/ 14 November 2015

Climate’s villain makes you dof

Breathless: Research shows that levels of carbon dioxide in the air we breathe have risen to the dangerous 400 parts per million
Breathless: Research shows that levels of carbon dioxide in the air we breathe have risen to the dangerous 400 parts per million

Failing to concentrate at work? Turning to your cellphone to add up a simple sum? Unable to think beyond the next cup of stimulant-laden coffee? If you’re nodding your head, then maybe you’re another victim of deadly carbon dioxide.

The colourless and odourless gas is an unusual villain. For much of human history, it has been a friend. Elevated levels 10?000 years ago sparked the agricultural revolution and modern-day civilisation. Humans evolved to process concentrations of around 200 parts per million. But a few centuries ago the world economy exploded, thanks to the digging up and burning of fossil fuels. This spewed carbon dioxide into the atmosphere. Average ambient levels now hover at around 400 parts per million. That concentration of particles traps heat and warms the planet – leading to most carbon-related research looking at its effect on global warming.

But new research from Harvard University shows that this dramatic rise in CO2 is eating away at our cognitive ability, especially in closed environments, such as offices. Here levels can reach 3 000 parts per million – lowering cognitive ability by at least 21%.

This relatively new research focus came to its first definitive finding in 2012, courtesy of the Lawrence Berkeley National Laboratory in the United States. The study – Is Carbon Dioxide an Indoor Pollutant? Direct Effects of Low-to-Moderate Carbon Dioxide Concentrations on Human Decision-making Performance – found CO2 levels in cities were on average 100 parts per million higher than the global average. In specific areas, such as schools, these levels could rocket up to 3 000 parts per million. In published double-blind tests, the laboratory found increased CO2 concentrations led to “statistically significant and meaningful reductions in decision-making performance”.

The findings were backed up by research by Harvard University’s healthy building and environmental health and human habitation units, published last month in the peer-reviewed Environmental Health Perspectives journal.

Focusing on CO2 levels in workspaces and homes, the team put numbers to the reduction in cognitive functioning: for every 400 parts per million extra CO2, a person’s cognitive scores drop by 21%. These scores include basic cognitive functioning, crisis response, information usage and the ability to think long-term and plan.

No similar research appears to have been carried out in South Africa but an increasing amount is being done overseas. Nasa takes the findings as fact, based on its own observations at the International Space Station. Early in its operation, the space administration found astronauts were adversely affected when CO2 levels in the station increased.

Nasa then limited CO2 levels and started researching the effects of increased CO2 concentrations, which are continually rising.

The World Meteorological Association says 2015 will be the first year where global CO2 levels are consistently over the 400 parts per million mark. This was symbolically reached at one research station in the Pacific earlier this year. Now that level is the norm.

To avert the climate change effect of these emissions – more heat trapped, leading to a warming planet – negotiators will meet at COP21 in Paris later this month to hammer out an agreement to lower emissions. Now the negotiators will have a public health argument to support their efforts, if they can concentrate in the cramped negotiating offices.


Lead dims people’s potential

Much like excess carbon dioxide concentrations, lead poisoning comes from an invisible source and steals people’s futures. For much of the 1900s, that source was the extra lead added to petrol to give cars more power.

South Africa’s fuels have had among the highest levels of lead in the world.

In the early 1990s many countries started banning lead in petrol and myriad other places. In seven of these countries research shows that this resulted in a dramatic dip in violent crime 23 years after lead was phased out.

Tracing this anomaly led researchers to lead. One report from the United States found that exposure to lead results in a loss in IQ points – which then set people back and pushed them into crime to make ends meet. The violence of the crime was exacerbated by that exposure.

Summarising the work, the US investigative publication Mother Jones found that: “Massive lead exposure among children in the post-war era led to larger numbers of violent crimes in the 1960s and beyond.”

The startling effect of lead had long been hidden because it did not affect many middle-class children, who had good schools and a support system to help them overcome it. In poor children, other factors such as a poor diet and education were blamed for problems. But recent research shows that lead poisoning has been instrumental in hampering the prospects of children already on the edge.

This situation is particularly acute in South Africa. The apartheid regime moved people into areas where there was little chance for a healthy environment – downwind of mines and industrial areas.

This ensured that environmental factors, such as carbon emissions and lead exposure, add to other stresses and rob people of their potential.

Speaking to the Mail & Guardian last year, Angela Mathee, director of the Medical Research Council’s environmental health research unit, said lead poisoning and other environmental pollutants had the effect of dampening the potential of entire communities.

“At a community level, the bell curve of IQ gets shifted to the left,” she said. “At the lower end, there is an increased requirement for remedial education.”

But this was rarely available; instead, the number of “bright sparks, leaders, scientists and entrepreneurs” was greatly reduced in these areas. – Sipho Kings