Ubiquitous Detection of Artificial Sweeteners and Iodinated X-ray Contrast Media in Aquatic Environmental and Wastewater Treatment Plant Samples from Vietnam, The Philippines, and Myanmar

Abstract

Water samples from Vietnam, The Philippines, and Myanmar were analyzed for artificial sweeteners (ASs) and iodinated X-ray contrast media (ICMs). High concentrations (low micrograms per liter) of ASs, including aspartame, saccharin, and sucralose, were found in wastewater treatment plant (WWTP) influents from Vietnam. Three ICMs, iohexol, iopamidol, and iopromide were detected in Vietnamese WWTP influents and effluents, suggesting that these ICMs are frequently used in Vietnam. ASs and ICMs were found in river water from downtown Hanoi at concentrations comparable to or lower than the concentrations in WWTP influents. The ASs and ICMs concentrations in WWTP influents and adjacent surface water significantly correlated (r (2) = 0.99, p < 0.001), suggesting that household wastewater is discharged directly into rivers in Vietnam. Acesulfame was frequently detected in northern Vietnamese groundwater, but the concentrations varied spatially by one order of magnitude even though the sampling points were very close together. This implies that poorly performing domestic septic tanks sporadically leak household wastewater into groundwater. High acesulfame, cyclamate, saccharin, and sucralose concentrations were found in surface water from Manila, The Philippines. The sucralose concentrations were one order of magnitude higher in the Manila samples than in the Vietnamese samples, indicating that more sucralose is used in The Philippines than in Vietnam. Acesulfame and cyclamate were found in surface water from Pathein (rural) and Yangon (urban) in Myanmar, but no ICMs were found in the samples. The ASs concentrations were two-three orders of magnitude lower in the samples from Myanmar than in the samples from Vietnam and The Philippines, suggesting that different amounts of ASs are used in these countries. We believe this is the first report of persistent ASs and ICMs having ubiquitous distributions in economically emerging South Asian countries.

Identification of Aquifer Recharge Sources as the Origin of Emerging Contaminants in Intensive Agricultural Areas. La Plana de Castellón, Spain

“…Recent studies of ECs around the world [15,[65][66][67][68][69][70] have reported concentration values in the EWW in the same order as those found in this paper for the Vall de Uxó WWTP (Table SI-3, Supplementary material). The main differences between the EC values for the Vall de Uxó and those from previous works might be due to different consumption patterns of the citizens and the characteristics of the processes applied in the different WWTPs.…”

Monitoring of microplastics in road dust samples from Myanmar and Taiwan

“…found that high polycyclic aromatic hydrocarbon (PAH) concentrations in road dust in urban areas and fossil fuel exhaust and biomass combustion are the major sources of PAHs. The artificial sweeteners acesulfame and sucralose were clearly detected in river water from Yangon and Pathein cities (Watanabe et al, 2016). The high concentrations of toxic elements have been detected in groundwater samples from Myingyan (Bacquart et al, 2015), and soils nearby gold mining in Sagaing Region (Tun et al, 2020).…”

Water Analysis: Emerging Contaminants and Current Issues

“…Many are very stable and primarily enter the environment through treated wastewater, following direct disposal of products or through urine after consumption of products. While most studies have been carried out in Western countries, a new study published in 2016 showed significant levels of artificial sweeteners in surface waters from the Philippines (acesulfame, sucralose, cyclamate, and saccharin), in groundwater from Vietnam (acesulfame), and surface waters from Myanmar (acesulfame and cyclamate) . Most studies have focused on sucralose and acesulfame, but saccharin, cyclamate, aspartame, neotame, stevioside, glycyrrhizic acid, and neohesperidine dihydrochalcone have also been measured.…”

“…countries, a new study published in 2016 showed significant levels of artificial sweeteners in surface waters from the Philippines (acesulfame, sucralose, cyclamate, and saccharin), in groundwater from Vietnam (acesulfame), and surface waters from Myanmar (acesulfame and cyclamate). 14 Most studies have focused on sucralose and acesulfame, but saccharin, cyclamate, aspartame, neotame, stevioside, glycyrrhizic acid, and neohesperidine dihydrochalcone have also been measured. Due to their stability and high levels found in the environment (often at ppb levels), sucralose and acesulfame are recognized as potential tracers of anthropogenic inputs into environmental waters and are starting to replace caffeine for that purpose.…”