Analysis of sunscreens and antibiotics in groundwater during the Covid-19 pandemic in the Riviera Maya, Mexico

Ammonium depletion associated with the COVID-19 pandemic in the Mexican Caribbean

The Mexican Caribbean contributes significantly to Mexico's gross national product. The number of tourists declined from 16.7 million in 2019 to 8.8 million in 2020 due to the COVID-19 pandemic, with a rapid recovery of 13.5 million in 2021. Wastewater discharge is the primary contamination source associated with the tourism sector's demand for goods and services. Water quality could improve due to fewer tourists arriving during the COVID-19 sanitary emergency. This study aimed to quantify ammonium concentrations at eleven locations to evaluate water quality during the sanitary restriction due to the pandemic in the Mexican Caribbean. The ammonium concentrations were 85 % (Nov-2019), 89 % (Feb-2020), and 86 % (Feb-2021) higher than in Nov-2020, where six of the eleven sampled stations were below the detection limit (0.15 μM). Lower ammonium concentrations coincide with the sanitary restriction period and a decrease in affluent tourists.

Recent developments in sunscreens based on chromophore compounds and nanoparticles

Sunscreen formulations have undergone significant advancements in recent years, with a focus on improving UV radiation protection, photostability, and environmental sustainability. Chromophore compounds and nanoparticles have emerged as key components in these developments. This review highlights the latest research and innovations in chromophore compounds and nanoparticle-based sunscreens. It discusses the role of nanoparticles, such as zinc oxide and titanium dioxide, in scattering and absorbing UV radiation while remaining cosmetically acceptable. Chromophore compounds, encapsulated in nanoparticles, are explored for their potential to enhance UV protection by absorbing specific wavelengths of light. Additionally, advances in photo-stability, broad-spectrum protection, antioxidant inclusion, and biodegradability are discussed. The evolving landscape of sunscreen technology aims to provide more effective and environment-friendly solutions for safeguarding skin from the sun's harmful effects.