Climate change could increase crop toxicity and zoonotic diseases around the world according to a UNEP report released on Friday.
UNEP’s Frontiers report identifies, highlights and offers solutions to six emerging issues, including the threat to human health posed by the alarming amount of plastic waste in oceans and the crucial role the world’s financial sector can play in driving the planet to a low-carbon, resource-efficient future.
Climate change is already having a major impact on food safety and security and the report looks at how drought and high temperatures can trigger the accumulation of chemical compounds in crops making them toxic to animals and humans.
The most likely to be affected are wheat, barley, maize and millet. These crops which are staples are most susceptible to nitrate accumulation, which is caused by prolonged drought. In acute cases, nitrate poisoning in animals can lead to miscarriage, asphyxiation and death. This ruins the lives of smallholder farmers and herders.
The consequent phenomenon of heavy rains breaking prolonged droughts can also result in the dangerous accumulation of hydrogen cyanide or prussic acid in crops like flax, maize, sorghum, arrow grass, cherries and apples.
Aflatoxins, which are fungal toxins that can cause cancer and stunt foetal growth, are another emerging problem in crops. The risk of aflatoxin contamination, especially in maize, is expected to increase in higher latitudes due to rising temperatures.
Another issue is that diseases passed from animals to humans are on the rise. The Frontiers report shows how this rise is closely linked to the health of ecosystems: human activities that encroach on natural habitats enable pathogens in wildlife reservoirs to spread more easily to livestock and humans.
Recent years have seen the emergence of several zoonotic diseases including ebola, bird flu, middle east respiratory syndrome, Rift Valley fever and Zika virus disease. The pathogens that cause these diseases have wildlife reservoirs that serve as their long-term hosts. In the last two decades, emerging diseases have had direct costs of more than $100 billion. If these outbreaks had become human pandemics, the losses would have amounted to several trillion dollars, the report states.
Plastic pollution also poses a threat to oceans posing risk to human health through the consumption of contaminated food. These tiny plastic particles – between the size of an ant and virus – are found in water systems throughout the world and in the stomachs of everything from zooplankton to whales. A number of studies analysed in the report are underway to determine the risk this poses to human health.
The financial sector, by reducing greenhouse gas emissions from its factories, could bring about positive environmental change.
Climate change has seen loss and damage to different ecosystems and scientific evidence suggests that losses and damages from climate change are inevitable, with profound consequences for ecosystems, people, assets and economies. This is already happening. The heat waves of 2003 are a good example of what happens when efforts to mitigate and adapt to changes in the climate fail: 30,000 people died, glaciers decreased, permafrost thawed. From this, the European Union’s agricultural sector lost $14.7 billion.
The report examines a number of other case studies on recent sudden and slow-onset events that have caused losses and damages to ecosystems and presents a range of tools that will help manage these problems in the future.