Bisphenol A (BPA), 4-nonylphenol (4NP), estradiol (E₂), and ethinylestradiol (EE₂) are considered as endocrine disruptors or mutagens. These compounds are commonly called endocrine disrupter chemicals (EDCs). BPA and 4NP are widely used as plastic additives, lacquers, resins, or surfactants, while E₂ is one of the predominant female sex hormones during the reproductive years, and EE₂ is an estrogen derived from estradiol, used in the production of contraceptive pills. All of these can be usually found in wastewater. In Mexico, it is common for water from rivers, lakes, and canyons to be reused for different purposes. Unfortunately, there is little information on the concentration of many of the pollutants present in such bodies of water. To determine the presence of these compounds in samples of wastewater in the Apatlaco River, an accurate and reproducible method was developed by coupling gas chromatography to mass spectrometry (GC-MS). A solid-phase extraction with Chromabond RP-18 cartridges was carried out, and the elution was performed with an acetone/methanol mixture. After isolation, the solvent was removed and a silylation step was carried out using N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA). Recoveries for spiked samples were between 71.8% and 111.0%. The instrumental limits of detection (IDL) ranged between 24.7 and 37.0 ng mL⁻¹. In total, 16 samples were taken in 2015 at the microbasin of the Apatlaco River, located in the state of Morelos. The maximum concentrations found were 4NP (85.5 ng mL⁻¹), BPA (174.6 ng mL⁻¹), E₂ 103.6 (ng mL⁻¹), and EE₂ (624.3 ng mL⁻¹).

In this study, two hormones 17β-estradiol (E₂) and 17α-ethynylestradiol (EE₂), and three phenolic compounds, bisphenol A (BPA), 4-N-nonylphenol (4-NP) and 4-tert-octylphenol (4-t-OP), were determined in surface water in the Cuautla River at the State of Morelos during the dry-season in Mexico. The endocrine disrupting compounds (EDCs) were extracted from water samples using solid-phase extraction (SPE) with end-capped C₁₈, and then the extracts were chemically derivatized to TMS (trimethylsylane)-compounds and analyzed by gas chromatography coupled to mass spectrometry (GCMS). The most abundant compound was BPA (22.46 ± 30.17 ng L⁻¹), followed by 4-t-OP (11.24 ± 11.76 ng L⁻¹), 4-NP (7.53 ± 14.88 ng L⁻¹), EE₂ (2.37 ± 4.36 ng L⁻¹) and E₂ (0.97 ± 1.82 ng L⁻¹). The residual amounts of target compounds could either reach stream surface water from direct domestic wastewater discharges, conventional wastewater treatment plant or can be a result from the use of agrochemicals in crop areas. The EDCs in Cuautla River exerted a high pressure on the aquatic ecosystem because their presences in surface water caused medium and high potential ecological risk. Besides, it was found that aquatic organisms were exposed to estrogenic activity.

This study evaluated the distribution and potential estrogenic risk of the presence of bisphenol A (BPA), 4-nonylphenol (4NP), naproxen (NPX), ibuprofen (IBU), 17-β-estradiol (E₂) and 17-α-ethinylestradiol (EE2) in water and sediments of the Apatlaco river micro-basin (Morelos, Mexico). The concentration of the determined compounds ranged between <LOD to 86.40 ng·L⁻¹ and 1 ng·L⁻¹).

The aim of this work was to determine Fulvic Acids (FAs) in sediments to better know their composition at the molecular level and to propose substructures and structures of organic precursors. The sediment samples were obtained from a priority area for the conservation of ecosystems and biodiversity in Mexico. FAs were extracted and purified using modifications to the International Humic Substances Society method. The characterization was carried out by 1D and 2D nuclear magnetic resonance (NMR) and high-performance liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) in positive (ESI⁺) and negative (ESI⁻) modes. Twelve substructures were proposed by the COSY and HSQC experiments, correlating with compounds likely belonging to lignin derivatives obtained from soils as previously reported. The analysis of spectra obtained by HPLC-ESI-MS indicated likely presence of compounds chemically similar to that of the substructures elucidated by NMR. FAs studied are mainly constituted by carboxylic acids, hydroxyl, esters, vinyls, aliphatics, substituted aromatic rings, and amines, presenting structures related to organic precursors, such as lignin derivatives and polysaccharides.

Endocrine-disrupting compounds are compounds of pharmaceutical, lifestyle and industrial origin. The partial remotion of endocrine-disrupting compounds (EDCs) contained in wastewater waste from municipal or industrial origin contributes to their frequent detection in surface water of rivers, lakes and costal zones, as well as they have also been found in groundwater. This chapter contemplates studies of some compounds found in rivers in several environmental compartments in México. The topics that will be included in this chapter involves the detection of traces of EDC in surface and groundwater by chromatographic with mass spectrometric simple and tandem techniques, remotion with nanomaterials, degradation with advanced oxidation processes and risk human exposure and ecological assessment.