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The study conducted in the state of Colima, western Mexico, aimed to assess the 1) occurrence, 2) temporal variability, 3) spatial variability, and 4) potential risk for honeybees and human consumption of pesticide-contaminated honey. For that purpose, 48 pesticides were determined in bees and their honey during both dry and wet seasons. The research considered two variables: land use categorization (irrigated agriculture, rainfed agriculture, grassland, and forest area) and location (coastal, valley, and mountain). Bee and honey samples were collected, pre-treated using solid-phase extraction (SPE), and analyzed using LC-MS/MS and GC-MS techniques. Occurrence: of the total number of pesticides, 17 were detected in the bee samples and 12 in the honey samples. The pesticides with the highest concentrations in the bee samples were glufosinate ammonium, picloram, and permethrin, while in the honey samples, picloram, permethrin, and atrazine were the most prevalent. Temporal variability: analyses revealed significant differences between dry and wet seasons for glufosinate ammonium and DEET in bee samples and only for glufosinate ammonium in honey samples. Spatial variability: analyses showed a trend in the number of detected pesticides, with irrigated agriculture areas having the highest detection and grassland areas having the least. The human potential risk assessment of contaminated honey consumption indicated no risk. The bee's potential risk for consumption of pesticides contaminated honey revealed chronic effects due to permethrin in a general scenario, and carbofuran, diazinon and permethrin in the worst scenario, and potential risk of acute effects by permethrin. The findings of this study contribute to understanding the contamination levels of pesticides in bees and their honey, emphasizing the importance of monitoring and mitigating the adverse effects of pesticide exposure on bee populations and environmental health.

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The intensive use of pesticides in Mexican agriculture has contributed significantly to the increase in food production, but at the same time represents potential risk to biota. This situation creates a dilemma between the need to increase food production and the preservation of the environment and human health. Aquatic invertebrates play a vital role in the balance of aquatic ecosystems but are sensitive to pesticides contamination. The sensitivity of aquatic invertebrates to pesticides contamination has led them to be used to assess the potential impact of this contamination on aquatic ecosystems. In the present study, conducted in the Ayuquila-Armería basin, the following aims were achieved: 1) quantifying the presence of 20 pesticides in river sediments, 2) assessing the spatiotemporal distribution of pesticides in river sediments, 3) determining the potential risk to aquatic invertebrates, and 4) prioritizing pesticides based on their potential risk. Twelve pesticides were consistently quantified in 192 river sediments samples. The pesticides with the highest concentrations were ametrine, malathion and picloram. The temporal analysis showed seasonality in pesticide concentrations, with higher detection frequencies during the wet season. The risk assessment showed that aquatic invertebrates may be affected by the concentrations of carbofuran, malathion, diazinon and ametrine. Pesticides prioritization identified ametrine, carbofuran, and diazinon as major concerns based on the methodology that considers the Frequency and Extent of Exceedance. This study provides valuable insights into the current pesticides scenario in the Ayuquila-Armería River sediments. The findings underscore the need for sustainable alternatives to mitigate the ecological risks associated with pesticides contamination in this aquatic ecosystem.

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Aquatic ecosystems worldwide are strongly influenced by the productive activities of a region. These activities can generate pollution by compounds with little-known or unknown characteristics and without regulation. Emerging contaminants are a group of compounds that have worldwide begun to be frequently detected in the environment, raising concern about their possible adverse effects on human and environmental health. Thus, it is important to generate a broader panorama of the dissemination of contaminants of emerging concern in the environment, implement actions to regulate their usage. This study aims to evaluate the occurrence and temporal distribution of oxandrolone and meclizine in surface water, sediments, tilapia muscle, and otter feces of the Ayuquila-Armería river, Mexico. Oxandrolone was detected in 55 % of the total analyzed samples, while meclizine was present in 12 %. In surface water, oxandrolone was present in 56 % of the samples, while meclizine in 8 %. In sediments, oxandrolone was detected in 45 % and meclizine was not detected. In tilapia muscle, oxandrolone was present in 47 % of samples and meclizine was not detected. In otters feces samples, oxandrolone and meclizine were present in 100 %. Regardless of the season (wet or dry), oxandrolone was detected in all four sample types, while meclizine was only detected in surface water and otter feces samples. Oxandrolone in the aquatic ecosystem of the Ayuquila-Armería basin showed that season variation generates a significant effect on their concentrations, especially in surface water and sediments. Meclizine did not show temporal variations either in seasons or between years. Particularly, oxandrolone concentrations presented an influence with respect to the sites that present continuous residual discharges to the river. In this sense, this study could be considered as a starting point for further routine monitoring of emerging contaminants to support regulation policies regarding their use and disposal.

