Sepideh Nasrollahpour1, Natalia Klanovicz1,2, Pratishtha Khurana1, Satinder Kaur Brar1*
1Department of Civil Engineering, Lassonde School of Engineering, York University, Toronto, Canada.
2Department of Chemical Engineering, Escola Politecnica, University of Sao Paulo, Sao Paulo, Brazil.
Climate Change and Its Implications
Climate change, caused by rising greenhouse gas emissions, is raising global temperatures, altering precipitation patterns, and increasing the frequency of extreme weather events. These alterations have a significant impact on the distribution and behavior of pollutants in the environment. Increased temperatures, for example, can accelerate the chemical and biological breakdown of pollutants, affecting their persistence and toxicity. Furthermore, changed precipitation patterns might influence pollutant transport pathways, causing redistribution across several environmental compartments such as water, soil, and air.
Emerging Contaminants: A Growing Concern
Emerging contaminants, such as medicines, personal care products, nanomaterials, and microplastics, are compounds that are not routinely monitored in the environment but have the potential to affect the environment and human health. The behavior and fate of these toxins are frequently unknown, making it difficult to forecast how they may interact with changing environmental circumstances caused by climate change.
Interactions between Climate Change and Emerging Contaminants
The relationship between climate change and the water cycle is critical, as it influences the mobility, distribution, and concentration of ECs across vast areas. When climate change causes more rain and floods, it leads to more runoff and leaking of pollutants from land to water. For example, heavy rains and flooding can overwhelm wastewater treatment systems, leading to the discharge of untreated or partially treated effluents containing ECs into water bodies. This spreads ECs further and increases their levels in rivers and underground water sources, which are used for drinking and can harm aquatic life, subsequently incorporating these contaminants into the human food chain [1].
Climate change-induced temperature changes can affect the behavior of ECs, altering their persistence, bioavailability, and toxicity. Elevated temperatures can both accelerate the degradation of some contaminants and increase the stability of others, as well as cause the volatilization of certain compounds. This shifts their distribution across air, water, and soil, creating new exposure pathways. Additionally, the melting of polar ice due to higher temperatures releases ECs long trapped in ice, reintroducing them into the environment and posing new risks to both wildlife and human health [2]. Moreover, variations in temperature, moisture, and other climatic factors can boost or hinder microbial activities, directly affecting the biodegradation and toxicity of ECs. For example, increased temperatures and UV exposure may expedite the breakdown of some chemicals, reducing their environmental persistence, or create new toxic by-products [3].
The agricultural sector is particularly vulnerable, as climate change can affect the prevalence and distribution of contaminants in soil and water, impacting crop quality and food safety. This not only poses health risks but also economic challenges for farmers and communities dependent on agriculture It's important to note that the impact of climate change and emerging contaminants is not uniformly distributed. Urban areas, with their higher industrial and vehicular emissions, might face different challenges compared to rural areas, where agricultural runoff plays a significant role.
In conclusion, the complex relationship between climate change and ECs not only worsens environmental threats but also has significant implications for human health, affecting exposure pathways and risks. Changes in water quality and availability, as well as changes in agricultural practices due to climate variability, can directly impact human exposure to waterborne and foodborne contaminants [4]. Addressing these challenges requires a multidisciplinary approach, emphasizing the importance of enhancing monitoring and research to understand the behavior, fate, and impacts of ECs under changing climatic conditions. Developing effective mitigation strategies that consider the challenges of climate change is crucial for protecting environmental and public health. There are costs associated with mitigating the effects of ECs, such as upgrading wastewater treatment plants, implementing new water quality standards, waste management practices, and emissions controls. Moreover, the implementation of adaptive and forward-looking policies and regulations is essential to manage the evolving threats posed by both climate change and contaminants efficiently.
References
[1] S. Bolan et al., “Impacts of climate change on the fate of contaminants through extreme weather events,” Science of The Total Environment, vol. 909, p. 168388, Jan. 2024, doi: 10.1016/J.SCITOTENV.2023.168388.
[2] S. A. Snyder et al., “Climate Change Impacts on Emerging Contaminants,” pp. 311–329, 2012, doi: 10.1007/978-1-0716-2466-1_261.
[3] K. Mukherjee, “Climate change as a driving factor for emerging contaminants,” Present Knowledge in Food Safety: A Risk-Based Approach through the Food Chain, pp. 303–308, Jan. 2023, doi: 10.1016/B978-0-12-819470-6.00048-2.
[4] K. E. Jones et al., “Global trends in emerging infectious diseases,” Nature 2008 451:7181, vol. 451, no. 7181, pp. 990–993, Feb. 2008, doi: 10.1038/nature06536.