Khat (Catha edulis) chewing is widespread in the region of East Africa. Even low levels of organochlorine pesticides (OCPs) in khat could induce public health concern. In a market-based study, from five popular khat varieties, a total of 35 composite khat samples were analyzed for dichlorodiphenyltrichloroethane (DDT) and its main transformation products, and four hexachlorocyclohexane (HCH) isomers. Extraction was carried out by quick, easy, cheap, effective, rugged and safe method (QuEChERS). OCP concentrations were determined by head space solid phase microextraction coupled to gas chromatography-mass spectrometry (HS-SPME–GC–MS). Every sample contained β-HCH above the maximum residue limit set by the European Commission. For total DDT, this was the case for 25.7% of the samples. The ratios of (p,p′-DDD + p,p′-DDE) to p,p′-DDT were less than one for 85% of khat samples, demonstrating recent use of DDT in khat farmlands. Conversely, the ratio of β-HCH to total HCH varied from 0.56 to 0.96, implying historical input of technical HCH. Assuming a daily chewable portion of 100 g, dietary intakes of p,p′-DDT, total DDT and total HCH by adults ranged from 3.12 to 57.9, 6.49 to 80.2 and 39.2 to 51.9 ng (kg body weight)−1 day−1, respectively. These levels are below acceptable levels suggested by international organizations. Chewing khat showed lower non-cancer health risk, but showed relatively higher cancer risk in terms of OCPs. Because khat is chewed without being subjected to any treatment, uncertainties associated with estimated intakes and health risks should be low. Therefore, this practice is of great concern.

Purpose Organochlorine pesticides (OCPs) like lindane and DDT have been used extensively after World War II until the 1990s. Still, residues of these pesticides can be found in agricultural soils all over the world, especially in developing countries. Often, they occur in extensive areas and elevated concentrations so that food safety is jeopardized. Hence, simple, cheap, and fast analytical methods are needed for a straight-forward assessment of risks. A miniaturized solid–liquid extraction combined with solid-phase microextraction (SPME) based on a proven ISO method is presented. Methods The performance of the method is evaluated by extracting three different soils which were spiked with HCH and DDT congeners, and trifluralin, and aged for 35 days. The results are compared with those of a modified quick, easy, cheap, efficient, rugged, and safe (QuEChERS) method. For further validation, both methods are applied to three environmental soil samples. Results Validation results show limits of detection and quantification as well as recovery rates in good agreement with standard requirements. The new method was found to be quicker than QuEChERS, which requires time-consuming preparation of reagents. Conclusion Merits include low time and sample volume requirements (0.5 g) and the possibility to extract many samples simultaneously, which allows the screening of large sample sizes to determine the pollution status of whole landscape regions. However, access to an automated SPME apparatus is assumed. The authors can recommend this method as a cheap and fast alternative where SPME is available.

The suitability of lake sediment cores to reconstruct past inputs, regional pollution, and usage patterns of pesticides has been shown previously. Until now, no such data exist for lakes in eastern Germany. Therefore, 10 sediment cores (length 1 m) of 10 lakes in eastern Germany, the territory of the former German Democratic Republic (GDR), were collected and cut into 5–10-mm layers. In each layer, concentrations of trace elements (TEs) As, Cd, Cr, Cu, Ni, Pb, S, and Zn, as well as of organochlorine pesticides (OCPs), i.e., dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH), were analyzed. A miniaturized solid–liquid extraction technique in conjunction with headspace solid-phase microextraction (HS-SPME) and gas chromatography–mass spectrometry (GC–MS) was used for the latter. The progression of TE concentrations over time is uniform. It follows a trans-regional pattern and is indicative of activity and policy making in West Germany before 1990 instead of those in the GDR. Of OCPs, only transformation products of DDT were found. Congener ratios indicate a mainly aerial input. In the lakes’ profiles, several regional features and responses to national policies and measures are visible. Dichlorodiphenyldichloroethane (DDD) concentrations reflect the history of DDT use in the GDR. Lake sediments proved to be suitable to archive short- and long-range impacts of anthropogenic activity. Our data can be used to complement and validate other forms of environmental pollution long-term monitoring and to check for the efficiency of pollution countermeasures in the past.

The suitability of lake sediment cores to reconstruct past inputs, regional pollution, and usage patterns of pesticides has been shown previously. Until now, no such data exist for lakes in eastern Germany. Therefore, ten sediment cores (length 1 m) of ten lakes in eastern Germany, the territory of the former German Democratic Republic (GDR), were collected and cut into 5-10 mm layers. In each layer, concentrations of trace elements (TEs) As, Cd, Cr, Cu, Ni, Pb, S, Zn, as well as of organochlorine pesticides (OCPs) were analyzed. A miniaturized solid-liquid extraction technique in conjunction with headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) was used for the latter. Of OCPs, only transformation products of dichlorodiphenyltrichloroethane (DDT) were found. Congener ratios indicate a mainly aerial input. In the lakes’ profiles, several regional features and also responses to national policies and measures are visible. Dichlorodiphenyldichloroethane (DDD) concentrations reflect the history of DDT use in the GDR. TEs show a uniform progression over time. They follow a trans-regional pattern and are indicative of activity and policy making in West Germany before 1990 instead of those in the GDR. Lake sediments proved to be suitable to archive short- and long-range impacts of anthropogenic activity. Our data can be used to complement and validate other forms of environmental pollution long-term monitoring and check for the efficiency of pollution counter measures in the past.

