Prometryn has been used in crop (e.g., corn and sorghum) field to prevent growth of annual grasses and broadleaf weeds for many years. As a moderately persistent herbicide in soil, prometryn may exert detrimental effects on environmental safety and crop production. The present study assessed the photodegradation of prometryn residues in soil by exploring a variety of factors such as soil moisture, temperature, and light exposure that potentially affect prometryn photodegradation. The dissipation rate of prometryn during a 14-day period of study was more than 90% under 15 (low pressure), 100, and 300 W (medium pressure) UV light exposure. The half-life of prometryn decay under UV light (53.5–116.4 h) was far less than that under xenon light (1131.6 h) and dark (3138.7 h) conditions. When the soil moisture (clay loam) was 60% of the field moisture capacity, it was most effective for prometryn photodegradation. The prometryn photodegradation on soil with 60% moisture level was increased with temperature and prometryn concentrations. The theoretical optimization scheme for eliminating prometryn in soil was recommended. The degraded products of prometryn under UV light and darkness were characterized using ultra high-performance liquid chromatography coupled to a linear ion trap-orbitrap hybrid mass spectrometer (UPLC-LTQ-orbitrap-MS/MS) and showed that prometryn decay in soil was through hydroxylation, dealkylation, and dethiomethylation pathways.

Adsorption of six neutral (chlorpyrifos, α-endosulfan, fenthion, parathion, parathion metyl, and cis permethrin) and six basic (pirimicarb, prochloraz, prometryn, pirimiphos ethyl, quinoxyfen, and triadimefon) pesticides was measured in ten natural soils in order to unravel the parameters influencing soil sorption. Linear regression confirmed that organic carbon content of soil is the determinant factor of soil sorption along with a secondary role of clay in the case of basic pesticides. Concerning pesticides themselves, their potential to be absorbed is governed by hydrophobic, electrostatic, and polar interactions. Electrostatic interactions can be expressed by considering the molecular fraction of positively charged species (F⁺). The combination of these parameters led to good prediction models, where the two expressions of lipophilicity, octanol-water partition (logP) and distribution coefficient (logD), showed similar performance. Finally, the role of electrostatic interactions to soil sorption and their successful expression by F⁺ parameter was further confirmed using artificial adjustment of the acidity of one soil at different pH values not covered by the natural acidity of the investigated soils.

Water and sediment samples were collected from up to 17 sites in waterways entering the Corner Inlet Marine National Park monthly between November 2009 and April 2010, with the Chemcatcher passive sampler system deployed at these sites in November 2009 and March 2010. Trace metal concentrations were low, with none occurring at concentrations with the potential for adverse ecological effects. The agrochemical residues data showed the presence of a small number of pesticides at very low concentration (ng/L) in the surface waters of streams entering the Corner Inlet, and as widespread, but still limited contamination of sediments. Concentrations of pesticides detected were relatively low and several orders of magnitude below reported ecotoxicological effect and hazardous concentration values. The low levels of pesticides detected in this study indicate that agricultural industries were responsible agrochemical users. This research project is a rarity in aligning both agrochemical usage data obtained from chemical resellers in the target catchment with residue analysis of environmental samples. Based on frequency of detection and concentrations, prometryn is the priority chemical of concern for both the water and sediments studied, but this chemical was not listed in reseller data. Consequently, the risks may be greater than the field data would suggest, and priorities for monitoring different since some commonly used herbicides (such as glyphosate, phenoxy acid herbicides, and sulfonyl urea herbicides) were not screened. Therefore, researchers, academia, industry, and government need to identify ways to achieve a more coordinated land use approach for obtaining information on the use of chemicals in a catchment, their presence in waterways, and the longer term performance of chemicals, particularly where they are used multiple times in a year.

A new sampling system has been developed for the measurement of time-averaged concentrations (TWA) and diffusion coefficients of organic micropollutants in aquatic environments. The system is based on the diffusion of targeted organic compounds through a rate-limiting membrane and the subsequent accumulation of these species in a bound, hydrophobic solid-phase material. Two separate prototype systems are described. One is suitable for the sampling of carbamates such as carbaryl, carbofuran, 3-hydroxycarbofuran, baygon, propham, clorpropham, and the other one for s-triazines such as atrazine, prometryn, propazine, simazine, terbuthylazine, terbutryn, metribuzin, cyanazine, and metamitron pesticides. The systems use solid-phase material (47-mm C₁₈ Empore disk) as the receiving phase but are fitted with rate-limiting membranes of either polysulfone or polycarbonate. For the two designs investigated, the cumulative uptake of all target analytes was considered over exposure periods of 7 days. The determined sampling rates ranged from 0.1323 to 0.0465 L day⁻¹ with both membranes. The best system was the one with the polysulfone membrane allowing a better cumulative uptake.

Triazines and their degradation products are transported to the aquatic environment, and once there, the probability to reach the marine environment is very high. In this paper, solid phase extraction (SPE) and extraction by matrix solid phase dispersion (MSPD) to analyse nine triazines (ametryn, atrazine, cyanazine, prometryn, propazine, simazine, simetryn, terbuthylazine and terbutryn) and eight degradation products (desethylatrazine, desethyldesisopropylatrazine, desethyl-2-hydroxyatrazine, desethylterbuthylazine, desisopropylatrazine, desisopropyl-2-hydroxyatrazine, 2-hydroxyatrazine and 2-hidroxyterbuthylazine) in seawater and marine sediments samples were used. The analysis was carried out using liquid chromatography with tandem mass spectrometry (LC-ESI-MS/MS). The methods were optimized and validated to achieve a selective and sensitive determination of the analytes from different sample, regardless of its complexity. Under the optimum conditions, the proposed methods provided adequate limits of quantification (0.05–0.45 μg L⁻¹ and 0.23–4.26 μg kg⁻¹ in seawater and marine sediments, respectively). Intra- and inter-day relative standard deviation were below 1.41% for all compounds. Recoveries were evaluated, and acceptable values that ranged from 87.5–99.4 and 60.9–99.7% for the seawater and sediment samples, respectively, were obtained. The proposed methods were applied to the analysis of the target compounds in seawater samples and marine sediments from a coastal area of Galicia (NW of Spain).