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Atrazine is a potent endocrine disruptor that increases aromatase expression in some human cancer cell lines. The mechanism involves the inhibition of phosphodiesterase and subsequent elevation of cAMP. We compared steroidogenic factor 1 (SF-1) expression in atrazine responsive and non-responsive cell lines and transfected SF-1 into nonresponsive cell lines to assess SF-1's role in atrazine-induced aromatase. We used a luciferase reporter driven by the SF-1-dependent aromatase promoter (ArPII) to examine activation of this promoter by atrazine and the related simazine. We mutated the SF-1 binding site to confirm the role of SF-1. We also examined effects of 55 other chemicals. Finally, we examined the ability of atrazine and simazine to bind to SF-1 and enhance SF-1 binding to ArPII. Atrazine-responsive adrenal carcinoma cells (H295R) expressed 54 times more SF-1 than nonresponsive ovarian granulosa KGN cells. Exogenous SF-1 conveyed atrazine-responsiveness to otherwise nonresponsive KGN and NIH/3T3 cells. Atrazine induced binding of SF-1 to chromatin and mutation of the SF-1 binding site in ArPII eliminated SF-1 binding and atrazine-responsiveness in H295R cells. Out of 55 chemicals examined, only atrazine, simazine, and benzopyrene induced luciferase via ArPII. Atrazine bound directly to SF-1, showing that atrazine is a ligand for this \"orphan\" receptor. The current findings are consistent with atrazine's endocrine-disrupting effects in fish, amphibians, and reptiles; the induction of mammary and prostate cancer in laboratory rodents; and correlations between atrazine and similar reproductive cancers in humans. This study highlights the importance of atrazine as a risk factor in endocrine disruption in wildlife and reproductive cancers in laboratory rodents and humans.

Growing evidence suggests that pesticide use may contribute to respiratory symptoms. We evaluated the association of currently used pesticides with allergic and non-allergic wheeze among male farmers. Using the 2005-2010 interview data of the Agricultural Health Study, a prospective study of farmers in North Carolina and Iowa, we evaluated the association between allergic and non-allergic wheeze and self-reported use of 78 specific pesticides, reported by ≥ 1% of the 22,134 men interviewed. We used polytomous regression models adjusted for age, BMI, state, smoking, and current asthma, as well as for days applying pesticides and days driving diesel tractors. We defined allergic wheeze as reporting both wheeze and doctor-diagnosed hay fever ( = 1,310, 6%) and non-allergic wheeze as reporting wheeze but not hay fever ( = 3,939, 18%); men without wheeze were the referent. In models evaluating current use of specific pesticides, 19 pesticides were significantly associated ( < 0.05) with allergic wheeze (18 positive, 1 negative) and 21 pesticides with non-allergic wheeze (19 positive, 2 negative); 11 pesticides were associated with both. Seven pesticides (herbicides: 2,4-D and simazine; insecticides: carbaryl, dimethoate, disulfoton, and zeta-cypermethrin; and fungicide pyraclostrobin) had significantly different associations for allergic and non-allergic wheeze. In exposure-response models with up to five exposure categories, we saw evidence of an exposure-response relationship for several pesticides including the commonly used herbicides 2,4-D and glyphosate, the insecticides permethrin and carbaryl, and the rodenticide warfarin. These results for farmers implicate several pesticides that are commonly used in agricultural and residential settings with adverse respiratory effects.

The total cultivated area in Brazil reached to 62 million ha in 2018, with the predominance of genetically modified soybean and corn (36 and 17 million ha, respectively) in no-tillage systems. In 2018, 5.3 × 10 5  Mg of active ingredient of pesticides was applied in cropfields, representing about 7.3 L of commercial product by habitant. However, the monitoring of water courses contamination by pesticides remains scarce and is based on traditional grab sampling systems. In this study, we used the grab (water) and passive sampling (Polar Organic Chemical Integrative Sampler—POCIS) to monitor pesticide contamination in the river network of a representative agricultural catchment of southern Brazil. We selected 18 sampling sites located in tributaries and in the main course of the Guaporé River, in Rio Grande do Sul State, with different land use predominance including forest, urban, and agricultural areas. Altogether, 79 and 23 pesticides were, respectively, analyzed in water and POCIS samples. The water of Guaporé River and its tributaries were highly contaminated by many pesticides, especially by four herbicides (2,4-D, atrazine, deethyl-atrazine, and simazine), three fungicides (carbendazim, tebuconazole, and epoxiconazole), and one insecticide (imidacloprid). The amount, type, and concentration of pesticides detected were completely different depending on the sampling technic used. POCIS was effective to discriminate the contamination according to the main land use of each sampling site. The monitored areas with the predominance of soybean cultivation under no-tillage tended to have higher concentrations of fungicide, while in the more diversified region, the herbicides showed higher values. The presence of five herbicides used in corn and grassland forage production was correlated with areas of integrated crop-livestock systems, in contrast to higher contamination by 2,4-D in areas of intensive production of soybean and winter cereals.

