Background
Accurately predicting the future is impossible. Nonetheless the chances of somethings happening are greater than others. For example, the World population will continue to increase over the next few decades from 8.2 billion to around 10.3 billion by 2080. This is so-called ‘global megatrend’ in population size will also be a key driver of several other megatrends (defined here as long term changes that have major global impacts on society, economy, culture and geopolitics), including efforts to produce more food and potable water, build more infrastructure (roads and vehicles, railways and trains, airports and aircraft, waste disposal and water purification systems, communication systems and data storage, etc.) and ensure greater energy provision. A vast array of chemicals will be needed to support each of these developments. From 1950 to 2017, global chemical production increased 50 fold to meet expanding needs. By 2030 it is expected to double again. More than half of this production now occurs in Asia. Currently, 350,000 chemicals have been registered for use, with approximately 2000 new chemicals added each year. Inevitably, a proportion of these chemicals enters the environment accidentally or through intentional release. A consequence of past pollution is that there are now thousands of examples of heavy metals, pesticides, oil, synthetic industrial chemicals, pharmaceuticals, microplastics and nanomaterials harming ecosystems and triggering diseases in humans. Of the 80,000 most widely used chemicals, less than 1% have been subject to regulatory toxicity testing and control. The toxicity of the remainder is uncertain. Added to this, a megatrend in plastic production (a 70% rise is predicted by 2040) is likely to result in the further release of microplastics into the environment.
Examples of chemicals that may be released in increasing amounts in the coming years include:
Lithium, cobalt, nickel, manganese & rare earth metals used in batteries, computers, drones and a wide range of electronic devices.
PFPE (and other PFAS), used in, lubricants, sealants, 3D printing.
Speciality chemicals (e.g. 1, 4 Dioxane, DecaBDE) used in personal care products, as flame retardants, in the construction industry and as industrial cleaners.
Pharmaceuticals (veterinary and medical) used as analgesics, antibiotics, chemotherapeutic agents, antihypertensives, cholesterol control (statins), weight-loss drugs, etc.
Advanced materials (e.g. nanomaterials, perovskites (used in solar cells), silicon carbide (used in electronics), metal-organic frameworks (MOFs) used in gas storage, as catalysts, drug delivery systems, water treatment systems.
Bio-based biodegradable chemicals used in eco-friendly products (corn starch, algae, plant oils etc.) and Polylactic acid (PLA) and polyhydroyalkanoates (PHA) incorporated in packaging and textiles.
Plastics used in a diverse array of products (leading to microplastic release and which incorporate plasticisers such as Bisphenol S).
Industrial gases and basic chemicals such as phenol and methanol used in the automotive, construction and packaging industries, and hydrogen and ammonia used to support decarbonisation efforts
Copper and aluminium used in batteries, computers, drones and a wide range of electronic devices.
Environmental chemicals are seldom encountered one at a time. Usually they are presented in mixtures which are becoming increasingly complex, requiring new ways of assessing their toxicity. Both the decline in biodiversity and increase in several human diseases continue to be linked to exposure to environmental chemicals. By monitoring the global megatrends in chemical use and horizon scanning to identify emerging chemical threats, mitigatory measures can be put in place to limit the risk of toxicity and minimise damage. Efforts are currently underway in several countries, notably within the European Union, to work towards achieving a toxic-free environment in which environmental chemicals in air, water and soil are reduced to a minimum. For example, green chemistry is being explored as a means of designing and synthesising useful chemicals and chemical production processes that are less damaging, yielding products that break down more readily into harmless substances in the environment.
Recorded lecture
Mike Depledge, who is Emeritus Professor of Environment and Human Health at the University of Exeter talks about global megatrends and how these might affect the use and environmental impacts of chemicals