Unlike the storms and droughts of climate change or the biodiversity collapse and imminent extinction threatening much wildlife, toxic waste is a silent killer, often unseen and hard to detect. It’s the third leg of our global crisis.

Undetected poison – like the coronavirus drifting on the breeze from an unstifled sneeze – has always been our worst nightmare. It hid in the unknown plant we sampled as we migrated out of Africa, rots in the flesh of purloined prey, witches bane, the assassin’s poison eyedropper and the unsuspected powder in the wine to kill a king. 

But these are nothing compared to the lethal substances now being produced by the industrial and military complexes across the planet. 

Many of these chemicals are new to nature, unpronounceable in name, unheard of to all but a few scientists and virtually indestructible. They are, we are told, the unavoidable byproducts of industrial progress, but we have great reason to fear them. When containment rules are bent – and money bends rules – the contagion spreads.

Most toxic waste is the byproduct of manufacturing, farming, water treatment systems, construction, automotive garages, laboratories, hospitals and other industries.

Compiling even a rudimentary list of hazardous chemicals in our environment is grounds for paranoia. Many fish bioaccumulate heavy metals such as mercury, lead and arsenic from factory and fertiliser runoff. Diesel fuel, particularly, releases particulate into the air that damages respiratory systems and regularly blankets cities such as New Delhi and Beijing in toxic fog. Nuclear waste takes several hundred thousand years to become inert.

Poly and perfluoroalkyl substance (PFAS) consists of about 4,000 chemicals that regularly turn up in fast-food wrappers, water and even human blood and can cause cancer, birth defects, thyroid disease and liver damage. Perfluorooctanesulfonic acid and perfluorooctanoic acid (PFOA) have such a long half-life they are known as “forever chemicals” and are used in the production of non-stick cookware and rainproof coats.

Quite apart from massive plastic pollution in the oceans, scientists have detected vast “dead zones” around the world, where hypoxic water lacks the necessary oxygen for marine life to survive. These result from blooms stimulated by agricultural runoff which leech oxygen out of the water. Analyses of sites around the world indicate that oxygen-minimum zones in the open ocean have expanded by several million square kilometres since the 1950s. 

Hundreds of coastal sites now have oxygen concentrations so low they limit the distribution and abundance of animal populations and alter the cycling of important nutrients. Rising nutrient loads coupled with climate change — each resulting from human activities — are the cause.

Can we contain the poisons we make? Often we fail. In August 2019 a fire broke out in an old Thor Chemicals mercury-recycling plant at Cato Ridge near Durban. Fortunately, the fire was contained, but it rang alarm bells. Inside were 3,000 tonnes of toxic mercury waste in barrels and sludge ponds. It had been piling up since the 1980s, imported into the country from foreign countries that wanted to get rid of a headache.

In the valley below the plant, medical researchers collected hair samples from 86 people along with fish and soil samples from Inanda Dam. Nearly 20% of the human hair samples had mercury levels above World Health Organisation (WHO) guidelines, half the fish samples were above WHO guidelines and 22% of soil samples were also problematic.

The first signs of trouble emerged in 1988 when a Natal Parks Board scientist found grossly deformed tadpoles and frogs in the streams surrounding the Thor factory. The tadpoles also contained extremely high levels of mercury. By the early 1990s, the first human casualties emerged when several workers from Thor were sent to hospital suffering from suspected mercury poisoning.

One of the worst cases of toxic leakage was in Bhopal, India. Thirty-six years ago, on the night of 2 December 1984, an accident at the Union Carbide pesticide plant released at least 30 tons of a highly toxic gas called methyl isocyanate, as well as a number of other poisonous gases.

The pesticide plant was surrounded by shanty towns, leading to more than 600,000 people being exposed to the deadly gas cloud that night. The gases stayed low to the ground, causing victims throats and eyes to burn, inducing nausea and many deaths. Estimates of the death toll vary from as few as 3,800 to as many as 16,000, but government figures now refer to an estimate of 15,000 killed over the years. 

Toxic material remains and, 36 years later, many of those who were exposed to the gas have given birth to physically and mentally disabled children. For decades, survivors have been fighting to have the site cleaned up, but they say the efforts were slowed when Michigan-based Dow Chemical took over Union Carbide in 2001.

Human rights groups claim that thousands of tons of hazardous waste remain buried underground and the government has conceded the area is contaminated. 

The horror of toxic contamination will be relived in a film starring Johnny Depp, Bill Nighy and Hiroyuki Sanada, directed by Andrew Levitas, to be premiered at the Berlin International Film Festival starting on Thursday (20 February). Depp relives the photographic investigation of the tragedy in Japan by Life magazine photographer W. Eugene Smith.

Minamata Bay and the Shiranui Sea were heavily polluted by wastewater mixed with mercury dumped by the Chisso Corporation’s factory, particularly by methylmercury. The highly toxic compound bioaccumulated in fish and shellfish in the bay which, when eaten by the people living around the bay, gave rise to Minamata disease.

Following his days as one of the most revered photojournalists of World War II, Smith became a recluse, disconnected from society and his career. But a secret commission from Life magazine editor Robert Hayes sent him to Minamata in Japan which was being ravaged by mercury poisoning.

Smith immersed himself in the community, documenting their efforts to live with Minamata Disease and the community’s passionate campaign to achieve recognition from the corporation and the Japanese government.

Armed with only his trusted camera, Smith’s images from the toxic village gave the disaster a heartbreaking human dimension and his assignment alerted the world to the horrors of toxic poisoning. The turning point was a single picture: Tomoko Uemura in Her Bath, taken in 1971. DM