In recent decades, change has defined our environment in the United States. Agriculture intensified. Urban areas sprawled. The climate warmed. Intense rainstorms became more common. But, says a new University of Wisconsin–Madison study, while those kinds of changes usually result in poor water quality, lakes have surprisingly stayed the same.

In the megacities that are home to nearly 10 percent of the world's 7.5 billion people, trees provide each city with more than $500 million each year in services that make urban environments cleaner, more affordable and more pleasant places to live.

In a recent study published in the online journal Ecological Modelling, an international team of researchers reported that in the 10 megacities they studied, tree-based ecosystem benefits had a median annual value of $505 million, which is equivalent to $1.2 million per square kilometer of trees. From another perspective, the value was $35 per capita for the average megacity resident.

Pollution is a greater global threat than Ebola and HIV, according to warnings by the World Health Organisation. 

According to its recent report, one in four deaths among children aged under five are now due to environmental hazards such as air pollution and contaminated water.

Previously this year, air pollution levels in London were worse than those in Beijing for a brief period - with the UK capital's pollutants frequently breaking UK limits. 

Researchers have discovered a new reaction mechanism that could be used to improve catalyst designs for pollution-control systems to further reduce emissions of smog-causing nitrogen oxides in diesel exhaust.

Bumblebees are less able to start colonies when exposed to a common neonicotinoid pesticide, according to a new University of Guelph study.

Prof. Nigel Raine has discovered that exposure to thiamethoxam reduces the chances of a bumblebee queen starting a new colony by more than one-quarter.

Elemental sulfur, the most heavily used pesticide in California, may harm the respiratory health of children living near farms that use the pesticide, according to new research led by UC Berkeley.

In a study of children in the Salinas Valley’s agricultural community, researchers found significant associations between elemental sulfur use and poorer respiratory health. The study linked reduced lung function, more asthma-related symptoms and higher asthma medication use in children living about a half-mile or less from recent elemental sulfur applications compared to unexposed children.

The mercury found at very low concentrations in water is concentrated along the entire food chain, from algae via zooplankton to small fish and on to the largest fish — the ones we eat. Mercury causes severe and irreversible neurological disorders in people who have consumed highly contaminated fish. Whereas we know about the element’s extreme toxicity, what happens further down the food chain, all the way down to those microalgae that are the first level and the gateway for mercury? By employing molecular biology tools, a team of researchers from the University of Geneva (UNIGE), Switzerland, has addressed this question for the first time. The scientists measured the way mercury affects the gene expression of algae, even when its concentration in water is very low, comparable to European environmental protection standards. Find out more about the UNIGE research in Scientific Reports.

Exposure to high levels of air pollution increased stress hormone levels and negative metabolic changes in otherwise healthy, young adults in a recent study conducted in China. Air purifiers appeared to lessen the negative effects, according to new research published in the American Heart Association’s journal Circulation.

Researchers focused on fine particulate matter (PM2.5) – a component of air pollution emitted from vehicles, factories, power plants, fires and smoking – because many studies have suggested this type of major air pollutant might lead to cardiovascular and metabolic health consequences, according to Haidong Kan, M.D., Ph.D., study author and professor of environmental health sciences at Fudan University in Shanghai, China.

The Montreal Protocol, the international treaty adopted to restore Earth’s protective ozone layer in 1989, has significantly reduced emissions of ozone-depleting chemicals from the United States. In a twist, a new study shows the 30-year old treaty has had a major side benefit of reducing climate-altering greenhouse gas emissions from the U.S.

That’s because the ozone-depleting substances controlled by the treaty are also potent greenhouse gases, with heat-trapping abilities up to 10,000 times greater than carbon dioxide over 100 years.

Famously, the use of caged birds to alert miners to the invisible dangers of gases such as carbon monoxide gave rise to the cautionary metaphor “canary in a coal mine.”

But other than the fact that exposure to toxic gases in a confined space kills caged birds before affecting humans — providing a timely warning to miners — what do we know about the effects of air pollution on birds?

Not as much as you’d think, according to researchers from the University of Wisconsin–Madison.