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Pesticide usage has contributed to increasing food production; it has also caused them to be found in ecosystems inducing adverse effects on biota. Fish are the most abundant and diverse vertebrates in the world and are of great importance both economically and ecologically. Some fishes are indicators of the environmental quality of aquatic ecosystems and provide insight as to how pollutants might influence public health. The tilapias species can be considered biomonitors because they present little displacement representing the contamination level of a site. This study aimed at three goals: (1) to determine the concentration of 20 pesticides in tilapia muscle in the Ayuquila-Armería basin, (2) to describe the spatiotemporal variation of analytes and (3) to evaluate the risk of consuming contaminated fish. The presence of 11 pesticides was determined. Ametrine, glyphosate and malathion concentrations showed significant differences by season. The risk assessment showed that the consumption of tilapia muscle from the Ayuquila-Armería basin does not represent a risk for the population. Diazinon concentrations were relatively low compared to the other pesticides concentrations, but its toxic characteristics were the ones that most negatively influenced the risk assessment. The results obtained are relevant from the social and economic points of view.

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The pesticides used have contributed to increasing food production; it has also caused them to be found in most ecosystems and have negative effects on biota. The neotropical otter (Lontra longicaudis) is vulnerable to pesticide accumulation and is characterized by being elusive, so it is necessary to address the use of indirect techniques that evaluate its populations' state in an efficient, logistically simple, and non-invasive way. This study aimed to determine the concentration of 20 pesticides in neotropical otter feces in the Ayuquila-Armería basin and to describe the spatiotemporal variation of these pesticides. The presence of 11 pesticides was determined. Imazalil, picloram, and malathion the pesticides with the highest concentrations; emamectin, λ-cyhalothrin, methomyl, and picloram were present in all samples. Emamectin was the only pesticide that presented significant differences concerning the temporality of the samplings, presenting higher concentrations in the wet season. Molinate concentrations showed significant differences concerning the location of the sampling sections in the basin; the lower part of the basin presented higher concentrations. The distribution of the populations of L. longicaudis in the Ayuquila-Armería basin does not respond to the degree of contamination by pesticides in surface waters or to the proximity to agricultural activities, and this in places with evident chemical and organic contamination and human presence. The use of otter feces for pesticide monitoring is an accepted non-invasive method to assess the degree of exposure and can be used to determine sites with pollution problems.

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The hollow fiber liquid-phase microextraction allows highly selective concentration of organic compounds that are at trace levels. The determination of those analytes through the supercritical fluid chromatography usage is associated with many analytical benefits, which are significantly increased when it is coupled to a mass spectrometry detector, thus providing an extremely sensitive analytical technique with minimal consumption of organic solvents. On account of this, a hollow fiber liquid-phase microextraction technique in two-phase mode combined with supercritical fluid chromatography coupled to mass spectrometry was developed for quantifying 19 multiclass emerging contaminants in water samples in a total chromatographic time of 5.5 min. The analytical method used 40 µL of 1-octanol placed in the porous-walled polypropylene fiber as the acceptor phase, and 1 L of water sample was the donor phase. After extraction and quantification techniques were optimized in detail, a good determination coefficient (r2 > 0.9905) in the range of 0.1 to 100 µg L-1, for most of the analytes, and an enrichment factor in the range of 7 to 28,985 were obtained. The recovery percentage (%R) and intraday precision (%RSD) were in the range of 80.80-123.40%, and from 0.48 to 16.89%, respectively. Limit of detection and quantification ranged from 1.90 to 35.66 ng L-1, and from 3.41 to 62.11 ng L-1, respectively. Finally, the developed method was successfully used for the determination of the 19 multiclass emerging contaminants in superficial and wastewater samples.

