Study Of North Atlantic Ocean Reveals Decline Of Leaded Petrol Emissions
(Click to enlarge) A new study of lead pollution in the North Atlantic provides strong evidence that leaded petrol emissions have declined over the past few decades (Credit: NASA Goddard Space Flight Center/Flickr).
A new study of lead pollution in the North Atlantic provides strong evidence that leaded petrol emissions have declined over the past few decades.
(From Phys.org / by Colin Smith)– For the first time in around 40 years, scientists have detected lead from natural sources in samples from this ocean. In the intervening period, the proportion of lead in the ocean from manmade sources, most importantly leaded petrol emissions, had been so high that it was not possible to detect any lead from natural sources.
Trace metals such as lead are continuously recycled on land, in the ocean and in the atmosphere, and are important barometers that help scientists to understand planetary processes. Scientists are particularly keen to monitor levels of lead from natural sources, such as windblown dust, and lead from manmade sources, such as burning coal, to determine the impact of industrialisation on the planet and levels of pollution.
A team of scientists from Imperial College London, and their collaborators, analysed the chemistry of seawater samples collected from across the tropical North Atlantic in 2010 and 2011. The aim of the study, published in the journal Nature Communications, was to determine variations in the proportions of natural and manmade lead in the tropical North Atlantic Ocean.
The scientists found that up to 50 per cent of the lead was from natural sources, which they say reflects a decrease in the amount of lead pollution emitted from combustion engines. They caution however that this finding is confined to a specific area of the ocean, which is expected to receive particularly high inputs of natural lead, and that continuing pollution from sources such as coal-burning and smelting processes are still overwhelming natural lead elsewhere in the Atlantic ocean.
Read the full article here: http://phys.org/news/2016-09-north-atlantic-ocean-reveals-decline.html#jCp