In a report released on June 28, 2018, by the French Agency for Health Safety (ANSES), a list of thirteen new air pollutants was presented.
Several air pollutants that are harmful to human health are already regulated and closely monitored at the European level (in accordance with the guidelines from 2004 and 2008): NO2, NO, SO2, PM10, PM2,5, CO, benzene, ozone, benzo(a)pyrene, lead, arsenic, cadmium, nickel, gaseous mercury, benzo(a)anthracene, benzo(b)fluoranthene, benzo(j)fluoranthene, benzo(k)fluoranthene, indeno(1,2,3,c,d)pyrene and dibenzo(a,h)anthracene.
Some pollutants, such as ozone, PM10, and PM2.5, are well-known and frequently cited by the media. Others remain less familiar. This list is not exhaustive, given the number of substances that are emitted in the air.
How did ANSES identify these 13 new pollutants? What criteria were used? Take a closer view.
Selection of candidates
It is not an easy task to identify new substances that should be monitored in ambient air. The process is like selecting the best candidate for a beauty pageant. It is important to choose independent judges who are experts in their field. Then, it is necessary to determine the rules for selecting the top candidates.
Over the last two years, the working group of experts has developed a method to consider the chemical and physical diversity of candidates in ambient air.
In order to gather participants for this “beauty competition,” the experts created a list of chemicals that are of interest but have not yet been regulated. They did not include some candidates, such as pollen, mold, radioelements, and greenhouse gases, because other studies assessed them or because their expertise was outside of the scope.
This list is based upon information provided by French research laboratories such as the Laboratoire des Sciences du Climat et de l’Environnement LSCE and Laboratoire Interuniversitaire des Systemes Atmospheriques LISA. This list is based on information provided by French research laboratories like the Laboratoire Interuniversitaire des Systemes Atmosphériques (LISA) and the European Environment Agency (EEA), and also by experts from international and national organizations such as the European Environment Agency and Canada (US-EPA), and by inventories created by international organizations like WHO.
This list has been supplemented with a detailed study of the latest international and national publications that deal with “emerging” contaminants.
Imagine the stampede if this final list had 557 candidates.
Ranking the Finalists
The candidates are divided into four groups based on data on atmospheric measurements and the inherent danger of each candidate.
In Category 1, substances are classified according to their potential risk to health. There are also categories 2a and 2, which include candidates for whom more information must be gathered from air measurements and health impact studies. In Category 3, non-priority substances are those with low concentrations of airborne pollutants and no health effects.
Some exceptional candidates, including ultrafine particles with diameters less than 0.1um and carbon soot due to the potential impact on health, were reclassified.
The experts then ranked the pollutants identified in Category 1 in order to determine the undisputed winner of this unique beauty contest.
The winner is…
According to ANSES, gas 1,3-butadiene was ranked first among the 13 new air pollutants that need to be monitored. Ultrafine particles and carbon soot are also recommended for increased monitoring.
1,3-Butadiene, a toxic gas, is produced by combustion, including motor vehicle exhaust pipes, industrial processes (plastics and rubber), and heating. In France, several temporary measurement campaigns revealed that the pollution often exceeded its toxicological value (TRV), a value that establishes the relationship between dose and effect.
The fact that it topped the podium is not surprising. It won a prize in both the United Kingdom (UK) and Hungary (Hungary), two countries with reference values for the concentration of 1,3-butadiene in the air. The International Agency for Research on Cancer classified 1,3 butadiene for humans as a carcinogen as early as 2012.
It is recommended that the ten pollutants listed in the ANSES be monitored more closely. These ten pollutants, with exceedances in TRV observed in specific (especially industrial) contexts, are, in decreasing order of risk, manganese, hydrogen sulfide, acrylonitrile, 1,1,2-trichloroethane, copper, trichloroethylene, vanadium, cobalt, antimony, and naphthalene.
This is the first step in adding 1,3-butadiene to a list of substances that France currently regulates. By the end of 2019, if the French government submits this proposal to the European Commission, it will be included in ongoing revisions of the 2008 Directive on Monitoring Air Quality.
This classification method is adaptable, so there’s a good possibility that in the future, new competitions to find other candidates will be held.