Simazine (SIM) inclusion complexes with cucurbit[n]uril, CBn, ( n = 6–8), have been studied in both aqueous solutions and solid states. NMR measurements were taken in DMSO. The solid samples were examined using Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffraction (PXRD). Molecular dynamics (MD) simulations were used to investigate the inclusion process at an atomic level and to examine the mechanism and stability of the complexes. The results showed that the SIM complexes with both CB[7] and CB [8] are highly stable in water, whereas the smaller cavity of CB[6] prevents the formation of an inclusion complex with SIM. The findings clearly demonstrate that, in addition to hydrophobic interactions, hydrogen bonding plays a significant role in stabilizing these complexes.

Nowadays, molecularly imprinted polymers (MIPs) are well established and are considered excellent materials for performing selective extractions. However, with the progressive implementation of the principles of green chemistry, it is necessary to find greener alternatives for both the synthesis and further use of MIPs in sample preparation. Accordingly, in the present work, different deep eutectic solvents (DES, both hydrophilic and hydrophobic), as an alternative to conventional organic solvents (i.e., toluene), were evaluated as porogens for the synthesis of imprinted fibers (monoliths), using fused silica capillaries as molds, for solid-phase microextraction (SPME). From this study, the polymer prepared with propazine (dummy template), methacrylic acid (monomer), ethylene glycol dimethacrylate (cross-linker), and a formic acid:L-menthol (1:1) DES (porogen) showed the best performance for selective rebinding of triazines. After optimization of the different variables involved in SPME, the new imprinted fibers were successfully applied to the extraction of target analytes (desisopropylatrazine, desethylatrazine, simazine, and atrazine) from soil sample extracts, providing relative recoveries ranging from 75.7 to 120.1%, reaching limits of detection within the range of 6.2–15.7 ng g−1, depending upon the analyte.

This study utilized cork powder as a green alternative for extractor phase using the parallel-disposable pipette extraction (Pa-DPX) method for the determination of pesticides such as atrazine, carbofuran, diuron, and simazine from aqueous environmental samples. The separation/detection was performed by HPLC–DAD. Optimization experimental conditions was achieved through univariate and multivariate designs, resulting in the following parameters: 15 mg of cork as extractor phase, 7 extraction cycles with 7.5% (m/v) NaCl in the sample, and 10 s were fixed per extraction cycle. For the desorption step, 300 µL of acetonitrile was used as solvent with 1 desorption cycle. The limit of detection and limit of quantification values were 7.5 µg L −1 and 25 µg L −1 for atrazine, carbofuran, and diuron, and 15.1 µg L −1 and 50 µg L −1 for simazine, respectively. Linear working range varied from 25 to 400 µg L −1 with coefficients of determination ( R 2 ) ≥ 0.983. The values of intraday precision varied from 4.9 to 18.1%, and those of interday precision varied from 21.3 to 32.2%. The accuracy of the method was determined through relative recoveries and the values ranged from 63.4 to 119.9%. The water environmental samples were collected at two different locations in Florianópolis, Santa Catarina, Brazil, and showed no detectable pesticides. The method presented here stands out due to the low consumption of sample and reagents, as well as the use of a renewable and biodegradable extraction phase (cork). The method is also a high-throughput alternative, due to the use of the Pa-DPX apparatus, which allows the preparation of up to five samples simultaneously.

The isotope dilution mass spectrometry (IDMS) is a highly efficient method for tackling the ion suppression in complex matrix by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), but a lack of commercial internal standards is a limiting factor for these analyses. Herein, an economical and efficient strategy for the synthesis of (13)C3-simazine via a three-step procedure was developed. The isotope-labeled internal standard was used for determination of simazine residue in soil samples. The quantitation method has a limit of detection of 0.015 μg/kg and quantitation of 0.08 μg/kg. The inter-day and intra-day precision of the method were below 4.6%. Recovery values were ranged between 92.9% and 99.2%. All the samples obtained from six provinces in China contained from 1 to 62 μg/kg of simazine.

