History reveals the hazards of dismantling trade protection

American farmers and food producers are said to be licking their lips at the trade opportunities opening up as Britain exits the single European market. But is the British public ready to consume chickens cleaned with chlorine, more genetically modified crops, fizzy drinks made with brominated vegetable oils (emulsifiers), or beef produced with growth-promoting hormones?

Practices such as these are currently prohibited in the EU, leading to a situation where health-related legislation, backed by scientific claims, acts as an effective trade barrier against US food products. Also citing scientifically verified health concerns, the USA has, in turn, banned EU-produced beef for decades after a series of BSE (or Mad Cow Disease) scares in the 1990s. While both continents will continue to use scientific claims to justify trade controls, where does the UK stand with its free trade aspirations?

Scientific claims surrounding the safety of food processing techniques are nothing new. Indeed, the use of new chemical food ingredients in 19th-century food provides one of the earliest examples of how governments and businesses appeal to science and scientists to help protect trade from foreign competition.

Aniline and azo dyes, produced for Europe’s booming 19th-century textile industry, were among the first commercial commodities, including drugs, perfumes and flavourings, which chemists began to synthesise. These chemicals were produced on an industrial-scale from coal-tar, a waste product of the gas industry.

The new synthetic dyes, whose commercial potential was first recognised by Britain’s William Perkin in 1856, were greeted by the Victorian press as ‘wonders’ of science. Within a few years, they began to be used to colour a wide range of food products such as butter, margarine, milk, wines, noodles, jams and confectionery.

The mid-19th century was a period when food adulteration was of considerable social concern.  Growing public distrust surrounded the provenance of food and its growing industrialisation. Governments and municipal authorities in Britain, continental Europe and the USA appointed chemists to test for food adulteration, while food producers recruited chemists to improve their food processing techniques and to fend off accusations of food manipulation.

While general awareness of the use of textile dyes in food increased, and reports of their possible toxicity emerged, health activists, politicians and businessmen turned to chemists to find answers. Chemists, however, were unable to agree on accurate methods to detect these new chemical substances in food or to assess their toxicity.

Many chemists believed the new dyes were preferable to the toxic metals and minerals – such as lead, copper and arsenic – previously used to colour food. These chemists argued that the new synthetic dyes were a harmless and scientific way to colour and preserve food, helping to increase the range and variety of food available to the public. Other chemists, however, claimed that the safety of the new dyes was not established, and that they were being used illicitly to disguise the quality of food products and deceive the consumer.

A lack of scientific consensus, differing political ideologies and successful lobbying by specific business groups led to a geographically divergent regulatory response. Germany was one the first countries to introduce legislation.

By 1887 Germany was the world’s leading producer of chemical dyes, and its chemical industry was a key constituent of its growing industrial economy. It was certainly in the interest of Germany, and German chemists and industrialists, to maintain public confidence in the new chemical substances being produced by companies such as BASF, Bayer and Hoechst. To strengthen public trust in the new chemicals, Germany and several other European countries, chose to ban a limited number of specified aniline dyes considered to be toxic.

This form of regulation meant that hundreds of other aniline and azo dyes not named in the legislation could be marketed as ‘harmless’ and used in food production, despite the fact that the health effects of most of the legally allowed dyes had never been assessed. As a result, chemical food additives effectively became legitimised as a result of legislation aimed to protect the consumer.

The USA, meanwhile, opted for a different and more precautionary approach. It was an approach that reinforced the use of the new textile dyes in food and proved beneficial for US businesses.

Instead of banning a few dyes known to be toxic, the US government recommended the use of just seven specified dyes for food colouring. All seven dyes had to be certified by the US government.  This strategy, which effectively opened up a new legitimised and specialised market for food dyes, was eagerly embraced by US chemical companies as an opportunity to differentiate themselves from their bigger European competitors.

Meanwhile, Britain, in pursuing laissez faire, free-market trade policies, opted for no prescriptive legislation. The British government relied on general food law that prohibited the use of food ingredients capable of poisoning or being used to defraud the consumer, without specifying any particular substances.

As detecting the use of the new dyes in food was almost impossible, and because there was little scientific consensus as to which dyes were harmful, this form of legislation effectively resulted in chemical substances becoming increasingly used, but rarely disclosed, as food ingredients.

In the late 19th century, the use of chemical dyes in food lay at the heart of a negotiation between freedom of trade, consumer choice and the support of commercial practices versus consumer protection, public health and greater transparency.

Legislation, allegedly based on science, failed to resolve the controversies surrounding the risks and benefits of chemical food additives, which remain the focus of considerable debate 150 years later. Instead, regulations, designed to protect public health, acted as trade barriers used to protect domestic businesses.

Although the regulatory list of permitted and safe food ingredients used today in Europe, so-called E-numbers, is more like the original regulatory approach adopted by the US in 1906, there is still a significant difference in opinion between European and US regulators, businesses and scientists as to which chemicals can be safely used in food.

History shows that interested parties invoke science for different purposes, whether consumer groups trying to protect public health or business trying to stave off competition. For the country’s future physical and economic health, the British public and British businesses need to keep a watchful eye on future trade talks between President Trump and Prime Minister May as Britain exits the trade and regulatory regime of the EU.

Carolyn Cobbold took her PhD at Cambridge University's Faculty of History.