While the chemical industry has been crucial to manufacturing and modern life, it has also been a major cause of pollution and ecological damage. How has it adapted to these environmental challenges, and is it going green?
When did the chemical industry become a big pollution problem?
Our modern world is a chemical one: plastics, cosmetics, perfume, soap, oils, fats, food additives, dyes, cement, rubber, pharmaceuticals, fertilisers, pesticides, glass, textiles and refrigerants are all—directly or indirectly—the result of industrial chemistry.
This chemical industry emerged in its modern sense in the the mid-1700s, transitioning from craft-based cottage industries, such as tanneries, dye-works, glassworks and soap-works, to factories that applied scientific methods and knowledge on an industrial scale.
With this development of new industrial ways of producing chemicals crucial to manufacturing came new kinds of pollution.
In the late 1700s the French chemist Nicholas Leblanc devised an industrial process for making soda ash, a material vital to the soap, glass, paper and textile industries. He succeeded by heating a widely-available commodity—sea salt—with sulphuric acid. The resulting salt cake (sodium sulfate) was then mixed with limestone and reacted with coal (carbon) to produce black ash, from which soda ash (sodium carbonate) could be extracted.
Leblanc was persecuted during the French Revolution, as a result of which his process wasn't widely adopted in France. Across the channel, however, factories sprang up in Newcastle, Edinburgh, Glasgow and Liverpool, and Britain went on to produce more soda ash than all other countries combined.
The environmental impacts were considerable. Its key waste product, hydrochloric acid gas, polluted the air around factory towns and cities, killing almost all vegetation and livestock.
As a result, Leblanc factory owners were frequently taken to court, charged with 'creating and maintaining a nuisance' and ordered to compensate communities.
This eventually led to the first environmental legislation in the UK—the Alkali Act of 1863, which capped the release of hydrochloric acid gas from factory chimneys. Enforced by inspectors, it would be extended to cover other chemical pollutants.
To comply, Leblanc producers instead reacted the acid with charcoal and water, turning it from gas to liquid, then dumped the resulting solution into rivers and seas where it devastated aquatic life.
Water pollution was less legislated against than air pollution at this time, when environmental pollution was understood by industry in terms of its impact on workers or a local community. Ecological conceptions of pollution would not be common until the 1960s.
The first ‘green’ approach to industrial chemistry
In the 1860s Ernest Solvay, a Belgian chemist and industrialist, began developing an alternative process of producing soda ash to Leblanc’s.
Solvay introduced a new concept to industrial chemistry—the continuous process. The main waste products are recycled back into the first stage, allowing for continuous operation. Although motivated by the economic benefit of reducing waste, an environmental consequence was that it minimised pollution from by-products.
The first Solvay plant was established at the unlikely site of a country estate in Winnington, Northwich, England, by British and German business duo John Brunner and Ludwig Mond. Their factory became the biggest soda producer in the world, leading to the demise of the Leblanc process by the early 20th century.
Recycling was not only key to the process itself but became part of wider operations at Winnington—for example, excess steam produced by the process went into heating office buildings.
Brunner Mond expanded into other areas, eventually merging in 1926 with two other chemical giants to form Imperial Chemical Industries (ICI), which became Britain’s—and one of the world’s—largest manufacturer in the 20th century.
The petrochemical revolution
The biggest change to the chemical industry in the 20th century was the switch from coal to petroleum and natural gas as the raw materials, also known as feedstocks, for making carbon-based chemicals.
This new petrochemical industry began in 1920s America, as oil and chemical companies teamed up to make economic use of by-products from petrol fuel production. The resulting petrochemical products transformed the world.
The US chemical giant DuPont alone introduced 'wonder' materials such as the artificial silk Nylon, synthetic rubber Neoprene, super-strong Kevlar, stretchy Lycra, non-stick Teflon, and polyester—the latter developed by DuPont’s British rival, ICI, into the clothing textile we know today.
Accelerated by the Second World War, the petrochemical industry infiltrated almost every aspect of our lives: plastics in consumer technologies; synthetic detergents that displaced soap; the chemicals that made home refrigeration possible without poisoning us.
Food production became reliant on its new fertilisers and pesticides, which also successfully combatted insect-borne diseases like malaria—at least until insects started to develop pesticide resistance in the 1950s.
But hidden behind the wonder of these affordable and transformative petroleum-based products was an enduring environmental cost.
Rachel Carson and the book that changed our relationship with chemicals
Published in 1962, Rachel Carson’s Silent Spring made an immediate impact—all the way up to the US President, John F Kennedy, who that year cited Carson’s book in a speech and commissioned a government report into its findings.
Carson, a marine biologist with a literary talent, had been working on Silent Spring for four years. She was already a bestselling author, but Silent Spring made her internationally famous. It sold millions, and is now considered one of the most important, influential books of the 20th century.
Poetic and impeccably researched, Silent Spring took aim at the indiscriminate use of chemical pesticides, which at the time were sprayed over vast swathes of agricultural land, sometimes from planes. The ecological impact, Carson revealed, was devastating.