Pesticides are ubiquitous in the catchments of the Great Barrier Reef (GBR) and regularly discharge into the nearshore waters. Effective management of pesticides requires suitable water quality guideline values (WQGVs), and further ecotoxicological data for many pesticides are needed to improve the reliability of environmental risk assessments. To help address this issue, toxicity thresholds were determined to two species of tropical marine microalgae Tisochrysis lutea and Tetraselmis sp. for a suite of herbicides detected in the GBR. Photosystem II (PSII) herbicides significantly reduced growth with no effect concentration (NEC) and 10% effect concentration (EC10) values spanning two orders of magnitude from 0.60 µg L −1 for diuron to 60 µg L −1 for simazine across both species. However, growth was insensitive to the non-PSII herbicides. The NEC/EC10 thresholds for most herbicide-microalgae combinations were greater than recent WQGVs intended to protect 99% of species (PC99); however, metribuzin was toxic to T. lutea at concentrations lower than the current PC99 value, which may have to be revisited. The toxicity thresholds for alternative herbicides derived here further inform the development of national and GBR-specific WQGVs, but more toxicity data is needed to develop WQGVs for the > 50 additional pesticides detected in catchments of the GBR.

In recent years, doveweed [ Murdannia nudiflora (L.) Brenan] has rapidly expanded across the southeastern United States, thus becoming a major concern because of its difficult eradication, limited reliable herbicides, and declining efficacy as the plant matures, thereby necessitating effective management strategies. In 2023–24, the efficacy of mesotrione (5.00 oz·acre −1 or 8.00 oz·acre −1 ), simazine (15.00 oz·acre −1 or 25.00 oz·acre −1 ), a new premix formulation of trifloxysulfuron and metcamifen (inert safener) at 1.29 oz·acre −1 as well as their combinations were assessed in turfgrass for golf course fairway, sport field, and lawn use. Late-season control of established doveweed and turfgrass safety of ‘CR-01’, ‘Tifway’ hybrid bermudagrass [ Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt Davy], and ‘Floratam’, ‘Seville’ St. Augustinegrass [ Stenotaphrum secundatum (Walter) Kuntze] in north-central and west Florida were evaluated. Except for mesotrione in 2024 [25–32 d over the threshold of 80% (DOT 80% ) doveweed control], no standalone herbicide provided acceptable doveweed control. All mesotrione and simazine tank mixes provided rapid (≤2 weeks) and persistent (>50 DOT 80% doveweed control), except for when the lower rate was combined with trifloxysulfuron and metcamifen in 2023 (31 DOT 80% doveweed control). Otherwise, trifloxysulfuron and metcamifen did not affect tank mix efficacy. All tank mixes caused rapid (1–2 weeks posttreatment) but transient (dissipating within 4 weeks) turf injury, with maxima ranging from 53% to 80% and from 54% to 65% in 2023 and 2024, respectively. Trifloxysulfuron and metcamifen additions to the lower-rate mix in 2023 reduced DOT 80% doveweed control to 35. St. Augustinegrass response varied by location. In west Florida, most treatments did not cause unacceptable phytotoxicity to ‘Floratam’. Conversely, in north-central Florida, ‘Seville’ suffered unacceptable damage across the study, including nontreated plots, likely because of external factors, with herbicides exacerbating damage. Trifloxysulfuron and metcamifen produced the most severe damage in ‘Seville’ (>37 DOT 20% turfgrass injury whenever included).

Triazine herbicides have been widely used in agriculture, but their residues can harm the environment and human health. To help monitor these, we have developed an effective immunochromatographic strip test that can simultaneously detect 15 different triazines in grain samples (including ametryn, cyprazine, atraton, prometon, prometryn, atrazine, propazine, terbuthylazine, simetryn, trietazine, secbumeton, simazine, desmetryn, terbumeton and simetone). Based on our optimization procedure, the visual limit of detection (vLOD) for these triazines was found to be 2–10 ng/mL in assay buffer, and 0.02−0.1 mg/kg in grain samples. Four different grain matrices including corn, brown rice, wheat, and sorghum were studied and the test results showed no significant differences between the 15 triazines analyzed using this method. This test is simple, convenient, rapid, and low-cost, and could be an effective tool for primary screening of triazine residues in grain samples.