Mexico faces multiple water quality challenges, both in terms of the water supplied to the population as well as surface and underground water sources. Problems with drinking water supply affect the population in diverse ways, from associated health risks to high levels of intermittency in service to the poor perception of the quality of piped water – leading to high levels of bottled water consumption. In this text we explore the issue of drinking water quality in three contexts in the state of Jalisco: in Guadalajara, the state’s main urban area, in the peri-urban municipality of El Salto, and in the mid-sized city of San Juan de los Lagos. Our analysis explores drinking water regulations, the water quality monitoring undertaken by state and local authorities, access to information, as well as the actions and perceptions of water service providers. Looking at cases of indirect reuse of wastewater as well as groundwater sources with high levels of fluoride and arsenic, we argue that the foregrounding of water quality is key to illuminating social inequalities in access to water and in teasing out power relations prevailing in current hydrosocial regimes. We conclude that this hydrosocial cycle of drinking water is characterised by prioritising access to water for economic actors, facilitated by lax regulations and minimal enforcement, as well as by the systematic neglect by government authorities at all levels of the protection of watersheds and aquifers, and of water quality issues generally.

Since 2011, tourism to Mexico’s Yucatán Peninsula has been heavily impacted by large masses of sargassum seaweed washing up on the beaches, with the largest seaweed event occurring in 2019. Seaweed deters beach tourism, potentially shifting tourism inland towards other activities such as swimming in cenotes (sinkholes). Our mixed methods study combined data from surveys of visitors to the region, interviews with tourists and tour operators, thematic analysis of newspaper articles, laws and policies and analysis of water samples from a cenote to understand the environmental impact on cenotes of this shifting tourism industry. We identified intentional efforts by the tourism industry to encourage cenote tourism in response to the seaweed problem, and our survey and interview data confirmed that tourists are choosing to visit cenotes in lieu of beaches. Water samples from one tourist cenote in 2019 indicated increased pollution relative to previous years. Current regulations and management of tourist cenotes are weak, creating the potential for significant long term harm to the environment and to the water sovereignty of surrounding communities. Regulation of cenotes should be strengthened to protect these fragile karst ecosystems and to give local and indigenous residents a formal voice in the management process.

Tourist growth in Quintana Roo, Mexico has brought with it an increase of pollution by sunscreens to aquatic ecosystems, which represents an environmental risk because of the chemical components of sunscreens that can negatively affect human health and aquatic ecosystems. However, the magnitude of pollution in aquatic environments is unknown. Consequently, we sought to estimate the contamination by sunscreens based on usage and tourism statistics. Our estimate indicates that the water in Quintana Roo will receive nearly 4367.25 tons of chemicals from sunscreens used by residents and tourists over a period of 18 years (2007 to 2025). On average, each tourist stays in Quintana Roo for 3.45 days, and 89.9% of these visitors apply sunscreen, although only the 83.7% engage in water activities. Additionally, 30.4% of residents engage in water activities for an average of 1.5 days/year. We considered direct sunscreen contaminant contamination, which occurs from the application of sunscreen and subsequent water activities, as well as indirect contamination, which occurs when people wash their skin with drinking water that then enters the drainage system. Our analysis indicated that the greatest contribution of sunscreen to the karst aquifer of Quintana Roo, is direct. Chemicals dissolved in water are a danger to aquatic life and human health.

Sunscreens have spread widely into aquatic systems over the last 18 years in Quintana Roo, Mexico. This contamination is caused by intensive use as a result of leisure activities, as sunbathers apply the substances intensively (up to 83.75% of tourists and locals). Moreover, 25% of the compounds are mainly released into the water through topical products washing off. On average, 300,000 tourists arrive every week in Quintana Roo, increasing the contamination. In addition, there are no recent studies on sunscreen toxicity and the hazards this represents for the native zooplankton of Quintana Roo. In order to assess their adverse effects, acute toxicity was assessed for nine sunscreens (five non-biodegradable and four biodegradable) in four zooplankton species (Brachionus cf ibericus, Cypridopsis vidua, Diaphanocypris meridana, and Macrothrix triserialis). In total, 21 LC₅₀ values were obtained, which are the baseline values for estimating risk and for determining the expected maximum permissible concentration. Our data on toxicity to freshwater species compared to marine species indicate that freshwater species are more sensitive than marine species. In conclusion, biodegradable sunscreen posed a moderate risk, and non-biodegradable posed a high risk. Our outcomes suggested that the maximum permissible concentrations for the contamination of sunscreens were 8.00E-05 g/L for non-biodegradable and 1.60E-04 g/L for biodegradable sunscreens.

La falta de acceso a fuentes de agua segura es un problema en el Caribe Mexicano, particularmente en comunidades con irregularidad en servicios. Ante esto, la captación de agua de lluvia (CALL) podría representar una alternativa para satisfacer necesidades básicas. Sin embargo, los esquemas de implementación a menudo son verticales y jerárquicos. En este trabajo se aportó conocimiento sobre las percepciones y formas de uso del agua de lluvia, para contribuir a la toma decisiones. La información se obtuvo mediante observaciones etnográficas y encuestas a 60 representantes de hogar de una muestra de 253 viviendas en la comunidad de Puerto Morelos, Quintana Roo. El 95 % de los encuestados fueron foráneos, por lo que sus percepciones y formas de manejo del recurso fueron heterogéneas: desde sistemas simples (cubetas y tambos) hasta sistemas complejos integrados a las viviendas. En general, la CALL cuenta con una percepción positiva por parte de la población estudiada, lo cual permitiría su implementación en proyectos más estructurados que promuevan el mejoramiento de las técnicas de captación en la localidad.