Carson’s number one target was the insecticide DDT. Toxic and carcinogenic to humans and animals, Carson showed that DDT increased in concentration as it moved up through the food chain, from insects to birds and beyond. And once unleashed in the environment, it did not break down, but travelled through ecosystems. Later DDT was found even in remote places like Antarctica, in penguins.
The chemical industry, which Carson held responsible, attempted litigation to stop Silent Spring being published. When that failed, the industry launched a coordinated smear campaign that ranged from sexist accusations of hysteria and irrationality to pamphlets parodying Carson’s style, such as Monsanto’s ‘The Desolate Year’, which aimed to scare readers with a B-movie-inspired horror story of chewing insects taking over the planet.
Silent Spring’s legacy was profound. DDT and all other pesticides Carson cited would be banned in the US by the mid-1970s. Today, DDT belongs to a class of POPs (persistent organic chemicals) that are internationally outlawed and highly regulated. Her ecological take on chemical pollution led to the establishment of environmental regulation bodies.
Silent Spring would also inspire the environmental movement, which gathered momentum in the following years, as organisations like Greenpeace, Friends of the Earth and the first organic farming certification body, the UK’s Soil Association, were established.
Has the chemical industry adapted to environmentalism?
Increasing environmental awareness in the 1970s brought about change in the chemical industry, which had an acute image problem in the wake of Carson’s book and a number of chemical-related accidents, such as the Torrey Canyon oil spill in 1967—the UK’s worst ever oil spill—and the Seveso disaster of 1976, which led to dioxin poisoning in Italy.
In the late 1960s, Britain’s ICI repurposed a paint research lab in Brixham, Devon, to establish a division devoted to environmental monitoring, which carried out extensive tests of chemical pollutants in water for the UK’s industrial sector.
ICI also began a programme of environmental clean-ups of polluted land around factories. One site, Saltholme Pools, near ICI Billingham’s fertiliser plant, became a 1,000-acre nature reserve of pools and grassland.
Yet increasing evidence regarding the health impacts of some of the most commercially successful chemicals resulted in a series of landmark legal cases, revealing industry cover-up.
The largest was DuPont, who paid out $670.7 million to thousands of inhabitants of a West Virginia town, after the chemical company had been judged culpable for the cancers caused by pollution from their Teflon factory.
DuPont had knowingly contaminated the town’s water with PFOA, part of a class of persistent and toxic chemicals (PFAS) used widely in consumer products, from non-stick coating of frying pans to waterproof clothing. The settlement was double that of Erin Brockovich’s famous legal action in another case of groundwater chemical pollution.
Regulation has forced chemical companies to adapt when evidence of environmental and health damage has been found. Perhaps the most famous example is chlorofluorocarbons (CFCs), a petrochemical refrigerant developed in the 1930s that was internationally banned in 1987 after scientists discovered their role in causing a hole in the ozone layer.
But the answer the chemical industry found was to switch to chemically similar molecules, hydrofluorocarbons (HFCs), which it turned out did as much damage and were subsequently banned too.
Can chemists help turn the industry green?
In the last 30 years, chemists have tried to find new ways of doing chemistry on an industrial scale that starts from environmental principles.
This relatively young discipline, dubbed ‘green chemistry’, aims to eliminate toxic pollutants from the beginning of chemical processes, rather than finding ways to contain them afterwards.
One early example is a technology called supercritical fluid extraction, which uses non-toxic solvents such as carbon dioxide to extract things like caffeine from coffee or vitamins from plants. It's now used widely in industries such as coffee, essential oil and vitamin production.
Green chemists are also working on approaches to move away from fossil fuel feedstocks—such as petroleum used to make plastics—and encourage the recycling of biowaste to make new things, such as biodegradable plastics derived from food waste.
A key ambition is to find ways to make all industrial chemistry circular in its economy, which means all by-products and waste are either recycled into the same process (like Solvay’s method of producing soda ash) or used by new processes by other closely-located plants—networks of these are called eco-industrial parks.
The success of green chemistry will depend on both continued research and regulation of environmentally dangerous chemicals. It seems likely that circular approaches that minimise waste and maximise recycling will become the economic choice for large industrial companies. The environmental movement had a huge influence on reforming the chemical industry, and has an important role to play in ensuring our chemical future is safe, ecologically-minded and sustainable.
Find out more
- Colin A. Russell (editor), Chemistry, Society and Environment: A New History of the British Chemical Industry, 1990
- Carol Kennedy, ICI: The Company that Changed Our Lives, 1993
- Benjamin Ross and Steven Amter, The Polluters: The Making of our Chemically-Altered Environment, 2010
- Erik M. Conway and Naomi Oreskes, Merchants of Doubt, 2010
- William Souder, On a Farther Shore: The Life and Legacy of Rachel Carson, 1998
- Ernst Homburg et al (editors), The Chemical Industry in Europe, 1850–1914: Industrial Growth, Pollution and Professionalisation, 1998
- Nature, Chemistry: It's not easy being green
- US Environmental Protection Agency, Green chemistry
- The Guardian, Sustainable business: Green chemistry
- The Guardian, Salted away (about Saltholme pools)
- The New York Times, The promise and perils of petrochemicals
- The New York Times Magazine, The lawyer who became DuPont's worst nightmare
- The Devil We Know (documentary about DuPont and PFAO)