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INTRODUCTION: Annona purpurea is a species known in Mexico as "cabeza de negro". In folk medicine A. purpurea root is used to treat patients with kidney diseases and cancer. Our recent studies demonstrated that this species contains five acetogenins named annopurpuricins A-E, which are active against tumoural cell lines in a subnanomolar range. OBJECTIVE: To develop an analytical method using a high-performance liquid chromatography diode array detector (HPLC-DAD) to quantify annopurpuricins A-E in different A. purpurea root samples. METHODOLOGY: To quantify the five annopurpuricins A-E a sample treatment was carried out, which consisted of fractionation by means of cold and hot maceration; using solvents of ascending polarity: hexane, dichloromethane, methanol and water. The resulting extracts were subject to HPLC-DAD analysis. The optimised chromatographic separation on a XBRIDGE C18 column achieved separation of all compounds in around 30 min. RESULTS: The developed method was validated according to ICH (International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use) validation guide. The developed analytical method was found fast, economic, robust, sensitive, linear and precise. The dichloromethane extract of A. purpurea contains annopurpuricin A in quantities 2- to 25-fold higher than annopurpuricins B-E. This optimised method identified and quantified five annopurpuricins, highly bioactive molecules, in A. purpurea root. CONCLUSIONS: The fingerprint of the dichloromethane extracts of A. purpurea was obtained at 210 nm. The results analysis allowed to quantify annopurpuricins A-E that are present in different collection batches of medium polarity extracts. After data analysis, annopurpuricin A could be establish as the metabolite marker of the root of the species.

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A new polymorphic form of the title compound, C12H10O4, is described in the ortho-rhom-bic space group Pbca and Z = 8, as compared to polymorph I, which crystallizes in the monoclinic space group C2/c and Z = 8 [Li et al. (2012). Chin. J. Struct. Chem. 31, 1003-1007.]. In polymorph II, the coumarin ring system is almost planar (r.m.s. deviation = 0.00129 Å). In the crystal, mol-ecules are connected by Csp 3-H⋯O and Car-H⋯O hydrogen bonds, forming mol-ecular sheets linked into zigzag shaped layers along the b-axis direction. The three-dimensional lattice is assembled through stacking of the zigzag layers by π-π inter-actions with a centroid-to-centroid distance of 3.600 (9) Šand anti-parallel C=O⋯C=O inter-actions with a distance of 3.1986 (17) Å, which give rise to a helical supra-molecular architecture.

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Abstract A selective, sensitive and precise reversed phase HPLC-DAD method was developed and validated for the simultaneous determination of six phenolic acids in the aqueous extract and their hydrolyzed forms prepared from Solanum elaeagnifolium Cav., Solanaceae, Ampelocissus acapulcensis (Kunth) Planch., Vitaceae, or Brosimum alicastrum Sw., Moraceae. The new method showed good linearity (r > 0.999) in a relatively wide concentration range (0.5-100 mg/l). The limits of detection and quantification for the compounds were in the range of 0.097-0.467 mg/l and 0.097-0.496 mg/l, respectively. The recoveries of compounds were calculated in three different concentrations in the range of 88.07-109.17% and matrix effect was less than 5% for all phenolic acids. Finally, our developed HPLC method is simple, reliable and successfully applied to identify and quantify the phenolic acids in complex aqueous extracts from medicinal species, that can be useful for the analysis of infusions that people consume in folk medicine.

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Annona purpurea, known in Mexico as "cabeza de negro" or "ilama", belongs to the Annonaceae family. Its roots are employed in folk medicine in several regions of Mexico. Taking that information into account, a chemical and biological analysis of the components present in the roots of this species was proposed. Our results demonstrated that the dichloromethane (DCM) extract was exclusively constituted by a mixture of five new acetogenins named annopurpuricins A-E (1-5). These compounds have an aliphatic chain of 37 carbons with a terminal α,ß unsaturated γ-lactone. Compounds 1 and 2 belong to the adjacent bis-THF (tetrahydrofuran) α-monohydroxylated type, while compounds 3 and 4 belong to the adjacent bis-THF α,α'-dihydroxylated type; only compound 5 possesses a bis-epoxide system. Complete structure analysis was carried out by spectroscopy and chemical methods. All compounds were evaluated for their antiproliferative activity on three human tumor cell lines (MSTO-211H, HeLa and HepG2). Compounds 1-4 inhibited significantly the growth of HeLa and HepG2 cells, showing GI50 values in the low/subnanomolar range, while 5 was completely ineffective under the tested conditions. The investigation of the mechanism of action responsible for cytotoxicity revealed for the most interesting compound 1 the ability to block the complex I activity on isolated rat liver mitochondria (RLM).

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