These days, environmentalism has become synonymous with the fight against climate change. But good green campaigners know that more immediate environmental challenges still exist.

That reality hit home yesterday when the United Nations said it will send an emergency team to Nigeria, after 200 children died in an outbreak of lead poisoning related to gold mining in the northern state of Zamfara.

More than 18,000 people have thus far been affected in seven villages. As The Guardian reports, “In all cases, villagers had been grinding ore by hand to search for gold when they unwittingly freed lead particles also contained in the rock.” Local water supplies and soil in villages have become contaminated.

The death toll and figure of those affected will likely rise. Lead poisoning is insidious: it can have debilitating long-term effects, such as decreased bone and muscle growth, poor muscle coordination, damage to the nervous system, kidneys, and hearing and speech and language problems. Children suffer more because their size makes them more vulnerable to the effects.

Lead poisoning has been a rumbling problem in Zamfara since early this year, when doctors from Médecins sans Frontières noticed an unexpectedly high mortality rate among children; locals blamed the death on malaria, but blood tests showed high concentrations of lead. Slowly, the scope of the problem unfolded, until on Monday, Nigerian authorities asked for help, and the United Nations’s Office for the Coordination of Humanitarian Affairs (OCHA) decided something had to be done. It allocated $2 million to respond to the outbreak, and deployed a five member environmental emergency team at the request of the Nigerian authorities, according to an OCHA press release. The response team will sample and analyse soil and water, and develop recommendations to help national authorities combat the problem as quickly as possible. According to the release,

The response will involve medical care for the most severe cases of lead poisoning among children under five, and decontamination of houses and villages. Both are needed because medical treatment alone is ineffective if children return home to contaminated homes and are reexposed to lead. Many children over five as well as adults who have been tested in the affected areas also have extremely high levels of lead in their blood and may require treatment.

Medical historians and epidemiologists have long known an embarrassing secret about medicine: despite all its high-tech gadgetry, modern medicine has played only a very small role in extending life expectancy over the last hundred and fifty years. Environmental health—sanitation, detoxification of living and working environments, access to healthy food—has had the greatest impact, by far.

This is what poverty campaigners refer to when they speak of “environmental justice.” Is it fair that the the bulk of the world’s wealthy populations now live in clean, safe environments, while many of the world’s poor are exposed to unclean environments, often the result of toxins from the global economy’s dirty industries? Of course, solving environmental injustice can be a tricky task—the Zamfara lead-poisoning was caused not by a negligent mining company or currupt local officials, but by a gold rush among local populations. As the OCHA release states, “Investigations revealed that the cause is acute lead poisoning from the artisanal (emphasis mine) processing of lead-rich ore for gold extraction, taking place inside houses and compounds.” This is why many poverty campaigners believe environmental justice is inseperable from social justice, and that (sustainable) development is an environmental imperative. Improving the poor’s standard of living is an environmental, as well as social, obligation.

Last month, I wrote about how economic instability has sent gold prices soaring, setting up a battle between prospectors and conservationists. I was referring, of course, to developed countries. As the sad case of Zamfara’s lead poisoning shows, for too many people, protecting the local environment is more than just safeguarding beautiful scenery, or a habitat for local owls. Nor is it contained to altitudinous concerns about carbon concentrations in the atmosphere. For too many people, environmentalism is about the soil and water around them, and it’s a question of life and death.