The threat of global climate change to the world’s water resources has jeopardized access to clean drinking water across the world and continues to devastate biodiversity and natural life globally. South Africa operates as a useful case study to understand and analyze the effectiveness of public policy responses to the perils of climate change on issues of water access and ecosystem preservation. After the new South African Constitution was enacted in 1997, protecting water resources and ensuring their equitable distribution across the nation’s population was a paramount goal of the young democratic government. The National Water Act was passed in 1998, nationalizing the country’s water infrastructure and putting in place programs seeking to ensure equitable distributive and environmental outcomes. Thus far, it has failed. Access to South Africa’s water resources is as stratified as access to its economy; its aquatic ecosystems remain in grave danger; and many of the same problems of South Africa’s Apartheid era still plague its efforts to create an equitable water system. Decision-making power continues to be concentrated in the hands of the wealthy, at the expense of historically marginalized groups, whose voices are still not adequately heard. Corporate actors still exert undue influence over legislative policy that favors economic growth over environmental sustainability. The looming threat of climate change is exponentially increasing the chances of disasters like Cape Town’s 2018 feared ‘Day Zero’. The National Water Act’s noble intentions were never actualized, and therefore the people of South Africa remain in serious danger of acute and chronic threats to their water supply.

Plasticizers are plastic additives used to enhance the physical properties of plastic and are ubiquitous in the environment. A class of plasticizer compounds called phthalate esters that are not fully eliminated in wastewater treatment facilities are relevant to the ecological health of downstream ecosystems and urban areas due to their ecotoxicity, tendency for soil accumulation, and the emerging concern about their effects on public health. However, plasticizer concentrations in a constructed wetland environment have rarely been studied in the United States, prompting the need for a method of plasticizer quantification in the Tres Rios Constructed Wetlands which are sustained by the effluent of the 91st Avenue Wastewater Treatment Plant in Phoenix, Arizona. The concentrations of four common plasticizer compounds (dimethyl: DMP, diethyl: DEP, di-n-butyl: DnBP, and bis(2-ethylhexyl): DEHP phthalate) at five sites across the wetland surface water were quantified using solid-phase extraction followed by gas chromatography coupled with mass spectrometry (GC/MS). The sampling period included four sample sets taken from March 2022 to September 2022, which gave temporal data in addition to spatial concentration data. Quantification and quality control were performed using internal standard calibration, replicate samples, and laboratory blanks. Higher molecular weight phthalates accumulated in the wetland surface water at significantly higher average concentrations than those of lower molecular weight at a 95% confidence level, ranging from 8 ng/L to 7349 ng/L and 4 ng/L to 27876 ng/L for DnBP and DEHP, respectively. Concentrations for dimethyl phthalate and diethyl phthalate were typically less than 50 ng/L and were often below the method detection limit. Average concentrations of DnBP and DEHP were significantly higher during periods of high temperatures and arid conditions. The spatial distribution of phthalates was analyzed. Most importantly, a method for successful ultra-trace quantification of plasticizers at Tres Rios was established. These results confirm the presence of plasticizers at Tres Rios and a significant seasonal increase in their surface water concentrations. The developed analytical procedure provides a solid foundation for the Wetlands Environmental Ecology Lab at ASU to further investigate plasticizers and contaminants of emerging concern and determine their ultimate fate through volatilization, sorption, photodegradation, hydrolysis, microbial biodegradation, and phytoremediation studies.