What is particulate matter ?

According to  Vocabulary.com  ? Particulate Matter ? is  ? a small discrete mass of solid or liquid matter that remains individually dispersed in gas or liquid emissions (usually considered to be an atmospheric pollutant) ? ?. Scientifically the ? Particulate Matter ? is defined as ? the sum of all solid and liquid particles suspended in air many of which are hazardous. These particles vary greatly in size, composition, and origin « 

The literature on atmospheric particulate matter (PM) has increased enormously over the last 2 decades and amounts now to some 1500� papers per year in the refereed literature. Thus PM has become one of the most discussed topics of the society .

Due to their high importance for environmental policy , the  scientific interest in atmospheric particles grew and still growing enormously . Studies show that particulates impact the earth?s climate, precipitation levels and can have substantial negative effects on human health.

Causes of PM

 This complex mixture includes both organic and inorganic particles : Organic particulate matter is mainly caused by nature , due to volcanoes , dust storms , Tornado?s and hurricanes, sea spray and fires. Inorganic particulate matter is man-made since it?s generated by human activities such as coal combustion , oil combustion , wood combustion , construction , industry , agriculture , tobacco smoke , ?

Size of PM

Measurements of PM10 (particles with an aerodynamic diameter below 10 µm) have been performed in Europe for over 2 decades within national and international monitoring networks, including EMEP (European Monitoring and Evaluation Program), AirBase and, more recently, ACTRIS (Aerosols, Clouds, and Trace gases Research InfraStructure network). Conversely, PM2.5 (particles with an aerodynamic diameter below 2.5 µm) has a shorter time record and lower spatial coverage, due to a more recent introduction of PM2.5 target values by the European Air Quality directive.

Aerosol particles of natural origin (such as windblown dust) tend to have a larger radius than human-produced aerosols such as particle pollution.

 PM in Tunisia

In order to identify the source apportionment of particulate matter PM₁₀ and PM_2.5 in the southern Mediterranean coast of Tunis (Tunisia), three different sites characterized respectively by traffic, industries and being an urban background area are studied. The chemical characterization included a gravimetric determination of atmospheric particles mass concentration, measurements of the major anions (SO₄^2–, NO₃^–, Cl^–) and cations (Ca²⁺, Mg²⁺, K⁺, NH₄⁺) concentrations in the aerosol samples by ion chromatography and analysis of 18 elements by energy dispersion X-ray fluorescence. Aerosol ion balance of various PM₁₀ constituents are used to identify possible sources of the particulate matters. Thanks to these analysis, the particulate masses were reconstructed from the main possible constituents: crustal matter, primary and secondary pollutants, marine aerosols and organic matter. Wherever PM₁₀ and PM_2.5 were studied, PM₁₀ crustal elements and sea salt aerosols were mainly associated with the coarse fraction whereas primary and secondary anthropogenic pollutants as well as organic matter rather compose PM_2.5 fraction. In all the sites, PM₁₀ mass was mainly composed of crustal matter (41󈞞%) and poorly of sea salt (3𔃂%). And so aerosols chemical composition is heavily affected by dust winds from Sahara desert, with some contribution of local traffic and industries and only a slight direct impact of the nearby Mediterranean sea.

How to reduce particulate matter ?

PM  can be reduced by reducing the usage of Household products which create particulate matter , not  burning wood, leaves or any yard waste , replacing older engines with new engines because diesel vehicles are major source of particle pollution , walking, cycling , using public transport or sharing vehicle wherever possible .We have to pay attention to the maintenance of our vehicles. We also should conserve energy by using solar energy, bio-gas, rainwater harvesting etc.

sources :

EPA (Environmental Protection Agency)

Green Facts 

CEF (Conserve Energy Future)

Hindawi

ResearchGate

Perfect Pollucon Services 

Photo source :

ResearchGate