This study presents a survey on pesticide use, pesticide storage and pesticide disposal among 100 residents near a former pesticide store in rural Georgia using a standardized paper questionnaire. More than one quarter of the participants responded that the age of the pesticides they use is higher than 20 years. Based on this finding, it cannot be excluded that persistent organic pollutants like Dichloro-diphenyl-trichloroethane and hexachlorocyclohexanes still are released to the environment. Knowledge about active ingredients of pesticides is lacking among farmers: More than two thirds state that they know the active ingredients, while less than 10% mention an active ingredient matching the brand name they report. Purchasing pesticides in containers without labels appears to be common practice. Information about the pesticides is mainly obtained from the pesticide retailer, while the label is less important as a source of information. More than 95% of the participants store the pesticides in a separate store, but appropriate possibilities of hazardous waste disposal seem to be insufficient in rural areas in the region. The finding that pesticides are purchased and stored in repacked secondary containers, poses direct risks and hampers communication of risks to users. Improving (implementation of) regulations for pesticide handling and strengthening local knowledge through better vocational training can improve soil and groundwater protection and sustainable use of resources. Article highlights One of the main findings is that residents report using the pesticides for a long time. Not only are the pesticides used way longer than they may remain suitable for use, but also the pesticides could be dating from before international legislation entered into force which was set up to protect from long-lived organic pollutants (the Stockholm Convention). Our results show that often pesticides are repacked and stored in alternative containers such as plastic containers for detergents. This means users cannot find important information on how to use pesticides safely on these alternative containers. The label cannot be used as a source of information for example regarding health risks. This may lead to poisoning of users. In Georgia, the transition process results in poor implementation of environmental regulations such as laws about waste management. The results show that educational level has a positive influence on choosing safe storage options such as a separate store. The results indicate that especially in rural areas possibilities of proper disposal of old pesticides or other dangerous chemicals are poor. This has implications for the health of residents. Efforts to better implement environmental regulations should be strengthened especially in rural areas to overcome the legacy of long-lived pesticides which are now banned. Old pesticides might still be in use because they are difficult to dispose of safely.

The suitability of lake sediment cores to reconstruct past inputs, regional pollution, and usage patterns of pesticides has been shown previously. Until now, no such data exist for lakes in eastern Germany. Therefore, ten sediment cores (length 1 m) of ten lakes in eastern Germany, the territory of the former German Democratic Republic (GDR), were collected and cut into 5-10 mm layers. In each layer, concentrations of trace elements (TEs) As, Cd, Cr, Cu, Ni, Pb, S, Zn, as well as of organochlorine pesticides (OCPs) were analyzed. A miniaturized solid-liquid extraction technique in conjunction with headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) was used for the latter. Of OCPs, only transformation products of dichlorodiphenyltrichloroethane (DDT) were found. Congener ratios indicate a mainly aerial input. In the lakes’ profiles, several regional features and also responses to national policies and measures are visible. Dichlorodiphenyldichloroethane (DDD) concentrations reflect the history of DDT use in the GDR. TEs show a uniform progression over time. They follow a trans-regional pattern and are indicative of activity and policy making in West Germany before 1990 instead of those in the GDR. Lake sediments proved to be suitable to archive short- and long-range impacts of anthropogenic activity. Our data can be used to complement and validate other forms of environmental pollution long-term monitoring and check for the efficiency of pollution counter measures in the past.

The suitability of lake sediment cores to reconstruct past inputs, regional pollution, and usage patterns of pesticides has been shown previously. Until now, no such data exist for lakes in eastern Germany. Therefore, ten sediment cores (length 1 m) of ten lakes in eastern Germany, the territory of the former German Democratic Republic (GDR), were collected and cut into 5-10 mm layers. In each layer, concentrations of trace elements (TEs) As, Cd, Cr, Cu, Ni, Pb, S, Zn, as well as of organochlorine pesticides (OCPs) were analyzed. A miniaturized solid-liquid extraction technique in conjunction with headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) was used for the latter. Of OCPs, only transformation products of dichlorodiphenyltrichloroethane (DDT) were found. Congener ratios indicate a mainly aerial input. In the lakes’ profiles, several regional features and also responses to national policies and measures are visible. Dichlorodiphenyldichloroethane (DDD) concentrations reflect the history of DDT use in the GDR. TEs show a uniform progression over time. They follow a trans-regional pattern and are indicative of activity and policy making in West Germany before 1990 instead of those in the GDR. Lake sediments proved to be suitable to archive short- and long-range impacts of anthropogenic activity. Our data can be used to complement and validate other forms of environmental pollution long-term monitoring and check for the efficiency of pollution counter measures in the past.