Systemic fungicide use has increased over the last decades, despite the susceptibility of resistance development and the side effects to human health and the environment. Although herbicides and insecticides are detected more frequently in environmental samples, there are many fungicides that have the ability to enter water bodies due to their physicochemical properties and their increasing use. Key factors affecting fungicide fate in the environment have been discussed, including the non-target effects of fungicides. For instance, fungicides are associated with the steep decline in bumblebee populations. Secondary actions of certain fungicides on plants have also been reported recently. In addition, the use of alternative eco-friendly disease management approaches has been described. Constructed Wetlands (CWs) comprise an environmentally friendly, low cost, and efficient fungicide remediation technique. Fungicide removal within CWs is dependent on plant uptake and metabolism, absorption in porous media and soil, hydrolysis, photodegradation, and biodegradation. Factors related to the efficacy of CWs on the removal of fungicides, such as the type of CW, plant species, and the physicochemical parameters of fungicides, are also discussed in this paper. There are low-environmental-risk fungicides, phytohormones and other compounds, which could improve the removal performance of CW vegetation. In addition, specific parameters such as the multiple modes of action of fungicides, side effects on substrate microbial communities and endophytes, and plant physiological response were also studied. Prospects and challenges for future research are suggested under the prism of reducing the risk related to fungicides and enhancing CW performance.

No abstract

The presence of pesticide residues in groundwater, many years after their phase out in European Union verifies that the persistence in aquifer is much higher than in other environmental compartments. Currently used and banned pesticides were monitored in Northern Greece aquifers and a human health risk assessment was conducted. The target compounds were the herbicides metolachlor (MET), terbuthylazine (TER), atrazine (ATR) and its metabolites deisopropylatrazine (DIA), deethylatrazine (DEA) and hydroxyatrazine (HA). Eleven sampling sites were selected to have representatives of different types of wells. Pesticides were extracted by solid-phase extraction and analyzed by liquid chromatography. MET was detected in 100% of water samples followed by ATR (96.4%), DEA and HA (88.6%), DIA (78.2%) and TER (67.5%). ATR, DIA, DEA, HA, MET and TER mean concentrations detected were 0.18, 0.29, 0.14, 0.09, 0.16 and 0.15 μg/L, respectively. Obtained results were compared with historical data from previous monitoring studies and temporal trends were assessed. Preferential flow was the major factor facilitating pesticide leaching within the month of herbicide application. Moreover, apparent age of groundwater and the reduced pesticide dissipation rates on aquifers resulted of long-term detection of legacy pesticides. Although atrazine had been banned more than 18 years ago, it was detected frequently and their concentrations in some cases were over the maximum permissible limit. Furthermore, human health risk assessment of pesticides was calculated for two different age groups though drinking water consumption. In all examined wells, the sum of the HQ values were lower than the unity. As a result, the analyzed drinking water wells are considered safe according to the acute risk assessment process. However, the presence of atrazine residues causes concerns related with chronic toxicity, since ATR R values were greater than the parametric one of 1 × 10−6 advised by USEPA, for both age groups.

The presence of pesticide residues in groundwater, many years after their phase out in European Union verifies that the persistence in aquifer is much higher than in other environmental compartments. Factors such as limited degradation, and adsorption in phreatic horizon have resulted in frequent detection of pesticide residues and their metabolites in the saturated zone. Currently used and banned pesticides were monitored in Northern Greece aquifers and risk to human health was assessed. The target compounds were the herbicides metolachlor, terbuthylazine, atrazine and its metabolites Deisopropylatrazine (DIA), Deethylatrazine (DEA) and Hydroxyatrazine (HA). The area’s aquifer has been extensively studied over the past 20 years. Eleven sampling sites were selected in order to have representatives of different type of wells. Namely, five drinking water, two irrigation wells and four experimental boreholes located close to Greek/Turkish/Bulgarian borders were monitored and fifty-four samples were analyzed. Pesticides were extracted by solid-phase extraction and analyzed by liquid chromatography. Metolachlor was detected in 100% of water samples followed by ATR (96.4%), DEA and HA (88.6%), DIA (78.2%) and TER (67.5%). Atrazine, DIA, DEA, HA, MET and TER mean concentrations detected were 0.18, 0.29, 0.14, 0.09, 0.16 and 0.15 μg/L, respectively. Obtained results were compared with historical data from our previous monitoring studies (1999-2003 and 2010-2012) and temporal trends were assessed. Preferential flow was the major factor facilitating pesticide leaching within the month of herbicide application. Moreover, apparent age of groundwater and the reduced pesticide dissipation rates on aquifers resulted of long-term detection of legacy pesticides. Although atrazine had been banned more than 15 years ago, it was detected frequently during our monitoring campaign and their concentrations in some cases were over the maximum permissible limit. Furthermore, human health risk assessment of pesticides was calculated for two different age groups though drinking water consumption. The presence of atrazine residues causes concerns related with chronic toxicity.

Myclobutanil is a systemic fungicide belonging to the triazole group, which is frequently detected in environmental samples. Triticonazole, also a triazole fungicide, controls soil and seed-borne diseases and it is mainly used as a seed-coating pesticide. Both myclobutanil and triticonazole are considered as persistent pollutants in the environment, raising concerns about their environmental fate and ecotoxicity potential. The purpose of the present study was to investigate the efficiency of four pilot-scale horizontal subsurface flow (HSF) constructed wetlands (CWs) to remediate myclobutanil and triticonazole from artificially polluted water. Daily loading of the four CWs took place from March 2022 to July 2022 with contaminated water fortified with myclobutanil and triticonazole. Three of the CWs, encoded WMG-R, WMG-C, and WMG-U, with medium gravel (MG) as porous media and the fourth, with code name WFG-R, fine gravel (FG). Common reed (R, Phragmites australis) was planted in the WMG-R and WFG-R units, and cattail (C, Typha latifolia) in the WMG-C unit. The WMG-U unit with no plant was used as a control unit. The results showed that the removal rate follows the pattern: WFG-R (88.4%) > WMG-R > (83.4%) > WMG-C (59.3%) > WMG-U (36.6%) and WFG-R (88.5%) > WMG-C (71.0%) > WMG-R > (70.9%) > WMG-U (49.2%) for myclobutanil and triticonazole, respectively. The most significant factors influencing the fungicides’ dissipation were the porous media content and the plant species.