by fields of agriculture surrounding urbanized and industrialized areas and constitutes a place embedded with strong fishing activities. However, the river section of interest is also known for the high levels of PCB in sediments. The water were analyzed for 28 PCBs, 16 PAHs and 18 Me-PAHs, 6 phthalates and 28 pesticides with the aim to determine the dispersion trend and the water quality of the sampled water.

A new method for the analysis of pesticides in agricultural soils by using liquid chromatography coupled with a high-resolution quadrupole time-of-flight mass spectrometer (LC-QTOF-MS) has been developed. Twenty-four pesticides including herbicides, insecticides or fungicides have been studied. The linearity of the external calibration of the pesticides obtained from levels of concentration ranging from 0.010 to 400 µg/Lgives satisfactory results with the correlation coefficients higher than 0.99. The quantification limits of the equipment range from 0.010 to 1.250 µg/L and correspond to the lowest standard in the calibration range for which the residual deviation is less than 60%. An experimental design has been used to optimise the parameters of pressurised-liquid extraction (PLE) of pesticides in soils. The optimised conditions have been found by using methanol as extraction solvent at a temperature of 80°C, a pressure of 150 Bars and 2 extraction cycles of 5 minutes. The mean recoveries of pesticides (Mean) are higher than 72% with a relative standard deviation(RSD) less than 21%. These results demonstrate the good efficiency of PLE for the extraction of pesticides in agricultural soils of different nature. The LC-QTOF-MS is a sensitive, linear and robust instrument for the quantification of pesticides in unpurified soil extracts by external calibration. This analytical tool is not subjected to matrix effects of soil extracts.

A new method for the analysis of pesticides in agricultural soils by using liquid chromatography coupled with a high-resolution quadrupole time-of-flight mass spectrometer (LC-QTOF-MS) has been developed. Twenty-four pesticides including herbicides, insecticides or fungicides have been studied. The linearity of the external calibration of the pesticides obtained from levels of concentration ranging from 0.010 to 400 µg/Lgives satisfactory results with the correlation coefficients higher than 0.99. The quantification limits of the equipment range from 0.010 to 1.250 µg/L and correspond to the lowest standard in the calibration range for which the residual deviation is less than 60%. An experimental design has been used to optimise the parameters of pressurised-liquid extraction (PLE) of pesticides in soils. The optimised conditions have been found by using methanol as extraction solvent at a temperature of 80°C, a pressure of 150 Bars and 2 extraction cycles of 5 minutes. The mean recoveries of pesticides (Mean) are higher than 72% with a relative standard deviation(RSD) less than 21%. These results demonstrate the good efficiency of PLE for the extraction of pesticides in agricultural soils of different nature. The LC-QTOF-MS is a sensitive, linear and robust instrument for the quantification of pesticides in unpurified soil extracts by external calibration. This analytical tool is not subjected to matrix effects of soil extracts.

International audience