Metazachlor traces in the main drinking water reservoir in Luxembourg: a scientific and political discussion

Abstract

This discussion is centralized around an incident that took place in the Belgian village Witry the 17th of September 2014. A tractor accident led to the discharge of an aqueous solution of the herbicide metazachlor into the creek Moyémont that further merges into the river Sûre. About 20 km downstream, these waters supply the lake of the Upper-Sûre in Luxembourg, the biggest artificial lake and the main drinking water reservoir in the country. The evolution of the concentration of metazachlor and its metabolite 479M08 was partially tracked down from the river Sûre to the dam situated in the east. At this location, the SEBES drinking water treatment plant has its raw water intake from the lake. After this incident, substantial pollution by the metazachlor breakdown product 479M08 of the lake and of some other groundwater sources in the Grand Duchy was revealed due to a strong monitoring program that was started by the national water authority (AGE). This was for example the case in the SEBES groundwater resource Scheidhof close to Luxembourg City. There is also the reason to assume that contamination by 479M08 existed already in the lake before the incident in Witry, certainly due to agricultural activity. In the second part of this discussion, these perceptions are placed in their appropriate political context. Indeed, the quality of groundwater and drinking water is strongly regulated in the European Union and in Luxembourg. Compound 479M08, for instance, is submitted to a maximum parametric value of 0.1 µg/L in Luxembourg. Several short- and longtime political measures had to be taken to guarantee the wholesomeness of the water from a legal point of view.

Occurrence and Distribution of Pharmaceuticals and Their Transformation Products in Luxembourgish Surface Waters

“…Luxembourg has vineyards lining the Moselle River, agricultural activity in the north of the country, and a population largely centered in the capital, which together brings in a significant and varied chemical load into the environment. Previous studies have reported the presence of analgesics, antimicrobials, and estrogens in Luxembourgish surface water. − Aside from providing data on the level of xenobiotics in Luxembourgish waters, these studies have also demonstrated that the presence of these chemicals is due to inputs from land use, accidental spillage, wastewater effluent, and long-range transport. ,− Other studies have reported the measurement of 14 pesticides and their transformation products (TPs) in both surface water and drinking water. , The Luxembourg Water Management Agency (Administration de la Gestion de l’Eau, hereafter AGE), in compliance with the European Union Water Framework Directive (WFD), monitors different organic contaminants in Luxembourgish surface water . Among the 92 compounds included in the targeted analysis performed by AGE, five are pharmaceuticals: carbamazepine, diclofenac, ibuprofen, ketoprofen, and lidocaine, while the rest the targeted organic contaminants are pesticides and related compounds.…”

Occurrence and Distribution of Pharmaceuticals and their Transformation Products in Luxembourgish Surface Waters

“…The following data-dependent (dd-)MS2 settings (in display order of instrumental acquisition method) were used: resolution (120,000 at m/z 200), automatic gain control (AGC) target (1.0×10 6 ), maximum injection time (IT): (70 ms), and scan range (m/z=60-900). For the selected ion monitoring dd-MS2/ddSIM the following were used: resolution (30,000 at m/z 200), AGC target (5.0×10 5 ), maximum IT (70 ms), loop count (5), Top N (5), isolation window (1.0 Da), (N)CE (30). Lastly, the following dd settings were used: minimum AGC target (8.0×10 3 ), intensity threshold (1.1×10 5 ), apex trigger (4-6 s), exclude isotopes (On), and dynamic exclusion (10.0 s).…”

Occurrence and Distribution of Pharmaceuticals and their Transformation Products in Luxembourgish Surface Waters

“…[1][2][3] Aside from providing data on the level of xenobiotics in Luxembourgish waters, these studies have also demonstrated that the presence of these chemicals are due to inputs from land use, accidental spillage, wastewater effluent, and long range transport. 1,[3][4][5][6] Other studies have reported the measurement of 14 pesticides and their transformation products (TPs) both in surface water and drinking water. 3,7 The Luxembourg Water Management Agency (Administration de la Gestion de l'Eau, hereafter AGE), in compliance with the European Union Water Framework Directive (WFD), monitors different organic contaminants in Luxembourgish surface water.…”

“…Considering the previously reported presence of chemicals in Luxembourg's environment 2,[4][5][6][7] and the widespread use of chemicals in daily life, a large number of compounds could be considered as potential environmental pollutants in Luxembourg.…”